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Animal Science (ANSC)…………………………………………………… 27

Crop Protection (CP)……………………………………………………….. 30

Forages (FOR)……………………………………………………………… 40

Horticulture (HORT)……………………………………………………….. 45

Roots and Tubers (R&T)…………………………………………………… 50

General Agriculture (GENAG)……………………………………………... 53

Animal Science (ANSC)…………………………………………………… 66

Crop Protection (CP)……………………………………………………….. 68

Forages (FOR)……………………………………………………………… 76

Horticulture (HORT)……………………………………………………….. 80

Roots and Tubers (R&T)…………………………………………………… 83

General Agriculture (GENAG)…………………………………………….. 85

Agronomy and Natural Resources (ANR)

ANR 1- Case study on estimating soil erosion and potential water pollution in the Caura Valley watershed of Trinidad. A. Redhead, G. Gouveia, and G. Eudoxie. University of West Indies.

Erosion is among the most critical global environmental hazards. Quantitative data on the rate of soil erosion in Trinidad and Tobago is very limited and reliability is a major problem. Eroded material with nitrogen and phosphorous adsorbed to the particles can cause severe pollution in the form of eutrophication and sedimentation of the Caura River. The northernmost part of the watershed has been a major vegetable production area for decades with many farmers engaged in year-round intensive production on the gently and moderately sloping terrain just on the banks of the main river. The main objective of this study is to develop an erosion index for farmers to quantify erosion occurring on their farms based on land use and other management characteristics. The establishment of nine erosion plots on active production sites and on control non-production sites took place in the rainy season of 2005 between the months of September and October. These plots were placed on slope categories 0 to 5%, 5 to 10% and 10 to 17%. Runoff from each plot was collected and tested for levels of phosphorous, nitrogen and total suspended solids. The control non-production sites (10 to 17% slope) contained the highest values for total suspended solids. The active production sites (0 to 5% slope) contained the highest amounts of nitrogen and phosphorous. It is important to note, however, that as runoff increased, the quantity of nitrogen increased but phosphorous remained relatively constant. Details of the index developed will be presented.

ANR 2 - A procedure for estimating hourly crop evapotranspiration. E. W. Harmsen¹, V. H. Ramírez², J. E. González³, M. D. Dukes⁴, and X. Jia⁴. ¹Department of Agricultural Engineering and Biosystems, ²Department of Agronomy and Soils, University of Puerto Rico – Mayagüez Campus. ³Santa Clara University, ⁴Department of Agricultural and Biological Engineering, University of Florida.

A method is presented for estimating the hourly actual evapotranspiration (ET) from short natural vegetation or agricultural crops. The method consists of equating the ET flux equations based on the generalized Penman-Monteith (GPM) combination method and a humidity gradient (HG) method. By equating the GPM and HG expressions, a single unknown parameter, either the bulk surface resistance (r_s) or aerodynamic resistance (r_a), can be determined. In the procedure, the value of the resistance factor is adjusted by an automated procedure until the daily ET time series curves from the two methods approximately coincide. An overview of the technical approach and the results of a comparison between the new method and two eddy covariance systems at the University of Florida at Gainesville and The University of Puerto Rico Agricultural Experiment Station at Lajas, PR, respectively, are provided. To illustrate the utility of the method an example is presented in which ET and the aerodynamic resistance were estimated for a sugar cane (Sacharum officinarum) plot using one-hour values of the surface resistance, based on measured stomatal resistance and leaf area index. Preliminary results are also presented from a drought tolerance study of common bean (Phaseolus vulgaris L.) at Juana Díaz, PR, in which the ET method is compared with estimates of ET from drainage lysimeters. The methodology, which is significantly less expensive than the eddy covariance approach, could be valuable for validating short-term estimates of ET from remote sensing techniques.

ANR 3 - Turfgrass establishment, maintenance and management in stress situations in Trinidad and Tobago. R. Springer, G. Eudoxie, and G. Gouveia. University of West Indies.

Sports fields in Trinidad and Tobago are increasingly being used to host a range of international, regional and local sporting events such as cricket, football, hockey, golf and rugby. The fields are exposed to heavy traffic in many of these sports and the turf is subjected to wear, compaction and damage over time if not properly cared for. The conditions of the fields affect the performance and competitiveness of the users and hence the quality of entertainment and the level of play produced. The majority of sports fields in the country do not utilize irrigation systems to maintain turf cover during the dry season and are mainly rain fed. Bermuda grass (Cynodon dactylon), St. Augustine grass (Stenotaphrum secundatum) and Zoysia grass (Zoysia spp.) are tropical turfgrasses that are drought-tolerant and have deep root systems. A study is in progress with the following objectives: to characterize the physical and chemical properties of soils under important turfgrass species; to analyze current methods being utilized to manage local sports fields; to develop proper soil, water and fertilization practices for the management of turfgrasses; to understand the nutritional and other requirements of turf grasses for rapid recovery from stressful situations. Data will be presented based on experimental plots established on both non-sporting and sporting sites.

ANR 4 - Clay and organic matter effects on splash detachment. M.N. Wuddivira, G. Gouviea, R.J. Stone, and E.I. Ekwue. University of West Indies.

Soil erosion is a worldwide phenomenon that is second only to population growth as the biggest environmental problem. It destroys croplands, reduces soil productivity and makes waterways more prone to flooding and to contamination from fertilizers and pesticides. In the Caribbean, population pressure, cultivation on steep slopes, high rainfall intensities, preponderance of soils of medium to heavy textures with weak structures often exacerbate the effects of soil erosion. Aggregate breakdown and splash detachment are initial steps in the erosion process and control measures are most effective if they are aimed at reducing them. Clay and organic matter binding and cementing abilities increase aggregate stability and reduce aggregate breakdown, splash detachment and erosion. But increasing clay content in the aggregate under fast wetting has been shown to strengthen aggregate disruptive and detachment forces. We hypothesize that these forces will be suppressed if increase in clay is accompanied by an appropriate increase in organic matter content. Six soils from Trinidad with three clay levels (low, medium and high) and two organic matter levels (low and high) were used. Splash cups (7.3 mm in diameter and 5 mm high) were packed with <5 mm size aggregates of the samples and placed under rainfall simulator at 9% slope. Simulated rainfall of 120 mmh^-1 intensity was applied for 10 min to assess aggregate breakdown and splash detachment and for 60 min to assess runoff. Aggregate stability was also assessed by using single sieve apparatus. Aggregate stability increased with increase in clay. The significantly higher aggregate stability of the medium clay-high organic matter soils over its high clay-low organic matter counterparts implies that a threshold clay content exists beyond which an accompanying increase in organic matter is required to mitigate detachment mechanisms and erosion.

ANR 5 - Harnessing the potential in native herbaceous legume germplasm. J. P. Muir, E. Valencia, and S. Weiss. Texas Agricultural Experiment Station.

Plant ecosystems bordering the Caribbean basin are rich in native herbaceous legume germplasm that is threatened by land clearing, over-grazing and urban development. These species merit conservation because of their contribution to biodiversity, ecosystem stability, di-nitrogen fixation, and nutritive contributions to native and domesticated fauna diets. If domesticated, they are potentially useful in human nutrition, native ecosystem restoration, rangeland reseeding, right-of-way soil stabilization, high-nitrogen green manure and cultivated pastures. North central Texas alone has fifty such herbaceous legume species. They are different from exotic or naturalized plants which have been introduced either intentionally for cultivation or unintentionally as invasive weeds. They have a distinct advantage over exotics if used within their regions of adaptation since they do not pose an invasive weed threat. A program to collect and evaluate native herbaceous legumes in Texas aims to promote natural diversity in rangeland restoration as well as to develop agronomic applications for these indigenous species. Agronomic studies of fifteen entries with potential commercial applications indicate a wide range in herbage yield (10 to 120 g/plant/year), crude protein (110 to 210 g/kg), neutral detergent fiber (310 to 520 g/kg), acid detergent fiber (160 to 360 g/kg), lignin (40 to 140 g/kg), and condensed tannin concentrations (3 to 80 g/kg). Wide ranges in forage yields, nutritive value, and anti-quality factors as well as seed production indicate room for numerous agricultural and natural resource applications. Condensed tannins indicate potential for rumen-bypass protein as well as natural gastro-intestinal nematode control in domesticated livestock carrying populations of nematocide-resistant parasites. Similar programs in other Caribbean regions could have equally beneficial local applications without the dangers inherent in introducing potentially noxious, exotic invasives.

ANR 6 - Structural analysis and species composition of tree species associated with coffee in Puerto Rico. M. Arango and E. C. Schröder. Department of Agronomy and Soils, University of Puerto Rico - Mayagüez Campus.

The coffee production system in Puerto Rico is based on a high use of external input (agrochemicals and fertilizers). This is a consequence of the change in policies that led to changing shade-grown coffee to sun cultivation. However, this system brings not only coffee yield declines over time, but also an increase in environmental problems such as soil erosion, reduction in beneficial wildlife and water contamination. The objective of this study was to recognize the shade tree species in the Puerto Rico coffee zone. The field sampling strategy was done in two stages, first a random farm selection in the 22 municipalities with larger areas of shaded coffee, and on-farm selection of a plot for sampling (1,000 m²). Field work was done between June and December 2005 and January and March 2006. Structure and species composition were analyzed. Trees present were inventoried; breadth diameter high (BDH), height and crown area were measured in each plot. The Index of Value of Importance (IVI) was determined; correlation between basal area (BA) and crown area (CA) was calculated with the Proc Corr, and ANOVA was performed and determined by the Proc mixed of the SAS system. The IVI showed the presence of 67 tree species with BDH> 10 cm. The predominant species found were Inga vera, Andira inermis and Citrus sp. with 29.36%, 12.57% and 10.48% of IVI, respectively, and 31.26%, 11.78% and 4.86% of basal area, respectively. The correlation between BA and CA was significant (r=0.56, P<0.0001); there were significant differences among BA of different species at different elevations. These results suggest the favored selection of leguminous trees for coffee shade in Puerto Rico.

ANR 7 - The relationship between soil properties and soil behavior in response to management for agricultural and sporting applications. N. Gordon, G. Eudoxie, and G. Gouveia. University of the West Indies.

Understanding the relationships between soil properties and their performances in relation to supporting plant growth and sporting activities such as cricket is vital in developing sound soil management protocols. Factors such as nutrient content, porosity and water movement and compaction influence root growth and behavior of cricket pitches, respectively. These factors are dictated by soil texture, cation exchange characteristics, pH, organic matter content and the type of management applied to the soil over a period of time. In the Caribbean, with the limited land resources existing, it is crucial that sound and efficient soil management be practiced to guarantee food security as well as to benefit our aesthetic and social needs. A study was therefore conducted at the University of the West Indies in Trinidad with the main aim being to determine the relationships existing between soil properties and their behavior in response to certain management activities, specifically compaction and watering, both of which are essential features in agriculture and sports agronomy. A total of fourteen soils were selected to represent a wide range of pH, clay content, C.E.C, crushing strength, mineralogical properties and salinity. The following tests were done to further shorten the lists of these soils: compaction studies, linear shrinkage, cracking patterns, x-ray diffraction, C.E.C and pH (water and calcium carbonate). Scales were developed from international benchmarks and soils were selected based on their superior properties. Data is still been collected and it is expected that this study will help us understand the management of these soils for both agriculture and sports fields, particularly the preparation of cricket pitches.

Animal Science (ANSC)

ANSC 1 - Evaluación de la prolificidad, comportamiento higiénico y de defensa de la abeja (Apis mellifera), en el núcleo genético de la Regional Norte de República Dominicana. H. A. Almonte, T. Kenol, C. M. De Jesús y R. A. Vásquez. Instituto Superior de Agricultura de la República Dominicana.

El material vivo apícola utilizado en la República Dominicana por los productores no se había evaluado genéticamente y se desconocían los parámetros genéticos de prolificidad, higiene y defensa que son necesarios para su mejoramiento genético. Analizada esta situación, se realizó la evaluación de la prolificidad, comportamiento higiénico y de defensa de la abeja (Apis mellifera) en el núcleo de la Regional Norte de República Dominicana en el año 2005. El propósito de la misma fue seleccionar el mejor material apícola vivo de los productores, el cual servirá de base para una próxima generación de abejas mejoradas. Para realizar esta evaluación, se recolectaron aleatoriamente 20 colmenas entre las mejores de los productores de la Región Norte del país y se evaluaron por seis meses (abril a septiembre 2005). Las variables registradas fueron: comportamiento higiénico y defensivo, prolificidad, enfermedades de la cría y de la adulta, cantidad de celdas reales verdaderas y falsas, alzas de producción. Se realizaron cinco evaluaciones durante las cuales se descalificaron ocho colmenas principalmente por poseer la enfermedad de cría de cal. Se realizó un índice de selección genética con igual ponderación para la prolificidad, comportamiento higiénico y defensivo. Las diferencias registradas estuvieron aseguradas estadísticamente (P≤ 0.05). Las colmenas que mostraron el mayor valor en el comportamiento higiénico fueron 9, 6 y 16. En el índice de mansedumbre resultaron con los tres mayores valores 8, 16 y 9. Sin embargo, las que obtuvieron el mayor índice de selección en prolificidad fueron 9, 16 y 7. Por lo tanto, las tres colmenas con los más altos índices de selección, aptas para ser utilizadas en la formación de una línea genética apícola equilibrada, fueron 9, 16 y 6. Estas reinas deben ser tomadas como base para el mejoramiento genético apícola en República Dominicana, ya que las reinas y zánganos hijos podrían ser multiplicados y diseminados entre los apicultores del país. Se recomienda continuar utilizando la prueba de progenie para lograr una abeja de alto rendimiento, genéticamente equilibrada en prolificidad, mansedumbre y comportamiento higiénico.

ANSC 2 - Efecto de calidad genética en tilapia nilotica (Oreochromis niloticus) sobre la producción de larvas en Higüey, República Dominicana. Y. Dávila, M. García y D. Castillo. Instituto Dominicano de Investigaciones Agropecuarias y Forestales (IDIAF).

Se realizó un estudio con la finalidad de determinar el efecto en dos calidades genéticas de tilapia nilótica (Oreochromis niloticus), una local y otra introducida, sobre la producción de larvas durante 45 días de ciclo. La investigación se condujo en la Unidad Acuícola del Campo Experimental Higüey del Instituto Dominicano de Investigaciones Agropecuarias y Forestales (IDIAF) en la provincia La Altagracia, en el periodo correspondiente al II ciclo de desove de tilapia, entre los meses de octubre y noviembre del 2005. Se utilizó un diseño completamente al azar con dos tratamientos: TI = Tilapia local o CIMPA, y TII = Tilapia introducida o IDIAF, con cinco y seis repeticiones, respectivamente. Las unidades experimentales fueron once estanques de 375 m². Se utilizó una proporción sexual de 1.5:1 (hembras: macho) para una densidad de siembra de 0.5 ej /m² y un peso promedio de 61 y 60 g, respectivamente. La variable medida fue la producción de larvas, contabilizada por el método volumétrico descrito por Vásquez y col. (1988). Se encontraron diferencias significativas entre los tratamientos. Para la variable dependiente producción total, el tratamiento II (media = 160283) superó significativamente (prob>t= 0.0036) al tratamiento I (media = 132687), valor t = -3.91. Se concluye que la tilapia introducida IDIAF superó significativamente a la tilapia local CIMPA, produciendo por cada larva de tilapia local 1.5 de la tilapia introducida. Se caracterizaron las poblaciones de la siguiente manera: heredabilidad alta o buena calidad genética para la tilapia introducida IDIAF y heredabilidad baja o mala calidad genética para la tilapia local CIMPA.

ANSC 3 - Influencia de la alimentación con pollinaza fresca o fermentada en la incidencia de parásitos gastrointestinales en ovinos de engorde. S. A. Mena, V. De Jesús, D. Gelabert, F. Villamil y J. Bueno. Instituto Superior de Agricultura (ISA) de la República Dominicana.

Desde la década de los 80s, en la República Dominicana se ha promovido el uso de la pollinaza como opción para alimentar rumiantes. Eso ha originado un vasto uso del subproducto por parte de los productores en tiempo de sequía. Hoy en día por asuntos de bioseguridad alimentaria se ha venido cuestionando dicho uso. Se ha pensado que por la pollinaza contener heces fecales podría ser un vehiculo de infección parasitaria de los animales que la consuman. Se realizaron dos ensayos en que se cuestionó la incidencia en la carga parasitaria de ovinos de engorde consumiendo pollinaza como complemento en su dieta. En el primer ensayo, que duró 84 días, se analizaron las heces de ovinos alimentados con y sin pollinaza, los cuales habían sido desparasitados previamente con Ivermectina. El uso continuo de pollinaza en la dieta de estos animales no influyó en su infestación por parásitos. Al final del ensayo ambos grupos presentaron un buen estado general de salud. En un segundo ensayo con 18 ovinos, divididos en tres grupos, en los que se valoró la utilización de pollinaza fresca o fermentada contra un testigo con alimento balanceado, la ganancia diaria, eficiencia alimenticia y peso vivo final fue similar en ambos grupos y significativamente diferente al testigo. El examen post- mortem de los ovinos que consumieron pollinaza fresca o fermentada reportó la presencia de H. cortatus a nivel del abomaso, no así en el testigo. Este parasito estuvo presente en los animales del primer ensayo, estuvieran consumiendo o no pollinaza fresca. En ambos trabajos se concluyó que no hay una relación directa entre la infección parasitaria del animal y el consumo de pollinaza.

ANSC 4 - Genotyping of a Hind III RFLP at the IGFBP-2 locus in bulls divergently selected for serum IGF-I and its effects on carcass and meat quality traits. M. Pagán¹, K. Kizilkaya², M.E. Davis³, N.E. Raney⁴, and C.W. Ernst⁴. ¹University of Puerto Rico - Mayagüez Campus, ²Adnan Menderes University, Aydin, Turkey, ³The Ohio State University, Columbus, ⁴Michigan State University, East Lansing.

The effect of line (high, HL vs. low, LL), season-year [fall 98 (F98) and spring 99 (S99)] and IGFBP-2 genotype (alleles identified by the endonuclease Hind III and labeled A and B) on hot carcass weight (HCW), corrected backfat (CBFT), ribeye area (RA), kidney, pelvic and heart fat (KPH), marbling content (MB), yield grade (YG), quality grade (QG), and cutability (CUTA) were evaluated in Angus bulls divergently selected for serum insulin-like growth factor-I (IGF-I) concentration (n=60). In this group of animals, allele frequencies were 0.27A/0.73B and 0.36A/0.64B in F98 and S99, respectively, and a significant effect of genotype was found for QG. Bulls of AA genotype had higher QG than AB or BB bulls. For this trait, a higher value was observed in S99 (P<0.01). A significant interaction between genotype and season-year was observed for CBFT, MB, YG, and CUTA (P<0.02). In F98, the AA genotype had more MB than both AB and BB. However, MB was higher in S99 BB bulls when compared to the AB and BB bulls from F98. Moreover, AB animals tended to have lower means for MB in F98 (MB = 3.66) than in S99 (MB = 4.40; P<0.09). In terms of YG, the S99 heterozygous calves were superior to the F98 AB and BB calves. Also S99, BB bulls were superior in YG to animals of the same genotype from F98. In addition, in F98, AB and BB animals were similar in CUTA, but superior to AB animals from S99. A significant interaction between line and season-year was observed for RA and KPH (P<0.03). In HL, S99 calves had higher RA than F98 calves. Also, S99 HL calves had higher RA than LL calves in F98 and S99. Even though KPH did not differ among F98 and S99 in HL and S99 LL, it was lower in F98 LL. These results indicate that the usefulness of IGFBP-2 as a genetic marker for carcass and meat quality within this unique cattle population is influenced by environmental factors related to the year and season of birth.

ANSC 5 - Digestibilidad "in situ" y parámetros químicos de ensilaje de maíz (Zea mays) fresco, prehenificado y prehenificado con urea utilizando ovinos. A. Santana, E. Blanco y R. Batista. Instituto Superior de Agricultura (ISA) de la República Dominicana.

En la República Dominicana la disponibilidad de forrajes frescos está influenciada por los periodos de lluvias y sequía que se registran en el área. Una necesidad apremiante en la producción ganadera lo constituye la práctica de conservar forrajes. Por otro lado, se tiene una gran cantidad de subproductos de cosechas agrícolas. Como opción para el aprovechamiento a largo plazo de esos subproductos está la posibilidad de utilizarlos ensilados para alimentar ganado, específicamente como una fuente de fibra en la ración de rumiantes. Tomando en consideración ambas situaciones se realizó un ensayo para determinar la composición química, digestibilidad y tasa de degradación de maíz ensilado fresco, prehenificado y prehenificado con urea. La metodología usada fue la de bolsas ruminales. Se utilizaron dos ovinos fistulados al rumen en los que se infundieron muestras de los forrajes y se retiraron en un horario de 3, 6, 9, 12 y 24 horas. Se realizaron tres repeticiones en el tiempo. Se determinó proteína cruda, fibra detergente ácida y fibra detergente neutra a las muestras antes y después de la infusión. Los datos obtenidos para digestibilidad y tasa de degradación del maíz fresco fueron 60.98% y 0.0067 g/h; prehenificado, 56.16% y 0.0063 g/h; y prehenificado con urea, 63.98% y 0.0075 g/h. Se concluye que los mejores resultados obtenidos fueron con el ensilaje de maíz prehenificado con urea, como expresión de la calidad nutricional del mismo ya que presentó mayores porcentajes de proteína cruda, con 12.42%, comparado con 8.31% del maíz fresco y 5.46% del prehenificado.

ANSC 6 - Efecto de la adición de Avizyme^® en la dieta sobre el desempeño productivo y la composición de la canal de gallinas de guinea (Numida meleagris). H. L. Santiago, J. A. Orama y A. A. Rodríguez. Departamento de Industria Pecuaria, Universidad de Puerto Rico, Estación Experimental Agrícola.

Estudios recientes han demostrado beneficios de la suplementación de enzimas, como proteasas y amilasas, en dietas para pollos parrilleros utilizando maíz y harina de soya como ingredientes principales. Sin embargo, no se puede extrapolar estos beneficios a la producción comercial de otras especies de animales domésticos. Con el objetivo de determinar el efecto de la adición del producto Avizyme^® (AV) en dietas para gallinas de guinea, 600 pollos de guinea de un día de edad se asignaron al azar a cuatro tratamientos con 10 repeticiones de 15 aves por jaula y se criaron hasta la edad de mercado (84 d) en un galpón de cría convencional. Los tratamientos consistieron en dietas con diferentes niveles de inclusión de AV (0, 0.25, 0.50 y 0.75%). Las aves y el alimento se pesaron semanalmente hasta los 84 días de edad para determinar el peso corporal (PC), consumo de alimento (CA) y la conversión de alimento (CAL). La mortalidad y las aves rezagadas (AR) se removieron y pesaron periódicamente. A los 84 días de edad, 50 aves por tratamiento se seleccionaron al azar y se procesaron para evaluar la composición de la canal. Se obtuvieron los pesos para canal estilo “New York Dress” (NYD), canal eviscerada (CE), y grasa abdominal (GA) y los rendimientos se calcularon como un porcentaje del peso vivo. No se observaron diferencias significativas entre tratamientos para mortalidad, AR, PC, NYD, CE, y GA. A partir de la cuarta semana de crianza, dietas conteniendo AV resultaron con CA y CAL similares entre sí, pero significativamente menores a la dieta control. Tampoco se observaron diferencias significativas entre dietas para los rendimientos de NYD, CE y GA. Se puede concluir que la adición de al menos 0.25% de AV a dietas de gallinas de guinea basadas en maíz y harina de soya tiene un efecto positivo en la conversión de alimento, sin detrimento en la composición de la canal y el peso de mercado.

Crop Protection (CP)

CP 1 - Biological attributes of chilli thrips, Scirtothrips dorsalis Hood, on four crops. D. Seal and W. Klassen. University of Florida.

The chilli thrips, Scirtothrips dorsalis Hood, is an important pest of fruits, ornamentals and vegetables. Various insecticide trials have been conducted in St. Vincent and the Grenadines to control this pest. Pylon, Spintor and Agrimek provided significant control of this pest. In order to efficiently manage this pest, knowledge about biological attributes of this pest on various crops is essential. In the present study, chilli thrips development was studied on pepper, eggplant, bean, tomato and squash.

CP 2 - Control químico de la mosca (Melanagromyza obtusa Malloch) de la vaina del guandul (Cajanus cajan L. Millspaug). J. R. Cedano, Y. Segura y S. Nova. Instituto Dominicano de Investigaciones Agropecuarias y Forestales (IDIAF).

La mosca de la vaina del guandul cuando no es controlada puede dañar entre un 60 y 80% de la producción, reduciendo la rentabilidad del cultivo. Con el objetivo de contribuir a su control en el Valle de San Juan en la República Dominicana, se evaluaron siete insecticidas en el año 2003. Se utilizó un diseño de bloques completos al azar con cuatro repeticiones y ocho tratamientos que consistieron en los insecticidas de contacto: ciromazina (125 g/ha), cipermetrina (150 ml/ha), ciflutrina (850 ml/ha), organofosforado (625 ml/ha); sistémicos: dimetoato (800 ml/ha) e imidacloprid (64.0 g/ha) y dimetoato + cipermetrina (325 ml/ha) y un testigo (sin aplicación). Las variables evaluadas fueron el porcentaje de daño, el rendimiento comercial en verde y la rentabilidad. Los tratamientos se aplicaron tres veces desde la prefloración a intervalos de 12 días. Para el análisis estadístico se utilizó el paquete de SAS y prueba de contrastes ortogonales y para el análisis de rentabilidad se empleó el método de presupuesto parcial del Centro Internacional de Mejoramiento de Maíz y Trigo (CIMMYT). El porcentaje de daños fue un 27% menor en los tratamientos que recibieron insecticidas, en contraste con el testigo (P < 0.0001). Los daños fueron menores en un 10% cuando se aplicaron insecticidas sistémicos, en comparación con los de contacto (P = 0.0001). El efecto fue menos significativo (P = 0.012) cuando se combinó el dimetoato con la cipermetrina y se redujo en 9%. Dentro de los insecticidas sistémicos el dimetoato presentó pérdidas menores (6%) que el imidacloprid (P = 0.018). Para el rendimiento comercial en verde se encontraron diferencias significativas entre el testigo y la aplicación de insecticidas (P = 0.0039), resultando el testigo superado en 1,739 kg/ha. El mayor beneficio neto (RD$78,282/ha) se obtuvo con ciflutrina, con una tasa marginal de retorno de 1,463%; seguido por la ciromazina que tuvo un beneficio neto de RD$71,917.00 y una tasa marginal de retorno de 1,339%.

CP 3 - Mitigating the impact of bacterial wilt and bacterial spot on tomatoes by integrated and biorational approaches. P. Ji, F. B. Iriarte, M. T. Momol, S. M. Olson, and J. B. Jones. University of Florida.

Bacterial wilt and bacterial spot, caused by Ralstonia solanacearum (Rs) and Xanthomonas spp., respectively, are important diseases of tomatoes in many areas of the world, including the Caribbean region. To develop biorational approaches for managing bacterial wilt, new biofumigants and cover crops were used to reduce soil populations of Rs. Bacteriophages were used as biocontrol agents for bacterial spot, and plant systemic resistance inducers were used to enhance plant resistance against both bacterial spot and wilt. A biofumigant, thymol, was effective in reducing bacterial wilt on tomato when used as preplant soil fumigation through drip irrigation lines. Thymol applied in conjunction with acibenzolar-S-methyl (ASM) significantly reduced bacterial wilt compared with thymol or ASM applied alone. Sorghum-sudan and rye used as cover crops reduced soil population of Rs in field plots. Application of phages significantly reduced bacterial spot severity under greenhouse and field conditions whenever a susceptible host was present. Formulated phages were more effective than non-formulated phages and less affected by environmental stress such as desiccation, temperature and UV effect. Whereas phage populations were reduced when a copper bactericide was applied the same day as the phage, there was minimal or no effect when phage was applied three or more days prior to copper application. Application of phages in conjunction with ASM was more effective in suppression of bacterial spot than the treatments applied alone. Results from these studies provide strong evidence that several biorational products effectively control bacterial wilt and bacterial spot and that integrated use of these approaches was shown to be feasible for managing these diseases in tomato production.

Keywords: Ralstonia solanacearum, Xanthomonas spp, Biorational alternative

CP 4 - Entomology training and education opportunities in the National Plant Diagnostic Network (NPDN). A. Hodges. University of Florida.

The National Plant Diagnostic Network (NPDN), formed in June 2002 by USDA-CSREES, is concerned with protecting U.S. agriculture by promoting the early detection of exotic pests. The NPDN primarily links land grant universities (LGUs) nationwide, but also appropriately networks and communicates with state and federal regulatory officials. The NPDN is divided into five regions based on geography and crop similarity. A majority of NPDN's efforts have focused on plant pathology-related activities because of the USDA's select agent list and costs associated with plant pathology diagnostics. Nonetheless, entomology has been integrally incorporated into the NPDN. Efforts to incorporate entomology in the network primarily include 1) intensive taxonomic workshops for identifiers and extension specialists and 2) first detector or field-based identification training for exotic pests of concern. Training opportunities provided by the NPDN have resulted in new pest records, increased networking with taxonomic specialists for identification confirmations, and sample submission of high-risk pests of concern.

Keywords: National Plant Diagnostic Network, Exotic insects, Taxonomic training

CP 5 - Influencia de la fumigación de suelos sobre la residualidad en el suelo de 2,4-D y dicamba y su efecto en tomate. J. P. Gilreath, B. M. Santos, C. A. Chase y S. J. Locascio. Gulf Coast REC, IFAS, University of Florida.

Se realizaron dos ensayos en Bradenton, Florida, EE.UU., para evaluar el efecto de la fumigación de suelos sobre la persistencia en el suelo de los herbicidas 2,4-D y dicamba y sus efectos en el crecimiento y rendimiento de tomate (Lycopersicon esculentum). Los herbicidas se aplicaron en varias dosis entre 0 y 2.28 kg/ha en suelos fumigados con bromuro de metilo y en suelos sin fumigar. Los resultados indicaron que los mayores niveles de toxicidad y pérdidas de rendimiento ocurrieron con dicamba en los suelos fumigados, lo cual puede atribuirse a la eliminación de microorganismos del suelo que metabolicen los herbicidas.

CP 6 - Characterization of Phytophthora capsici on diverse hosts, its survival and management. P.D. Roberts, E.R. Marquez, and R.D. French-Monar. SWFREC, University of Florida.

A cooperative research project between the University of Florida and the University of Puerto Rico investigated the occurrence, epidemiology, and management of the oomycetic pathogen, Phytophthora capsici. Significant losses due to this disease consistently occur in bell pepper and summer squash production in south Florida. Outbreaks on other vegetable crops include tomato, eggplant, cantaloupe, cucumber, pumpkin, and watermelon. In Florida, isolates of P. capsici from different production regions were compared by characteristics such as pathogenicity, mating type, and resistance to mefenoxam. The variation in the pathogenicity of P. capsici isolates was examined on four vegetable hosts: pepper, summer squash, tomato and watermelon. The pathogen's ability to survive in the soil type and agricultural system of south Florida was examined and our data suggests that the survival of oospores and other propagules easily spans the short summer fallow period. P. capsici was recovered from tailwater and retention ponds in southwest Florida suggesting another potential source of inoculum. Field sampling of common weeds found three species which harbored the pathogen. Control of the disease by chemicals is difficult because of the rapid rate of development of the disease, especially under ideal environmental conditions, and insensitivity to fungicide. Components of an integrated, multi-tactic management program including cultural, chemical, and biological control methods were examined in field studies. Results obtained in Florida are serving as the basis for similar research in Puerto Rico. This project has led to a greater understanding of the variability, survival and management of this disease.

