Caribbean Food Crops Society 44th Annual Meeting July 13th - 17th, 2008  Miami, Florida, USA

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POSTER PRESENTATIONS

Natural Resources

Poster #1

Impact of Coffee Management Practices on the Soil Ecosystem: Earthworm Community Function

J. A. Amador¹, K. Winiarski², D. Sotomayor-Ramirez³.  ¹Laboratory of Soil Ecology and Microbiology and ²Physiological Ecology Laboratory, University of Rhode Island; ³Dept. of Agronomy and Soils, University of Puerto Rico – Mayagüez.  jamador@uri.edu

Coffee (Coffea arabica L.) is the most economically important crop in the central mountainous region of Puerto Rico, where it is grown under shade or in full sunlight. The conditions under which coffee is grown may affect the long-term sustainability of this land use through effects on soil physical, chemical and biological properties. As ecosystem engineers, earthworms are known to have a profound effect on abiotic and biotic properties and processes in terrestrial ecosystems. We examined differences in earthworm communities as a function of ecosystem type (sun and shade coffee, forest) and soil order (Oxisols, Ultisols, Inceptisols) as part of a study of the effects of coffee production practices on the structure and function of coffee agroecosystems led by scientists in the Dept. of Agronomy and Soils of the University of Puerto Rico – Mayagüez. Ecosystem type significantly affected earthworm population density (Sun, 281/m² > Shade, 125/m² > Forest, 37/m²) and earthworm biomass (Sun, 71 g f.w./m² > Shade, 34 g f.w./m² > Forest, 12 g f.w./m²). In contrast, the specific biomass of earthworms was significantly affected only by soil order. In general, earthworm population density and biomass appeared to be a function of soil moisture, leaf litter biomass, and the mineral content of leaf litter. Analyses of ¹⁵N and ¹³C enrichment of earthworm tissues suggest that management practices affect the trophic level they occupy within an ecosystem. Examination of isotopic enrichment of soil and leaf litter is underway to help elucidate the role of earthworms in carbon and nitrogen cycling in these ecosystems.

Keywords: Coffea arabica, cultivation practices, stable isotope enrichment

Poster #2

Heavy Metal Transfer Factors (TF) in Soil-Leaf of Prunus persica L.

D.L. Orihuela¹, J.C. Hernández¹, W. Colón², F. Bastida¹, ¹Escuela Politécnica Superior de La Rábida, Universidad de Huelva, Huelva, España, ²Universidad del Este, Carolina, Puerto Rico.  orihuela@uhu.es

The quantity of an element that the plant is able to absorb from the soil has been object of numerous scientific studies. Transfer Factor (TF) is defined, conceptually, in the scientific literature, as the relation between the concentration either in the plant, or in an organ of a certain element and the concentration of that element in the soil. From a mathematical point of view, this definition would be a deceivingly a simple lineal model. The mathematical models that express the experimental data of the Transfer Factor (TF) are, in general, more complicated, but they always have the remarkable advantage of quantitatively and temporally helping to understand part of the process of soil-to-plant traslocación of the nutritious elements.  We studied the TF of heavy metals in peaches (Prunus persica L.) when the solubility of the soil changes with a process of pH correction. We concluded that the models of transfer of heavy metals (Co, Cu, Ni and Zn) in calcareous soils toward the leaves in the peach tree expressed by the value of TF are in general lineal models. Most of these models of transfer of heavy metals with exceptions of Zn, are also almost horizontal model showing the fact that the concentrations of these elements in leaves are independent of the concentrations in the soil, and that the alterations of the pH of the soil scarcely modify the values of TF.

Keywords: transfers factor, heavy metals, peach, Prunus persica L.

Poster #3

Caracterización del Transporte de Nutrientes y Sedimentos en Suelos Enmendados con Residuos Orgánicos ve Vaquería

G. Ardila¹, D. Sotomayor Ramírez ^1*, G. Martínez ¹ y L. Perez Alegría²

Universidad de Puerto Rico - Recinto de Mayagüez (UPRM), Colegio de Ciencias Agrícolas, Departamento de Agronomía y Suelos, Mayagüez, Puerto Rico; ²Departamento de Ingeniería Agrícola y Biosistemas, UPRM.