CP 7 - Population dynamics of the exotic coffee leafminer parasitoid, Mirax insularis Muesebeck, in a sunlight coffee plantation in Puerto Rico. F. Gallardo. Crop Protection Department, University of Puerto Rico, Agricultural Experiment Station.

A field study was conducted in a sunlight coffee grove of Puerto Rico to determine the population dynamics of Mirax insularis Muesebeck, the coffee leafminer [Leucoptera coffeella (Guérin-Méneville)] larvae parasitoid. Coffee leaf samples were collected monthly starting in early spring and finishing in late winter of 2005. The highest parasitism ratio (0.2095) was recorded during August, followed by that of December with 0.1971. The lowest parasitization ratio (0.0120) was obtained in November. The average parasitism percentage obtained during the study was 20.13. Although the parasitism ratio was very low from April to July, in August when the coffee leafminer (CLM) population peaked, M. insularis also increased exponentially. However, from September to November a dramatic decrease in the parasitism ratio was observed. Heavy rains occurred during that season decreasing the CLM population and thus affecting the viability for suitable larvae for parasitization.

Keywords: Leucoptera coffeella, Coffee leafminer, Mirax insularis, Parasitism

CP 8 - Effectiveness of poultry litter for the control of plant-parasitic nematodes on tropical crops. J. A. Chavarría¹, N. Vicente¹; J. Ortiz², and C. Flores³. ¹Department of Crop Protection, ²Department of Agricultural Economics and, ³Department of Horticulture. University of Puerto Rico, Agricultural Experiment Station.

Traditional management strategies for plant-parasitic nematodes are based on chemical pesticides. However, recently some of these chemicals have been banned because of environmental risk and food safety. Alternative practices to the use of broad-spectrum synthetic pesticides for the management of phytonematodes in high value tropical crops are receiving increasing attention. Research was conducted to determine the effects of poultry litter on the management of phytonematodes associated with plantain (Musa acuminata X M. balbisiana) and pumpkin (Cucurbita moschata). The amendment was applied to nematode-infested soils at rates ranging from 0 to 14.5 kg/plant; also a treatment with phenamiphos at 1.5 g a.i/plant was included to determine the effectiveness of the amendment. Results indicated that poultry litter is effective in reducing final soil and root populations of Radopholus similis, Meloidogyne incognita, Rotylenchulus reniformis and Helicotylenchus multcinctus, when compared with the chemical control. Also, the amendment improved plant development, root condition and crop yield (e.g., number of hands and fruits per bunch, and bunch weight of plantain; number of fruits and yield of pumpkin). The use of poultry litter as a soil amendment represents a suitable ecological alternative for nematode management and waste disposal in Puerto Rico.

CP 9 - Head capsule width as an instar indicator for larvae of the coffee leafminer Leucoptera coffeella (Guérin-Méneville) (Lepidoptera: Lyonetiidae). P. Navarro and F. Gallardo. Department of Crop Protection, University of Puerto Rico, Mayagüez Campus.

The objective of this study was to determine the number of instars of the coffee leafminer, Leucoptera coffeella (Guérin-Méneville), based on the distribution of head capsule widths of the larvae. Larvae head capsules from field coffee leaf samples (Adjuntas, Guilarte, Yauco, Río Prieto, Consejo and Helechales) were measured under microscopy across their widest point. The results were plotted and analyzed against observed frequencies. Six instars were observed, taking as reference the Dyar’s rule, where a factor of 1.4 was considered. From February to March, the last two instars were the ones most frequently found in the field. This information, as reference to liberations of parasitoids that prefer late instars can be used for biological control of the coffee leafminer.

CP 10 - Genetic analysis of resistance to bacterial spot in solanaceous crops with molecular markers. C. E. Vallejos¹, V. Jones¹, G. Minsavage², D. Schultz¹, R. Rodrigues³, J. B. Jones², and R. E. Stall². ¹Deptartment of Horticultural Sciences and ²Department of Plant Pathology, University of Florida. ³Department of Crop Science and Plant Breeding, Universidad e Estadual do Norte Fluminense, Brasil.

Xanthomonas campestris pv. vesicatoria is the causative agent of bacterial spot, a major disease of tomatoes and peppers in tropical and sub-tropical production regions. Development of resistance to copper and streptomycin in the various strains of this pathogen has left genetically determined disease resistance as the only effective method of control. Fortunately, sources of resistances to races T2 and T3 in tomato, and to races P4 and P6 in pepper have been identified. We have used tomato markers to identify the map location of the resistance loci. This work was conducted in several steps. First, we used the markers to survey the genomes of these species for polymorphisms. Then, we generated segregating progenies between susceptible and resistant genotypes, screened them with the appropriate strain, and analyzed the linkage relationships between the resistance loci and the segregating molecular markers. Markers that are tightly linked to resistance loci can be used for marker-assisted selection in breeding programs.

Keywords: Resistance, Xanthomonas, Linkage analysis, Marker assisted selection

CP 11 - LC, un atrayente a partir de material disponible en la República Dominicana con diferentes niveles del aditivo Bórax para capturar moscas de la fruta. F. R. Ogando y C. A. Serra. Instituto Dominicano de Investigaciones Agropecuarias y Forestales (IDIAF/UNPHU)

Para desarrollar un atrayente local efectivo y de bajo costo para el manejo de moscas de la fruta, se realizó un estudio en una plantación de mango (Mangifera indica L.) en la “Quinta La Cabuya”, Hato Damas, San Cristóbal, República Dominicana, del 30 de julio al 22 de septiembre de 2005. La LC es una proteína hidrolizada que se mezcló al 5% (p/p) con Borato de Sodio (sal de bórax). Se usó el diseño de bloques al azar con cinco repeticiones y cuatro tratamientos: T1 = (testigo) atrayente estándar Torula/Bórax (BWM, E.U.A.), T2 = LC+0% Bórax (B), T3 = LC+1% B. y T4 = LC+2% B. Las trampas tipo MultiLure® (BWM) se colocaron espaciadas a ≥ 25 m, a alrededor de 2 m de altura. Las trampas se evaluaron y se rotaron semanalmente, determinándose la cantidad y sexo de las moscas capturadas. En promedio, en las capturas durante el período, el T1 no superó significativamente al T4, pero éstos superaron al T2 y éste a su vez al T3 (α=0.002***). Como anteriormente establecido por Serra et al. (2005), existe una correlación significativa entre el contenido de bórax del atrayente y las capturas de A. obliqua (Macq.) en mango. En un segundo ensayo comenzado el 10 de noviembre de 2005 en una plantación de guayaba (Psidium guajava L.) en la Estación Experimental de Frutales de Baní (EEFB), Villa Sombrero, se compararon seis tratamientos: T1=Torula/Bórax (testigo), T2=3.3% LC+2% B., T3=3.3% LC+2.7% B., T4=5% LC+2% B., T5=6.7% LC+1.3% B. y T6=6.7% LC+2% B. Los resultados preliminares indican que las moscas atrapadas, a un nivel muy inferior al primer ensayo, fueron casi exclusivamente A. suspensa (Loeb) y que el estándar (T1) fue superado por el T3, mientras que una reducción del contenido de bórax no mejoró las capturas, aún aumentando la dosis del LC.

Palabras Clave: Anastrepha spp., Trampeo, Atrayentes, Proteína hidrolizada, Mangifera indica, Psidium guajava

CP 12 - Plantas hospederas de la mosca asiática, Melanagromyza obtusa (Malloch) (Diptera: Agromyzidae), y susceptibilidad de variedades tradicionales de guandul. C. A. Serra, S. García, J. Arias y Y. Segura. Estación Experimental Mata Larga (EEML), San Francisco de Macorís, Estación Experimental Arroyo Loro (EEAL), San Juan de la Maguana, Programa Nacional de Protección Vegetal, CENTA, Instituto Dominicano de Investigaciones Agropecuarias y Forestales (IDIAF).

Ante la ausencia de enemigos naturales efectivos, moscas asiáticas del guandul (MAG), reportadas en el Hemisferio Occidental (República Domonicana y Puerto Rico) a partir del 2000, pudieron dañar entre un 20 y 85% de las semillas (Serra et al., 2003). Entre mayo del 2004 y septiembre del 2005 se realizó un estudio, financiado por USDA/APHIS, que consistió en recolectar plantas con características morfológicas de hospederos potenciales (con vainitas o cápsulas) en el Valle de San Juan de la Maguana y otras zonas del país. Además, se realizaron infestaciones con moscas asiáticas de plantas de 20 especies seleccionadas en jaulas en la EEML y EEAL. En los materiales de más de 30 especies provenientes de campos del Sur solamente se detectaron MAG a parte del hospedero principal C. cajan, frijolillo [Rhynchosia minima (L.) DC.] y Flemingia macrophylla (Willd.) O. Kze. (en Provincia Samaná), pero no en camarones [F. strobilifera (L.) R.Br.] (todas Leguminosae-Papilionoideae). Con la metodología empleada para las infestaciones en jaulas, solamente resultaron positivos como hospederos C. cajan y R. minima, pero no así el molondrón [Abelmoschus esculentus (L.) Moench, Malvaceae], cuatro variedades de cártamo (Carthamus tinctorus L., Asteraceae), seis variedades glabras o pelosas de soja (Glycine max Merr.), habichuela (Phaseolus vulgaris), haba (P. lunatus L.), caupí [Vigna unguiculata (L.) Walp.], frijol mungo (V. radiata (L.) Wilczek), Clitoria ternatea L., Macroptilium lathyroides (L.) Urb. (todas Leguminosae-Papilionoideae) y otras especies cultivadas y silvestres. Las tasas de infestación de vainas de guandul en la EEML variaron dependiendo de la época del año, exposición a sombra y las variedades comparadas (UASD, Desatalío, Kaki, 7x7); sin embargo, los datos no permiten conclusiones definitivas.

Palabras Clave: Melanagromyza obtusa, Plantas hospederas, Cajanus cajan, República Dominicana

CP 13 - Efecto de Beauveria bassiana sobre la mortalidad del picudo Cosmopolites sordidus Germ. y Metamasius hemipterus en banano orgánico. R. Taveras y A. Cuevas. Universidad Autónoma de Santo Domingo.

El banano orgánico se ha convertido en un producto de importancia económica para el país. El 70% del banano orgánico que consume la Unión Europea es producido en República Dominicana. El picudo negro del plátano C. sordidus Germ. es una de las plagas más temidas por los productores a nivel mundial con pérdidas que van desde 3 a 90%. El presente estudio se realizó en una finca orgánica de banano con fines de exportación perteneciente a una zona de vida de bosque seco subtropical. Para determinar el efecto se utilizó un diseño de bloques completamente al azar con dos tratamientos (dos formulaciones semi-artesanales del hongo B. bassiana; una presentación sólida, tal y como sale del proceso de producción y la formulación líquida) y un testigo. El tratamiento que provocó mayor mortalidad lo constituyó la formulación sólida, con un 45.79% de mortalidad, seguido por el tratamiento líquido, con un 30.96%, y por último el testigo, con 15.96%. Esta información contribuye con el desarrollo de estrategias de manejo orgánico del cultivo

Palabras Clave: Banano orgánico, Beauveria bassiana, Metamasius hemipterus, Cosmopolites sordidus Germ.

CP 14 - Chilli thrips (Scirtothrips dorsalis) (Thysanoptera: Thripidae) in Barbados, a new pest of sea island cotton. B. M. Taylor, I. H. Gibbs, and M. A. Ciomperlik. Ministry of Agriculture and Rural Development, Christ Church, Barbados, USDA APHIS CPHST Pest Detection Diagnostics and Management Laboratory, Edinburg, TX.

Surveys were conducted in 2005 and 2006 in Barbados to determine the presence and distribution of Scirtothrips dorsalis, a recent invasive thrips pest species new to the Western Hemisphere. This paper documents the establishment of the thrips pest in Barbados, and shows that it is distributed in most of the parishes where typical vegetable cropping occurs. Population densities of S. dorsalis are lower than those observed previously on other Caribbean islands, indicating that it may have been more recently introduced. Hot peppers (Capsicum chinensis) appear to be widely affected throughout the island; however, there is little evidence at this time of significant economic impact to that crop. Sweet pepper (Capsicum annuum), beans (Phaseolus vulgaris), carrots (Daucus carota sativus), and eggplant (Solanum melongena) showed the presence of both adults and larvae of S. dorsalis as well. Samples obtained from sea island cotton (Gossypium barbadense) in the 2005 and 2006 surveys indicate that chilli thrips reach very high population levels in this crop. Damage symptoms are bronzing of the upper leaf surface, stunting, slight curling, and leaf drop. Ongoing research focuses on monitoring methods, seasonal population trends, and effective insecticidal treatments to control the thrips.

CP 15 - Effect of virtually impermeable films on metam, chloropicrin, and 1,3-dichloropropene efficacy on nutsedge populations. J. P. Gilreath, B. M. Santos, M. N. Siham, P. Vaculin, and M. Herrington. Gulf Coast REC, IFAS, University of Florida.

Previous research has demonstrated stimulation of purple and yellow nutsedge (Cyperus rotundus and C. esculentus) with chloropicrin when applied at rates ranging from 100 to 150 lb/acre (112 to 168 kg/ha) under low or high density polyethylene film mulch. This stimulatory effect has been exploited in research by developing a program of metam application five days after application of chloropicrin, thus placing metam in the soil once the tubers have begun to sprout and are most vulnerable. This project was expanded in 2004-05 to include the commercial emulsifiable concentrate formulation of 65% 1,3-dichloropropene and 35% chloropicrin (1,3-D + Pic) and virtually impermeable film mulch as well as high density polyethylene film. The test site was a commercial tomato farm in west central Florida with a heavy infestation of purple nutsedge. Chloropicrin was applied into raised beds through three gas knives, while 1,3-D + Pic and metam potassium were applied in 1 acre inch of water through two drip irrigation tubes spaced 10 inches apart and five inches from the bed center. Metam was applied five days after application of chloropicrin and 1,3-D + Pic. Treatments were applied under both standard high density polyethylene film (Hilex® and Bromostop®) and VIF. Stimulation of nutsedge sprouting and emergence was approximately the same with either chloropicrin alone or combined with 1,3-D; however, there was some enhancement when applied under VIF. There was a slight improvement in efficacy of metam potassium when applied alone under VIF, contrary to previous results. Application of metam five days after application of chloropicrin or 1,3-D + Pic greatly improved nutsedge control over that observed without the subsequent application of metam, and VIF improved results to some degree. Producers of drip-irrigated crops in Florida can achieve acceptable to excellent nutsedge control using this sequential application technique combined with VIF; however, the addition of a second drip tube on the bed top increases expense by approximately US$125/acre and is not compatible with crops grown with more than a single row on the bed.

CP 16 - A participatory research and development study with fairtrade banana farmers for watergrass control using cover crops. W. A. Isaac, W. Ganpat, R. Brathwaithe, and I. Bekele. Ministry of Agriculture, Trinidad and Tobago.

A major constraint of fairtrade banana farmers in St. Vincent is the management of watergrass (Commelina diffusa). Farmers are constrained to find safe non-chemical solutions to this problem because of concerns of the importers in Europe regarding health and the environment. The objective of the study was to evaluate the Participatory Research and Development methodology with resources of poor farmers operating under conditions of limited research and little extension technical support. A 3-day workshop was held with all stakeholders (farmers, extension officers, administrators, input suppliers, and researchers). Farmers were exposed to the essentials of systematic research through a process of experiential learning and using a variety of participatory tools and techniques, including matrix ranking and simulations. At the end of the workshop, 33 farmers agreed that they would test, on thier own farms, three cover crops. The current farmer practice served as the control. The cover crops evaluated were Desmodium heterocarpon, Mucuna pruriens and Arachis pintoi. They also designed the trial, agreed on data to be collected and the form of the analysis. The paired treatment design was used, and each farmer selected at random the treatment(s) (no more than two) that each would test on–farm. At least six farmers carried out the same treatment pairs which constituted the replicates in the experiment. Over a six-week period, farmers established the experimental plots, applied the treatments and collected and recorded data weekly. Summary data were subjected by the farmers to the Overlap test. This farmer-friendly and graphic test, used to evaluate differences among the treatments, is comparable to the t-test used in traditional research. Results showed that one treatment, Desmodium heterocarpon, was significantly better than the others in controlling the watergrass weed. The participatory research and development methodology holds promise as a methodology for small farmers to take an active part in solving other farm-related problems. Farmers have expressed confidence and competence to carry out the process once again. The lessons learnt and constraints to this approach are outlined in the paper. Plans for scaling up the project in other Eastern Caribbean banana-producing islands are also discussed.

CP 17 - Influencia de la desfoliación sobre el comportamiento del plátano (Musa AAB) y el manejo de Sigatoka negra (Mycosphaerella fijiensis Morelet). D. Ozuna, H. Ricardo y E. De Jesús. Instituto Dominicano de Investigaciones Agropecuarias y Forestales (IDIAF).

Para manejar la Sigatoka negra en las plantaciones de plátano, el deshoje fitosanitario es la principal práctica con que cuentan los productores para reducir el inóculo, su incidencia y severidad. El propósito del estudio fue identificar las etapas del plátano (Musa AAB), clon Macho por Hembra Verde, más tolerantes a la desfoliación severa. La investigación se realizó entre mayo de 2002 y mayo de 2003 en el paraje Sabana Toro, San Cristóbal (18° 25’ Norte y 70° 6’ Oeste y altitud de 43 msnm). Se utilizó un diseño de bloques completos al azar con cuatro repeticiones y seis tratamientos, los cuales fueron dejar la planta con siete hojas en las emisiones de hojas de doce a veintiuna, de veintiuna a veintisiete, de veintiuna a floración, de veintiocho a floración, a floración, y el testigo (desfoliación natural). Las variables medidas fueron peso de racimo, número de frutos por racimo y promedio ponderado de infección a la floración y la cosecha. Se realizó un análisis de varianza y la separación de medias por Duncan. Las desfoliaciones se efectuaron cada semana. El peso del racimo fue diferente (P=0.0017), no así el número de frutos por racimo (P=0.07). El promedio ponderado de infección de los tratamientos fue diferente, manteniendo el mismo nivel de significación a la floración y la cosecha (P=0.0001). Los racimos fueron más pesados cuando en la planta ocurrió una desfoliación natural (12.57 kg), y cuando se dejaron con siete hojas a la floración (12.22 kg) o entre la emisión de las hojas veintiuna a veintiocho (11.97 kg). Los tratamientos dejados con siete hojas entre la emisión de hojas veintiuna a floración y hojas veintiocho a floración presentaron menor promedio ponderado de infección al momento de la floración y la cosecha. El plátano se comercializa en el país por fruta. A pesar de mostrar el promedio ponderado de infección más alto a la cosecha, el tratamiento con desfoliación natural parece ser el recomendado para el manejo de la Sigatoka negra ya que la cantidad de frutos en el racimo no fue diferente a la de los demás tratamientos, y sus racimos fueron de los más pesados.

CP 18 - The impact of Amitus hesperidum, an exotic parasitoid wasp, on population levels of citrus blackfly, Aleurocanthus woglumi (Homoptera: Aleyrodidae). C. Shripat and K. Parkinson. Ministry of Agriculture, Land and Marine Resources, Trinidad and Tobago.

A classical biological control programme was initiated in Trinidad in June 2000 to manage Citrus blackfly (CBF), Aleurocanthus woglumi (Homoptera: Aleyrodidae), through introduction of the exotic natural enemy Amitus hesperidum (Hymenoptera: Platygasteriade). The pest and exotic natural enemy were monitored at three sites in Cumuto, Freeport and Penal. Observations were made at 6-month intervals over a four-year period from February 2000 to August 2004. A. hesperidum became established within one year of its release and exerted control on A. woglumi as evidenced by the reduction in population levels of the pest from 74% to 13% over the three locations. During the last three years of the study pest populations were maintained at low levels ranging from 13% to 3%. The findings suggest that A. woglumi has successfully been controlled by A. hesperidum four years after initial releases of the parasitoid at Cumuto, Freeport and Penal.

Keywords: Citrus blackfly, Aleurocanthanus woglumi, Amitus hesperidum, Parasitoid wasps, Population levels

CP 19 - Variación estacional en la fotodegradación de paraquat aplicado sobre coberturas plásticas. J. P. Gilreath, B. M. Santos y S. J. Duranceau. Gulf Coast REC, IFAS, University of Florida.

Se condujeron estudios en Bradenton, Florida, EE.UU., para determinar el efecto de la estación del año, tiempo de exposición a luz solar y color de cobertura plástica sobre la fotodegradación de paraquat. Los ensayos se establecieron en invierno, primavera y verano con coberturas blancas y negras de polietileno, las cuales se expusieron a 1, 4, 8, 24, 30, 48, 72, o 96 h de luz solar después de la aplicación del herbicida. La interacción entre la estación del año, color de la cobertura y tiempo de exposición fue significativa para la cantidad de paraquat restante sobre las coberturas. La fotodegradación de paraquat fue más baja en invierno que en las otras estaciones. A las 48 h de exposición solar, la degradación de paraquat alcanzó 67, 83 y 88% en invierno, primavera y verano, respectivamente, sobre la cobertura plástica blanca. Sobre la cobertura negra, esos valores alcanzaron 66, 82 y 84%, respectivamente.

CP 20 - Anthracnose: A new disease on pitaya in South Florida. A. J. Palmateer and R.C. Ploetz. Department Plant Pathology, IFAS, Tropical Research and Education Center, University of Florida.

Columnar, climbing cacti in the genera Hylocereus and Selenicereus produce fruit known variously as pitaya, pitahaya, dragonfruit or strawberry pear. Hylocereus undatus, a native of Mexico that produces red fruit, has recently become a commercial crop in South Florida. In December 2004 a new disease was observed in a commercial planting in Miami-Dade County. Reddish-brown lesions with conspicuous chlorotic haloes developed on the ribs of vines, in particular where spines emerged from the rib edge. Eventually, lesions had white centers and coalesced to rot much of the vine column; in severe cases only the vascular column in the vine center remained unaffected. Salmon-colored spores and acervuli were observed in lesion centers. Disease samples were collected and tissues from lesion margins were surface disinfested and plated on one half-strength acidified potato dextrose agar. The fungus Colletotrichum gloeosporioides (Penz.) Penz. & Sacc was isolated from all symptomatic plant tissues. Fungal colonies produced abundant conidia in culture that were hyaline, straight, cylindrical, and averaged 14.7 µm (range 12.5 to 17.5 µm) by 5.0 µm (range 3.8 to 7.5 µm). Two isolates of C. gloeosporioides were shown in repeated experiments to cause the described disease. The age of vine segments had no significant effect on lesion development, and the study isolates were recovered from inoculated plants. Koch’s postulates were completed with the reisolation of the isolates that were used to inoculate plants. This disease had apparently not been reported previously on this crop.

CP 21 - Classical biological control of citrus pests in Florida and the Caribbean: Interconnections and sustainability. M. A. Hoy, University of Florida.

Beginning in 1993, Florida’s citrus industry was invaded by citrus leafminer (Phyllocnistis citrella), brown citrus aphid (Toxoptera citricida), and the Asian citrus psylla (Diaphorina citri). The sources of these pests are unknown, but other countries in the Caribbean have also suffered from invasions by these pests. Brown citrus aphid and Asian citrus psylla are vectors of citrus tristeza virus and greening disease, respectively, whereas citrus leafminer damage provides openings for invasion of the citrus canker pathogen. All three pests were candidates for classical biological control. Dr. Ru Nguyen (Division of Plant Industry, Gainesville, FL) has collaborated on importing, evaluating, rearing and releasing parasitoids between 1993 and the present. Ageniaspis citricola was imported from Australia, Thailand and Taiwan and became the dominant parasitoid in Florida. Ageniaspis citricola has been supplied to colleagues in several countries from our rearing program. Two parasitoids were imported for control of the Asian citrus psylla, Tamarixia radiata and Diaphorencyrtus aligarhensis and the parasitoid Lipolexis scutellaris, which was later designated L. oregmae, was imported with the assistance of a colleague in Guam for a classical biological control program directed against the brown citrus aphid. These parasitoids, our rearing methods and risk assessment data, were provided to other countries, all of which assisted the recipients by reducing the costs of importation and evaluation. Classical biological control historically has fostered cooperation, interconnections, and sharing of resources and knowledge; this networking must be maintained and enhanced if it is to be sustained as a viable pest management tactic against invasive pests in the Caribbean.

CP 22 - The need for a molecular signature for Brevipalpus exotic mites and mite-borne diseases approaching the Caribbean Basin. J.C. Rodrigues, R. Ochoa, C. Welborn, and C. C. Childers, University of Puerto Rico, Agricultural Experiment Station.

A complex of Brevipalpus species (Acari: Tenuipalpidae) is assumed to exist within citrus, coffee, and other perennial cultivated plants throughout South, Central, and North America and the Caribbean. More in-depth taxonomic and distribution studies of mite populations on citrus and non-citrus hosts are important steps towards the development of control efforts for Brevipalpus-vectored diseases such as citrus leprosis (CiLV) and Coffee ringspot virus (CoRSV). Knowledge of the genetic diversity of the species and their ability to transmit the different viruses is crucial to designing control tactics. So far, mitochondrial molecular analyses have shown diversity for Brevipalpus species from Florida and Sao Paulo citrus-growing areas. Citrus leprosis is a main citrus viral disease caused by two different viruses, called nuclear (CiLV-N) and cytoplasmic type (CiLV-C). Both viruses are persistently transmitted by B. phoenicis, and only CiLV-C has been characterized. CiLV has been reported in different countries in Central America (Panama, 2001, Honduras and Guatemala, 2003; and most recently, Mexico, 2005. CoRSV affects coffee plantations in Brazil and Costa Rica, and could affect the coffee growing areas of the Caribbean. In addition, Brevipalpus mite-vectored viruses are a potential problem for the tropical and subtropical ornamental plant industry. These different diseases are in Central America and could reach or already be present in the Caribbean Basin. Because of this threat, it is important to gather information about diversity and potential vector capacities of local uncharacterized complexes of Brevipalpus mites.

CP 23 - Phytophagous mites associated with mango seedlings in Puerto Rico, and a report for Neocalacarus mangiferae (Acari: Eriophyidae), a newly introduced mite. A. Segarra and N. Nieves. University of Puerto Rico, Agricultural Experiment Station.

There are several economically important mite species associated with mango in Puerto Rico. Published reports have associated some of these mites with the mango malformation syndrome (MMS). This papaer gives details on a two-year study of the relationship between MMS and mites commonly found in mango nurseries. Common phytophagous mites present in weekly surveys were the broad mite (Polygophagotarsonemus latus), the mango bud mite (Aceria (=Eriophyes) mangiferae), and Neocalacarus mangiferae. The latter is a new record for the Caribbean. This mite was described from India in 1966, and reported in Brazil (2000) and Australia (2003). Little is known on the bionomics of this mite. Twenty-six weeks of observation revealed no association of N. mangiferae with any visible damage to seedlings, as compared with seedlings in a sprayed control group. This finding may confirm its reported status as a leaf vagrant. Experimental infestations with broad mites (P. latus) showed extensive damage to new leaves, and were an important source of leaf deformation and defoliation, as compared to damage in control seedlings. Mango bud mites (E. mangiferae) caused bud necrosis and loss of seedling apical dominance. Other less common mites found during the surveys were Tetranychus sp. and Tegonotus mangiferae (Acarina: Eriophyidae), neither of which was associated with MMS symptoms.

CP 24- Managing the sweet potato grub in St Vincent and the Grenadines. P. Titus and K. Dalip. Caribbean Agricultural Research and Development Institute (CARDI).

Sweet potato (Ipomoea batatas L.) is a major export crop for St Vincent and the Grenadines, with 2,654 metric tonnes (valued at US $893,363) exported between 2001 and 2003. However, the production of sweet potato is affected by the sweet potato grub (Phyllophaga spp), which is the major pest of economic importance affecting the crop in St Vincent and the Grenadies. Damage to tubers caused by this pest is estimated to be as high as seventy percent in some cases. Experiments were conducted at the CARDI Field Station using three sweet potato varieties (Black Vince, Big Red and Lover's Name) grown in St Vincent and the Grenadines to test the efficacy of three chemical - Neem X (active ingredient azdirachtin), Actara (active ingredient thiamethoxam) and Pirate (active ingredient chlorptrifos) in suppressing the pest population and resultant tuber damage. A complete randomized block design was used in the trials in which the insecticides were applied to the soil before and at early planting. The manufacturers' recommended rates were used and treatments were replicated three times. Results obtained over two planting seasons showed that plots treated with Actara produced tubers with less damage than the Neem X and Pirate treated plots. These results are very promising as the use of these chemicals can be included as one component in an integrated management programme for the sweet potato grub.

CP 25 - Evaluation of pheromone traps performance for the detection of the banana root borer, Cosmopolites sordidus (Germar), on plantain crops. R. A. Franqui¹, J. A. Chavarría¹, and C. Flores². ¹Department of Crop Protection, ²Department of Horticulture, University of Puerto Rico, Agricultural Experiment Station.

Adult populations of the banana root borer, Cosmopolites sordidus, were surveyed in plantains during a 10-month period using two trap systems: (1) pseudostem traps (control), and (2) a commercial trap + Cosmolure®. In addition, the relationship between adults captured and larval densities in plantain corms was examined. The most effective trap system was the commercial trap + Cosmolure®; the sex ratio was not significantly different from 1:1.

CP 26 - Efecto de competencia de las malezas en el rendimiento del cultivo de yuca (Manihot esculenta Crantz) en Esperanza, República Dominicana. R. Hernández. Instituto Dominicano de Investigaciones Agropecuarias y Forestales (IDIAF).

El control de malezas durante las primeras etapas de desarrollo en el cultivo de la yuca es uno de los factores más importantes a considerar para obtener rendimientos altos. Sin control, los rendimientos del cultivo pueden disminuir en más del 50%, puesto que las plantas jóvenes son susceptibles a la competencia con las malezas por luz, nutrientes y agua. En República Dominicana los productores en zonas bajo riego difieren en el número de desyerbos y el momento en que deben realizarse. Muchos hacen sólo dos desyerbos, mientras otros realizan cuatro o más, atendiendo a razones económicas más que al efecto sobre los rendimientos. Esta investigación tuvo por objetivo determinar el efecto del período crítico de competencia de las malezas en los rendimientos de raíces frescas comerciales, en la variedad de yuca ‘Americanita’. Se realizó en Esperanza, provincia Valverde, República Dominicana en el período octubre 2001-agosto 2002. Se utilizó un diseño de bloques completos al azar con seis tratamientos y cuatro repeticiones. Los tratamientos fueron: siempre limpio, 35, 49, 63 y 77 días con malezas seguido de desyerbos cada 28 días, hasta 161 días después de la siembra. Un análisis de regresión lineal mostró que a medida que el período con maleza aumenta en 14 días, los rendimientos disminuyen en 0.25 t/ha (p=0.03). Según el análisis de presupuesto parcial, la inversión en 3.5 desyerbos manuales a partir de los 35 días de la siembra y cada 28 días permite recuperar cada RD$1.00 invertido y obtener RD$1.60 adicional.

CP 27 - Non-indigenous insect species in Puerto Rico: A case study. R. A. Franqui. Department of Crop Protection, University of Puerto Rico, Agricultural Experiment Station.