*  Autor de contacto:  dsotomayor@uprm.edu

La escorrentía con concentraciones elevadas de nitrógeno (N) y de fósforo (P) proveniente de suelos agrícolas contribuye a la reducción en la calidad de las aguas superficiales.  La disponibilidad ambiental y agronómica de P en suelos puede ser evaluada por medio de un análisis de suelos que sirve de predictor de las concentraciones de P en escorrentía.  Se estudiaron las relaciones entre niveles de P extraíble en suelo, niveles de aplicación de estiércol bovino, y tiempo transcurrido entre la aplicación de la enmienda y la precipitación sobre las concentraciones de N, P y sedimentos en la escorrentía de un suelo de la serie Humatas arcilloso (Typic Haplohumults) bajo la producción de forraje (Brachiaria Decumbens).  Suelos con niveles (Bray1) “bajos” (30 a 90 mg P kg^-1) y “altos” (120 a 200 mg P kg^-1) fueron enmendados con una aplicación baja (15.5 kg N ha^-1 y 5.6 kg P ha^-1) y alta (31 kg N ha^-1 y 11.2 kg P ha^-1) de estiércol bovino y se sometieron a simulaciones de lluvia con intensidad de 70 mm h^-1 para producir 30 minutos de escorrentía.  Las concentraciones de P disuelto, P total, y N total en la escorrentía fueron mayores en los suelos con mayor contenido de P extraíble y con la aplicación alta de estiércol (P<0.05).  No hubieron diferencias significativas en las concentraciones de nutrientes en suelos con “bajo” contenido de P extraíble con la aplicación baja de estiércol y el suelo sin enmienda.  Es de importancia caracterizar el P extraíble que corresponde al grado de saturación de P umbral para predecir adecuadamente el punto cuando las concentraciones de P en escorrentía se incrementarán.  

Palabras clave: escorrentía, fósforo, enmienda orgánica.

Poster #4

Tillage Effects on a Crop Rotation of Yam, Eggplant, Bean And Corn in Oxisol, Ultisol and Vertisol Soils in Puerto Rico
Wanda I. Lugo, Agenol González, Elvin Román, Nydia Rafols and Héctor Lugo. Agricultural Experiment Station, University of Puerto Rico-Mayagüez. wandalugo2001@yahoo.com

The effect of three tillage methods: conventional-till, minimum till and deep till versus no-till and their respective interaction with three fertilizer levels (0, 1x and 2x the recommended amount) were evaluated on a crop rotation that included yam, eggplant, bean and corn.  The experiment was established at three ecologically different locations with three different soil orders: Ultisol, Oxisol and Vertisol soils.  Yam, the first crop in the rotation, was planted after soil preparation according to the treatments.  The crops that followed in the rotation were planted no-till in the same plots.  A fifth treatment, in which all crops in the rotation were planted under conventional tillage, was used as a check.  Yield response of the rotation crops varied with location.  Yam yields in the no-till plots were significantly lower than in the conventional till plots in the Ultisol and Vertisol soils, but not in the Oxisol soil.  Response to fertilizer was observed only in the Oxisol soil.  Yield response of eggplant with respect to the tillage treatments was similar to that observed for yams, suggesting that there was a residual effect of tillage.  For the bean and corn crops, the third and fourth crops of the rotation, the residual effect of the tillage practices performed at the beginning of the rotation cycle was little if any.

Keywords: tillage, crop rotation, conservation tillage

FRUITS, VEGETABLES, AND SPECIALTY CROPS

Poster #5

Respuesta de Líneas de Habichuela (Phaseolus vulgaris L.) a Diferentes Niveles  de Fertilidad en un Oxisol

R. Dorcinvil ¹, D. Sotomayor Ramírez ^1*, and J. Beaver ¹,

Universidad de Puerto Rico - Recinto de Mayagüez, Colegio de Ciencias Agrícolas, Departamento de Agronomía y Suelos, Mayagüez, Puerto Rico