Invasive species are a major threat to natural ecosystems and their species, second only to direct destruction of habitats by humans. The impact of invasive species is particularly devastating to island ecosystems, which harbor much of the world's threatened biodiversity. Among these isolated populations, extinction rates are especially high. This problem is growing in severity and geographic extent as volume of international trade and travel increases. Because of its environmental conditions and since it is one of the centers of commerce and greater mobilization of cargo of the Caribbean, Puerto Rico is constantly threatened by the introduction of exotic insects. These species are generally major pests of considerable economic risk for the agricultural industry on the Island. There is evidence that during the last 40 years an average of 1.37 invasive insect species per year have been introduced into the island. Most introductions were recorded during the 1980s and 1990s. This increase is mostly due to the physical impossibility of inspecting all people and cargo, low probability of discovering agricultural contraband, increased volume of passenger traffic, containerized shipping practice, lack of trained taxonomists and other diagnostic and control personnel, and first class mail route of entry of non-native species. In addition, the introduction of these exotic pests compromises our efforts in facilitating exports with our trading partners, who are equally concerned about these damaging pests.

CP 28 - Caracterización de tres suelos tropicales y su influencia en la adsorción de metolaclor y carbofuran. J. A. Dumas, P. Nkedi y R. Montalvo. Universidad de Puerto Rico, Estación Experimental Agrícola.

La adsorción de los compuestos orgánicos en el suelo principalmente ocurre a través de las interacciones con la materia orgánica presente en los mismos. El contenido de materia orgánica es el principal determinante relacionado con la movilidad de un plaguicida a través del suelo. La materia orgánica en los suelos está compuesta por ácidos húmicos (AH), ácidos fúlvicos (AF), grasas, aceites y otros. Cada fracción tiene un peso en la adsorción de los compuestos exógenos al suelo. Se caracterizó la materia orgánica presente en suelos tropicales de las series Tiburones, Aguilita y Cataño, los cuales presentan un comportamiento marcadamente distinto en la constante de adsorción (Koc) de metolaclor y carbofuran. Los valores encontrados en las muestras de suelos, hasta una profundidad de 60 cm, variaron desde 34 a 1,181 ml/g para carbofuran y desde 90 a 298 ml/g para metolaclor. La caracterización de los suelos, en términos de pH, conductividad, tamaño de partículas y contenido de carbonato de calcio, mostró marcadas diferencias entre los mismos; estas diferencias pueden ser responsables de las diferencias en la composición química de la materia orgánica altamente meteorizada. El contenido aromático y alifático de los AH y los AF se midió usando espectroscopía de ultravioleta-visible. Los índices de absorción E4/E6 para una solución de 100 ug/ml de los AH de los suelos Aguilita, Cataño y Tiburones, disueltos en una solución de 0.05N NaHCO3, de pH 8.1, fueron de 5.5, 4.9 y 3.2, respectivamente; para los AF, en una solución 2N HCl, los índices fueron 10.0, 6.5 y 10.4 para estas mismas series de suelos, respectivamente. Estos valores sugieren un carácter altamente aromático para los AH (E4/E6 ~3) extraídos de la serie de suelo Tiburones, mientras que la serie de suelo Aguilita mostró el mayor carácter alifático. En el caso de los AF, los suelos Aguilita y Tiburones mostraron un mayor carácter alifático (E4/E6 > 8), mientras que el suelo Cataño mostró un carácter intermedio. Los datos sugieren que las diferencias encontradas en las constantes de adsorción para los dos plaguicidas son debidas en parte a las diferencias en la composición de los AH y AF de los suelos.

Palabras Clave: Coeficiente de adsorción, Ácido húmico, Ácido fúlvico, Metolaclor, Carbofuran

Forages (FOR)

FOR 1 - Potential leguminous shrubs for meat goat production in Florida. M. B. Adjei¹ and E. Valencia². ¹University of Florida, Range Cattle REC Experiment Station, Ona, FL and ²University of Puerto Rico, Agricultural Experiment Station.

Nursed seedlings of 15 selected accessions of browse leguminous species were established during 2003 in 6-m rows at the Range Cattle REC, Ona, FL on a Pomona fine sand (sandy, siliceous, hyperthermic Ultic Alaquod). There were four rows for each entry in a randomized complete block design. Average plant population in the row increased for Leucaena accessions to 108-193% of initial, was maintained at ~100% of initial for Desmanthus accessions, but declined slightly for Desmoduim accessions to 91% of initial level over a 2-yr period. Edible forage of all legumes had good nutritive value (>120 g kg^-1 of crude protein and >550 g kg^-1 of in vitro organic matter digestion); however, Desmanthus accessions had much lower nutritive values than the other genera. On the basis of initial survival and vigor ratings, two accessions of each of the genera indicated were evaluated for preference of palatability by goats in four trials during 2005. The probability of being selectively grazed by goats, when freshly-harvested legumes were offered in a cafeteria-style on a bahiagrass pasture, averaged 26% of grazing time for Desmodium accessions, 2.5% for Leucauna accessions and 1.0% for Desmanthus accessions. Consequently, the two experimental Desmodium heterocarpon accessions and the released Desmodium heterocarpon cultivar (Florida carpon desmodium) were established into bahiagrass pasture for on-going comparative grazing evaluation to measure performance of pasture types and meat goat production.

FOR 2 - Effect of cattle manure application rate and strategy on bahiagrass yield and nutritive value. K. Obour¹, M. B. Adjei¹, E. Valencia² and J. E. Rechcigl³. ¹University of Florida, Range Cattle REC, Ona, FL, ²University of Puerto Rico – Agricultural Experiment Station, and ³University of Florida, Gulf Coast REC, FL.

We evaluated the effects of N rate and two application strategies of cattle manure (CM) on dry matter yield (DMY) and nutritive value of bahiagrass (Paspalum notatum L. Fluege). The N rate treatments were 200 and 400 kg N ha^-1 from CM or 50/50 CM plus ammonium nitrate (AN) combination, applied either in a single or split dosage. Bahiagrass was clipped at 28-d intervals for DMY, crude protein concentration (CP) and in vitro organic matter digestibility (IVOMD). First year results showed significant effects of application strategies and N rate. The combination of CM +AN performed better than treatments with CM alone. Dry matter yields of 6.67, 6.46, and 6.27 Mg ha^-1 were recorded for the 400 kg N ha^-1 as CM+AN in single and split, and for the 200 kg N ha^-1 as CM+AN in split applications, respectively. Comparatively, DMY of 6.38, 5.35, 5.98 and 4.82 Mg ha^-1 were recorded for the 400 kg N ha^-1 of CM in single and split, and for the 200 kg N ha^-1 of CM in single and split applications, respectively. The 400 kg N ha^-1 of CM+AN had the greatest IVOMD values of 547 and 543 g kg^-1 for the single and split applications. Treatments receiving split application of CM had the lowest DMY, IVOMD and CP values. Phosphorus uptake and percentage recovery were also greatest for treatments that received CM+AN combination. Between 23 to 26% of the applied P was recovered in the CM+AN treatments compared to 10-21% in the treatments that had CM alone. The results show that applying CM in combination with an inorganic nitrogen source can provide high forage yield of high quality and also reduce P risk to the environment.

FOR 3 - Persistence and yield of Brachiaria cultivars on an Ultisol in Puerto Rico. R. Ramos¹, E. Valencia¹, A. A. Rodríguez², and H. Díaz². ¹Department of Agronomy and Soils and ²Department of Animal Industry, University of Puerto Rico – Mayagüez Campus.

Grass cultivars Mulato (a hybrid; Brachiaria brizantha x B. ruziziensis), Marandu (B. brizantha) and Toledo (B. brizantha) are the most important tropical grass releases in Latin America for grazing. However, information on yield and persistence of these cultivars in Puerto Rico is unknown. This study assessed yield, nutritive value and mobgrazing effects of cvs. Mulato, Marandu and Toledo. The study was conducted at the Corozal substation of the Agricultural Experiment Station, University of Puerto Rico. Soil type was of the Corozal series (fine clay, mixed, isohypetermic Aquic Haplohumults). Established stands (four replicates of 0.005 ha each) of Mulato, Marandú and Toledo were stocked every 35 d during the short day season and every 28 days during the long day season using yearling steers (mob-grazed for 1 to 2-d to a 15-cm height). Prior to grazing, a 1 m² quadrat was clipped, weighed and dried to determine dry matter yield; subsamples (500 g; four samples in the year) were ground to determine chemical composition [crude protein (CP), neutral detergent fiber (NDF), and acid detergent fiber (ADF)]. All pastures were mob-grazed for 15 grazing cycles to determine changes in yield over time. Mean yield of Mulato (1207 kg ha^-1), Marandu (1094 kg ha^-1) and Toledo (1271 kg ha^-1) were different (P<0.05), but there were no differences in CP (6.8%). There was a cultivar effect (P<0.05) on NDF and ADF, with a lower NDF (64.6%) and ADF (33.6) for Mulato. There was a grazing cycle date effect on yield (P<0.05) consistent with rainfall patterns and day length. After 1.5 years of grazing it is evident that all three cultivars persisted, but that grazing management is needed (longer periods of regrowth) during the dry periods.

FOR 4 - Evaluation of dry matter yield and nutritional composition of Digitaria decumbens cv. Transvala hay with three mowing frequencies and fertilizer levels. J. M. Isma, N. Daniel, A. Santana, C. M. De Jesús, and R. A. Vásquez. Instituto Superior de Agricultura de la República Dominicana.

Hay production is coming to be a normal activity for the Dominican livestock farmer and it has been stimulated lately by the agricultural extension program MEGALECHE as an alternative to provide roughage for the livestock in the dry season as surplus forages. Taking account of this situation, and to answer Dominican farmers’ questions about the fertilizer rate and mowing frequency to make high quality hay from Transvala grass, a study was designed in the CIMPA in a two-year-old field of Transvala to evaluate for six months the effects of the three levels of fertilizer and three frequencies of mowing with superficial irrigation. The fertilizer levels were 0, 150 and 300 kg/ha per year of nitrogen and the mowing frequencies were 28, 35 and 42 days. The study had a split plot design with three blocks and nine plots with an area of 0.031 ha each. All plots were irrigated ten days after being mown and the granular fertilizers were distributed by hand at fifteen days after mowing. The variables evaluated were DM, CP, ADF, NDF and the cost-income rate. No significance was observed among the variables (P>0.05). However, the larger content of CP was found at 35-day mowing and 300 kg/ha/year of nitrogen with 11.49% and 34,339 kg/ha/year of DM, respectively. Also, the combination of 35-day mowing and 300 kg/ha/year of nitrogen had the higher income rate. Therefore, we concluded that the frequency of 35-day mowing and 300 kg/ha/year of nitrogen should be used to produce a high quality grass hay of Transvala.

FOR 5 - Efecto de niveles de altura de corte en la relación hoja - tallo y materia seca total de morera (Morus alba). E. J. Almánzar, B. Wagner y J. Melidiana. Universidad Autónoma de Santo Domingo (UASD), República Dominicana.

Por su alto valor nutritivo, el follaje de morera es utilizado por productores pecuarios como alternativa forrajera para abaratar los costos de alimentación del ganado. El objetivo de este estudio fue determinar el efecto de la altura y nivel óptimo de corte en la relación hoja/tallo y el rendimiento de materia seca total de la morera en secano. El estudio se realizó durante un año a partir del corte de homogenización, en la Estación Experimental Engombe, Universidad Autónoma de Santo Domingo, situada a 20 msnm, con precipitación y temperatura media anual de 1,575 mm y 25 °C, respectivamente, y humedad relativa de 78%, suelo franco arcilloso con 2.8% MO y pH 6.8%. Se utilizó un diseño completamente al azar con cuatro tratamientos, representados por la altura de corte: T1 = 0.20 m, T2 = 0.50 m, T3 = 1.0 m y T4 = 1.50 m, con cuatro repeticiones. Las variables estudiadas fueron relación hoja/tallo, rendimiento de materia seca de hojas y tallos y de materia seca total (en kg/ha). Los datos se analizaron bajo el programa SAS. La plantación tenía un año de establecida, con marco de plantación de 0.20 m entre plantas y un metro entre líneas. Las evaluaciones se realizaron cada 60 días en un metro cuadrado (área útil). Se midió la altura y se contaron las ramas según el tratamiento; se pesaron las hojas y tallos para determinar la relación hoja/tallo y rendimiento total; y se determinó el contenido de proteína cruda, fibra, fósforo, calcio, ceniza y materia seca. Los resultados indican que no hubo diferencias estadísticas significativas (Duncan P>0.05) entre tratamientos en la relación hoja/tallo, ni en materia seca total.

FOR 6 - Efecto de los bloques multinutricionales vs. una premezcla mineral comercial en novillas añojas. J. Caridad. Instituto Dominicano de Investigaciones Agropecuarias y Forestales (IDIAF).

Debido a la gran variedad de suplementos minerales que existen en el mercado, el costo y la calidad de los mismos, se realizó un ensayo en el Seibo donde se estudiaron dos tipos de suplementación, una mineral y otra mineral, vitamínica, energética y proteica. Se utilizaron 70 novillas mestizas de Simmental x Cebú con peso promedio de 203 kg. El ensayo se inició en diciembre de 2002. Las variables fueron ganancia diaria, consumo, porcentaje de novillas que presentaron celo durante el ensayo y factibilidad económica. El pasto fue Bermuda costera (Cynodon dactylon) con una carga animal de 2.28 UB/ha. Para analizar las variables se utilizó la prueba “t” de Student. Los tratamientos consistieron en T1 = fosfato monodicálcico + sal, y T2 = bloques multinutricionales. El consumo promedio del T1 fue 0.525 kg y el del T2 fue 0.498 kg; la ganancia diaria fue de 0.497 y 0.466 kg/día; el costo/qq fue de RD$610.00 y RD$600.00 y el porcentaje de novillas servidas al primer celo fue de 17% y 37% para fosfato monodicálcico (T1) y bloques multinutricionales (T2), respectivamente. El análisis estadístico arrojó que no hubo diferencias significativas entre los tratamientos con respecto a ganancia diaria, costo y consumo, mientras que el porcentaje de servicio al primer celo fue significativo a favor del grupo que consumió bloques multinutricionales, con una diferencia de 20% más de novillas servidas que el grupo que consumió la premezcla mineral (fosfato monodicálcico + sal).

Palabras Clave: Bloques multinutricionales, Suplemento mineral, Novillas mestizas

FOR 7 - Dairy waste effluent effects on forage yield of tropical grasses and soil P. E. Valencia¹, R. Ramos¹, R. Tirado¹, and H. Díaz². ¹Agronomy and Soils Department, ²Department of Animal Industry, University of Puerto Rico, Mayagüez Campus.

In Puerto Rico, dairy producers spray dairy waste effluent (DWE) on grass fields to comply with regulations governing the on-farm recycling of nutrients. The DWE provides nutrients and water for grass growth, and its judicial use can minimize mineral contamination of groundwater. A field study was conducted to assess four effluent N rates of 0, 100, 200, and 300 kg ha^-1 effects on dry matter yield (DM) of guineagrass (Panicum maximum Jacq cv. Mombasa), Bracharia brizantha cv. Mulato and Stargrass (Cynodon plectostachyus). Soil at the Lajas Substation was of the Fraternidad series (fine, smectic, isohyperthermic Typic Haplusterts). The experimental design consisted of four replicates in a split-plot arrangement (grasses as the main plots and levels of DWE as subplots). Dairy waste effluent was applied to achieve an annual target of N in August 2005. A 1-m² quadrat was harvested every 28 d (for 196 d) to measure DM (kg ha^-1) and soil samples taken at two depths, 3 mo after DWE applications for P analysis. There were significant differences (P<0.05) in DM for tropical grasses (1,272; 1,142; 944 kg ha^-1, for Mombasa, Mulato, and stargrass, respectively). There was no effect (P>0.05) of DWE rates on DM for any of the grasses. There was, however, a day and DWE-by-day interaction (P<0.001) for Mombasa and stargrass, but not for Mulato. Harvested DM decreased from 2,136 kg ha^-1 in d 28 to 627 kg ha^-1 for d 196 for Mombasa, and from 1,790 to 639 kg ha^-1 for stargrass. Neither soil pH nor P was significantly affected by DWE rates, except that P was higher in the first 15-cm (2.6 mg kg-1) of top soil than in the 30-cm (2.05 mg kg^-1). This study suggests that higher rates of DWE can be applied to these grasses, and preferably in split applications to have a more efficient nutrient utilization.

Food Safety and Value Added Products (FS-VA)

FS-VA 1- Research on Salmonella incidence in parent breeding flocks for layer eggs in Suriname. M. Ramdin. University of Suriname.

The local layer industry revolves around two commercial breeder farms with their own hatcheries, fifteen commercial and sixty small table egg farms, five input supply shops and three feed mills. Generally, the scale of operation in Suriname is small. Earlier studies have shown that one of seven table eggs is infected with Salmonella. The average number of detected Salmonella infections locally is sixty five per annum. Since the local production of hatching eggs exceeds the demand, part of the eggs are also used for this study. Acknowledging these facts, this study is conducted to: (1) investigate the rate and (sub) species of Salmonella bacteria in local breeding flocks for layers, and (2) evaluate the production of the visited egg farms. All breeding flocks and random samples of hatchery residues will be sampled in duplicate and analyzed at the Laboratories of the Center of Agricultural Research in Suriname (Celos). Statistics will be used in the analysis of data. Results will provide information so that further study can determine whether transmission of the bacteria is horizontal and/or vertical. After completion of the study, farmers will receive recommendations on preventive actions for Salmonella incidence.

FS-VA 2 - Food safety concerns and fertilizer-use potential of food processing biosolids for vegetable and forage production. M. St. Luce, G. Gouveia, and G. Eudoxie. University of West Indies.

Increasing growth in the manufacturing sector in the Caribbean, particularly in Trinidad and Tobago, is contributing to increased waste generation and thus creating a waste management problem. Limited land availability for suitable landfills, compounded by concerns of environmental pollution, has created a need for alternative avenues for waste utilization. A 3x3 Latin Square experiment is being conducted on a mixed loamy isohyperthermic Fluventic Eutropepts with Pak-Choi (Brassica rapa var. chinensis) and Tanner Grass (Brachiaria arrecta) as the test crops, to evaluate the effectiveness of food processing biosolids as an ameliorate in crop production and food quality. The biosolid, applied on the basis of nitrogen rate, is compared in performance with urea and triple super phosphate. Particular emphasis is being placed on the levels of heavy metals that the crops assimilate since this is a very important food safety issue. The availability and increase in heavy metals in the soil as a result of biosolid application will also be discussed.

FS-VA 3 - Improving food safety management practices: A consumer-oriented approach. M. Gosein. Caribbean Industrial Research Institute (CARDI).

The traditional approach to food safety management in the Caribbean has been the establishment of legislation to regulate the operations of the industry. Whereas this has had some impact on improving the level of food safety, it has proven to be inadequate in achieving the desired results. In many of the English-speaking Caribbean countries, the legislation has not been updated for decades and in some cases legislation from the mid 20th century still governs the operations of food enterprises. Countries have for a myriad of reasons failed to continuously update their regulations in what is a dynamic industry. Even where appropriate legislation exists, many countries have not allocated the necessary resources to monitor and enforce the legislation. There is also a lack of physical infrastructure, primarily accredited testing laboratories, to support this approach to food safety management. Although legislation is absolutely important for the control and improvement of food safety management practices, it is not the only available mechanism. Many countries have failed to use the power of consumers to improve food safety management practices. This market-led approach can significantly reduce the demands on government resources. It requires that consumers be aware of critical food safety issues and make their purchasing and consumption decisions with this knowledge. This requires appropriate public awareness and education programs throughout society. If consumers require higher levels of food safety management, then this demand can be much more effective in forcing a change. It can also be more cost efficient. A study of food safety perceptions among consumers in Trinidad in the late 2005 revealed that most consumers are not satisfied with food safety practices at food outlets. Their greatest concerns lie with road-side vending, a typical practice in the Caribbean. There is a strong feeling that the authorities are not doing enough to educate the public on food safety issues and that appropriate regulations are not in place. In spite of these concerns, and recognition of poor quality practices, many consumers continue to purchase food from these vendors. Although these results are specific to road-side food vending, there is every reason to believe that these feelings also apply to the food processing industries. Through education and awareness, consumers can force both manufacturers and food vendors to improve their practices.

FS-VA 4 - Food safety problems found in SMEs in the agro-processing and food service sectors in the Caribbean and strategies in finding solutions. M. Taylor, S. Mohammed, S. Peart. Caribbean Food Safety Centre (CFSC).

Contaminated food kills millions of people around the world each year. Here in the Caribbean the exact number of persons who die each year from foodborne illnesses is unknown. SMEs in agro processing and food service make up a large percentage of the players in the food sector of the region, and their practices are at times called into question. For these establishments, the critical food safety problems that mar the production of safe food include poor personal hygiene, inadequate cleaning and sanitizing practices, inefficient pest control, improper use of preservatives, unsatisfactory time/temperature relationships, inadequate training and inadequate infrastructure. Possible strategies to assist in solving these problems would involve updating and strengthening of current legislation, improved surveillance and monitoring, training of staff of the SMEs issues relating to food safety management and production methods, and outreach programmes on food safety that target the general public and school children. Integral to all of this is the sharing of ideas and information and the pooling of data from all of the countries of the region in an effort to accelerate the thrust toward the production of safe food.

FS-VA 5 - Food safety in farmer participatory learning: The Trinidad and Tobago experience. D. V. Ramroop. Ministry of Agriculture, Land and Marine Resources - Trinidad and Tobago.

Over the past few decades farmers in Trinidad, and indeed the Caribbean as a whole, depend on excessive pesticides and other inputs in the production of short-term and high-value crops. This has had serious negative implications on the environment, farmer and farm worker health and consumer health. Against this background it became imperative to find alternatives and to rationalize the use of chemical pesticides. A pilot Farmer Field School (FFS) project introduced the use of Farmer Participatory (FP) approaches for Ecological Crop Management (ECM) in Trinidad and Tobago during 2002/03. The pilot FFS was conducted in the Caura Valley, an area of intensive vegetable production. The FFS provided the participants (both farmers and extension/research officers) with the skills, knowledge and confidence to make ecologically sound and cost effective decisions on crop health and safety. Fourteen FFS were conducted throughout the island during the period 2003 – 2005 and preliminary Impact Assessment Studies have indicated that farmers have now adopted several IPM options including resistant varieties, biological control, cultural control systems and minimal pesticide use. This paper outlines and underscores the need for farmer field schools and related farmer participatory approaches as a means to a more rational overall strategy of pest control, reduction in pesticide use and costs of chemical inputs, meeting of international market requirements, and healthier food for consumers.

Keywords: Ecological crop management, Farmer participatory approaches, Farmer field schools, Food safety

FS-VA 6 - The role of probiotics as functional food components. M. Velázquez. University of Puerto Rico, Mayagüez Campus, Food Science and Technology Program.

Functional food components also known as nutraceuticals are those ingredients that provide a health benefit or desirable physiological effect beyond basic nutrition. These functional components include dietary fiber such as beta glucan, fatty acids such as omega-3 fatty acids, flavonoids, plant sterols, phytoestrogens, probiotics and prebiotics. According to recent marketing analyses, the functional food industry in the United States could double with estimated sales over $37.7 billion by 2007. This trend can be attributed to the growing consumers’ interest in maintaining their health, their aim for the improvement of their children’s nutrition, and their increased awareness regarding the connection between health and diet. An impressive list of functional foods has been recently launched onto the market. In 2005 alone, sixty-nine value-added new products were introduced, targeted specifically to the children’s market, containing healthy omega-3 fatty acids. There is a need to conduct research in the area of functional foods. Therefore, our research group is focused on developing functional foods specifically containing probiotics. Probiotics including bacteria from the genus Bifidobacterium are lactic acid viable and metabolically active microorganisms which, when administered in adequate amount, confer a health benefit on the host, including improvement of gastrointestinal health and the immune system. In particular, we are interested in developing an acid whey beverage fermented with lactic acid bacteria and yeast cultures containing probiotics as adjunct cultures added post-fermentation. Current research includes the isolation of lactic acid bacteria from commercial sources such as yogurt and probiotic capsules and the characterization of the isolates as Bifidobacterium for the incorporation into the acid whey fermented beverage as an adjunct culture.

FS-VA 7 - Auditing food safety systems for produce, R. E. Costa, President Environ Health Associates, Inc.

Food safety systems in agriculture are relatively new in response to buyer demands. Many producers, packers and processors of ready-to-eat produce are developing food safety systems. Many buyers of produce contract a third party auditing firm to validate and verify food safety systems in agriculture. Auditing firms often develop their own standards in conjunction with those of buyers. Therefore, producers must be familiar with the expectations of auditors when developing food safety systems. This paper discusses the typical audit criteria from farm to packing house to processor. The paper identifies the typical expectations of auditors for good agricultural practices, standard sanitation operating procedures and HACCP.

Horticulture (HORT)

HORT 1 - El bronceado de la habichuela (Phaseolus vulgaris L.) y su control en el Valle de San Juan. V. Morillo y J. Cepeda. Instituto Dominicano de Investigaciones Agropecuarias y Forestales (IDIAF).

Durante los años 2000 y 2001, en el Valle de San Juan se presentaron, en focos localizados, manchas irregulares de color bronce en las hojas de la habichuela, que redujeron los rendimientos del cultivo desde un 15 hasta un 80% en las zonas donde aparecieron. La presencia de este daño fue en aumento, particularmente en la variedad 'JB-178'. Observaciones iniciales no asocian la condición al ataque de plagas ni a enfermedades. Denominada en el 2001 como “bronceado de la habichuela” se presenta entre los 20 y 40 días después de la siembra. En el ciclo 2001-2002 se realizaron varios muestreos de suelo y foliares que permitieron asociar estos síntomas con deficiencia de zinc y magnesio. En el 2002, mediante pruebas preliminares en casa malla, el bronceado se controló en un 100% con sulfato de zinc a razón de 0.5 kg/ha. En el período 2002-2003 se estableció un experimento de campo con el objetivo de identificar los nutrientes responsables del bronceado. Se usó un diseño de bloques completos al azar con 11 tratamientos y cuatro repeticiones. Los tratamientos fueron los fertilizantes foliares más usados por los productores, los elementos zinc y magnesio y un testigo. Las variables medidas fueron número de plantas afectadas, número de legumbres por planta, número de semillas por legumbre, peso de 100 semillas y rendimiento. El número de plantas afectadas por bronceado se determinó mediante el conteo de plantas, comprobándose que el zinc lo corrigió con mayor efectividad. Para las demás variables, el análisis de varianza de los datos y la separación de medias con DMS 5% se realizaron con el paquete estadístico MSTAT-C. Sólo se encontró diferencia estadística significativa para la variable rendimiento, siendo el tratamiento T9 (sulfato de zinc) con 1,610.75 kg/ha el de mayor rendimiento y el T1 (Manvert Complex) con 976.38 kg/ha, el de menor. Para las demás variables no hubo diferencias estadísticas significativas.

HORT 2 - Development and marketing of selected fresh-cut tropical crops in Trinidad. G. Henry, A. Mootoo, R. Mamchan, and L. Harrynanan. Ministry of Agriculture, Land and Marine Resources - Trinidad and Tobago.

Trinidad has been producing fresh-cut fruit and vegetable products since the mid 1990s and the quantity and range of products have been expanding. The staff of the Postharvest Unit of the Research Division of the Ministry of Agriculture, Land and Marine Resources conducted a survey of the retailing of the fresh-cut products in Trinidad. The results were reported to stakeholders at a seminar/workshop in January 2006. The quantity and quality of domestically produced raw materials, papaya (Carica papaya L), watermelon (Citrullus lanatus), pineapple (Ananas comosus (L.) Merr), dasheen leaves (Colocasia esculenta), pumpkin (Cucurbita maxima), okra (Hibiscus esculentus L) used in fresh-cut products were not consistent; this finding has implications for the sustainability and profitability of the fledging industry. Both survey and workshop discussions revealed that although the products had strong visual appeal, stringent consistent quality standards were lacking. Future prospects were examined and recommendations made for improvements in that sector. Recommendations were also made for developments in the quality, safety and marketing of fresh-cut products. International food safety standards need to be applied to ensure a consistently safe product for the consumer. Key areas for research, development and education were identified at the workshops’ discussions and these were presented as short- medium- and long-term strategies for the development of a vibrant fresh-cut industry in Trinidad.

Keywords: Fresh-cut tropical produce, Quality, Food safety standards, Management

HORT 3 - Efecto del descole y el desdede sobre el tamaño de la fruta del banano (Musa AAA) clon Gran Enano. H. Ricardo, E. De Jesús, R. Castro y R. Ortiz, Instituto Dominicano de Investigaciones Agropecuarias y Forestales (IDIAF).

Para mejorar el tamaño de la fruta y conseguir la calidad exigida en los mercados de exportación, los productores de banano convencional realizan las prácticas del desdede y el descole en el racimo. Durante el período abril-agosto de 2005 se desarrolló una investigación en la Estación Experimental Azua del Instituto Dominicano de Investigaciones Agropecuarias y Forestales (IDIAF) para determinar el efecto de estas prácticas en banano cultivado bajo condición orgánica. En un diseño completamente al azar se condujo un experimento factorial de dos factores: el desdede (eliminación de cero, dos y cuatro frutos de los laterales de cada mano de frutos verdaderos), y el descole (eliminación de raquis a partir de tres, cinco y siete nudos después de la mano falsa de frutos). La combinación de los niveles produjo nueve tratamientos, los cuales se repitieron cuatro veces. Las variables medidas fueron longitud y grado de los frutos centrales externos de la primera y última mano del racimo. Los datos se procesaron mediante análisis de varianza y regresión. La cantidad de manos por racimo se utilizó como covariable. Ni el efecto del descole ni su interacción con el desdede fue significativa en las longitudes ni en el grado de los frutos de la primera y última mano. Se encontró relación entre el desdede y las longitudes y grados de los frutos de la primera y última mano. La variación registrada en la longitud de fruto de la primera mano fue más influenciada por la cantidad de manos en el racimo (P=0.002), que por el desdede (P=0.01); a su vez, el efecto del desdede sobre la longitud de los frutos fue más significativo en la última mano (P=0.006) que en la primera (P=0.01). En los tratamientos sin desdede la longitud y el grado del fruto de la primera mano (23 cm; 40.5 mm) y de la última mano (19.9 cm; 39 mm) cumplieron con los estándares requeridos por los mercados de exportación, lo cual revela el efecto reducido de estas prácticas sobre el tamaño de la fruta del banano cultivada bajo condición orgánica en Azua, pudiendo ser innecesario el uso de estas prácticas.

HORT 4 - Influencia de métodos de desmucilaginado y reposo sobre la calidad del café (Coffea arabica) en Chene, Barahona, República Dominicana. M. Cuevas, H. Jiménez, J. Candelario y B. Toral. Instituto Dominicano de Investigaciones Agropecuarias y Forestales (IDIAF).

Los cambios producidos en los hábitos de consumo del café han provocado la creación de nichos de mercados a nivel mundial que prefieren cafés especiales. A pesar de que el país cuenta con condiciones edafoclimáticas para producir café de calidad, la calidad puede perderse o disminuir en el proceso del beneficiado, sobre todo al desmucilaginar. Esos nichos entienden que el método mecánico para remover el mucílago no produce café de calidad, que sólo se logra al hacerlo por fermentación natural. La fermentación natural conlleva un alto consumo de agua y vertido de aguas mieles que contaminan el ambiente. Un estudio se realizó en la finca de un productor en Chene, Provincia de Barahona, para determinar la influencia de los métodos de desmucilaginado y reposo en la calidad organoléptica del café. Se utilizó un diseño completamente al azar con cinco tratamientos y cuatro repeticiones. Los tratamientos fueron desmucilaginado mecánico y fermentación natural, con y sin reposo en agua por 12 horas y fermentación anaeróbica. Se recolectó café 100% maduro. De acuerdo a los resultados, desde el punto de vista organoléptico, el café de los tratamientos resultó de buena calidad, con acidez agradable y ligeramente más ácidos que amargos. No hubo diferencias significativas sobre la preferencia, el porcentaje de defectos ni en el rendimiento de café uva a oro limpio. En los análisis químicos hubo diferencias significativas (Pr > F = 0.0283) en el contenido de azúcar. En densitometría, el 97% de los granos estuvo sobre la malla 16. De acuerdo a estos resultados, para obtener café de calidad se puede utilizar cualquiera de los métodos de desmucilaginado, si éstos se realizan adecuadamente.

HORT 5 - Effects of drought on stomatal resistance, surface resistance and leaf temperature in four genotypes of common bean (Phaseolus vulgaris L) under greenhouse environment. V. H. Ramírez, B. Timothy, G. Porch, and E. W. Harmsen, University of Puerto Rico – Mayagüez Campus.

Stomatal resistance (rl), surface resistance (rs) and leaf temperature (TL) are important physiological variables for understanding the interaction among the soil, plant, and atmosphere. These variables are used to study the response of plants to abiotic stress conditions, such as drought and high temperature, in addition to micrometeorological variables such as evapotranspiration (ET). The goal of this research was to measure the rl, rs and TL of four genotypes of common bean (Phaseolus vulgaris L) under drought and non-drought conditions in a greenhouse environment. Three drought-tolerant genotypes were studied, BAT-477, SER-16 and SER-21, and one drought susceptible genotype, Morales. Three water regimes were used: full water supply (FWS) using 80% of the daily available water (DAW) during the complete growing season; Stress 1 (S1) with 50% of the DAW before flowering and 60% of the AW after flowering; and Stress 2 (S2) with 20% of the DAW before flowering and 40% of the AW after flowering. Measurements were taken throughout the day at different stages of growth. The results show that there were differences in the rl, rs and TL between genotypes and between water levels, especially during the afternoon. The major differences were found between treatments S1 and S2 during reproductive development. BAT-477 and SER-16 had the highest rs values, 267.2 ms^-1 and 257.6 ms^-1 respectively, under the S2 treatment, while SER-21 and Morales showed values of 153.3 ms^-1 and 214.4 ms^-1, respectively, under the same conditions, and under no-stress SER-21 had 130.9 ms^-1, Morales 151.8 ms^-1, SER-16 157.7 ms^-1 and BAT-477 164 ms^-1 Values for stomatal resistance showed the same tendency as surface resistance, TL had linear relationship with air temperature and the slope increased with the water stress, and had a polynomial relationship with rl.

Keywords: Common bean, Drought, Stomatal resistance, Surface resistance, Leaf temperature

HORT 6 - Influence of drip irrigation and nitrogen rates on strawberry cultivars. B. M. Santos, E. H. Simonne, J. R. Duval, E. A. Golden, and A. J. Whidden. Gulf Coast REC, IFAS, University of Florida.

Current recommendations for nitrogen (N) fertilization and drip irrigation greatly differ from those used by most strawberry growers. Three field trials were established during winters of 2003, 2004 and 2005 to determine the effect of different drip irrigation and N rates on three strawberry varieties. In all seasons, drip irrigation rates were 60, 80, 100, and 120 gal/100 ft/week, and strawberry varieties were ‘Strawberry Festival’, ‘Ventana’, and ‘Winter Dawn’. During 2003 and 2004, N rates were 0.36, 0.48, and 0.60 lb/acre/day, whereas 0.36, 0.60, and 0.84 lb/acre/day were used in 2005. There were significant early and total yield differences among all three cultivars. However, there were no significant drip irrigation or N rate effects within each strawberry variety.

HORT 7 - Efecto de las prácticas de desmane y desdede sobre el tamaño de la fruta del banano (Musa AAA) clon Gran Enano. H. Ricardo, E. De Jesús y R. De la Paz. Instituto Dominicano de Investigaciones Agropecuarias y Forestales (IDIAF).

Los productores de banano utilizan el desmane y el desdede en el racimo para mejorar el tamaño de la fruta. Durante el período mayo–julio de 2005 se condujo una investigación en la Estación Experimental Azua del Instituto Dominicano de Investigaciones Agropecuarias y Forestales (IDIAF) para determinar el efecto de estas prácticas en banano cultivado bajo condición orgánica. Se utilizó un diseño completamente al azar con nueve tratamientos y cuatro repeticiones. Los tratamientos fueron la combinación de tres niveles de desmane (eliminación de cero, uno y dos manos de frutos verdaderos), y tres niveles de desdede (eliminación de cero, dos y cuatro frutos de los laterales de cada mano). Las variables medidas fueron longitud y grado de los frutos centrales externos de la primera y última mano del racimo. Los datos se procesaron mediante análisis de varianza y regresión. El número de hojas a floración y la cantidad de manos en el racimo se utilizaron como covariables. El número de hojas de la planta a la floración influyó sobre la longitud de los frutos de la primera y última mano; su efecto fue más significativo en el fruto de la última mano (P = 0.003) que en la primera mano (P = 0.03). En ambos casos la variación expresada por esta variable fue de 24%. El grado de la fruta en la primera mano dependió de la cantidad de manos del racimo (P = 0.002), las cuales influenciaron el 24% de la variación registrada en esta variable; a su vez el grado alcanzado por la fruta en la última mano fue influenciado por la cantidad de manos en el racimo y el desdede. El efecto del desdede fue menos significativo (P = 0.01) que la cantidad de manos en el racimo (P = 0.001). La cantidad de manos afectó el 24% de la variación registrada en el grado de la fruta de la última mano, en cambio el desdede solo influyó en el 18%. El desmane y el desdede podrían ser innecesarios debido a que en los racimos sin desdede ni desmane los frutos alcanzaron la longitud y el grado exigido para el mercado al cual los productores exportan la fruta.

HORT 8 - The effects of plant population on yield and fruit quality of hot pepper cv. Local Red. T. Indalsingh and P. B. Antoine. Ministry of Agriculture, Land and Marine Resources, Trinidad and Tobago.

Hot pepper cv. Local Red (Capsicum chinense) is one of the few agricultural commodities with potential for increased exports in Trinidad and Tobago, and has been selected as a priority crop under the Agricultural Sector Reform Programme. Typical farmer practice is to produce the crop at a relatively wide spacing of 1.5 m x 1.5 m (4,444 plants ha^-1). In 2004, a trial was conducted at the Central Experiment Station, Centeno, Trinidad, on a Long Stretch sandy clay loam (clayey kaolinitic Plinthic Tropaquults) to assess the effects of high plant populations on yield and fruit quality. A ramdomized complete block design comprised four plant populations; 27,777; 18,458; 13,888 and 6,944 plants ha^-1. Standard agronomic practices were adopted. Transplanting was done in December 2003; 50% flowering was observed at 63 days, and harvesting was done over the five-month period April to August. The results showed that at 27,777 plants ha^-1, yield was 150,000 kg ha^-1 as compared with 45,800 kg ha^-1 for the lowest population. Fruit size was not significantly affected by plant population; neither was number of days to 50% flowering. Plant height increased with an increase in plant population, and a reduction in fruit size with age was observed. Utilizing a high plant population production system has the potential for increasing hot pepper yield without compromising fruit quality.

HORT 9 - Evaluación de germoplasma de Heliconia stricta en Puerto Rico. L. R.Santiago¹ y A. J. Beale². ¹Departamento de Horticultura. ²Departamento de Agronomía y Suelos. Universidad de Puerto Rico, Estación Experimental Agrícola.

La empresa de plantas ornamentales aportó $46.7 millones al ingreso bruto agrícola total de la isla en el año 2004-2005, según datos preliminares del Departamento de Agricultura. Las plantas ornamentales representaron el segundo cultivo agrícola en importancia económica en Puerto Rico. Las flores de corte solo aportaron un 3% de la producción local, ya que la mayor parte son importadas. Las heliconias son flores tropicales exóticas con gran demanda para el mercado local y de exportación. Por lo llamativo de sus colores, éstas son plantas muy utilizadas en jardines exteriores, como plantas florecedoras en tiesto, y como flores de corte. No existen estudios detallados sobre producción y cultivo de heliconias en Puerto Rico. Se diseñó un experimento para evaluar el desempeño de diferentes variedades de Heliconia stricta en Puerto Rico. El experimento se realizó en cajas sementeras en las facilidades de la Estación Experimental Agrícola de Río Piedras. Las variedades evaluadas fueron Iris Banochie, Buckey, Fire Bird, Canary Yellow, Dorado Gold, Oriole Orange, Pasquita, Valentine, Red y Dwarf Jamaican. El diseño del experimento fue de bloques completos al azar con tres repeticiones. Las variedades se propagaron por rizomas, se sembraron en tiestos de un galón y al cabo de dos meses se trasplantaron a las cajas sementeras. Se evaluó el tiempo de floración, número de hijos, altura de la planta (mensualmente), área de extensión de los hijos, comportamiento de crecimiento, número de flores, tamaño de inflorescencia, ancho de inflorescencia, peso de la inflorescencia y número de brácteas. Las variedades Iris Banochie, Buckey, y Fire Bird demostraron tener un crecimiento invasivo ya que los hijos ocuparon mayor área de extensión. Las variedades Dwarf Jamaican, Pasquita, Canary Yellow y Valentine exhibieron un crecimiento no invasivo. Las variedades que florecieron en menor tiempo fueron Dwarf Jamaican, Dorado Gold e Iris Banochie. Al cabo de un año las variedades Canary Yellow y Fire Bird aún no han florecido. El mayor número de flores se observó en las variedades Dwarf Jamaican y Valentine. Las variedades con mayor número de hijos demostraron ser Dwarf Jamaican, Pasquita y Valentine. La variedad Iris Banochie alcanzó la mayor altura y produjo la inflorescencia más larga, ancha y de mayor peso que el resto de las variedades estudiadas. El número de brácteas se mantuvo entre tres y siete por inflorescencia.

HORT 10 - The generic tree-soil-crop interaction model WaNuLCAS for the evaluation of multi-species agro-ecosystems in the tropics: A case study with banana (Musa spp.) H. Ozier, G. Damour, R. Tournebize, and B. Lusiana. Institut National de la Recherche Agronomique (INRA).

Multi-species tropical cropping systems including agroforestry, intercrops and cover crops are presently considered of pivotal importance for the development of sustainable agro-ecological low input systems that respect human health and the environment. The biological efficiencies that mixed species or genotypes are expected to develop with their environment depend on appropriate management practices that must be adapted to farmers’ possibilities. Existing agronomic experience may not be sufficient to assist such farmers in predicting the consequences of their trial-and-error approach. A flexible tool is desirable for evaluating the effects of a wide range of initial soil conditions, fertilizer levels, and intercropping practices on the yields and environmental status to be expected. The paper describes the application of the generic tree-soil-crop interaction model WaNuLCAS (Water, Nutrients and Light Capture in Agroforestry Systems) to the case of banana (Musa acuminata) intercropped with a leguminous crop Canavalia ensiformis. Once properly parameterized, the combined model can be used for evaluating scenarios of cultivating banana in combination with other crops in different environmental conditions; the model provides a predictive understanding of how the banana tree is likely to interact with other plants, directly or indirectly via modified availability of soil, water, and nutrient resources. In the context of the Caribbean banana crisis, such an approach may be very helpful to assist decision making for the optimization of alternative low input banana cropping systems.

HORT 11 - Caracterización y nivel de desorción de volátiles generados por la cocción de pulpa de batata. J. A. Dumas y C. Ortiz. Universidad de Puerto Rico, Estación Experimental Agrícola.

Las batatas son un cultivo de importancia comercial en la región del Caribe. Este cultivo genera volátiles que pueden ser utilizados para determinar la calidad entre las variedades. En este estudio se caracterizaron los volátiles liberados durante la cocción en agua caliente de ocho variedades de batatas y se determinó el nivel de desorción de algunos de los compuestos identificados. La identificación de volátiles se hizo mediante la técnica de “static headspace” (SH) acoplada a microextracción en fase sólida (SPME). Esta técnica permitió el análisis de los volátiles en una atmósfera rica en humedad y contenido de dióxido de carbono. Las variedades estudiadas fueron Ninetynine, Pujols, Taiwan, Martina, Dominicana, Dune, Craneal y Miguela. En un envase de 20 ml se colocaron 10 g de una pasta compuesta de pulpa y agua en proporción 1:1. La muestra se enriqueció con etil benzoato como estándar interno, a un nivel de 10 ng/g. El envase se selló y calentó a 80° C por una hora, y luego una fibra acondicionada de polidemetil siloxano se expuso por una hora adicional al SH de la muestra. Los compuestos adsorbidos en la fibra se analizaron por GC-MS. Se observó la presencia de hexanal, benzaldehído, 2-pentilfurano, isoledeno, copaeno y humeleno en todas las variedades de batatas. Los compuestos separados en una columna analítica DB-5MS de 30 m tuvieron índices de Kovats de 501, 860, 887, 1258, 1268 y 1342, respectivamente. Las isotermas de desorción de los terpenos isoledeno, copaeno y humeleno adsorbidos en la pasta de batata presentaron un proceso de equilibrio inicial favorable. La desorción de los aldehídos hexanal y benzaldehído hacia la fase gaseosa fue superior a la de las muestras testigo en el intervalo de concentraciones de 10 a 200 ng/g. Se deduce que los terpenos son compuestos estructurales mientras que los aldehídos antes mencionados son generados durante el proceso de cocción de estas variedades. Estos resultados ayudan a caracterizar mejor estas variedades de batatas y pueden ser utilizados para obtener un índice de selección cuantitativo.

Roots and Tubers (R&T)

R&T 1 - Gustos y preferencias por raíces y tubérculos en Puerto Rico. M. Cortés y L. Gayol. Universidad de Puerto Rico, Estación Experimental Agrícola.

Se entrevistaron 330 consumidores en los Supermercados Amigo con el objetivo de conocer sus preferencias por el consumo de raíces y tubérculos. El consumidor prefiere consumir yautía, 40%; ñame, 24% y yuca, 19%. De los entrevistados el 54% indicó consumir algún tipo de raíz o tubérculo semanalmente. El 31% consumía raíces y tubérculos mensualmente y el 9% diariamente. El 87% adquiere el producto en el supermercado y el 18% en la calle. El gasto promedio mensual ascendió a $18.95. El 87% prefería comprar de forma fresca las raíces y tubérculos que consumía. Entre las características deseables en el producto, 24% de los encuestados mencionaron la frescura y el 21%, la apariencia. El 53% no sabe diferenciar entre el producto local y el importado. Solo 24% de los menores de seis años consumen raíces y tubérculos. El 77% encuentra diferencias entre el producto local y el importado y prefiere comprar el local. Al preguntarles la razón por la que prefieren los farináceos del país indicaron que los del país tienen mejor sabor (29%) y son más frescos (22%). Al momento de comprar raíces y tubérculos los consumidores lo hacían porque eran saludables, 41%; le gustaban, 32%; es una tradición puertorriqueña, 13%; y es un sustituto del arroz, 7%. El 99% respaldaría una industria local. El tamaño promedio de la familia de tres miembros. En cuanto al nivel de estudio de los entrevistados, 40% alcanzó escuela superior (grado 12 o menos), 34% tenía un bachillerato sin finalizar, 23% tenía bachillerato, y solo el 3% tenía maestría o doctorado. En el 65% de las familias la compra de raíces y tubérculos estaba a cargo de la mujer; el 63% recibía algún tipo de ayuda gubernamental.

R&T 2 - Distancia de siembra y fuente del material de propagación en el rendimiento de yautía (Xanthosoma spp.) en la zona central de Puerto Rico. A. González. Universidad de Puerto Rico, Estación Experimental Agrícola.

Se determinó el rendimiento y el peso promedio de cormelos mercadeables de yautía Estela (Xanthosoma sagittifolium x Xanthosoma atrovirens) utilizando dos distancias de siembra (1.3 m x 0.46 m y 1.3 m x 0.30 m) y dos fuentes de material de propagación (cormos madres de diámetro mayor de 8.9 cm o menor de 7.6 cm). Además, se determinó el número promedio de cormelos mercadeables, cormelos no mercadeables y cormelos brotados por planta. El experimento se estableció utilizando un diseño de bloques completos al azar con cuatro repeticiones. Los datos se analizaron usando un modelo de análisis de varianza para dos factores. Los resultados muestran que no hubo diferencia significativa, ni interacción entre factores para rendimiento y peso promedio de cormelos mercadeables. El mayor rendimiento (11,322 kg/ha) se obtuvo cuando la yautía se sembró a una distancia de 1.38 m x 0.30 m, utilizando material de propagación de cormos madres de más de 8.9 cm de diámetro. La distancia de siembra afectó significativamente el número de cormelos brotados por planta; a menor distancia de siembra menor el número de cormelos brotados por planta. Ni la distancia de siembra ni el tamaño del material de propagación afectaron significativamente el número de cormelos mercadeables y no mercadeables por planta. Tampoco se observó interacción entre estos factores.

R&T 3 - Evaluación de características hortícolas asociadas al rendimiento de la yuca (Manihot esculenta). M. Díaz¹ y M. L. Lugo². Universidad de Puerto Rico, ¹Servicio de Extensión Agrícola, ²Estación Experimental Agrícola.

La yuca es uno de los cultivos de mayor importancia económica en los trópicos y subtrópicos. Aunque de fácil manejo agronómico, presenta su mayor dificultad al momento de la cosecha. Se estima que en Puerto Rico se consumen anualmente 163 mil quintales de yuca pero sólo se produce el 7% de esa cantidad. Es necesario evaluar nuevas variedades o selecciones de yuca para mercado fresco, incluyendo aquellas consideradas como nichos de mercado, como lo es en Puerto Rico la yuca de pulpa amarilla, para brindarle nuevas alternativas de producción al agricultor. Para que las variedades que se seleccionen sean aceptadas por el consumidor, una de las características que deben tener, especialmente si son de pulpa blanca, es la de pelado o mondado fácil. Los resultados de este experimento demuestran que estadísticamente las variedades Cm-3064, Jamaica-18 y la selección de pulpa amarilla superaron en rendimiento por peso comercial a la Serrallés y Valencia, respectivamente. Serrallés es la variedad que más se produce en Puerto Rico y Valencia la que más se importa. En los otros parámetros evaluados (número comercial y no comercial de raíces, peso de raíces no comerciales y peso total de raíces) no hubo diferencias significativas entre las variedades. Cabe señalar que las variedades con el mejor rendimiento presentaron el mayor grado de dificultad en cuanto al pelado o mondado de la raíz lo que dificultaría su entrada al mercado local y más aún, su aceptación por el consumidor.

R&T 4 - Cloning and Characterization of β-cyanoalanine synthase in cassava: An avenue for both cyanide detoxification and enhanced amino acid content. J. Marrero and D. Siritunga. Department of Biology, University of Puerto Rico, Mayagüez Campus.

Cassava (Manihot esculenta) is a starchy root crop cultivated in tropical America, Asia and more extensively in sub-Saharan Africa. It is the most agronomically important of the cyanogenic food crops. Cyanogenic glycosides can release cyanide after enzymatic breakdown. Certain health disorders such as tropical ataxic neuropathy and konzo, a paralytic disorder, have been associated with poorly processed cassava diets. The key enzyme that allows cyanide detoxification in cassava is β-cyanoalanine synthase (β-CAS). This enzyme belongs to the β-substituted alanine synthases (Bsas) family, and catalyzes the incorporation of cyanide to asparagine and aspartate biosynthesis pathway. β-CAS is located in the mitochondria, where it prevents the lethal action of cyanide on the electron transport chain. The β-CAS pathway provides an ideal way to develop a protein-rich transgenic cassava plant coupled with low cyanide content. However, the cassava β-CAS sequence has not yet been identified. This research project aims to determine the cassava β-CAS cDNA sequence in order to develop a transgenic cassava plant with cytosolic over-expression of the β-CAS gene. This is expected to facilitate the encounter between β-CAS and cyanide from the cyanogenic glycoside pathway. Successful isolation of leaf β-CAS cDNA sequence was achieved by using the PCR-based rapid amplification of cDNA ends (RACE) method. Primers used were designed using a partial cassava β-CAS EST sequence and the β-CAS gene of the rubber tree. Interestingly, 3’RACE PCR has revealed the presence of three different β-CAS genes, alluding to the presence of multiple members of Bsas family in cassava. Efforts are also being directed towards the RACE amplification of the 5’ end. This will clarify the number of different β-CAS related genes present in cassava, as the principal differences between these genes are in the 5’ signal peptide coding region. Complete sequence data (including 5\' and 3\' UTR) of the cassava β-CAS gene will be presented.

R&T 5 - Evaluating sweet potato (Ipomoea batatas) for utilisation properties. P. Titus¹, N. Ali², J. O. Akingbala². ¹Caribbean Agricultural Research and Development Institute (CARDI) St. Vincent and the Grenadines; ²Department of Chemical Engineering, University of the West Indies, St. Augustine, Trinidad.

Twenty-one sweet potato cultivars are currently being evaluated for market acceptance, yield and resistance to pests and diseases at CARDI experimental station in St. Vincent and the Grenadines. Based on market demand, the most acceptable varieties were the red skinned, white fleshed, Black Vine and Big Red; the least acceptable was the carrot-coloured Lover’s Name variety. The three varieties were evaluated for Crisps and Fries properties. Frying conditions (slice thickness, frying oil temperature and residency times) for preparation of crisps and fries were optimised. Desirable properties of crisp and fries were determined. Sensory scores of appearance, taste, texture and general acceptability based on a scale of 5= like extremely, to 1= dislike extremely, were used to determine product quality. Also texture of the products was determined with the penetrometer. Potato crisp consumers (36%) preferred pale brown colour, 24% preferred deep yellow, whereas others (21%) had no preference for colour. Consumers preferred sweet, 52%; very sweet, 2%; and salty, 38%, sweet potato crisps. Almost everyone (92%) preferred crispy crisps. The preferred colours for potato fries were deep yellow and pale brown; the preferred taste was sweet (50%) or salty (39%); the preferred texture was crisp, though, some (22%) liked soft fries. The overall acceptability score of fries from the three sweet potato varieties was below average (3.0) with no preference among varieties. Texture, colour and taste were generally scored lower than 3.0. Although the varieties were better suited for crisp production, there was no difference among sensory performances of the varieties. Objective texture measurement of the samples indicated that fries from the Black Vine variety were hard (2.32 mm), whereas fries from Lovers Name (8.78 mm) and Big Red (8.22 mm) were softer. Crisps from all the varieties were very hard (0.00 mm).

R&T 6 - Effect of seed sett weight of ginger (Zingiber officinale) on yield. A. J. Beale, L. Ramírez, M. Díaz, M. Muñoz, and C. Flores. University of Puerto Rico, Agricultural Experiment Station.

Six weight ranges of ginger seed setts (14 to 28 g, 29 to 43 g, 44 to 57 g, 58 to 85 g, 86 to 114 g, and 115 to 128 g) were evaluated for yield in Gurabo, east-central Puerto Rico. The soil in the experimental area is of the Mabí clay series (fine, montmorillonitic, isohyperthermic Vertic Eutropepts). Rainfall during the nine-month cycle of the ginger (March-December 2005) was 1,744 mm (68.6 in) and drip irrigation was also provided on a regular basis. No significant differences in yield were found between the two heaviest seed sett weight ranges used for planting, 115 to 128 g and 86 to 114 g; the 115 to 128 g setts yielded higher α=0.05) than the remaining four ranges. The average yield of the 115 to 128 g setts was 24.59 mt/ha, whereas that of the 86 to 114 g setts was 18.47 mt/ha. The 86 to 114 g setts yielded significantly higher than the 14 to 28 g and the 29 to 43 g setts. Results indicate that the seed sett weight range of 86 to 114 g is the most economically feasible weight for planting ginger in east-central Puerto Rico.

R&T 7 - Safer cassava food: The production of transgenic cassava with accelerated cyanogenesis. D. Siritunga¹ and R. Sayre². ¹Department of Biology, University of Puerto Rico, Mayagüez Campus. ²Department of Plant Cellular and Molecular Biology, The Ohio State University.

Cassava (Manihot esculenta) is the major food crop for subsistence farmers in the tropics. Though valued for its ability to grow in adverse environments and the food security it provides, cassava contains potentially toxic levels of the cyanogenic glucoside, linamarin. Linamarin and its deglycosylated product acetone cyanohydrin can be effectively removed by various extensive processing methods. Shortcuts in processing, prevalent during times of famine, can lead to only partial removal of cyanogens. Consumption of foods with residual cyanogens results in neurological disorders and paralysis, particularly in nutritionally compromised individuals. To address this problem, we produced transgenic cassava plants by over-expressing the hydroxynitrile lyase (HNL) gene, which has accelerated cyanogenesis and cyanide volatilization during food processing. HNL, which catalyzes the conversion of acetone cyanohydrin to cyanide, is expressed predominantly in the cell walls and laticifers of leaves. In contrast, roots have very low levels of HNL expression. We have over-expressed HNL in transgenic cassava plants under the control of a double 35S CaMV promoter using Agrobacterium-mediated transformation. We showed that HNL activity increased more than two-fold in leaves and 13-fold in roots of transgenic plants relative to wild-type plants. Elevated HNL levels were correlated with substantially reduced acetone cyanohydrin levels and increased cyanide volatilization in processed or homogenized roots. Importantly transgenic plants overexpressing HNL in roots retained the herbivore deterrence of cyanogens while providing a safer food product.

R&T 8 - Developing systems for sustainable production of export grade dasheen [Colocasia esculenta (L.) Schott var. esculenta] in Dominica. G. C. Robin. Caribbean Agricultural Research and Development Institute (CARDI).

In Dominica the sustainable production of export grade dasheen corms was constrained by incorrect projections, resulting from a lack of detailed understanding on how agro-ecological zones, seasonality and agronomic practices have an impact on corm yield and shape. Experiments addressing the above examined the effects of planting depths and spacing on corm yield and shape. The experiments were conducted during both wet and dry seasons, in Grand Bay on soils characterized as plastic sticky clay loams without a silica pan, a moisture supply capacity which is low to very low and an average annual rainfall of approximately 2,400 mm (zone D3), and in the Wet Area on soils characterized as sandy clay loams, a moisture supply capacity which is moderately high, and an average annual rainfall of 5,300 mm (zone A2). Results showed that average corm weight per plant of 946 g and 995 g and mean yields per hectare of 12.9 and 14.1 t that were obtained in Grand Bay and Wet Area during the wet season, were not significantly different. In the dry season, Wet Area plant (913 g) and per hectare yield (12.3 t), were much higher when compared to plant (645 g) and per hectare yield (7.9 t) obtained in Grand Bay (P<0.01). Generally corm shape was oval in the Wet Area and irregular (Dumb-Bell) shape in Grand Bay. In Grand Bay variation in plant spacing was the major factor influencing yield and shape, whereas in Wet Area both spacing and depth interactions influenced yield and shape. Sustainable production of export grade corms was suited to Wet Area and areas with similar agro-ecological characteristics. In Grand Bay, production should be restricted to the wet season.

Keywords: Colocasia esculenta, Plant spacing, Planting depth, Agro-ecological zones, Seasons, Yield

General Agriculture (GENAG)

GENAG 1 - The importance of agricultural research institutions in Suriname. L. Ori. University of Suriname.

As a member of CARICOM, Suriname also exports rice, shrimp, timber, bananas and vegetables. Because of its richness in natural resources, Suriname has attracted the attention of companies and is also actively seeking international partners for joint ventures in oil, gold, and diamond explorations and exploitations. Often, many companies especially from Asia have expressed a lot of interest in the development of a hardwood industry in Suriname. In general, agricultural research institutions in Suriname have years of experience in the agricultural and forestry sector. Some agricultural research institutions have focused their research programs on wood processing technology, tissue culture, medicinal plants, fisheries/aquaculture, rice, fruits, and vegetables. As a major agricultural exporter in CARICOM, Suriname views its research institutions more challenged than ever to engage in agricultural research using the latest advances in order to increase production levels while ensuring higher quality and environmentally safe foods. This paper will evaluate the impact of agricultural research institutions in Suriname and the region over the last ten years. Data will be gathered by using the literature review, agricultural policy reports, interviews, and a mail questionnaire. Appropriate statistics will be used in data analyses and interpretation. Results of this study will show that research institutions in Suriname can also play an important role in the development of the region.

GENAG 2 - An assessment of agricultural education in Suriname. L. Ori and L. Soetosenojo. University of Suriname.

Keywords: Agricultural education, Agricultural training, Formal and non-formal education

Caribbean AgroEconomic Society (CAES)

CAES 1 - Puerto Rico’s Agricultural Economy: From Traditional Agriculture to Value Added Agriculture. G. González. Associate Dean, Faculty of Agricultural Sciences, Mayagüez Campus of the University of Puerto Rico.

CAES 2- CARICOM countries agricultural sector competitiveness position with reference to the export of specialty crops to the US import market. G. G. Lowe and C. G. Davis. Food and Resource Economics Department, University of Florida.

For the small island economies of CARICOM, the agricultural sector has been an important component of economic development, supported particularly by the production of traditional export crops under protected markets. The imminent loss of preferential access to the European market granted under the Lomé convention, and the rapidly liberalizing trade environment within the western hemisphere, evidenced by the brokering of bilateral/plurilateral free trade areas (FTAs) within the hemisphere, signify major changes in the agricultural trading environment. These changes indicate a transitioning from the existence of protected domestic and assured international agricultural markets to participation in a competitive environment of liberalized trade. If CARICOM’s agricultural sector is to thrive in the changing environment there has to be a continuous systematic evaluation of market opportunities and competitiveness supporting the development of policies geared towards improving its competitive position. This evaluation, however, requires a clear understanding of the multifaceted concept of competitiveness and the factors affecting it. This paper seeks to contribute to the regional discussion of competitiveness through the exploration of the theoretical and empirical dimensions of competitiveness within the context of CARICOM’s export of specialty crops to the United States. It strongly advocates market share analysis as a robust and powerful empirical tool for gauging competitiveness. Using trade data obtained from the United Nations (UN) Commodity Trade (COMTRADE) database covering the period 1991 to 2004, and a modified constant market share (CMS) model, developed by the Economic Commission for Latin America and the Caribbean (ECLAC) for their Module to Analyze the Growth of International Commerce (MAGIC) program, the competitiveness of commodities was determined. Initial findings suggested that CARICOM’s export of fresh produce to the US has generally not been competitive. This finding gives further credence to the pursuit of developing value added commodities. However, whether the focus is on primary production or value added commodities, a suggested path towards increased competitiveness is that of greater focus on marketing.

CAES 3- Alternatives to sugar cane in St. Kitts: Competitiveness studies of four crops in St. Kitts/Nevis. A. Edwards¹ and A. Jacque². ¹Ministry of Agriculture, St. Kitts, ²Ministry of Agriculture, Food and Marine Resources, Trinidad and Tobago.