* Autor de contacto:  dsotomayor@uprm.edu

La baja disponibilidad de fósforo (P) y de nitrógeno (N), seguido por factores de acidez del suelo como exceso de aluminio (Al) y de manganeso (Mn) constituyen las limitaciones más importantes para la producción de habichuela (Phaseolus vulgaris L.) en el trópico. El desarrollo de genotipos adaptados a estas condiciones es una estrategia económica y ecológicamente viable para enfrentar el problema.  Se realizaron dos experimentos para identificar líneas de habichuela adaptadas a condiciones de baja fertilidad en un Oxisol de Puerto Rico. En el primer experimento, 6 líneas hermanas de habichuela (3 con sistema radicular superficial y 3 con sistema radicular profundo) y 9 combinaciones de mezclas de semillas fueron sembradas bajo dos niveles de fertilidad (sin fertilizante y aplicación de 50 kg/ha de N, P₂O₅, K₂O respectivamente). En el segundo experimento, 38 líneas mayoritariamente de grano rojo y negro provenientes de una selección previa de 228 líneas del programa de mejoramiento de la Escuela Agrícola Panamericana de Honduras denominado Vivero de Adaptación Centroamericano (VIDAC) fueron evaluadas bajo 3 regímenes de fertilización: (i) 50 kg N/ha, 57 kg P₂O₅/ha (+N+P); (ii) 0 kg N/ha, 57 kg P₂O₅/ha (-N+P); y (iii)  50 kg N/ha, 0 kg P₂O₅/ha (+N-P); todas las parcelas recibieron 54 kg K₂O/ha.  Las líneas con sistema radicular superficial y mixto obtuvieron mayores rendimientos y mayores concentraciones de N y de P que las líneas con sistema radicular profundo en las parcelas de baja fertilidad.  Las líneas con un sistema radicular superficial y extenso como VAX 3 y las líneas RBF tuvieron rendimientos similares independiente del régimen de fertilidad.  Los rendimientos en las lineas con un sistema radicular profundo como SER 16 y las XRAV tuvieron rendimientos en el orden de +N+P > +N-P > -N+P.  La arquitectura de la raíz es una adaptación genotípica de la habichuela para la adquisición de N y de P.

Palabras clave: Fertilidad de suelos, Habichuelas, Adaptación genotípica

Poster #6

Response of Taro var. Lila or Bun Long to Levels of Supplemental Irrigation

Luis E. Rivera ¹, Carlos E. Ortíz¹  and John J. Cho ² ; ¹ Department of Agronomy & Soils, University of Puerto Rico, Mayagüez Campus;  ² Department of Plant Pathology, University of Hawaii. cOrtíz@uprm.edu

Production of taro (Colocasia esculenta) throughout the Caribbean Basin has been drastically reduced as a consequence of the taro leaf blight (Phytophthora colocasiae). Blight tolerant varieties developed in Hawaii and currently under evaluation in Puerto Rico, appear not to have the culinary characteristics preferred by consumers in the Caribbean. Thus, there is considerable interest in the production of the traditional taro variety ‘Lila’ (known in Hawaii as ‘Bun Long’) under drip irrigation, a system under which blight incidence tends to be lower. A study was conducted to estimate growth and yield of taro variety ‘Lila’ planted under upland conditions and with three levels of irrigation. Irrigation treatments were: rainfed and supplemental irrigation based upon Class A pan factors of 1.0 and 1.3. Taro leaf blight was present throughout the crop cycle. Results showed significant effects of irrigation on plant growth. Harvest index was relatively low for all treatments. Tubers of variety ‘Lila’ grown under upland conditions and under the presence of the blight were acceptable for marketing.

Keywords:  taro, irrigation, leaf blight

Poster #7

Production of Table Cucumber on Two Trellis Systems in North Florida.

C. S. Gardner, G.L. Queeley, K. Grant and B Brown, Cooperative Extension Program Florida Agricultural and Mechanical University(FAMU)   College Of Engineering Sciences Technology and Agriculture  202 Perry – Paige Building South, Tallahassee, FL 32307. cassel.gardner@famu.edu

Use of trellis to support vine crops such as tomato, squash and cucumber may result in increased fruit yields and quality compared to conventional practice of allowing the vines to run freely on the ground surface. Advantages of the trellis system include less fruit spoilage, better canopy light interception, better control of insect and diseases (more uniform coverage of fruits and leaves) and ease of harvesting. However, opponents of the trellis method claim that the light intercepted by trellis grown crops does not result in significant yield difference compared to conventional practice and that the latter practice expose fruits to easy damage by birds, insects and other organisms.  The objective of this study was to determine the performance of trellis grown cucumber vs. conventional practice. The study was done at FAMU research/ extension farm, Quincy Florida. Treatments were ‘A’ frame trellis, wire trellis and conventional practice as control. Design was RCB. Seeding was done on 6/26 on raised beds on 6 ft center spaced 3 ft apart within row. Each row had 24 plants and constituted a plot. Drip irrigation was applied as needed. Harvest was from 8/15 – 8/29. Parameters measured were fruit size (length and circumference), time to peak harvest, fruit quality and total yield (# of good fruits and weight). Statistical analysis was done using SAS GLM procedure. Results showed no significant difference (P< 0.05) for any of the measured parameters although the control had the most spoiled fruits. Despite no differences the trellis method may better suit older home gardeners who may suffer from back problems. This study is being repeated to better validate these findings.