The sugar industry in the island of St. Kitts came to a close in 2005 and so, too, did a long period of monoculture and possibly a culture and lifestyle of a people that affectionately refer to the country as Sugar City. Sugar was cultivated on approximately 4,500 hectares and there is now a dire need for replacement commodities that fit within the social, economic and environmental landscape of the country. Sugar cane cultivation and sugar production provided good paying jobs and was the main source of income for many households. The crop provided a high degree of soil conservation and was a boom to the tourism industry. In addition, sugar was a substantial source of foreign exchange and provided some diversification to a tourism-dependent economy. In selecting alternatives to sugar, the social, economic and environmental considerations must take into account the issues presented by globalization and trade liberalization. The Government has started the process by approving an externally funded Stevia project and by announcing plans for methanol production and co-generation of electricity from sugarcane. However, attention also is being drawn to some non-sugar commodities that were grown on St. Kitts on a small scale during the sugar dominant period. It is felt that these may be competitive on the international market thereby providing employment and foreign exchange, while catering to the needs of the rural population. This research will assess four of the non-sugar agricultural commodities for which there already exists production cost data in order to determine profitability, international competitiveness and comparative advantage. The research will also provide policy recommendations for a more conducive environment for identified competitive commodities. The main hypothesis of this research is that commodities of (i) pumpkin, (ii) peanut (iii) sweet potato and (iv) onion grown under St. Kitts/Nevis conditions are internationally competitive. The main research tool will be the Policy Analysis Matrix (PAM). This tool will be used to assess the four commodities for international competitiveness and comparative advantage. The research will also involve the collection of secondary data and primary data input into the matrix and will determine the relative importance of these four commodities in St. Kitts. The results of the assessment showed that all four commodities are profitable, competitive and have comparative advantage. However, these features are highest for the export commodities of pumpkin and sweet potato and lowest for the import-competing products of onion and peanuts. The level of government support to gross farm revenues is 4% for pumpkin and sweet potato, 3% for peanuts and 12% for onions. Policy recommendations are for an expansion of production of the export commodities, although with efforts to reduce the impediments to market penetration.

CAES 4- Competitiveness of Jamaican tropical crops after implementing SPS measures. K. Hyatt. Ministry of Agriculture, Jamaica.

Every country has a responsibility to safeguard the health of its citizens. With the onset of globalization and the desire to significantly reduce barriers to trade, numerous sanitary and phytosanitary measures have been instituted to ensure that goods imported into a country’s market satisfy the most stringent health standards. A number of interest groups, however, have expressed serious concerns regarding the impact of SPS measures on trade as it is thought that the SPS requirements of some developed countries put a constraint on the ability to export agricultural and food products. In fact, many developing countries consider SPS requirements to be among the greatest impediments to trade. In Jamaica’s case, a number of measures have been implemented to satisfy the SPS requirements of our trading partners. Pre-clearance facilities and residue testing labs have been established at considerable cost to local farmers and exporters. The high cost of instituting these measures has ultimate impact on the cost of production of the crops/commodities involved. Given the considerable cost of implementation of these measures, it is unclear whether Jamaica and other small developing countries can institute them and remain competitive. In keeping with the theme of the conference “Food Safety and Value Added Production and Marketing of Tropical Crops”, this paper will examine Jamaica’s ability to remain competitive in the production and marketing of selected tropical crops, after incurring the cost of implementing SPS measures. The hypothesis, therefore is, “Jamaica may not be competitive in certain tropical crops after incurring the cost of implementing the required SPS measures”. A qualitative as well as a quantitative approach will be adopted to establish a result. This will entail an examination of the policies agreed to by trading partners, soliciting the views of all stake holders: farmers, exporters, importers, consumers, agricultural professionals and academics.

CAES 5- A competitiveness study of rice production systems in Trinidad and Tobago. D. Seecharan and A. Jacque.

Rice imports into Trinidad and Tobago in 2005 represented approximately 95% of local demand. Domestic production has been declining since reaching a peak of 21,000 tonnes in 1992. The decline since 1992 followed the introduction of a grading system with guaranteed prices and subsidies that were intended to address the poor quality of paddy produced. Rice is produced under a variety of production systems and farm sizes with varying productivity and quality of output. Domestic producers compete with easily obtained imports from regional and extra-regional sources. This research paper examines the competitiveness of four production systems used in the industry, viz.: transplanted, high labor intensive system (small farm); broadcast seeded system (small-medium farm); the fully mechanized system (inclusive of aerial seeding, fertilizing and spraying); and a direct seeded mechanized system of less high technology usage. The objective of the research is to determine the international competitiveness of the three rice production systems. The hypotheses specify that the labor intensive system is not internationally competitive unlike the other two systems. The hypotheses also specify that none of the three production systems hold comparative advantage. The methodology involved the collection of data on revenue and cost of production and analysis using the framework of the policy analysis matrix (PAM), which allowed estimation of the indicators of policy effects, competitiveness and comparative advantage. Additionally and through consideration of other relevant data and information, the paper will provide policy recommendations for the industry.

CAES 6- Understanding the decline of cocoa production in Trinidad and Tobago. L. Neptune and A. Jacque, Ministry of Agriculture, Land and Marine Resources, Trinidad and Tobago.

Trinidad and Tobago produces a fine flavour cocoa that attracts a premium price on the international market. The country has a long and distinguished record in agronomy and production of cocoa and is home to the Cocoa Research Unit, which attracts international notice and funding. However, cocoa production has been on a steady decline over the past few decades. The objective of this study is to assess the competitiveness and comparative advantage of cocoa production in Trinidad and Tobago and to understand the reasons for decline in output. The hypotheses to be tested relate to the international competitiveness and comparative advantage of cocoa production and to the reasons for decline of cocoa production. The analysis will be conducted over three production systems –small farm traditional, large farm traditional, and large farm intensive cultivation. The methodology will involve collection of data and use of the framework of the Policy Analysis Matrix (PAM) to assess competitiveness and comparative advantage. Additionally, a sample of farmers will be interviewed to determine other reasons for declining output. Preliminary analyses indicate that all production systems are profitable, internationally competitive and have comparative advantage. However, the traditional small-farm production system has the least profitability, competitiveness and comparative advantage. The results suggest that the low levels of profitability per hectare for the small farms may underlie the declining area and output. The economic analyses will be supplemented by the survey data.

Keywords: Cocoa production decline, Trinidad, Tobago, Policy Analysis Matrix

CAES 7- An approach to measuring the true contribution of the agricultural sector to the economy. E. Harry. Inter-American Institute for Cooperation of Agriculture (IICA).

The paper postulates that the GDP, the traditional approach to measuring the contribution of the primary agricultural sector, grossly underestimates the real contribution which the sector makes to the economy. The study further postulates that the sector’s real contribution is undervalued because agricultural GDP does not take into account, in particular, the backward and forward linkages of the sector with other sectors of the economy. The procedure selected to highlight the real contribution of the agricultural sector to the economy was largely based on the construction of a Social Accounting Matrix (SAM) that was done for Trinidad and Tobago, based on 2000 data. With the use of the SAM data, four methods were used to quantify the real contribution of the primary agricultural sector to the economy. These methodologies included the use of gross output of primary agricultural production, distribution of costs in the production process, and construction of SAM multipliers to show the backward and forward linkages of the primary agricultural sector. The concept of “extendeded agriculture” is also brought into the analysis to further highlight other dimensions of the contribution of the agricultural sector to the economy.

CAES 8- The creation of non –traditional agribusinesses clusters and niche markets for sustainable development of Caribbean Agriculture. K. Amiel, Caribbean Broilers Group, Jamaica.

The paper looks at reinforcing traditional and non traditional commodity clusters by reorganizing them into vertically integrated groups, each containing essential elements of financing, adaptive research and development, grow out/ farming activities, differentiating and further processing, storage, branding supported by intellectual property rights, distribution and marketing with promotion and customer service backup. We will have a presentation on the project under the heading.

CAES 9- Trade liberalisation and Barbados’ special products: A closer look at four commodities. E. Marcus-Burnett. Agricultural Planning Unit, MAR, Barbados.

The World Trade Organisation (WTO), which governs over 90% of world trade, is often perceived as the biggest threat to Barbadian agriculture. WTO Members are currently engaged in negotiations to determine the new commitments in key areas, including agriculture. This paper examines four domestically sensitive products – cabbage, tomato, carrot and sweet pepper – and the impact of WTO trade liberalisation on the production and trade patterns of these commodities over the last twelve years. Particular emphasis is placed on the issue of Special and Sensitive Products and the implications for Barbados and Barbadian special/sensitive product. The aforementioned products are used as examples. The results for these four products were mixed. The analyses can be used to refine the strategic thinking regarding these four products and the results are of some relevance to other domestically sensitive commodities with similar characteristics. Furthermore, there are lessons to be learned as the CARICOM Single Market and Economy is deepened and as CARICOM negotiates bi-lateral trade agreements with various countries/groupings.

CAES 10- An approach to a microbiological risk assessment in the poultry sector in Trinidad. M. Dookeran, G. S. H. Baccus-Taylor and J. Akingbala. Food Science and Technology Unit, Department of Chemical Engineering Faculty of Engineering, University of the West Indies, St. Augustine, Trinidad.

International studies and epidemiological data have revealed a strong association between salmonellosis and broiler chicken meat. This association provides serious challenges for food safety, international trade and social stability. In Trinidad, the adverse effects and magnitude of salmonellosis from the consumption of broiler chicken meat is unknown, because of the lack of an active surveillance network. Additionally, the absence of specific standards and regulations to ensure microbiological criteria and food safety, in one of the country’s largest agro-processing industry, has led to conditions that may contribute to the high incidence of Salmonella infection. If these conditions are allowed to proliferate unchecked, consumers may be at risk of food borne infection, illness and death. This scenario may result in the broiler industry’s economic decline. Microbiological Risk Assessment is a food safety tool that is used to reduce the incidence of food- borne illnesses. The process identifies a microbiological hazard in the entire food continuum (from farm to fork) and estimates the adverse effects to human health of ingesting the microbial hazard. The assessment integrates four steps, to produce a practical estimate of risk: hazard identification, hazard characterisation, exposure assessment and risk characterisation. In each step, knowledge of the prevalence and concentration of the pathogen, and the probability and magnitude of health effects, are combined to represent a cause and effect chain. In this risk assessment, Salmonella and broiler chicken meat are linked to human illness from the evaluation of epidemiological data. Additionally, sampling and analysis of chicken meat and the farm environment are instituted to estimate the source and frequency of Salmonella. A dose-response model is created by using data obtained by sampling and analysis or historical epidemiological data. In the exposure assessment, data on the levels of Salmonella at the risk-determining stages are analysed. Predictive or kinetic (sub) models are used to estimate the changes in the behaviour or levels of pathogens in the food prior to consumption. Finally, the risk characterization module integrates the information derived from hazard identification, hazard characterization and exposure assessment, to produce an estimate of the probability of salmonellosis from the consumption of broilers.

CAES 11- Food safety management systems: Initiatives of Trinidad and Tobago, West Indies, Philippines and Bangladesh. N. Badrie¹, S. Y. De Leon² and R. Amin³. ¹ Department of Food Production, Faculty of Science and Agriculture, University of the West Indies, Trinidad and Tobago, ²Department of Food Science and Nutrition, University of the Philippines, Diliman, College of Home Economics, Quezon City, Philippines, ³ Food Planning and Monitoring Unit, Ministry of Food and Disaster Management, Government of Bangladesh.

International trade is an important element in the economic development of all countries. Protecting human health in today's global food market is an important challenge and one which must be addressed through internationally recognized food safety systems. The overall responsibility for food safety is shared by all segments of the food system, including the various industry sectors, government regulatory agencies and consumers in general. Any threat to the food supply, whether by intentional or unintentional contamination, could result in danger to health, considerable cost to food chain suppliers and could also affect trade. This paper will highlight some initiatives of three countries --Trinidad and Tobago, the Philippines, and Bangladesh-- in protecting the food supply from hazards by applying food safety management systems. The initiatives of some non-governmental organizations in Trinidad and Tobago are discussed. In the Philippines both the public and private sectors are active in encouraging strict adherence of the food industries to food safety systems. A non-government agency has successfully used inventions and innovative training kits under the “4-in-1 Food Safety Training system: 5S, GAP (Good Agricultural Practice), GMP (Good Management Practices) and HACCP (Hazard Analysis Critical Control Point)” in the last decade to help the food industries meet the safety and quality requirements of national and international trade. Also discussed are some food safety regulations implemented all over the Philippines to insure safety. Also highlighted are challenges and opportunities for Bangladesh of the frozen fish trade through implementing principles of HACCP and some food safety legislations.

CAES 12- The process towards the development of an improved national food safety system in Antigua and Barbuda. J. A. Laudat. Inter-American Institute for Cooperation of Agriculture (IICA), Antigua.

In 1999, the need for improvements in the food safety system of countries of the Caribbean was recognized in a meeting of CARICOM Ministers of Agriculture in Barbados. A properly functioning food safety system should ensure that all food consumed in a country, whether produced locally or imported, and also food exported from that country, should conform to acceptable standards that would ensure the health and safety of the consumers. In Antigua and Barbuda in 2000, an ad hoc National Food Safety Committee was set up with the following goal: To ensure that all food and water consumed in Antigua and Barbuda, whether imported, produced locally or for export, conform to acceptable standards to ensure the health and safety of the consumer. Some of the activities undertaken by this committee were training of local food handlers and processors, farmers; updating of legislation on food safety; educating the public on safe food practices; improving the food inspection service. The local system is currently characterised by many different agencies, ministries and organisations with responsibilities for food safety, with very little coordination or collaboration. In improving the food safety system in Antigua and Barbuda, it was recognised early that there was an urgent need to revise legislation related to food safety. Over the last six years, the National Food Safety Committee has been able to finance projects to develop a new Food Safety Act, to revise Plant Health and Animal Health Acts and a Toxic Chemicals and Pesticides Act, as well as, to conduct training in food safety and consultations on food safety matters. The next step for the government is to enact the formation of a coordinated centralised agency for food safety.

CAES 13- Factors that influence alcohol consumption in the Caribbean and Central America countries. C. Ligeon, P. Gregorowicz, and C. Jolly, School of Business at Auburn University Montgomery, Department of Agricultural Economics and Rural Sociology at Auburn University at Auburn.

Alcohol plays an important part in the diets and social activities of the people in the Caribbean and Central American countries. Over the period 1961 through 2003, alcohol consumption varied in these countries. The most preferable forms of alcoholic beverages in the Caribbean and Central American countries are spirits, followed by beer and wine. The average per capita consumption of alcohol in the Caribbean is 6.42 liters per year, whereas in the Central American countries it is 4.26 liters per year. With a per capita consumption of 13.6 liters of alcohol, the Bahamas has the highest alcohol consumption in the Caribbean, followed by Saint Lucia and Bermuda, with 10.2 and 9.85 liters, respectively. The countries with the lowest alcohol consumption in the Caribbean were Jamaica, Antigua and Dominican Republic. In the Central American region, Belize had the highest alcohol consumption, with 5.78 liters per capita, whereas Honduras had the lowest alcohol consumption with 2.14 liters per capita. The annual percentage consumption growth rate varied during the same period with a -0.91, -0.399, -0.28, -0.13% for Guatemala, Haiti, Belize and Suriname, respectively. Given the variation in the alcohol consumption in these regions over the years, it is important to evaluate the factors influencing the alcohol consumption in these countries.

CAES 14- Linking Hawaiian small agribusiness to the world via the World Wide Web. S. Shehata. University of Hawaii-Hilo.

The website, HawaiianAgriculturalProducts.com, is developed and run to help promote small growers market their products through the website, estimate their cost of production, and improve their management and marketing skills. It is essential in helping small farmers become prosperous in today’s competitive agribusiness market. The website currently lists growers’ websites by commodity and improves a grower’s chance of being found in search engines such as Google. Buyers can log on and order directly from participating growers. The website will be used as a training site for native Hawaiian, rural, underprivileged high school students and their families to help in marketing their products and improve their chances for business success. Telephone and personal interviews are conducted with growers across the State of Hawaii in order to determine the costs associated with producing potted orchids by each variety. We used the orchids as a case study for other crops. All listed growers are identified and contacted to determine their willingness to participate. In order to protect the identity of the growers, the number of growers interviewed in each category is not disclosed. Production coefficients are estimated on the basis of the information provided by the growers surveyed and validated with researchers and previous publications. These coefficients are kept constant in estimating the cost of production. Variable and fixed costs are included in the cost of production model. After the data is collected, the database is developed and the results are tested with existing farm operations. The computer program is then developed by using JavaScript and PHP, and uploaded to the website. Individuals can then estimate cost of production at their leisure. The website features interactive cost of production programs that estimate production costs for each farm. These programs can be customized for many different crops. Eventually, the website will house an e-commerce clearinghouse to improve the distribution efficiency of Hawaiian products. This website is the first of its kind to do this type of analysis, and it could be duplicated by other universities as a model to serve their community. For a demonstration, please visit the website at http://hawaiianagriculturalproducts.com.

CAES 15- Marketing opportunities for Jamaica’s grapefruit industry. E. A. Evans, W. Nalampang, S. Nalampang and T. Spreen . University of Florida, USA.

Several Caribbean sugar-producing countries are actively looking for viable alternatives to recover some of the revenues to be lost because of the WTO (World Trade Organization) ruling that sugar subsidies in the European Union (EU) are illegal. One alternative worth considering is exporting fresh grapefruits to the EU. This marketing opportunity comes about as the United States of America (U.S.), the world’s leading grapefruit producer and exporter (over half of world production), has suffered a series of recent setbacks (citrus canker, citrus greening diseases, and devastating hurricanes) that threaten the future of that industry. Specifically, grapefruit and pomelo production in the U.S. has declined steadily since 2000 (from 2,506 thousand metric tons in 2000 to only 914 thousand metric tons in 2005). A recently released study conducted by the University of Florida (UF) on the economic impact of citrus canker and citrus greening diseases on grapefruit profitability points to a bleak future for the Florida citrus industry. Approximately 25% of U.S. fresh grapefruit exports are directed to Europe, which is the largest grapefruit and pomelo import region (nearly 60% of world grapefruit and pomelo imports). Rising grapefruit prices in the EU, due to reduced supplies coming from the US and an increase in the demand for the fruit in the EU, could create marketing opportunities for countries such as Jamaica. The paper discusses the state of the Florida citrus industry with particular reference to grapefruits and the marketing prospects for Jamaican grapefruit exports to Europe.

CAES 16- Market orientation and Caribbean agriculture: The case of St. Vincent and the Grenadines. A. Iton and P. Titus. Caribbean Agricultural Research and Development Institute (CARDI.).

Dramatic changes in Caribbean agricultural production and marketing are called for if agriculture is to return and remain a robust part of our economy. With unprecedented technological advancements, the rapid increase in consumer incomes and changing consumption patterns, low prices and an abundant supply no longer ensure a firm’s survival in the global marketplace. The answers to the contemporary threats to Caribbean agriculture lie in the development of innovative marketing strategies, new crops and products, and new ways to produce them. Increasingly, empirical research has demonstrated a positive relationship between market orientation and firm/organizational performance. Despite the strong empirical evidence that market orientation is a useful contributor to firm performance, there appears to be no investigation of this linkage in Caribbean agriculture. The purpose of this exploratory study is to develop a conceptual framework for measuring the market orientation of Caribbean farmers. Further, since the classic constructs of market orientation are derived from a North American perspective, it is hoped that this study would stimulate the interest of others to identify the usefulness of the market orientation construct in a Caribbean context, and where possible develop better measures of the concept.

CAES 17- The effects of pesticide use on human health in rural Jamaica. P. E. Jolly & N. Ngqabutho¹, C. Fogo & K. Tint², and C. M. Jolly³. ¹Department of Epidemiology, University of Alabama at Birmingham, Birmingham, AL, ²Westmoreland Health Department, Ministry of Health, Jamaica, Jamaica, West Indies, ³Department of Agricultural Economics and Rural Sociology, Auburn University, Auburn, AL.

Pesticide poisoning is a major pubic health concern in developing countries. Pesticides are synthetic or organic poisons that are applied predominantly to kill or control weeds, insect pests, nematodes, fungi and other organisms that attack agricultural plants and animals. During application, pesticides enter the bodies of humans and other animals. They also enter the systems of humans and other organisms through the air, soil, and food. An estimated 99% of human pesticide fatalities occur in developing countries, although these countries account for only 20 to 30% of pesticide use. In 1986 the WHO estimated that there were about one million cases of pesticide poisoning occurring annually. In Jamaica, a number of studies have detected high levels of pesticide (Endosulfan) residue in surface water and aquatic life, and acute pesticide poisoning is believed to be widespread in Jamaica. In 1999, the Jamaican government, with international organizations, created a “pesticide awareness week” where messages on pesticide safety are disseminated to all segments of the society. The government has also linked up with the Food and Agriculture Organization in adopting a safe pesticide disposal plan. Yet many farmers, especially the very poor, still have not internalized the dangers associated with poor pesticide handling to human health, and the general effects on the environment. This study will 1) describe the use (appropriate or inappropriate) of pesticides by farmers in northwestern Jamaica and summarize inappropriate methods used in handling pesticides; 2) report on the harmful effects of inappropriate pesticide use; 3) discuss the socio-economic, attitudinal and behavioral factors that influence inappropriate use of pesticides by farmers; and 4) present recommendations and outline strategies that can be implemented in order to improve pesticide use to reduce the deleterious effects of improper handling and use of pesticides on human and animal health.

CAES 18- Do benefits from foods influence perceptions towards organic and GMO foods? E. M. Tavernier, B. M. Onyango and C. E. Pray. Rutgers University.

This paper examines consumer willingness to buy organic or GM food products in the context of food benefits that are considered important in the consumption decision. In particular, the paper examines the process that shapes food preferences in the absence or presence of specific food attributes. The paper finds that food attributes related to health, naturalness, familiarity, vegetarian-vegan, production location, and availability are critical in the acceptance of the organic and GM foods. The results show that food naturalness is pivotal to the organic food purchasing decision, and the absence of allergenic-causing ingredients increases GM purchases. The findings also suggest that although there are perceived differences between organic and GM foods, the presence or absence of an attribute becomes important only when a respondent claims ownership of the good through the purchase action.

CAES 19- The impact of soil conservation techniques in Haiti. ¹C. M. Jolly, ²D. A. Shannon, ³M. Bannister, ⁴G. Fleurantin, ⁵J. Dale, ‘Zach” Lea, ⁶A. Bins, and ⁷P. Lindo. ¹Department of Agricultural Economics and Rural Sociology, Auburn University ²Departement of Agronomy, Auburn University., ³University of Florida, ⁴CIAT, HAP, Haiti; ⁵USAID, Afghanistan; ⁶Cahaba Safeguard Administrator (ILLC). ⁷Reclamation District of Greater Chicago, Il.

Soil erosion and environmental degradation are serious problems facing food security in Haiti. In 1999 the annual soil loss due to erosion was estimated at 36 million m³ tons. The government of Haiti has been aware of these deteriorating conditions and has sought international assistance to reduce these problems. In 1993, the United States Agency for International Development implemented a soil conservation project and millions of dollars were spent on the encouragement of adoption of soil conservation measures, yet the problem of soil degradation is still menacing food security in Haiti. Hence the need to evaluate the impact of soil conservation project in Haiti is important. A survey of 951 farmers who adopted soil conservation techniques in Haiti was conducted. The survey participants were composed of 83.6% males and 16.2% females. About 53.3% were illiterate; 42.9 and 4.0% received up to eight years schooling and primary education only, respectively. The age group range included 8.5% who were younger than 30; 30.8% who were between 30 and 45 years old; 32.6% who were between 45 and 60; and 28.1% who were more than 60 years old. The results showed that the soil conservation techniques adopted by farmers were rock walls, contour hedgerows, gully plugs, contour canals and crop bands. Multivariate logistic models indicated that if the soil conservation technique was leguminous hedgerows, the farmer was 0.8% less likely to encounter average to severe erosion than if the any other conservation technique was used. If the conservation technique was a crop band the farmer was 0.7% less likely to declare having average to severe erosion than if the conservation technique was a live hedge. The slope affected the degree of soil erosion. If the slope was estimated as less than 20 degrees, the farmer was 0.9% times less likely to declare that he/she encountered average or severe erosion. There was no significant difference in income among those who adopted the various soil conservation techniques. The income of farmers depended on the combination of crops produced and the size of the area cultivated. Most farmers were satisfied with the soil conservation techniques adopted; they were aware of the benefits of soil conservation techniques.

CAES 20- Potential impact of trade liberalization and trade-related policies on fisheries and measures required for their sustainable development in the CARIFORUM/CARICOM region. L. B. Rankine and G. Seepersad. The University of the West Indies, St Augustine, Trinidad and Tobago.

This paper reviews selected trade policy and other regulatory issues emerging at the global level, including specific market entry requirements and the issue of incentives, support, subsidies and the WTO. An examination of the Region’s fisheries infrastructure including landing sites, refrigeration facilities, health and food safety, as well as issues relating to sustainability and export of fishery products, is then presented. Proposals are also made towards development of a sustainable fisheries sector in the Region.

CAES 21- Building bridge between agriculture and tourism in US Virgin Islands. H. Solomon. University of the Virgin Islands, St. Thomas, USVI.

The US Virgin Islands are composed of the three small islands of St. Thomas, St. Croix and St. John. Each island possesses different potentials to foster agricultural and tourist development in the territory. St. John and St. Thomas have comparative advantage for tourism and very little for agriculture, but huge potential as a market for fresh food for the territory, whereas St. Croix has the greatest potential for agricultural production. However, there is lack of connection between agricultural and the tourist industry. As a result, the territory produces very little local food; virtually all the food is imported. St. Croix has the deep rich soil and flat topography suitable for many agricultural enterprises. This fact has existed ever since Europeans settled the island. It was the breadbasket of the three islands. Many profitable agricultural activities have been centered on St. Croix and many Europeans made great wealth from the rich soil and free slave labor by growing sugar and cotton. After the abolition of slavery, like all other plantation economies in the other Caribbean and North American region, these slave labor-dependent agricultural enterprises declined and died. No other viable agricultural system has replaced the historic crops, sugar and cotton, throughout the East Caribbean with the exception of small family farms of banana production in the Windward Islands. Despite impressive research on various fruits and vegetables, and animal breeding programs, including integrated aqua culture and vegetable experimental plots where fresh water fish and vegetables are produced year round with limited water supply, few of these agricultural alternatives have been adopted by the residents. The paper will identify the various problems related to agricultural production in the territory and make suggestions for policy makers to bridge the gap between agriculture and tourism to realize the potential of an integrated economic development in the territory.

CAES 22- Assessing the degree of food insecurity in the Dominican Republic: A pilot study. M. Bezuneh & Z. Yiheyis¹and P. J. Del Rosario². ¹Department of Economics, Clark Atlanta University, Atlanta, USA, ²Instituto Dominicano de Investigaciones Agropecuarias y Forestales(IDIAF).

In spite of the long period of economic growth and relatively low unemployment that characterized the Americas over the previous decade, food insufficiency and hunger continue to affect the majority of the population in Latin America and the Caribbean. As food insufficiency poses long-lasting challenge to nutrition, health and social policy, researchers both at public and private institutions have recently exhibited renewed and growing interest in measurement of food insufficiency at the household and individual levels. Most of the recent research on the subject uses food insecurity as a core indicator of the deprivation of basic food needs. The concept of food insecurity at the household and individual levels was an area of extensive research in the late 1980s by individual researchers and public agencies. This work culminated in the development of the US Food Security Survey Module (FSSM), which is now the standard methodology of determining household food security status. One of the purposes of this study is to adopt and translate the U.S. Food Security Survey Module in the context of a less developed economy, thereby assessing the prevalence of food insecurity and hunger. The module was administered as a pilot in a household survey of 110 low-income families in the Dominican Republic. This study found that 93% of the respondents were food-insecure, some more so than others, and the increasing percentage of food deprivation was considered. A relatively small proportion of the food-insecure (20%) reported food insecurity without hunger. Households which experienced hunger —moderate and severe— represented 74% of the entire sample and 80% of the food-insecure group. Among those who were insecure with hunger, 59% faced severe hunger. Child hunger was reported by 89% of households with children. Only seven percent of the households were found to be food-secure, with no or minimal perception and experience of food hardship during the reference period. A comparison of the food security status of households, on the basis of selected attributes on which survey data were available reveals differences in the prevalence and degree of food insecurity among various groups of households.

Keywords: Food Security Survey Model, Food insecurity, Survey, Low income families

CAES 23- Potential of agricultural development to increase rural employment. C. A. Pemberton¹and M. A. Mgonja². ¹University of the West Indies, St Augustine, Trinidad and Tobago, ²ICRISAT, Nairobi, Kenya.

The paper determined the potential of increased agricultural output to improve rural development by increasing rural employment in the Caribbean and Sub-Saharan Africa (SSA). The major problems facing agricultural development in the Caribbean and SSA are exogenous macro-economic forces as well as natural perils and weak export markets, all of which constraints increases in agricultural output. An analytical approach was developed to determine the potential increase in agricultural labor employment in response to simulated increases in agricultural output. The empirical analysis included the estimation of an aggregate production function for Caribbean agriculture. The results suggested that even a 4% annual increase in agricultural output has the potential for increasing agricultural employment by over 6% per annum, even with annual technical progress of 1.5% in the case of SSA and 2% in the case of the Caribbean. The paper concludes that there is definite potential for expanding rural employment through expansion of agricultural output, provided there is not the continued substitution of labor by apparently more inefficient capital input such as machinery.

CAES 24- A model for technology generation. M. Wilson. Caribbean Agricultural Research and Development Institute (CARDI).

It is suggested that effective technology generation is by extension, technology effectively transferred. Earlier rationalisations for the institutionalising of technology generation in the Caribbean appeared founded upon the assumption that what was chiefly necessary for industries in the agricultural sector to become viable (and consequently for entrepreneurial incomes to escalate) was an increase in farm firm productivity. The process between primary production and income generation reflected a mosaic of functionally related but uncoordinated components including marketing, processing, field/laboratory research, education/training. Much has since passed and new visions accompanied by the realities of the interconnectedness are in vogue. Unanswered and unimplemented, however, is the level and intensity of the focused coordination needed to guide the selective process that must essentially precede effective technology generation. It is argued that in order to generate effective technology the research institute must position itself to link strategically the players and processes that report the demand for technology and influence the appropriateness and timeliness of its delivery. Within the above context, this paper proposes that the principal tasks of the research institute are as follows: to initiate as well as promote the development of added value products and to intimately trace their corresponding linkage back to their lowest wrung; to ascertain/define therefrom the demand for a specified technology or range of technology products and services; to employ the resources necessary to generate the technology demanded through appropriate research processes; to engage, execute and/or coordinate those processes with the target community, the resources required for securing its effective adoption; and to monitor and evaluate the impact of the adoption process on enhancing technology generation and innovativeness.

CAES 25- The impact of the Central American Free Trade Agreement (CAFTA) on Central American and Caribbean economies. P. Gregorowicz and C. Ligeon. School of Business at Auburn University, Montgomery, AL.

Standard economic theory argues that Open Economies should grow faster than Closed Economies because of effects of trade and investment flows based on principles of comparative advantage. The significant positive effect on income growth associated with trade liberalization in Mexico, China and East Europe also supports this view. Trade and investment flows should provide significant incentives to the reallocation of resources to more efficient uses resulting in faster growth of per capita GDP over time. This paper investigates the likely impact of CAFTA on the Central American and Caribbean economies. This treaty makes permanent the trade benefits from earlier bi-lateral trade agreements referred to as the Caribbean Basin Initiatives (CBI) which were implemented in the 1980s. These arrangements made 80% of the regions exports to the U.S. duty free and stimulated FDI and GDP growth in the region. The data indicates that FDI to the Central American and Caribbean nations rose significantly in the 1990s after two decades of relatively poor performance. One of the possible effect’s of CAFTA is that this regions share of the expanding world FDI would be maintained and possibly improved by making the region more attractive to foreign investors. This outcome would stimulate per capita GDP growth in this region. In addition, this paper investigates the impact of this trade agreement on the structure of output and employment by using Mexico and its NAFTA experience as a model. The effect of NAFTA on the growth in Mexico will be investigated as well as its impact on the structure of output and employment. The paper hypothesizes that CAFTA nations should experience similar patterns in the structure of output with the reallocation of labor resources out of agriculture into industry and service sectors.

Agronomy and Natural Resources (ANR)

ANR 1P- Prediction sediment and nutrient loads in tropical watersheds in Puerto Rico. E. Martínez¹, L. R. Pérez², D. Sotomayor¹, and G. Martínez¹. ¹Department of Agronomy and Soils, ²Department of Agricultural Engineering and Biosystems, University of Puerto Rico, Mayagüez Campus.

Water is essential to support life. Sediment and nutrient concentrations in streams are precursors or indicators of stream impairment. According to recent estimates, about 40% of the monitored national water supplies do not meet quality standards to support designated uses. A similar situation is observed in Puerto Rico. The 2002 water quality inventory of Puerto Rico reports that 67% of the monitored river miles were impaired. For this study water quality parameters were sampled during the 2004-2005 water year in four sub watersheds (Río Limón, Río Grande de Arecibo, Río Caonillas and Río Jauca) of the Río Grande de Arecibo watershed, located in the central part of Puerto Rico. The objective of this thesis research was to determine sediment and nutrient loads and to propose mathematical relationships to relate sediment and nutrient loads to physiographic and orographic properties of the sub watersheds. Sampled variables include pH, temperature, conductivity, salinity, water velocity, total suspended sediment, chlorophyll a, total Kjeldahl nitrogen (TKN), total phosphorus (TP) and dissolved phosphorus (DP). Sediment loads and yields from storm events ranged from 3,352.08 tons/event and 35.77 ton/km² for Río Limon to 33.06 tons/event and 1.87 ton/km² for Río Jauca. Nutrient concentrations range from 6.49 to 1.11 mg/L of TKN, 1.82 to 0.05 mg/L of TP; and 0.24 to 0.05 mg/L of DP. Median values of Chlorophyll a, ranged from 6.48 to 3.36 mg/L. Mathematical expressions are presented and used to predict sediment and nutrient loads from these watersheds.

ANR 2P- Bacteria associated to the rhizosphere of plants growing on eroded soils. J.A. Chavarría¹, R. Ramos², and L. Silva². ¹Department of Crop Protection and ²Department of Agronomy and Soils, University of Puerto Rico - Mayagüez Campus.

One of the greatest environmental problems in the tropics and subtropics is the accelerated level of soil losses due to erosion. A primary strategy to reduce soil erosion on denuded lands consists of providing coverage with plant species. This strategy consists of the use of plants capable of growth on eroded soils to improve the physical, chemical, and microbiological properties of the soil, thus restoring soil fertility to a level adequate to sustain germplasm adaptation and growth. Rhizosphere samples from Desmodium heterophyllum, Brachiaria decumbens, Peltophorum inerme and an eroded soil used as control were taken during three growing seasons. Bacteria populations were estimated through the isolation of 20 colonies per treatment on TSA 5%. Bacteria strains were identified with fatty acid methyl esters (FAMEs). Higher bacteria populations were associated with B. decumbens and D. heterophyllum. The predominant bacteria genus was Bacillus spp.; among those, B. cereus, B. megaterium, and B. pumilus were the species with most frequency. Plant species substantially increased bacteria levels and soil diversity. Plant species influenced the amount and the diversity of bacteria associated with the rhizosphere. Results from this study may serve to understand the effect of selected plant species in improving microbe populations on marginal soils.

ANR 3P Evaluation of minimum tillage technologies for the establishment of Brachiaria decumbens on the north western costal plains of Puerto Rico. R. Ramos, D. Cianzio, A. Vázquez, and L. Añeses. University of Puerto Rico, Agricultural Experiment Station.

Rapid grassland deterioration is one of the greatest ecological problems of many countries in the world. At present few beef cattlemen use improved rangelands and the high cost involved in establishing pastures by stem sections discourages cattlemen from improving pastures. Three minimum soil tillage techniques for establishment of Brachiaria decumbens pastures in Puerto Rico were evaluated. The minimum tillage establishment technique using one superficial harrow disc pass, without any previous glyphosate application (treatment 2), showed an extremely poor pasture germination and coverage. This finding showed that the application of minimum tillage techniques without the previous use of glyphosate produced an increment of weed population above that of grasses. The treatments of conventional planting without glyfosate (treatment 1), non tillage with previous application of glyphosate (treatment 3), and one superficial harrow disc with previous application of glyphosate (treatment 4) showed no significant (p<0.05) differences in soil coverture and plants/m² four months after establishment. Similarly, the average available dry matter yield (ADMY) during the three consecutive grazings after establishment showed no significant (p<0.05) differences among the three above mentioned treatments. From the agronomic perspective the three treatments were similar, and minimum tillage technologies were not an improvement over the conventional planting system. In terms of the projected costs for pasture establishment associated with the three treatments, no significant differences (p<0.05) were observed among the three. Total cost for treatment 1 was $577/ha, followed by that of treatment 3 with $478/ha, and by treatment 4 with $436/ha.

ANR 4P Determination of nutrient loads for the Río Grande de Arecibo watershed. A. A. Bernal, L. R. Pérez, and D. Sotomayor. Department of Agronomy and Soils, Department of Agricultural Engineering and Biosystems. University of Puerto Rico – Mayagüez Campus.

Protection of the surface waters is critical for the sustainability of life and economic development of all countries. The nutrient over-enrichment of surface waters promotes eutrophication and deterioration of water resources, resulting in low dissolved oxygen (DO) in the water column modifying biodiversity and the aesthetic value of lakes and reservoirs. This project is conducted in the Río Grande de Arecibo (RGA) watershed and Lake Dos Bocas in the north central region of Puerto Rico. Since 2000 Lake Dos Bocas has been the potable water supply for over one million people in the north corridor, including the San Juan metropolitan area. The objective of this project is to link a water quality model of the Dos Bocas lake with a watershed based hydrologic-hydraulic model in order to predict DO fluctuations as a result of land use practices in the upper watershed of the RGA. A discussion of existing models and data input/output requirements is presented as a preliminary outcome of this study.

ANR 5P Sorption and transformation of pesticides in carbonatic soils from Florida and Puerto Rico. P. Nkedi, J. A. Dumas, G. N. Kasozi, and S. M. Soler. University of Florida.

Sorption and transformation are major processes that affect the fate and transport of pesticides in the environment. For the carbonatic soils found in South Florida and Puerto Rico pesticide sorption and degradation rate coefficients are not available in the literature. In our research project we have so far characterized sorption of four pesticides (Atrazine, Ametryn, Carbaryl, and Diuron) in 10 carbonatic soils and nine associated non-carbonatic soils from Florida and Puerto Rico. The soil organic matter content (OM%) was found to be correlated with soil carbon content (OC%) with a conversion factor of 1.822 for carbonatic soils. The conversion factor of 1.822 was not significantly different from the factor of 1.724 generally used in the literature for non-carbonatic soils. The sorption coefficient (KD) was normalized to soil OC to yield KOC values. The KOC values obtained in carbonatic soils for Atrazine, Ametryn, Carbaryl, and Diuron were about one third of KOC values for non-carbonatic soils. This finding implies that OC in carbonatic soil is not as effective as OC from non-carbonatic soils to adsorb the four pesticides, which have contrasting chemical classes (s-triazine, carbamate, and substituted urea). Preliminary data for strongly hydrophobic organic chemicals (SHOCs) such as Dieldrin and Endosulfan (with low aqueous solubility) sorption on container walls (glass, plastic, and Teflon) gives erroneous sorption coefficients. For example, 76% of Endosulfan in water was adsorbed on Teflon centrifuge tubes. We are therefore developing a batch sorption technique based on the Solvophobic theory that will eliminate sorption on container walls. The sorption of SHOCs will be determined in mixed solvents and the aqueous KOC will be calculated by using the Solvophobic model. Preliminary transformation data have been collected for Atrazine in five soils. There is no significant difference in half life (t1/2) values between carbonatic and non-carbonatic soils. The data base obtained in this study will be useful to government regulatory agencies and modelers of pesticide fate and transport in the environment.

Keywords: Pesticides, Carbonatic soils, Sorption, Transformation, Organic carbon

ANR 6P- Characterization of soil in the Puerto Rico coffee agroecosystem. L. Cruz and E. C. Schroder. Department of Agronomy and Soils, University of Puerto Rico - Mayagüez Campus.

The coffee industry in Puerto Rico is an important industry in the mountain region. The region is located in the central part of the island and includes 20 municipalities. The number of coffee producers now reaches 10,000, with a total of 25,000 people economically involved in cultivation and harvest. Coffee is cultivated on acid, highly erodable soils which are steeply sloped. Understanding in detail the characteristics and spatial distribution of the soils in the coffee region is important to the development of appropriate management plans. The coffee region encompasses an area of 193,750 ha, 58.3% of which are eroded soils. The geology is dominated by Cretaceous volcanic rocks and plutonic rocks. There are sixty-eight soil series 30,934 ha of which have between 20 to 40% slope, and 120,613 ha have greater than 40% slope. Most upland is dominated by Oxisols and Ultisols. Common features of the upland soil series in the coffee region include high clay, up to 65%, and acid conditions (pH from 3 to 5). The Inceptisols tend to be coarser textured on eroded landscapes than their contiguous upland counterparts. Soil conservation is a requisite for maintaining coffee production without the use of expensive inputs.

ANR 7P - Citrate exudation by bean cultivars, a potential mechanism to overcome Al³⁺ toxicity. M. A. Muñoz, J. S. Beaver, F. R. Román, and S. Ortega. Department of Agronomy and Soils. University of Puerto Rico, Agricultural Experiment Station.

The secretion of organic acids by plant roots can be an indication of their capacity to tolerate acid soil conditions and toxic levels of exchangeable Al³⁺. Organic acids such as citric, malic and oxalic acids are capable of complexing Al³⁺, reducing its toxicity to plant roots. A growth chamber study was conducted to determine the effect of three Al³⁺ concentrations (0, 25 and 50 µM) on root development of bean cultivars and on the capacity of the cultivars to secrete organic acids. The bean cultivars Morales, Salagnac 90A, Batt 477, Vax 1 and Arroyo Loro were used in the study. The bean seedlings were grown in nutrient solutions and were exposed to the Al³⁺ solution concentrations for 48 hours. Organic acid exudation by Morales variety was measured by using an anion exchange chromatograph Dionex IC 20, equipped with an EG 40 Eluent Generator. The analytical column was Dionex Column AS11-HC 4 x 250 mm (P#052960), coupled to a Guard Column AG11-HC 4 x 50 mm (P#052962). The presence of citrate and oxalate was detected in the solution when the seedlings were exposed to 25 and 50 µM Al³⁺ solutions, but that was not the case for the 0 µM treatment. The citrate peak was observed around 33 minutes retention time. The citrate conductivity peak was more intense at the higher aluminum concentration. The intensity of conductivity, the peak when Morales bean seedlings were exposed to 25 µM Al³⁺ in solution, was 2.25 µS and increased to 3.32 µS when exposed to 50 µM Al³⁺. This finding indicates that larger amounts of citrate are produced by bean roots as the concentration of Al³⁺ in solution is increased. Average root length between Al³⁺ treatments ranged from 2.0 to 2.6 cm and number of secondary roots ranged from 16 to 19.

Animal Sciences (ANSC)

ANSC 1P- Concentrate feeding effects on goats’ reproductive performance. A. Acero, A. Rodríguez and E. Valencia. Animal Industry Department, Agronomy and Soils Department, University of Puerto Rico - Mayagüez Campus.

Goat (Capra hircus) nannies with energy deficiencies and poor body condition often have low conception rates, low twinning rate, and kids with low birth and weaning weights. Flushing consists of an increase in the energy level offered to nannies prior of the introduction of the buck pre and post 21 days. By flushing, ovulation and implantation of the fetuses in the uterus are improved. It is important to determine what energy levels are necessary for good reproductive results. The objective of this study was to assess two concentrate level (CL) feeding effects on body condition scores (BCS), body weight, kidding, birth and weaning weight, and weight gain of kids. Treatments were a high CL (600 g d of mixed grain per nanny) and a low CL (300 g d of mixed grain per nanny) in a completely randomized design. Six nannies were assigned to each treatment. Flushing started 21 d prior to the introduction of the buck and continued for 21 d after. Thereafter, all nannies were feed a low CL until parturition. Nannies were weighed bi-monthly and BC scores taken monthly. There were no effect of CL (P>0.05) on body weight, BCS, and kid numbers. But kid birth weight was lower (2.5 kg/kid) with the high CL than with the low CL (3.27 kg/kid), respectively. This difference was a result of more twinning on the high CL. There was also no effect of CL on weaning weights (8.2 vs. 7.8 kg) and weight gains (860 g/wk vs. 727g/wk) with the high and low CL, respectively. This study showed that CL greater than 300 g d of mixed grain per nanny prior to and after the mating season did not improve reproductive performance in meat goat. However, flushing in nannies with low BCS (<3) needs to be evaluated.

ANSC 2P- FAMACHA: A practical method to identify anemia in small ruminants and minimize anthelmintic use in the Caribbean Basin. E. Valencia¹, A. A. Rodríguez² and M. E. Pagán². ¹Agronomy and Soils Department, ²Animal Industry Department, University of Puerto Rico – Mayagüez Campus.

A major challenge facing the small ruminant industry in the southeastern US and eastern Caribbean Islands is the effective control of internal parasites such as Haemonchus contortus (Barber Pole Worms; BPW). A larval development assay (DrenchRite^®) on pooled fecal samples collected from both sheep and goats in different agro-ecological zones of Puerto Rico in 2005 suggested resistance against most commercial dewormers. Clinical laboratory methods available to measure BPW infestation include the fecal egg count (FEC) and the packed cell volume (microhematocrit; PCV) to measure anemia. Recently, a chart called FAMACHA^® developed in South Africa enables clinical identification of anemic sheep and goats. This study validated the FAMACHA^® chart on sheep (Lajas Valley) and goats (Finca Alzamora) by examining the ocular mucous membrane and eye scoring (ES) on a scale of 1-5, and taking blood via jugular venipuncture for PCV, and fecal samples to determine FEC from June to October 2004. To further validate the FAMACHA^® card, a second experiment was conducted on small ruminant farms (two each) in the dry (Cabo Rojo), dry/wet (Moca) and humid (Utuado and Orocovis) regions of Puerto Rico. In Experiment 1, correlations between eye scores and PCV, and PCV and FEC were high (P<0.05) and varied during sample period because of drenching. In Experiment 2, FAMACHA^® scores were intermediate (2.9 to 3.5, slightly anemic) and PCV ranged from 23 to 25% in all regions. In the dry region, FEC was higher (P<0.05) than in the humid, but was not different from that of the dry/wet region. Correlations between eye scores, PCV, and FEC were also high (P<0.05), although the level of association between eye score and PCV was better. The present finding suggests that FAMACHA^® is an adequate tool for detecting anemia in sheep and goats. Selective deworming using this simple and farmer-friendly guide could avoid further development of anthelmintic resistance in small ruminants with perhaps a subsequent reduction of cost associated with the treatment of infected animals.

ANSC 3P- Evaluación del efecto de la inclusión de cuatro diferentes niveles de grasa en dietas de cabritos (Capra hircus) de engorde. Y. H. Pérez, C. M. De Jesús y R. A. Vásquez. Instituto Superior de Agricultura de la República Dominicana.

El contenido de energía en las raciones, al igual que el de proteína, es un factor limitante en las raciones de rumiantes, donde el bajo contenido de energía en raciones de cabras induce a pérdida en el peso, tamaño, fertilidad y producción e inmunosupresión. La adición de grasas a la dieta incrementa la densidad de energía; la inclusión de grasa en 5 a 6% del total de la MS no afecta el consumo ni tampoco la utilización de los nutrientes en rumiantes. Con el objetivo de evaluar el rendimiento de cabritos alimentados con dietas que contenían cuatro niveles (0, 4, 8 y 12%) de grasa añadida, 64 cabritos (Capra hircus) mestizos de las razas Boer, Nubia, Alpina y Criolla se agruparon en tres, cuatro y seis animales por corral en forma aleatoria. Los cabritos se sometieron al mismo sistema de manejo, con variantes en la ración alimenticia, que consistió en una ración balanceada sin grasa añadida (0%), y con 4%, 8% y 12% de grasa con forraje controlado. Los forrajes proporcionados fueron King Grass (Pennisetun purpureum), hierba guinea (Panicum maximun), batata forrajera (Ipomoea batatas L.), Morera (Morus alba). La fase de adaptación fue 14 días. Las variables evaluadas fueron consumo de alimento, ganancia de peso, eficiencia alimenticia, relación beneficio/costo. Los cabritos incrementaron el consumo de manera significativa (P>0.05) a medida que aumentaban de tamaño. Al inicio los cabritos prefirieron las raciones con 4% de grasa con relación a las de mayor inclusión de grasa. Sin embargo, a partir de la novena semana se incrementó el consumo de las raciones con mayor contenido de grasa (8 y 12%). La mayor ganancia diaria promedio de 150 g/d se obtuvo en el tratamiento de 8% de grasa añadida, aunque al inicio del estudio las máximas ganancias de peso corporal (170 g/d) se obtuvieron en cabritos alimentados con 0% de grasa. La relación beneficio-costo más alta se obtuvo en el tratamiento con 8% de grasa, aunque en todos se reporto pérdidas. Se concluye que la adición de grasa en el engorde de cabritos no afecta adversamente el consumo ni la respuesta animal hasta un 4% de grasa en la dieta de engorde de cabritos.

Crop Protection (CP)

CP 1P- Use of a beneficial nematode against pest mole crickets in Puerto Rico. N. E. Vicente, J. H. Frank, and N. C. Leppla. University of Puerto Rico, Agricultural Experiment Station, University of Florida.

A beneficial nematode, Steinernema scapterisci (Rhabditida: Steinernematidae), has been researched at the University of Florida and is now marketed as a biopesticide. Its primary target is the mole cricket Scapteriscus vicinus (Orthoptera: Gryllotalpidae), which has been a pest in Florida for about 100 years. The nematode survives so well in Florida’s sandy, low-organic soils that it serves as a classical biological control agent to provide permanent suppression of pest mole cricket populations in places to which it has spread. In Puerto Rico and islands of the Lesser Antilles, the primary mole cricket pest is Scapteriscus didactylus and there is a much wider range of soils. Our research evaluates the use of the nematode to control Scapteriscus didactylus. An in-vitro trial in sterilized sand showed 100% survival of controls, but up to 100% mortality of mole crickets within 168 h dependent upon number of nematodes applied (dose or ‘rate’). In-vitro survival of nematodes was significantly poorer in non-sterilized soils than in sterilized soils. Field tests of survival of nematode populations showed establishment and survival up to eight months in a heavy clay loam with mole crickets, but no establishment in a highly organic sandy soil with mole crickets.

CP 2P- Evaluation of various insecticides in controlling melon thrips, Thrips palmi Karny. D. Seal and C. Sabines. University of Florida.

The melon thrips, Thrips palmi Karny, is an economic pest of various vegetable crops in south Florida. This pest attacks all the above-ground parts of host crops. Pupation of this insect takes place in soil. Thus it avoids insecticide spray and reinfests crops after emergence. Sintor is an effective insecticide that provides significant control of melon thrips. Dependance on one insecticide may enhance resistance in insect. To avoid repeated use of same insecticide, further studies have been undertaken to improve the melon thrips management program. In the present study, effect of some insecticides alone or in combination with surfectants will be evaluated against melon thrips.

CP 3P- First report of powdery mildew of onion caused by Leveillula taurica (Lev.) Arn. in Puerto Rico. M. Feliciano and L. I. Rivera Vargas. Department of Crop Protection, University of Puerto Rico, Agricultural Experiment Station.

From January to March 2006, powdery mildew was observed in onion (Allium cepa L.) foliage (cv. Mercedes) grown at the University of Puerto Rico-Agricultural Experiment Station in Juana Diaz, P.R. Climatic conditions prevailing during this period were low precipitation, temperatures ranging from 20 to 31 °C, and low relative humidity. First symptoms appeared 75 days after sowing. Leaves showed white to gray powdery patches that coalesce affecting the entire area. Symptoms were observed on young and mature leaves. A visual scale was used to estimate disease severity in the field ranging from 1 to 5 (1 = 0%, 2 = 1-25%, 3 = 26-50%, 4 = 51-75% and 5 = 75-100% of plants affected). Over all, plant damage observed in the field ranged from 26 to 50%. Leaf samples were collected and examined under the microscope. Powdery growth on the leaf consisted entirely of conidia and conidiophores singly or in groups (156 x 10 µm), that emerged through the stomata. Two different types of conidia were observed, a primary lanceolate conidia (48 x 10 µm) and secondary cylindrical conidia (52 x 15 µm). On the basis of morphological characteristics (i.e., conidiophore and conidia) the pathogenic fungus was identified as Leveillula taurica (Lev.) (teleomorph of Oidiopsis sicula). The sexual stage of the fungus was never observed in the field. To our knowledge, this is the first report of powdery mildew of onion caused by L. taurica in Puerto Rico.

CP 4P- Evaluation of fungicides for control of rust and powdery mildew on snap beans in Florida. R. N. Raid, R. T. Nagata, and K. Pernezny. University of Florida, IFAS.

Common bean rust (Uromyces appendiculatus) and powdery mildew (Erysiphe polygoni) are important diseases in Florida snap beans. Two fungicide trials were conducted to evaluate fungicides for control of rust and powdery mildew. Fungicides evaluated included azoxystrobin (Amistar), myclobutanil (Nova), chlorothalonil (Bravo Ultrex), sulfur (Sulfur WP), and an azoxystrobin/propiconazole pre-mix (Quilt). Experimental units were two rows by eight meters and these were arranged in a randomized complete block design with four replications. Two nonsprayed guard rows separated all treatments and served as inoculum spreader rows. Diseases were rated on a 0 to 10 scale, with 0 representing no visible disease and 10 representing the entire canopy being infected. Disease pressure from rust was severe, with severities of greater than 40% occurring on leaflets in non-sprayed checks. Heavily rusted trifoliolates frequently dehisced prior to bean maturation. Powdery mildew also built up to substantial levels, affecting greater than 50% of the plant canopy in non-sprayed checks. All fungicides provided for significant reductions in disease severity for both diseases. Sulfur provided excellent control of powdery mildew but not against rust. Bravo provided control of both diseases but its levels were significantly lower than levels afforded by Nova and Amistar. Quilt provided near total control of both diseases. Plant biomass and marketable yield were significantly impacted by the diseases of interest. In comparing yields in the check with those in the best treatments, bean yields were reduced by an average of 57%. Yields obtained from treatment with a sterol inhibitor were not significantly different from those obtained with a strobilurin; however, both produced yields significantly greater than those obtained with a broad-spectrum protectant.

CP 5P- Screen cages protect transplants against the main viruses infecting vegetable crops in the US Virgin Islands. R. A. Arancibia. University of the Virgin Islands.

The high incidence of viral diseases is a major constraint to vegetable crop production in the US Virgin Islands (USVI). A survey of viral diseases infecting peppers and cucurbits was conducted in St. Croix during summer 2005 and spring 2006. In addition, Puerto Rican sweet pepper (PRSP) and summer squash seedlings were grown in a cage covered with a 80 mesh net to evaluate the level of protection against insect-vectored viral diseases in the USVI. Tobacco Etch Virus (TEV) and Pepper Mottle Virus (PeMoV) were detected in peppers. Papaya Ring Spot Virus (PRSV) and Zucchini Yellow Mosaic Virus (ZYMV) were detected in summer squash, zucchini, and calabaza, and an additional unidentified potyvirus was detected in cucumber. In the protection study, TEV and PRSV were found in unprotected PRSP (11%) and summer squash (3%) transplants, respectively. In contrast, no virus infections were detected in protected seedlings. Infected PRSP transplants were stunted and bore little or no fruit in the field. Similarly, early infections of PRSV in summer squash cut short the production period and produced mainly symptomatic unmarketable fruits. Use of protected structures against virus-vectoring insects is an efficient and environmentally friendly strategy to reduce the incidence of viruses during transplant production.

CP 6P- A survey of root-feeding pests on tropical fruit trees in Puerto Rico. D. Jenkins and R. Goenaga. USDA - ARS Tropical Agriculture Research Station (TARS).

From March 2003 to December 2005 traps were used to monitor the abundance of Diaprepes abbreviatus and Phyllophaga spp. adults emerging from the soil at the base of several exotic tropical fruit trees (Pouteria sapota, Manilkara zapota, Litchi chinensis, and Nephelium lappaceum) at three different sites on the island of Puerto Rico (Isabela, Adjuntas, and Corozal). Although there were no consistent differences in susceptibility among the varieties within any of the crop species, there were robustly significant differences between the number of both beetle species at the different sites and also with regard to “preferences” of both beetles for certain crop species. Isabela had many more of both beetles than either Corozal or Adjuntas. At Isabela, Phyllophaga spp. were significantly more abundant in mamey sapote (Pouteria sapota) than in the other crops, although it was also abundant in sapodilla (Manilkara zapota). At Isabela, D. abbreviatus was significantly more abundant in litchi (Litchi chinensis) than in the other crops. Phyllophaga spp. were more abundant than D. abbreviatus at Isabela. Both D. abbreviatus and the Phyllophaga spp. emerged throughout the rainy season (April to October) with peaks of emergence at the beginning and end of the rainy season. These results are discussed in light of potential management programs exploiting unique aspects of these pests’ life histories.

CP 7P- Hosts of Anastrepha spp. in Puerto Rico. D. Jenkins and R. Goenaga. USDA - ARS Tropical Agriculture Research Station (TARS).

In this ongoing study, potential hosts of Anastrepha spp. were collected throughout the year and monitored for the emergence of fruit flies and their parasitoids. In addition, multi-lure traps baited with putrescine and ammonia acetate were used to monitor fruit fly population fluctuations at four locations on the Island. As expected, naturalized mango (Mangifera indica), Spondias mombin, and S. purpurea are important hosts for Anastrepha obliqua, but these fruits are available only in the summer. Terminalia catappa, available at various times throughout the year, was an important host for A. suspensa, although we occasionally reared A. obliqua from it. Psidium guajava, also available at various times throughout the year, was a host to both species of fruit flies, although A. suspensa was more commonly reared from this fruit. Other fruits that yielded fruit flies were carambola (Averrhoa carambola) and Syzygium malaccense (yielding almost entirely A. obliqua). Parasitoids (Utetes anastrephae) were reared from both species of fruit flies that had been in fruit of T. catappa, mango, an unidentified Syzygium sp., and P. guajava. Locations yielding parasitoids were Mayagüez (Tropical Agriculture Research Station, USDA-ARS), Adjuntas (UPR-Agricultural Experiment Station), and Corozal (UPR-Agricultural Experiment Station). Most parasitoids were reared from fruit flies collected during the summer months. The life history of both Anastrepha spp. is discussed in relation to their host phenologies.

CP 8P- Coconut lethal yellowing in Nevis. L. Paulraj and W. Myrie. Caribbean Agricultural Research and Development Institute (CARDI).

Sudden death of hundreds of coconut trees was noticed in Nevis. Investigations revealed that the trees were affected by lethal yellowing disease (LY) caused by a phytoplasma. The early symptoms are premature dropping of fruits; the flowers turn brown to black. The inflorescence tends to become dry and gnarled; at later stages the leaves turn yellow, desiccate, turn brown and hang from the tree. Final stage is death of the bud; the youngest unfolded leaf, the spear leaf, collapses and eventually the tree dies. Samples were taken from the young tissue below the meristem tip and PCR characterization of the samples taken confirms the presence of phytoplasma. A comprehensive control strategy is in place to protect from the ravaging disease and to save the landscape of the island. The disease is of quarantine important to the region and beyond, since it affects not only coconut palms, but also some 35 other species of palms.

CP 9P- Evaluación de variedades de tomate de mesa para Liriomyza sp., Bemisia sp., Myzus persicae, Trichoplusia ni y Helicoverpa zea. I. Cabrera, G. Fornaris, S. Martínez y A. Vélez. Universidad de Puerto Rico, Estación Experimental Agrícola.

Los insectos más frecuentes en tomate de mesa en Puerto Rico son Liriomyza sp., Bemisia sp., Myzus persicae, Trichoplusia ni o Pseudoplusia includens, Helicoverpa zea, Manduca sexta, Spodoptera frugiperda y Keiferia lycopersicella. El uso de insecticidas es el método de control más utilizado por los agricultores de tomate en el sur de Puerto Rico. El buscar métodos de control alternos fue el objetivo de estos ensayos. Durante dos años consecutivos (2003 y 2004) se evaluaron ocho variedades de tomate de mesa: Florida 91, Pik Ripe 461, Pik Ripe 747, Sunbean, BHN 543, Mountain fresh, STM 0227 y STM 0231. Los experimentos de campo se llevaron a cabo en los pueblos de Lajas y Juana Díaz en terrenos de la Estación Experimental Agrícola. Los muestreos para insectos se realizaron semanalmente. Se evaluaron sólo los insectos que estuvieron presentes durante los ensayos de campo: Liriomyza sp., Bemisia sp., M. persicae, T. ni y H. zea. El primer año en Lajas no hubo diferencias significativas entre las variedades para los insectos Liriomyza sp., Bemisia sp., Trichoplusia ni, Myzus persicae y H. zea. Sin embargo, ese mismo año, en Juana Díaz, la variedad Sunbean tuvo el menor número de Liriomyza sp. por hoja, la STM 0231 obtuvo el menor número de Bemisia sp. por trifolio y la variedad Pik Ripe 747 tuvo el mayor porcentaje de daño de fruta por H. zea. Durante el segundo año solo hubo diferencias significativas para Bemisia sp., siendo la variedad Pik Ripe 747 la que tuvo el menor número de moscas blancas. No se observó un patrón que indique que alguna de estas variedades pudiera tener tolerancia a los insectos evaluados. Se deben continuar evaluando variedades de tomate de mesa o continuar buscando otras alternativas de control.

Palabras Clave: Tomate, Insectos, Liriomyza, Bemisia, Myzus persicae, Trichoplusia, Helicoverpa zea

CP 10P- Development of a biological control program for the West Indies fruit fly Anastrepha obliqua (Maquart) in Puerto Rico. J. Pérez, Y. Gil, R. Medina, D. Roldan, T. Holler, and A. Roda. USDA-APHIS-PPQ.

The West Indies fruit fly, Anastrepha obliqua Macquart (Diptera: Tephritidae) is a major pest of mangoes in most tropical countries. This pest also attacks 73 other species of fruit and has one of the broadest distributions of any pest tephritid. The costs of trapping, imposed quarantine surveillances, temperature treatments of fruit, bait sprays, fumigation, and environmental concerns about the use of methyl bromide necessitate the development of multiple management strategies. Biological control could reduce populations of this significant threat to US fruit production. In Mexico, the parasitoids Doryctobracon areolatus (Hymenoptera: Braconidae) and Utetes anastrephae have currently reduced West Indian fruit fly numbers from 40 to 70% in wild fruit. The parasitoids not only lower the probability of the pest spreading, but also increase the efficacy of other control measures such as bait sprays and SIT. In Puerto Rico several attempts have been made to introduce exotic parasitoids; however, none of these species are known to have established because of low release number, introduction to the wrong habitat, or use of species not likely to attack A. obliqua. Using the West Indian fruit fly as a model system, a collaboration staff of USDA APHIS PPQ, CPHST and USDA ARS personnel developed a protocol for the successful introduction and evaluation of a fruit fly biological control program. Surveys of fruiting phenology and abundance over the year were conducted to determine the optimal location to release the exotic parasitoid D. areolatus. Two release sites, Luquillo and Añasco both amenable to the introduction of D. areolatus establishment, were identified on the basis of the greatest A. obliqua host plant diversity and larvae populations most likely to support establishment of D. areolatus, and the presence of the native parasitoid, Utetes anastrephae. In Mexico, the two parasitoids co-exist; hence the factors favoring the existence of Utetes may also enhance the likelihood that D. areolatus will establish. The methods developed through the work in Puerto Rico could be used as part of an integrated pest management program for the suppression of A. obliqua in Puerto Rico and the Caribbean Basin.

CP 11P- Efecto de las cubiertas plásticas para el control de trípidos en pimiento de cocinar cubanelle. I. Cabrera, J. Funderburk y A. Vélez. Universidad de Puerto Rico, Estación Experimental Agrícola.

Se realizó una prueba de campo con pimiento de cocinar cubanelle para determinar la incidencia de trípidos en este cultivo. De los trípidos encontrados en las flores de pimiento de cocinar, el más abundante fue Thrips palmi (K). También se encontró a Frankliniella occidentales y F. fusca. En el campo se realizó una prueba con parcelas subdivididas, donde se utilizaron dos cubiertas plásticas al suelo, una aluminizada y otra negra, para observar la incidencia de trípidos en las flores de pimiento. También se evaluaron insecticidas tales como oxamilo 0.09 kg[AI]/ha, esfenvarelato 0.057 kg[AI]/ha, acephato 0.85 kg[AI]/ha, spinosad 0.075 kg[AI]/ha y un control. En el análisis estadístico realizado no se encontró diferencia entre las cubiertas plásticas utilizadas pero se encontraron diferencias significativas entre los insecticidas utilizados en algunos de los muestreos. Por ejemplo, cuando se usó oxamilo hubo un menor número de trípidos por hoja que cuando se usó esfenvarelato, acephato, spinosad y el control. Los resultados demostraron que el insecticida oxamilo disminuyó la población de trípidos por más semanas que el resto de los insecticidas. Este resultado requiere evaluaciones continuas para observar el patrón de comportamiento de las poblaciones de trípidos en el cultivo de pimiento cubanelle con el uso de estos insecticidas. Esta información podrá ayudar en un futuro a identificar la densidad poblacional de los trípidos en pimiento, además de identificar cuáles insecticidas pueden ser utilizados en un plan de manejo integrado.

CP 12P- Enfermedades prevalentes en la sandía en el área sur de Puerto Rico. C. Estévez, E. Rosa, G. Fornaris, R. Morales y W. Mercado. Universidad de Puerto Rico, Estación Experimental Agrícola.

En fincas del Municipio de Santa Isabel, P.R., se recolectaron muestras foliares y de raíces de plantas de sandía (Citrullus lanatus) “Royal Sweet” en diferentes estados de desarrollo del cultivo (15, 45 y 65 días del trasplante). A los 15 días del trasplante la incidencia de ‘damping-off’ causada por Pythium spp. y Rhizoctonia solani evaluada en tres bancos de 20 pies de largo fue de 1 a 3%. Las enfermedades foliares observadas a los 45 días del trasplante incluyeron manchas producidas por Alternaria spp. y Cercospora spp. diferenciadas por el tamaño de la lesión y el color. Cercospora spp. presentó lesiones redondas de color café con tonalidades gris en el centro y halo clorótico. Alternaria spp. presentó manchas irregulares de aspecto húmedo y tonalidad obscura de 1 a 3 cm de largo y el centro con tejido necrosado. A los 65 días luego del trasplante la severidad de Cercospora spp. aumentó a aproximadamente 50%. Síntomas de la enfermedad conocida como “Gummy stem blight” o tizón gomoso del tallo, producida por Didymella bryoniae, fueron evidentes a los 45 días del trasplante, con lesiones largas cafés a lo largo del tallo y exudado color ámbar en la base del tallo. A 65 días del trasplante las hojas mostraron clorosis y bordes cafés; de los tallos se aisló, en agar de papa y dextrosa acidulado (APDA), el estado asexual del hongo que produce esta enfermedad, Phoma spp. Las hojas se tornaron quebradizas con apariencia seca. En la época de llenado de fruto se presentó un marchitamiento progresivo de las plantas sin aparente daño vascular y en un período de siete días las plantas se secaron y murieron. La incidencia del marchitamiento súbito o “vine decline” fue del 100% en tres fincas. Verticillium sp. se obtuvo a partir de cortes de tejido de raíz y asilamientos en APDA. En pruebas de patogenicidad para Pythium spp. y R. solani se presentaron síntomas de marchitez en plántulas de tres a cinco días después de la inoculación. Se reaislaron los patógenos en APDA. Para los otros hongos se están realizando las pruebas de patogenicidad. Las enfermedades más destructivas de la sandía en el área sur de la isla aparentan ser el “tizón gomoso del tallo” causado por el hongo D. bryoniae y el “marchitamiento súbito de la sandía”, causado por un complejo de patógenos.

Palabras Clave: Enfermedades de sandía, Citrullus lanatus, Marchitamiento súbito de la sandía

CP 13P- Enfermedades más comunes de la flor de pascua en Puerto Rico. C. Estévez, M. Zapata, W. Almodóvar y R. Morales. Universidad de Puerto Rico, Estación Experimental Agrícola.

La producción de la flor de pascua o ponsetia (Euphorbia pulcherrima) se vio afectada en el año 2005 por varias enfermedades fungosas y bacterianas en Aibonito, Puerto Rico. Las condiciones de clima nublado, húmedo y fresco prevalecientes en la zona fueron apropiadas para la presencia de varias enfermedades. La podredumbre gris, moho gris o tizón por Botrytis cinerea fue la más severa en la variedad “Freedom” y se observó en diferentes estados de desarrollo de la planta. El hongo presentó una diversidad de síntomas desde manchas en las brácteas y hojas hasta cancros en el tallo. Se observaron masas de esporas en las hojas en infecciones combinadas con Peronospora spp. Entre las enfermedades foliares también se identificó a Corynespora spp. y Colletotrichum gloeosporioides. Una enfermedad de importancia fue la producida por Phytophthora nicotianae, el patógeno fue aislado desde tres invernaderos produciendo daños severos y pérdida total de las plantas. Rhizoctonia solani, Fusarium spp. y Pythium spp. Se identificaron desde plantas con síntomas de pudrición de raíz. Entre las enfermedades bacterianas se identificó a Pectobacterium chrysanthemi causando ennegrecimiento de las nervaduras, pudrición blanda de los tallos y marchitez de la planta acompañada de mal olor. Pseudomonas spp. se identificó desde manchas acuosas irregulares en el envés de las hojas. Los patógenos identificados pueden causar enfermedades en otras ornamentales y su diseminación en los invernaderos se produce por malas prácticas de manejo. El diagnóstico oportuno de las enfermedades en las ornamentales será determinante en la prevención de epidemias.

Palabras Clave: Flor de pascua, Enfermedades, Ornamentales, Tizón por Botrytis

CP 14P- Pink hibiscus mealybug (Homoptera: Pseudococcidae) sex pheromone: Trap protocol and field use. A. Roda, A. Francis, K. Bloem, K. Griffiths, S. Lapoint, and A. Zhang. USDA APHIS PPQ CPHST.

Although pink hibiscus mealybugs (Maconellicoccus hirsutus) attack less than 150 plant species they are only easily detected once populations reach high and damaging levels. A recently identified and synthesized female sex pheromone may provide a valuable tool to detect the pest and allow timely release of biological control agents or application of other management strategies. Field experiments conducted in Florida have determined the optimal trap type, the relative distance of attraction and the longevity of the lure. The most effective trap type had a restricted entrance which limited the number of other insects entering the trap and facilitated processing. The lure continued to attract males for more than six months but with significant decreases in trap catch after four months. Field tests also showed that the pheromone traps are often able to capture males in areas where no visual indication of an infestation is evident. Combined with visual inspection, the pheromone trap may serve as a valuable tool to detect new infestations of pink hibiscus mealybugs.

CP 15P- Efficacy of Nemacur 3EC and Vydate L applied by a drip-irrigation system for the control of phytonematodes on plantain. J. A. Chavarría¹, N. Vicente¹ and J. Ortiz². ¹Department of Crop Protection, ²Department of Agricultural Economics, University of Puerto Rico. Agricultural Experiment Station.

The efficacy of commercial formulations of Nemacur 3EC (phenamiphos) and Vydate L (oxamyl) was studied on plantain when applied by a drip-irrigation system using two rates and two intervals of application. Plantain (Musa acuminata X M. balbisiana) cv. Maricongo was spaced at 1.8 m X 1.8 m, for a population density of 3,086 plants/ha. Six treatments were arranged in a randomized complete block design with four replications. Vydate L was evaluated at 30.8 L/ha/year at a six-month interval, and at 92.6 L/ha/year at a four-month interval. Nemacur 3EC was applied at 19.3L/ha/year and at 43.3 L/ha/year, using intervals of six and four months, respectively. A treatment with Nemacur 15G at 185.2 kg/ha/year at a six-month interval was included to compare with the liquid formulations. Also, an untreated check was included to determine the efficacy of the nematicides. Results from the plant-crop showed that liquid formulations of oxamyl and phenamiphos were more effective in reducing populations of Radopholus similis, Pratylenchus coffeae and Rotylenchulus reniformis when applied at higher rates and shorter intervals. Vydate L at 92.6 L/ha/year in a four-month interval significantly improved the plant height (362.7 cm), the plant diameter (16.7 cm) and was the top yielding treatment with 13.5 kg/bunch. The granular formulation of phenamiphos (Nemacur 15G) was the second best yielding treatment with 12.1 kg/bunch. Nemacur 3EC was most effective in improving bunch weight (10.9 kg) when applied at the higher rate and the shortest interval of application. Plants from the absolute control had a height of 328.4 cm, a diameter of 15.6 cm and produced 6.4 kg bunches.

CP 16P- Sustainable agricultural practices for the management of phytonematodes on pineapple. J. A. Chavarría¹, N. Vicente¹, and W. Gandía². ¹Department of Crop Protection, University of Puerto Rico, Agricultural Experiment Station. ²Puerto Rico Land Authority.

The use of broad-spectrum synthetic pesticides with high toxicity and persistence has traditionally played a major role in the commercial production of pineapple in the Caribbean. However, pesticide use may have several inconveniences, such as the contamination of water resources and deleterious effects on non-target organisms and the environment. Local consumers and government groups are concerned about health effects of chemicals in food; they are interested in more acceptable alternatives that are economically attractive and environmentally safe. Reducing the amount of pesticides used in pineapple production has become an important goal in Puerto Rico and elsewhere in the Caribbean. A field experiment was established at Vega Baja, Puerto Rico to study the effectiveness of sunn hemp (Crotalaria juncea), African marigold (Tagetes erecta) and velvetbean (Mucuna deeringiana), in rotation with pineapple (Ananas comosus). Also, this study evaluated the soil incorporation of poultry litter during the production of pineapple. Results indicated that the sustainable agricultural practices were effective in reducing nematode population and increasing yield and fruit quality. Poultry litter was effective in increasing the number of fruits when compared with the conventional chemical-based treatment. Mucuna deeringiana was very effective in increasing fruit weigh and reducing soil populations of Rotylenchulus reniformis. Meanwhile, Crotalaria juncea and Tagetes spp. significantly increased the percentage of vitamin C in the fruit. Some treatments increased not only fruit quality but also pineapple yield, which was very close or superior to that obtained with the standard chemical treatment. Results from this research show promise and may serve as the base to find new alternatives for the commercial production of pineapple in the Caribbean.

CP 17P- Influence of the strobilurin fungicides on foliar diseases and yield of sweet corn in Florida. R. N. Raid. University of Florida, IFAS.

Common rust (Puccinia sorghi) and northern corn leaf blight (Exserohilum turcicum) are two foliar diseases of sweet corn that may cause devastating yield losses in Florida if left uncontrolled. Because of the continual emergence of new pathogen variants, host-plant resistance solely can not be relied upon. Three fungicide trials were conducted during 2004 and 2005 to evaluate the effectiveness of several strobilurin fungicides alone, in alternation, and in combination with the standard EBDC protectant, mancozeb, and the sterol inhibitors. Compounds evaluated in the trials included azoxystrobin (Quadris), pyraclostrobin (Headline), propiconazole (Tilt) and an azoxystrobin/propiconazole pre-mix (Quilt). All experiments consisted of randomized complete blocks with four replications of all treatments. Fungicides were applied on approximately a weekly basis, with the number of applications ranging from two to five. Conditions for disease development were very favorable in all three trials, with percentage foliar necrosis at harvest ranging as high as 44, 46, and 87%, thus providing for an excellent evaluation of fungicide efficacy. Although all fungicides provided for significant reductions in disease severity, the sterol inhibitors and strobilurins provided control levels far superior to that of mancozeb. Pre-mixtures or tank-mixtures of the sterol inhibitors and strobilurins were particularly effective. Yields were negatively correlated with the levels of foliar necrosis afforded by the various treatments. In one trial, percentage marketable yield ranged from 33% in the non-treated check, to 99% in the best fungicide treatment.

CP 18P- Potential leafhopper vectors of Xylella fastidiosa in Puerto Rico. B. V. Brodbeck, M. Zapata, S. Oden, Y. Marino, and P. C. Andersen. University of Florida.

The purpose of this project was to survey potential vectors of Xylella fastidiosa (Xf) in Puerto Rico. Xf is a xylem-limited bacterium that is the causal agent of citrus variegated chlorosis (CVC) in South America and coffee leaf scorch (CLS) in Central America, thus posing a threat to agriculture in Puerto Rico and the mainland US. Xf is transmitted only by xylem-feeding sharpshooter leafhoppers (Cicadellidae: Cicadellinae) and froghoppers (Cercopidae). From May 2004 through October 2005 we sampled citrus and coffee plantings in Mayagüez, Lares, San Sebastián and Adjuntas at three-month intervals with sweeps and sticky traps. Leafhoppers were also collected from alternative hosts found within coffee/citrus farms. Over 4,000 Hemiptera were collected; fewer than 5% were xylem feeders. Within coffee/citrus plantings we collected four of the six sharpshooter species previously found in Puerto Rico: Caribovia coffeacola, C. coffeaphila, Hortensia similis and Apogonalia spp. Hortensia similis was the most abundant sharpshooter and was found at all sites, but it is primarily a grass feeder and rarely collected on coffee and citrus. Caribovia coffeacola was frequently collected on coffee (< 0.2 insects per plant) and occasionally on citrus, but distribution was limited to inland mountainous plantings. Other inland farms were examined, and localized areas of high C. coffeacola densities were found (ca. 1/coffee). High C. coffeacola abundance was associated with the legume Inga vera on which immature C. coffeacola were common. Caribovia coffeaphila and Apogonalia were never collected directly from coffee or citrus. We are currently investigating the feeding behavior of H. similis and C. coffeacola on citrus and coffee to establish the likelihood of Xf transmission on these hosts.

Keywords: Sharpshooter leafhoppers, Citrus variegated chlorosis, Coffee leaf scorch

CP 19P - Farmer Participatory Research to evaluate non-chemical weed management strategies by fairtrade banana farmers in St. Vincent and the Grenadines. W. A. Isaac, W. Ganpat, R. Brathwaite, and I. Bekele. University of the West Indies.

The experience of 36 small banana farmers in St. Vincent, West Indies, who piloted a Farmer Participatory Research method to investigate a common, but serious and urgent problem, is presented. Many of the smaller Caribbean islands depend on export of bananas to sustain their economies; however, within recent times, restrictions on trade, tariffs, and quotas imposed by importing countries have seriously affected income, with resultant negative impact on standards of living. Further, in farmers’ fields, a serious noxious weed, watergrass, has taken over. This weed depletes the soil of nutrients and harbors a serious pest to banana, the root-knot nematode. Yields are reduced and plants topple very easily when affected. Further, importers have banned the use of chemical pesticides to control weeds and nematodes. Farmers must find alternative ways to control this weed problem. Since most of these Caribbean islands do not have research stations, the Banana Farmers Association joined a team from the University of the West Indies and representative farmers to engage in Participatory Research to test several alternative non-chemical approaches. Unlike previous attempts, this research was to be done on farmers’ fields. In the first stage, some 36 farmers from across the island of St. Vincent participated in a 3-day Farmer Participatory Training Workshop where they learned to carry out experiments on their farms in such a manner that results and conclusions could withstand the scrutiny of other farmers, not only in St. Vincent, but in the wider Caribbean region. They learned about treatments, controls, experimental plots, replication, randomization, sampling, data collection and record keeping, and importance of group work. Only participatory techniques, most based on experiential learning principles, were used at the workshop. In the second phase, some 36 farmers established 10 m x 10 m plots on their farms (average size of 2 ha.) for treatments and controls. Farmers tested one or two treatments out of six treatments that were pre-evaluated at the workshop and selected by them for testing. For six weeks they gathered weed data using a quadrant and kept records. A monitoring visit was made by the team of specialists from the University midway into the field exercises. This visit was to assist with solving any problems farmers were having, as well as to encourage them to continue as experimenters. The results showed that Desmodium heterocarpon, a cover crop, showed tremendous potential as a control for the watergrass. A video was done of the process to develop interest among other farmers about the process and benefits of Farmer Participatory Research. Farmers embraced this method of solving their own problems. On the basis of information received, the regional Banana Farmers Association has asked for the process to be replicated on another island and this is to be done in early 2006 in St. Lucia. Several lessons were learned: that the experimenting farmers (not their spouses) should come to the workshop; the absolute need for a facilitator to visit farmers weekly to solve any immediate problems; the need to be regular with data collection and to preciously guard data collected. In times of dwindling research funding and less extension support in the region, farmers being empowered to conduct research on their farms is a viable alternative to solving farm-related problems, not only in bananas, but in other crops and livestock production as well.

CP 20P - Introduction and spread of invasive species in Puerto Rico: Survey of intra island ferry passengers. C. I. Alamo and A. Bruguerras. University of Puerto Rico, Agricultural Experiment Station.

Puerto Rico is conducting an economic managing analysis of three invasive species. The three invasive species selected for the case studies are black sigatoka (Mycosphaerella fijiensis), the mango seed weevil (Sternochetus mangier), and the coffee berry borer (Hypothenemus hampei). A survey was conducted to determine the probabilities of introduction and spread of the studied invasive species though the intra island passenger traffic. The survey gathered information related to the introduction by passengers of carrying mango, plantain, banana, coffee and other agricultural products and vegetative material. The public ferry transportation ports surveyed are located in the east part of the island in the Fajardo municipality. There is no regular inspection program in the intra island public ferry transportation ports (Fajardo, Vieques y Culebra). The public ferry system transported an annual mean of 800,473 passengers from 2001 to 2003. Sixty- five percent of the passengers traveled the Fajardo-Vieques route, and 35.0% Fajardo-Culebra. The number of passengers surveyed was 552. The survey sample was distributed according to the annual distribution of the passengers per route. Sixteen percent of the passengers transported agricultural fresh products and 3.5% vegetative material during the interviewed trip. On a previous trip, 36.0% transported agricultural fresh products and 17.5% vegetative material. During the interviewed trip 3.1% of the passengers transported mango, 2.9% plantain, 1.8% banana, and 0.9% coffee. On a previous trip 11.6% of the passengers transported mango, 14.1% plantain, 12.0% banana, and 3.9% coffee beans.

Keywords: Invasive species, Black sigatoka, Mango seed weevil, Coffee berry borer

CP 21P- A mass trapping surveillance program for the detection of the coffee berry borer in Puerto Rico. R. A. Franqui. Department of Crop Protection, University of Puerto Rico, Agricultural Experiment Station.

The coffee berry borer, Hypothenemus hampei Ferrari (Coleoptera: Scolytidae), is widely considered to be the most devastating pest of coffee. Endemic to Central Africa, the coffee berry borer can now be found in most coffee growing regions throughout the world (Le Pelley 1968). Annual losses caused by this insect have been estimated at over $500 million. One of the most widely cited references on coffee berry borer presence in different countries is that of Le Pelley (1968), where more than 20 countries are listed as having the insect, among these Puerto Rico. A survey for the coffee berry borer in Puerto Rico in the major growing areas of Lares, Utuado, and Adjuntas, in the summer of 1998 (by F. E. Vega, G. Mercadier and N. Bayron Justiniano), followed by another survey of coffee samples from Adjuntas, Las Marías, San Sebastián, Utuado, in June 2002 (by F. E. Vega, A. Sidor, and R. Franqui), indicated that the insect was not present on the Island. In order to prevent the entrance of this devastating insect to Puerto Rico it is imperative that requirements for 10% roasting of imported coffee be strongly enforced in order to kill coffee berry borers that might be present in the coffee seeds, and that coffee be shipped in plastic bags inside cloth bags, as is currently being done. A mass trapping sampling program for the insect should be implemented in coffee growing regions, especially near roasting factories in Puerto Rico into which imported coffee is being brought in. It is also imperative to initiate an extension program aimed at providing training to coffee growers on how to identify and prevent the spread of the insect.

CP 22P- The cycad scale, Aulacaspis yasumatsui Takagi (Homoptera: Diaspididae): A survey of a new invasive pest to Puerto Rico. A. Segarra and W. Pérez. University of Puerto Rico, Agricultural Experiment Station.

Surveys of the cycad scale (Aulacaspis yasumatsui) in western Puerto Rico showed that the scale is widely dispersed and heavy infestations are common. All Cycas spp. found within the survey area were attacked. Cycas revoluta was found to be the commonest and also the most heavily attacked cycad. Mortality from the cycad scale was also found to be widespread. An encyrtid parasitoid wasp, Coccobius fulvus, was found attacking the cycad scale at all surveyed sites. Average percentage parasitism was 24.4 ± 2.9% (SE), and did not vary significantly between sampling dates. Another parasitoid wasp, the aphelinid Ablerus sp. was found, but it is likely to be a hyperparasitoid of C. fulvus. Sex ratio for C. fulvus was found to be female biased (3:1). A slight trend towards inverse density dependent parasitism was found, as scales at low density sites appear to be most heavily parasitized. Only in two instances was predation on cycad scales observed. The coccinellids Chilocorus cacti and Cryptolaemus montrouzieri were observed feeding on the cycad scale, both occurring in sites infested by other scales. Hypotheses are presented for trends in inverse density parasitism based on cycad scale settling and borrowing behavior, and for the probable introduction of the cycad scale in 1999.

Forages (FOR)

FOR 1P- Persistence, yield and nutritive value of alfalfa (Medicago sativa) varieties in a tropical environment. H. Díaz and E. Valencia. University of Puerto Rico, Agricultural Experiment Station.

Alfalfa (Medicago sativa) is the most important legume for temperate climates, but very few varieties persist more than a year in the tropics. In recent years, alfalfa Florida 99 was released by the University of Florida breeding program for use in tropical and subtropical environments. However, adaptation and yield of Florida 99 in a tropical environment is not known. A field experiment compared forage dry matter yield (DMY), vigor (plant height), percentage cover and nutritive value [crude protein (CP), and neutral detergent fiber (NDF)] of six alfalfa varieties (Florida 99, Amerigraze 401, Amerigraze 702, Pioneer 5681, Pioneer 5454 and Alfagraze). The study was conducted at the Fortuna Substation of the University of Puerto Rico on a San Antón soil (fine loamy, mixed, superactive, isohyperthermic Cummulic Haplustolls). Variables measured were DMY, plant height, percentage cover, CP and NDF at 120 d post planting. Data was analyzed by using the GLM procedures of SAS. There was no varietal effect (P>0.05) on DMY (average of 1,955 kg/ha). Nor was there any varietal effect (P>0.05) on plant height at 120 d because at this point all the plants had reached their maximum height (average of 33 cm) for tropical areas. There was however, a varietal effect was (P<0.05) on CP; Amerigraze 401 (19.9%) having higher CP than Amerigraze 702 (17.2%), a 2.7 percentage unit difference. In addition, NDF was lower (P<0.05) for Amerigraze 401 (29.5%). In general, alfalfa varieties had low NDF; e.g., NDF values for Amerigraze 702 and Pioneer 5681 were 35.6 and 36%, respectively. After two years, there was a variety effect on vigor and cover, with Florida 99 outperforming the other varieties, followed by Alfagraze. This study shows that Florida 99 and Alfagraze persist in the tropical environment of Puerto Rico; however, more information is needed on conservation management practices (e.g., hay production).

FOR 2P- Small ruminants for biological control of invasive weeds. J. P. Muir, E. Valencia, S. Weiss, and T. Terrill. Texas Agricultural Experiment Station.

The invasion of fallow cropland, pasture and woodland by native and non-native weeds is a common problem throughout the Caribbean and southern USA. In Florida alone, 29% of non-cultivated plants are classified as non-native. Coral vine (Antigonon leptopus), cogongrass (Imperata cylindrica), Japanese climbing fern (Lygopodium japonicum), and leucaena (Leucaena leucocephala) are well documented examples of non-natives that have become widespread invasive species in the Caribbean. The use of intensive, short duration goat/sheep browsing (ISDGB) may be an efficacious, remunerative, and ecologically mild form of manipulating unwanted vegetation. Growing concern with invasive plants, in conjunction with a strong small ruminant market, provides a fortuitous opportunity to combine profitable animal husbandry with biological control of weeds. Both stocking rates and rotations have proven important in reducing perennial brush using small ruminants. But the key word is “reduction” and not “eradication.” Even when heavy stocking rates force intensive browsing, goats and sheep cannot always completely destroy target species and these can still make a comeback in subsequent years from rootstocks or soil seed banks. Timing for ISDGB or combinations of different weed control methods that include ISDBG may have to be developed to ensure long-term eradication. An additional concern is the potential damage to non-target plants such as desirable native species. The commercial application of ISDGB requires greater knowledge, including effects of prior vegetation manipulation, season of application, stocking rates, duration of exposure, and growing conditions, all of which combine to affect the degree of successful weed control and subsequent survival of desirable native species. A consortium of researchers in Puerto Rico, St. Croix, and the southeastern USA, with the assistance of a Southern Sustainable Agricultural Research and Education grant, is currently studying how best to implement ISDGB.

FOR 3P- Morphological characterization of Desmodium spp. for forage in the Caribbean Basin. E. Valencia¹, R. Ramos¹, A. A. Rodríguez², and K.H. Quesenberry³. ¹Agronomy and Soils Department, ²Animal Industry Department, University of Puerto Rico - Mayagüez Campus and ³University of Florida, IFAS.

The successful introduction of tropical forage legumes into pasture and livestock feeding systems of the tropics has been limited. In the genera Desmodiums, there exists a large collection of accessions that have not been catagorized for morphological and chemical characteristics. The objective of this study was to assess morphological characteristics (plant architecture, percentage spread, date of flowering, and seed production) and chemical composition (total tannin concentration) of four accessions of D. incanum and three accessions of D. heterocarpum. Single plants of four accessions of D. incanum and three accessions of D. heterocarpum were established on soils of the Corozal series (fine clay, mixed, isohypertermic Aquic Haplohumults) in a randomized complete block with four replicates. Measurements on plant architecture and spread were taken biweekly and date of flowering was determined. Leaves and twigs (500 g) were collected from established plants, and freeze-dried to determine total tannin analysis. Freeze-dried samples were compared with oven-dried samples. Performance was variable among the seven accessions. Plants exhibited a shrubby growth habit, and spread was limited and varied (P<0.05) from 10 to 15% cover. There were differences in plant height (ranging from 41 to 69 cm); D. heterocarpun PI 9119 was the tallest plant and D. incanum PI 219839, the shortest. Percentage flowering was not different among accessions, and only the three D. heterocarpun accessions produced small amounts of seeds. There was also great variability among accessions on extractable tannin concentration, with a high of 54 and 62% for D. incanum PI 322521 and PI306272, respectively. The tannin extractable fraction was low for the three D. heterocarpun accessions (4.3%). There was great variability among the species for protein and fiber-bound tannins also, and fiber-bound tannins were much lower in oven-dried samples than in freeze-dried samples. Preliminary results suggest that both species, D. incanum and D. heterocarpun, may persist and adapt to Ultisol conditions, but that seed production would be a limitation. The variability of the tannin concentration in D. incanum offers potential to assess nutrient intake and utilization by ruminants and thus to determine tannin effects on gastrointestinal nematodes in small ruminants.

Food Safety and Value Added Products (FS-VA)

FS-VA 1P- Incidence of Escherichia coli O157:H7, Listeria monocytogenes and Salmonella spp. in the raw milk of the bulk tank of dairy industries in Puerto Rico. M. Flores, L. E. Orellana, W. Rodríguez, and L. Ponce de León. Food Science and Technology Program, University of Puerto Rico - Mayagüez Campus.

The production of fresh milk is one of the most important agricultural industries in Puerto Rico. For this industry, monitoring activities are important to ensure that the product is safe and of good quality. Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella spp. are food borne pathogens that can be present in cattle and as a consequence in milk. These pathogens can cause several human foodborne illness and animal infection that can cause losses to the dairy industry. The consumption of raw milk, inadequate pasteurization and/or contamination after processing are just several causes of big outbreaks in the population. Puerto Rico has no statistics about milk foodborne illness or the presence of those pathogens in raw milk. The objective of this study was to determined incidence of E. coli O157:H7, L. monocytogenes, and Salmonella spp. in refrigerated tanks where raw milk is stored. The distribution of dairy herds in Puerto Rico is heterogeneous and is divided into four regions (Arecibo, Caguas, Mayagüez, and San Juan). For this study, 10% of the 37 dairy herd industries in Puerto Rico were analyzed. Traditional and rapid methods were used to determine the presence of foodborne pathogens in raw milk. The confirmation by rapid methods shows the presence of Salmonella in only four dairy herds; two from the region of Arecibo and the other two from the region of Caguas. The absence of E. coli O157:H7 and L. monocytogenes as well as the low incidence of Salmonella indicate that Good Agricultural Practices are being used in the dairy herd industry. Future studies are necessary in order to determine why Salmonella was the only pathogen present in the refrigerated tanks.

FS-VA 2P- Antimicrobial activity of essential oils from Thymus vulgaris and Origanum vulgare against foodborne pathogens in minimally processed foods. I. Muñoz and L. E. Orellana. Food Science and Technology Program, University of Puerto Rico - Mayagüez Campus.

Fruit and vegetable consumption has been increasing in the last years. Consequently, the post-harvest agricultural practices have changed in order to supply the increased demand of the market. Food production and distribution chains have contributed to the increase of foodborne diseases caused by minimally processed foods. The objective of this study was to determine the effectiveness of carvacrol and thymol as antimicrobial agents in lettuce, tomato and pepper. Thymol and carvacrol are major components of essential oils from Thymus vulgaris and Origanum vulgare. The oils were tested on Escherichia coli O157:H7, Pseudomonas aeruginosa and Listeria monocytogenes, in vitro, and also were tested directly on the vegetables. The vegetables were purchased at a local supermarket and were washed with chlorinated water (3 ppm) before each was inoculated in a one-inch square with 1 ml of each bacteria and 15 μl essential oil component, using 1%, 1.5% and 2% concentrations. In general, carvacrol and thymol had an inhibitory effect on the growth of Listeria monocytogenes, Escherichia coli O157:H7 and Pseudomonas aeruginosa in all products tested. A concentration of 1.5% of thymol and carvacrol was the most effective to inhibit the growth of all bacteria under in vitro conditions; it showed the greatest inhibition zones. In vivo conditions using thymol at 1.5% concentration inhibited the growth of E. coli O157:H7 and P. aeruginosa in tomato and lettuce but had little effect on the growth of L. monocytogenes. This research has confirmed the effectiveness of carvacrol and thymol as antimicrobial agents and indicates a possible alternative to decrease foodborne disease outbreaks from minimally processed foods.

FS-VA 3P- Shelf-life study of pork cuts marinated and vacuum-packed. A. M. Malavé, L. E. Orellana, E. Negrón, and C. Santana. Food Science and Technology Program, University of Puerto Rico - Mayagüez Campus.

The pork industry in the world has undergone a transformation responding to today’s consumer demands. Changes in life style and nutritional habits have promoted the production of pork meat with lesser fat content. Also, new alternatives for meat products are being sought for added value products. The objective of this study was to determine the shelf-life of pork cuts marinated and vacuum-packed. For the shelf-life study, the growth of anaerobic microorganisms, coliforms/E. coli, molds and yeast, Pseudomonas spp., in addition to the pathogenic microorganism Yersinia enterocolitica, were determined. The pH, water activity (aw) and color were measured to evaluate physicochemical characteristics and quality of the product. The pork cuts before marination, the spices and the finished product at 0, 1, 4, 8, 12, 16, 20, 24, 26 and 34 days were evaluated. The experiment was repeated on three occasions. During the sampling period the pH and water activity did not undergo significant changes. The finished product maintained a pH of 5.90 and water activity of 0.991. In addition, the color of the meat was acceptable throughout the sampling period. The shelf life of the pork cuts marinated and vacuum packed was 34 days at 4° C. The shelf-life of fresh pork products is relatively short; therefore, increasing shelf-life using value-added techniques has become a commercial necessity that allows new product development and greater distributions chains.

FS-VA 4P- The Caribbean Crop Nutrition Network. G. Gouveia. University of West Indies.

The Caribbean Crop Nutrition Network is a newly formed regional body whose mandate is to be a dynamic association comprising of members who have keen interests in revolutionizing the status of agriculture across the Caribbean. Conceived of in January 2006, the Network has subtly enhanced regional cohesiveness, through the agreement to utilize and apply contemporary and internationally approved science and technology to the traditional fertilization practices in the Caribbean. The technology in question thus far presents itself in the form of decision support tools developed by Yara International ASA, an international fertilizer company, with whom the Department of Food Production, The University of the West Indies, St. Augustine, Trinidad, and ultimately the Caribbean Crop Nutrition Network, have aligned themselves. These decision support tools include the N-Tester, which is an easy-to-read, efficient and lightweight chlorophyll gauge. Other tools will primarily be exposed to members of the Network as they are issued. The energy of the Network will be manifested in the following ways: (1) Concurrence from participating institutions to facilitate continued progress of the group; (2) Regular interfacing with agricultural professionals and technicians in the respective territories to facilitate the realization of the objectives; (3) Recurrent collaborator-collaborator and collaborator-coordinator communication on matters pertaining to the Network and to the agriculture industry; and (4) Congregate at a mutual location bi-annually to elaborate on skills possessed, acquired and or required to enhance institutional collaboration and contributions to the field of agriculture-- specifically to nutrition and fertilization of plants. The Caribbean Crop Nutrition Network is a non-profit body, whose sole purpose is to make significant contributions to the Caribbean’s agricultural sector. We welcome other interested organizations to join us in this revolutionary struggle to revitalize Caribbean agriculture.

FS-VA 5P- Inhibitory disc diffusion assays of antioxidants on foodborne pathogenic bacteria. N. Arroyo and M. Velázquez. University of Puerto Rico, Mayaguez Campus. Food Science and Technology Program.

The purpose of this research was to find the minimum inhibitory concentration (MIC) in an in vitro assay of the antioxidants ascorbic acid, naringenin, and quercetin against the foodborne pathogens Escherichia coli serotype O157:H7 and Staphylococcus aureus and the opportunistic pathogen Pseudomonas aeruginosa. Inhibition zones were recorded by using a broad range of concentrations from 10,000 to 1 microgram/ml on Escherichia coli serotype O157:H7, Staphylococcus aureus and Pseudomonas aeruginosa. The MIC for the antioxidants ascorbic acid and naringenin were 1 microgram/ml for P. aeruginosa and E. coli serotype O157:H7, respectively. The MIC for quercetin was 1 microgram/ml on E. coli serotype O157:H7 whereas high concentrations of the antioxidant were required to inhibit S. aureus (MIC of 5,000 microgram/ml) and P. aeruginosa (MIC of 7,500 microgram/ml). Low concentrations (1 microgram/ml) of the antioxidants ascorbic acid and naringenin were effective on some of the evaluated bacteria (P. aeruginosa and E. coli serotype O157:H7) and therefore could be incorporated into foods. The antioxidant quercetin was effective against the pathogenic bacteria Escherichia coli serotype O157:H7 at low concentration (1 microgram/ml) whereas inhibition against S. aureus and P. aeruginosa required concentrations that, if used as food additives, would have a negative effect on the organoleptic properties of the foods. The assessment of the effective antioxidant concentration to eliminate these bacteria can be useful in developing value-added and safe food products.

Keywords: Antioxidants, Minimum inhibitory concentration, Foodborne pathogenic bacteria

FS-VA 6P- Determination of the incidence of Escherichia coli serotype O157:H7 in carcass during the slaughter process. M. Oquendo. University of Puerto Rico, Mayagüez Campus, Food Science and Technology Program.

The main objective of this investigation was to evaluate the incidence of Escherichia coli O157:H7 in cattle during the slaughter process in Puerto Rico. The slaughter houses visited were located in Mayagüez, Arecibo and Yauco. The purpose of the investigation is to evaluate the actual methods of reduction of bacterial counts and the prevention of food borne pathogens. The system used was the one proposed by the USDA for the recollection of samples for the detection of E. coli O157:H7 using the method of polyurethane sponges. The animals used for the investigation were classified by race and age. The results for the presence of E. coli O157:H7 in the carcass prior and after the wash were negative. The bacterial counts in the samples were very low throughout the investigation. The statistical analysis used was the MacNemar test, which resulted in non significant differences with the treatment applied to the carcass. The Wilcoxon test analysis was performed to compare the reduction of bacterial counts in the carcass; these values fluctuated, depending on the slaughter house (p<0.05). The results of the serological tests performed indicated the presence of E. coli, and a possible Enterobacter aerogenes and Enterobacter cloacae. The slaughter houses visited use Good Manufacturing Practices (GMPs), and followed their HACCP plans.

Keywords: Escherichia coli O157:H7, Enterobacter cloacae, Enterobacter aerogenes

Horticulture (HORT)

HORT 1P- Fruit quality traits and yield of nine carambola cultivars grown at three locations in Puerto Rico. R. Goenaga, E. Rivera, and A. Marrero, USDA - ARS Tropical Agriculture Research Station (TARS).

Nine carambola (Averrhoa carambola) cultivars grown on an Oxisol, Ultisol, and Mollisol were evaluated for four years under intensive management at Isabela, Corozal and Juana Díaz, PR, respectively. There were no significant differences in number and weight of marketable fruits per hectare between Juana Díaz and Isabela; average values for both locations were 263,969 fruits/ha and 32,033 kg/ha. At Corozal these values were 248,343 fruits/ha and 28,867 kg/ha, respectively. There were no significant differences in weight of marketable fruits per hectare among cultivars B-17, Thai Knight, and Sri Kembangan between locations. The average marketable fruit weight for these higher yielding cultivars was 36,060 kg/ha. Arkin and B-16 were the lowest yielding cultivars, averaging 23,490 kg/ha of marketable fruits. Cultivar Kari produced significantly longer fruits at all locations, whereas cultivar B-16 produced the shortest fruits. Significantly higher brix values were obtained from fruits of cultivar B-17 at all locations whereas lower values were obtained from those of Arkin.

HORT 2P- Phenotypic characterization of the USDA-ARS Tropical Agriculture Research Station Banana Germplasm Collection. B. M. Irish and R. Goenaga. USDA - ARS Tropical Agriculture Research Station (TARS).

Banana [Musa acuminata Colla. (AA, AAA); Musa x paradisiaca Colla. (ABB, AAAB, AABB)], are large monocotyledonous plants in the Musaceae. Banana is one of the world’s most important food crops. High genetic diversity can be found in centers of origin, but the lack of diversity in commercial production is evident. To prevent loss of genetic resources, a germplasm collection has been established for banana. The goal of the current research is to maintain clonally propagated germplasm collections of banana, to phenotypically and genotypically characterize accessions in order to assess genetic diversity, horticultural identity, and to identify potentially superior genotypes. Characterization efforts focus on passport, management, site, phenotypic and genotypic descriptors, and evaluation data. First season phenotypic data (mother crop) has been collected and a second season (1^st ratoon) is under way. Phenotypic traits of agronomic importance include: bunch weight, number or hands, as well as days to flowering and days to maturity. Phenotypic data for plantain [Musa x paradisiaca Colla. (AAB)] was recently included in the USDA-ARS, Germplasm Resources Information Network (GRIN) database and can be accessed in the GRIN website (http://www.ars-grin.gov). Accessions being characterized are available for distribution for research purposes.

HORT 3P- Shade and water stress reduce water requirement in detriment of flower production of anthuriums. R. A. Arancibia. University of the Virgin Islands.

In spite of the favorable conditions to grow horticultural crops throughout the year in the U.S. Virgin Islands (USVI), production is restricted because of water deficit particularly during the dry season (December to August). The average rainfall in the USVI is 70% of the pan evaporation, but the deficit is even greater during the dry season. Shade-loving anthurium is being used to develop a water sustainable production system for USVI growers. Under shade, plants require substantially less water because of reduced light, temperature, and wind that result in less evapo-transpiration. In addition, many tropical high value ornamentals perform better in shady conditions and are highly demanded by the local tourist industry. System automation and irrigation scheduling were evaluated at -10, -30, and -50 kPa for anthurium production in 1.2 x 1.2 m beds with soilless media. During the rainy-season, rainfall was sufficient to maintain soil moisture levels below 10 kPa and the automatic system did not allow irrigation to start. In the dry-season rainfall was substantially lower than evapo-transpiration and automatic irrigation was initiated at -10 kPa. At lower soil moisture levels the probes (Watermark) appear to lose contact with the media since reading became erratic and inconsistent. Two shade levels (60% and 80%) were also evaluated in relation to evaporation, water requirements, and production. Evaporation under shade was reduced to 51% and 36% of that under direct sun for 60% and 80% shade, respectively. Wind reduction under shade structure may have played a significant role in this difference. Flower production after five months was higher at 60% than 80% shade and production at -10 kPA was higher than at the other treatments. These results suggest that water requirements of shade- loving plants are less than for full sun crops, and that using water stress strategies to save water reduces production.

HORT 4P- Development of methods for the genetic transformation of common bean through electroporation. L. Aranda, T. Porch, and J. Beaver. USDA - ARS Tropical Agriculture Research Station (TARS).

Common bean (Phaseolus vulgaris L.) is the most important food legume in the world, especially for small farmers in developing countries. Many breeding objectives, such as resistance to herbicides, require the development of transgenic methods in crops. Genetic transformation in common bean has been achieved by using biolistic- and Agrobacterium-based methods, but with low efficiency. The objective of this study was the development of methods for pollen electroporation mediated transformation in common bean. Two common bean cultivars, Morales and Tio Canela 75, were selected for study. Pollen germination media, electroporation voltage, electroporation methods, and pollination methods were evaluated. Pollen germination media were tested with varying sucrose, calcium, and other nutrient concentrations and the medium yielding the highest pollen germination was selected. To determine the appropriate voltage, several biological dyes were tested for incorporation in pollen, and aniline blue was found to be the most effective. By varying voltage and testing germination post-electroporation, electroporation voltages of 1000 to 5000 volts/cm were tested. It was determined that 4000 volts/cm yielded the highest level of dye incorporation while maintaining pollen viability. In addition, cuvette-versus electrode-mediated electroporation and four pollination methods were tested and the methods yielding the highest efficiencies were applied in transformation experiments. Transformation with the bar gene, conferring herbicide resistance, was tested with Morales and Tio Canela 75. The results of these transformation experiments are currently being evaluated.

HORT 5P- “IDIAF navideño”: Una nueva variedad de guandul (Cajanus cajan L. Millsp) en República Dominicana. J. R. Cedano, J. Nin, F. Oviedo y S. Nova. Instituto Dominicano de Investigaciones Agropecuarias y Forestales (IDIAF).

Las variedades de guandul (Cajanus cajan L. Millsp) cultivadas en la República Dominicana tienen bajos rendimientos y son susceptibles a plagas y enfermedades debido a su escasa diversidad genética. En la última década se ha incrementado la demanda interna y externa de guandul fresco por los diferentes integrantes de la cadena agroalimentaria. Con el objetivo de proveer a los productores de guandul de variedades de alto rendimiento y tolerantes a plagas y enfermedades, se desarrolló la variedad de guandul 'IDIAF Navideño'. Esta variedad se obtuvo en la Estación Experimental Arroyo Loro del Instituto Dominicano de Investigaciones Agropecuarias y Forestales (IDIAF) en San Juan de la Maguana, durante el período 1996-2005, mediante selección masal del compuesto Desatalío de líneas criollas segregantes. Esta nueva variedad se sometió a presión de selección con la presencia de enfermedades y estrés abióticos durante nueve ciclos. Esta variedad tiene hábito de crecimiento indeterminado, ramas colgantes, con buena distribución de las vainas desde la parte media hacia arriba, tiene granos grandes, porcentaje de desgrane alto (62%) y buenos rendimientos de grano verde (7,000 kg/ha). Produce bien desde 0 a 1,500 msnm. Es de ciclo vegetativo intermedio, florece durante días cortos (sensible al fotoperíodo); es tolerante a roya (Uromyces cajani L.), antracnosis (Collectotricum cajan Rangel), escoba de bruja (Blactomosis sp) y susceptible a bacteriosis común o cáncer del tallo (Xanthomona campestri pv cajani L.). Puede producir con 350 mm de lluvia distribuidos durante su ciclo vegetativo y tolera hasta 2,500 mm. Esta variedad tiene buenas características culinarias, es de cocción relativamente rápida y tiene buena aceptación entre consumidores y procesadores de guandul fresco.

One hundred twenty thousand, stage-four plantlets of pineapple [Ananas comosus (L.)] cv. Cabezona, were produced for the Hard Crop Company in Lajas, Puerto Rico. Multiple shoots were obtained from dormant auxiliary buds excised from mature fruit crowns and grown in Murashige & Skoog (MS) medium supplemented with benzyl adenine, BA (0.5 mg/L) and naphthalene acetic acid, NAA (0.1 mg/L). A production of roots was obtained in the media containing indole-3-butyric acid, IBA (0.2 mg/L) and NAA (0.2 mg/L) without activated charcoal. Once developed to stage three, the plantlets were transferred to the greenhouse, where they were developed to stage-four and then planted in the field. It is the first time the University of Puerto Rico Agricultural Experimental Station has developed a successful commercial pineapple production of cv. Cabezona for a private company in Puerto Rico. In Project, Z-171 “Micropropagatión and Improvement of Pineapple cv. Cabezona”, it was possible to rescue and develop true to type material to the Cabezona variety, pathogen free. It was also possible to train eight graduate students in pineapple micropropagation techniques in Puerto Rico.

HORT 7P- Micropropagation of pineapple [Ananas comosus (L.) Merr.] cv. Cabezona using different concentrations of hormones. E. M. Lizardi, L. N. Avilés, J. Escudero, S. Martínez, and E. Rodríguez.

New protocols were developed for the production and micropropagation of pineapple [Ananas comosus (L.) Merr.] plantlets cv. Cabezona in Puerto Rico. The Cabezona pineapple is an economically important variety in the southwestern part of Puerto Rico where it is produced solely. Under the Project H-390 “Better Horticultural Practice for Crops of Economic Importance in Puerto Rico”, selected material was collected and propagated to increase the fruit weight average and maintenance of its varietal identity. The plants selected were obtained from a private farm in the municipality of Lajas and from the USDA National Germoplasm Depository Collection. Murashige & Skoog (MS) media, supplemented with different concentrations of the growth regulators benzyl adenine, BA (0.0, 0.125, 0.25, 0.5, 1.0 mg/L) and dichlorphenoxyacetic acid, 2,4-D (0.0, 0.025, 0.05, 0.1, 0.2 mg/L), and Phytagel (2.0 g/L) was used for the propagation in vitro. The effects of different hormone concentrations were evaluated in the production of bud, callus and roots. The rate of shoot multiplication varied in different cytokinin and auxin treatments. Among the treatments, MS medium supplemented with BA (0.25 mg/L) and 2, 4-D (1.0 mg/L) produced the highest number of calluses. MS medium supplemented with concentrations of BA (0.25-0.5 mg/L) and 2,4-D (0.025-0.2 mg/L) produced the highest number of shoots. MS medium supplemented with indole-3-butyric acid, IBA, (0.2 mg/L) and naphthalene acetic acid, NAA (0.2 mg/L) produced the highest number of roots in the laboratory. These were then transferred to the greenhouse. Sixty days later, stage-four plantlets produced appropriate root growth in the greenhouse and were then transferred to the field. Ninety-five percent (95%) of survival was achieved. Approximately 16,000 pineapple plantlets were produced with this protocol.

HORT 8P- Coffee (Coffea arabica) response to rejuvenation pruning in a Pithecellobium carbonarium agroforestry system and full sunlight condition in the mountainous region of Puerto Rico. C. A Flores¹, M. A. Muñoz², J. O’Hallorans², K. Quiñones², and C. Zayas². ¹Horticulture Department, ²Agronomy and Soils Department, Agricultural Experiment Station, University of Puerto Rico, Mayagüez Campus.

Severe pruning is considered a normal practice among coffee farmers to rejuvenate a deteriorated plantation and to re-establish production in a minimum of time and cost. Drastic changes in plant structure occurred as well as microclimate changes after the elimination of the total foliage, considered a protection canopy during years of establishment. It has been suggested that shading in coffee trees creates a better environment during the recuperation after a severe pruning. Shading seems to benefit the plantation during the critical period of recuperation and to help with stand during drought periods; it reduces evapotranspiration, wind damage, and sun burn of new leaves; and increases fruit size. No studies have been performed in Puerto Rico to describe coffee tree development after a drastic pruning of trees under shade agro forestry dynamics vs. under full sunlight conditions. The experiment was established at the Agricultural Experiment Station in Adjuntas, located in the central mountainous region of the island. Coffee plantation re-establishment was evaluated after a rejuvenation pruning of trees (var. Puerto Rico 401) cultivated under Pithecellobium carbonarium permanent shade for 12 years. This species is a leguminous tree that has good adaptation in the mountainous region and a potential species for coffee because of its fast growing habits, low density canopy and its capacity to fix nitrogen. Shade was eliminated in one section of the pruned plantation to compare its recuperation with that of the shaded section of P. carbonarium. Tree growth and canopy development were evaluated. Microclimate was monitored every 30 minutes for two years. Environmental data was collected during two years by using the automatic sensors for storing data, HOBO^® H8 Pro Series logger and a BoxCar^®Pro 3.6 software and PC interface for operation. Preliminary evaluation dictates the benefits of permanent shade from P. carbonarium in the rejuvenation of coffee trees. Initial growth was higher and more vigorous under shade than the full sunlight treatment. Also, canopy volume of trees under permanent shade presented a higher average than the full sun treatment. The only difference detected in terms of microclimate changes were the soil maximum temperatures. Trees located in full sunlight presented a higher cumulative soil temperature than the shaded trees. These ongoing studies will continue for two additional years to evaluate coffee production and bean quality.

HORT 9P - Papaya production under three different spacing regimes. J. Kowalski and T. W. Zimmerman. University of the Virgin Islands.

Papaya is a popular tropical fruit in the Virgin Islands and is widely grown by small farmers. The use of space is extremely critical to small farmers in order to utilize their limited resources for maximum production. The objective of this research was to determine the spacing requirements for optimal production, using selected papaya varieties; ‘Maradol, ‘Tainung’, ‘Trini x Washington’ and ‘Yuen Nong’) at three spacing regimes. The spacings applied were 3 m x 3m, 3 m x 2 m and a staggered double row of 3 m x 1 m. Data was collected on the stem diameter, height to first flower, height to first fruit and number of fruit. Plant spacing did not affect height to first flower or height to first set fruits. Fruit size was significantly influenced by plant spacing for varieties ‘Maradol’; and ‘Yuen Nong‘. The three plant spacing regimes did not affect stem diameter. Though limited water was applied during the course of this research, the results did provide a baseline for production under growing conditions with adequate rainfall. Under these ideal conditions, plant spacing has an effect on fruit size only within certain papaya varieties.

Roots and Tubers (R&T)

R&T 1P- Establishment of in vitro cultures of 22 field grown cassava varieties from the Corozal Agricultural Experiment Station in Puerto Rico. A. M. Correa and D. Siritunga. Department of Biology, University of Puerto Rico – Mayagüez Campus.

The importance acquired by cassava (Manihot esculenta) in the last years, due to its multiple uses including human and animal feeding and industrial purposes, has created the necessity to increase its cultivation. One of the limitations to achieving this goal has been the insufficient availability of plant material propagated by traditional methods. Furthermore, plant systematic infections (e.g., viruses) can be transmitted by the propagation of material in successive generations, limiting the maintenance of the germplasm. Through the in vitro propagation of cassava it is possible to satisfy all the current necessities of material multiplication and to solve the problem of seed insufficiency and infections. Twenty-two cassava varieties are propagated in the Corozal Agricultural Experiment Station in Puerto Rico and little is known about the genetic diversity within this population. In order to maintain this cassava germplasm for a prolonged time and for the analysis of genetic diversity, we have transferred the 22 cassava varieties from field conditions to in vitro cultures. For the micropropagation process, nodal explants of field-grown cassava were sterilized, cultured in semisolid MS shoot multiplication medium and incubated at 26˚ C under 12-hour light/dark periods. Varieties that do not readily produce roots are being micropropagated in modified MS shoot multiplication medium. We will present here the sterilization method, media compositions and in vitro growth conditions necessary for the movement and establishment of the 22 cassava varieties from the field to the laboratory.

R&T 2P- Tanier production in a poorly drained upland clay soil with a perched water table. V. A. Snyder, A. González, A. Beale, and M. A. Vázquez. University of Puerto Rico, Agricultural Experiment Station.

Production of tanier (Xanthosoma spp.) in the Caribbean region has been severely affected in recent decades by the incidence of a condition known as “root dry rot”. Research in Puerto Rico has shown that in well drained soils under good nutrient management and ample water supply through drip irrigation, incidence of root dry rot can be controlled to allow consistently high yields. In poorly drained soils, evidence has indicated that sustainable tanier yields can be obtained if the soil is well structured and the crop is grown on ridges with drip irrigation. However, the success of this practice under very poorly drained conditions, relative to results when tanier is planted on the flat, has not been documented. We conducted a field experiment on a poorly drained Ultisol (Aquic Tropudults) in the humid upland region of Puerto Rico. Tanier production was compared under three main treatments:1) planting on ridges; 2) planting on ridges, with perforated tile drains placed under the ridges; and 3) planting on flat ground. Treatments were replicated four times, in a randomized complete plot arrangement. Perforated PVC pipes were installed to monitor water table fluctuations throughout the growing season. During most of the growing season, a perched water table existed within 50 cm of the soil surface, indicating that high water tables can be problematic even under upland conditions. Mean yields of marketable cormels were 19.9, 17.7 and 5.4 Mg/ha for ridges, ridges with tile drains, and flat planting, respectively. Results were consistent with previous observations that adequate tanier yields can be obtained in poorly drained soils by planting on ridges and maintaining adequate water supply.

R&T 3P- New fertigation recommendations for cassava in non-traditional production system. E. Román and D. Sotomayor. University of Puerto Rico, Agricultural Experiment Station.

Cassava (Manihot esculenta Crantz) is well adapted to low fertility soils and tolerates long periods of low soil moisture. Although the area extent of cassava production has reduced dramatically in recent years, it is still traditionally planted in the central mountainous regions and in well-drained Oxisols in the northwestern part of Puerto Rico. As with other root crops, an increasing tendency of switching production to the southern semiarid coast of Puerto Rico is observed. In this region, soils are fertile with high cation exchange capacity and low rainfall, and farmers commonly use microirrigation and fertigation for crop production. Fertilizer recommendations for cassava production are based on studies conducted decades ago in low pH, low fertility Ultisols without microirrigation. A cassava (cv. Serrallés) fertilizer-production trial was established at the Lajas Agricultural Substation during 2002 in Fraternidad clay (Typic Haplusterts). The conventional recommended fertilization rate (275-50-250-60 kg/ha of N, P₂O₅, K₂O, and MgO, respectively) was compared with the same rate via fertigation. Three additional fertigation rates were tested: a reduced N treatment (100-50-250 kg/ha, N-P₂O₅-K₂O); reduced K treatment (100-50-125 kg/ha, N-P₂O₅-K₂O); and no K (100-50-0 kg/ha, N-P₂O₅-K₂O). Magnesium application was unnecessary because of high-soil test value observed in these soils. Fertigations were performed monthly with the N, P, and K sources as urea, phosphoric acid, and potassium chloride, respectively, whereas the conventional treatment was split, applied at four and six months after planting. Mean total yields, average root weight, and number of roots/ha obtained seven months after planting were 7,229 kg/ha, 0.17 kg/root, and 42,929 roots/ha, respectively. There were no significant differences among treatments. Reduced fertilizer applications can be recommended for cassava in these soils.

R&T 4P - Prácticas de manejo de fertilizante para la producción de raíces y tubérculos en un suelo Mollisol semiárido de la costa sur de Puerto Rico. J. M. O' Hallorans, L. E. Rivera, y W. I. Lugo. Universidad de Puerto Rico, Estación Experimental Agrícola.

La producción de raíces y tubérculos en Puerto Rico ha estado concentrada mayormente en la región central de la isla donde predominan los suelos Ultisoles meteorizados. La mayor parte de la información disponible sobre la fertilización para estas cosechas está basada en la producción en suelos ácidos Ultisoles. En los últimos años se ha observado un aumento en el número de plantaciones de ñames (Dioscorea spp.), batata (Ipomoea batatas) y yautía (Xanthosoma spp.) en la región semiárida de la costa sur de Puerto Rico. Este movimiento de la producción de estos cultivos hacia la costa sur se debe a la facilidad de mecanización tanto por la topografía de la región como por la textura de los suelos. El manejo intensivo de la mecanización y del riego agrava el riesgo de contaminación de aguas subterráneas y superficiales por la pérdida de fertilizante. Se establecieron experimentos en la Estación Experimental Agrícola de Juana Díaz, localizada al sur de Puerto Rico, con el propósito de evaluar el efecto de niveles de nitrógeno y frecuencia de aplicación del fertilizante por las líneas de riego en el comportamiento y producción de ñame y batata. Los resultados demuestran un mayor rendimiento de ñame con la aplicación de 168 kg/ha de nitrógeno en cuatro fertigaciones. Sin embargo, no se observaron diferencias significativas en rendimiento con cuatro, ocho, o 12 fertigaciones. En batata no se observaron diferencias significativas en rendimiento con la aplicación de 0, 28, 56 y 112 kg/ha de nitrógeno. Estos resultados demuestran la necesidad de basar las recomendaciones de fertilizantes en el contenido de nutrimentos del suelo y del agua de riego. Hacer una recomendación universal para un cultivo puede traer consecuencias negativas tanto para el cultivo como para el medio ambiente.

Palabras Clave: Prácticas de manejo, Fertilizante, Raíces Tubérculos, Mollisol

General Agriculture (GENAG)

GENAG 1P - Pioneros de la sustentabilidad agrícola: Caracterización y reflexiones sobre el surgimiento de una agricultura alternativa en Puerto Rico. V. Carro y A. E. Guptill. Universidad de Puerto Rico, Estación Experimental Agrícola.

A fines de 1998 la Iniciativa sobre Desarrollo Agrícola Sostenible del SEA, en colaboración con la Estación Experimental Agrícola y el programa SARE-USDA, auspició un pequeño estudio sobre el sector agrícola que denominamos "alternativo" en Puerto Rico. El estudio se organizó alrededor de cinco preguntas importantes para orientar los esfuerzos institucionales dirigidos al sector: (1) ¿Quiénes son los productores alternativos en Puerto Rico y qué tipos de proyectos están operando? (2)¿Qué están haciendo diferente a lo convencional? (3)¿Qué problemas han confrontado en sus proyectos y cuáles están aún sin resolver? (4) ¿Cuáles son los planes futuros de los productores alternativos? (5)¿Cómo puede contribuir el Colegio de Ciencias Agrícolas al proceso de crear un sistema agroalimentario más sostenible? Esta presentación resume los resultados de ese estudio y actualiza, a base de investigaciones más recientes, las lecciones que el surgimiento de un sector agrícola "alternativo" en Puerto Rico ofrece para nuestra economía, desarrollo agrícola y seguridad alimentaria general.

Palabras Clave: Agricultura alternativa, Sustentabilidad agrícola, Desarrollo agrícola

PO Box 10163

San Juan, PR 00908-1163

Tel. (787) 722-0871 /722-0291

Fax (787) 723-8512

Estado Libre Asociado de Puerto Rico

Fondo Integral para el Desarrollo Agrícola de Puerto Rico
Subsidiaria de la Autoridad de Tierras de PR

Misión

Fomentar la inversión de capital privado en la industria agrícola en general, proveyendo una financiación y capitalización adecuada para desarrollar, mejorar y crecer la capacidad productiva agrícola.

Visión

Fondo Integral para el Desarrollo Agrícola de Puerto Rico (FIDA) es una Corporación Pública, que brinda apoyo económico, viabilizando proyectos agrícolas y agroindustriales en Puerto Rico. Fomenta y desarrolla la agricultura, creando empleos y promoviendo un movimiento económico favorable para Puerto Rico.

Creación

El 30 de octubre de 2001, la Junta de Gobierno de la Autoridad de Tierras de Puerto Rico aprobó la creación de FIDA, como una corporación pública subsidiaria de la Autoridad de Tierras de Puerto Rico. El 9 de enero de 2002, se firmó la autorización y certificación como una subsidiaria de la Autoridad de Tierras de Puerto Rico. Se creó para fomentar, financiar, invertir, incentivar, promover, organizar, subsidiar y de cualquier otra forma o manera, desarrollar y potenciar el desarrollo agro industrial de Puerto Rico.

Información General

FIDA funciona como vehículo principal para promover la inversión privada en la agricultura en general, mediante:

· Otras facilidades de crédito financiero con condiciones de repago y tasas de intereses favorables a las empresas agrícolas y agro industriales.

OBJETIVO

· Estimular, incentivar la creación y organizar, capitalizar y financiar las empresas agrícolas.

CAES 6 - Understanding the decline of cocoa production in Trinidad and Tobago. L. Neptune and A. Jacque. Ministry of Agriculture, Land and Marine Resources, Trinidad and Tobago.

Agronomy and Natural Resources (ANR)

Animal Science (ANSC)

Crop Protection (CP)

Forages (FOR)

Food Safety and Value Added Products (FS-VA)

Horticulture (HORT)

Roots and Tubers (R&T)

General Agriculture (GENAG)

Caribbean AgroEconomic Society (CAES)

Agronomy and Natural Resources (ANR)

Animal Sciences (ANSC)

Crop Protection (CP)

Forages (FOR)

Food Safety and Value Added Products (FS-VA)

Horticulture (HORT)

Roots and Tubers (R&T)

General Agriculture (GENAG)

Estado Libre Asociado de Puerto Rico

Misión

Visión

Creación

Información General

OBJETIVO