Keywords: trellis system, vine crops, fruit quality.

Poster #8

Effects of bulbils weight used as seed on tuber yield of greater yam belep (dioscorea alata l.)

David Hammouya, Marceau Farant, J. Lator and J. L. Irep. INRA, Unité expérimentale de Duclos Godet, Cluny, 97131, Petit-Canal, Guadeloupe. david.hammouya@antilles.inra.fr

Traditionally, yams are grown from tuber cuttings, termed setts. Aerial tubers named bulbils could constitute, for some species, an alternative way to produce yam seeds in order to benefit safe seed and more earnings of harvested tubers.

Work reported in this paper comes from experimentation conducted during two years on effects of bulbil weight on tuber yield. An experiment was carried out on vertisols at Godet experimentental station in Guadeloupe. Four bulbil classes of weight were combined and some of the results obtained are presented in this paper.

Bulbil weight strongly affected the yield, whereas the effect on tuber number was not significant for the commercial tuber yield and the number of non commercial tubers. Commercial tuber yield tended to increase asymptotically with increasing bulbil weight. 

Keywords: yam, bulbils, seed, setts

Poster #9

Performance of a Quality Protein Maize Variety Grown in a Vertisol

Elvin Román-Paoli¹, and James Beaver², ¹Professor, Department of Agronomy y Soils, College of Agricultural Science, University of Puerto Rico. HC-O2 BZ 11656, Lajas, PR 00667-9714. Tel.(787) 899-1530, Fax (787) 899-1265, eroman@uprm.edu. ²Professor, Department of Agronomy y Soils, College of Agricultural Science, University of Puerto Rico. Mayagüez, PR

Almost all of the maize consumed in Puerto Rico (PR) is imported. The artificial scarcity of maize due to its destination for ethanol production has contributed to a worldwide price increase.  Quality protein maize (QPM) are hard-endosperm maize developed by the ¨Centro Internacional de Mejoramiento de Maíz y Trigo¨ (CIMMYT).  QPM has the recessive opaque-2 gene that contains higher lysine and tryptophan content than common maize.  The objective of this research is to develop appropriate management practices for the production of QPM in PR. Field trials were conducted at the Lajas Substations to evaluate the performance of a QPM variety. During 2007, a QPM variety was submitted to three nitrogen fertilization rates (120, 160, 200 kg/ha) split in two applications.  Plants were also fertilized with 50 and 100 kg/ha of P₂O₅ and K₂O, respectively. Final plant density was 36,580 plants/ha.  No significant differences were found among N rates with an average yield of 2,770 kg/ha.  A split-plot arrangement of a Randomized Complete Block Design was used in an experiment established during 2008 where levels of microirrigation treatments were the whole-plots and plant density the sub-plots. Whole plot treatments consisted of 100, 75 and 50% ET₀ applied through drip irrigation.  The sub-plot treatment consisted of 50,000, 62,000 and 71,400 plants/ha.  The results obtained in this research will be shared with swine producers and farmers who may be interested in producing QPM to partially substitute maize imports in PR.  

Keywords: Maize, yield, Quality Protein Maize 

Poster #10

Effects of Plastic Mulch on Development and Nodulation of Cowpeas

Steven H. Wysinger, E. G. Rhoden, V. Khan, C. Stevens and J. R. Bartlett. George Washington Carver Agricultural Experiment Station, Tuskegee University, Tuskegee, AL 36088. rhoden@tuskegee.edu

Cowpeas or Southern peas (Vigna unguiculata L. Walp) are a warm season crop and its growth and development are impacted by various soil and environmental conditions. Cowpea is an important crop in the southeastern United States for both animal and human consumption. It contains approximately 24.8% protein, 63.6% carbohydrate and many trace minerals. When cowpeas are intercropped it provides nitrogen to its companion crops thereby reducing the need for mineral nitrogen. Due to advances in plasticulture many warm season crops are able to be planted earlier without significant yield losses. Despite these advances very little is known about the effects of plastic mulch in cowpea production. This study was conducted to compare the effects of white and black plastic mulches as opposed to bare soil in terms of cowpea development and nodulation. The experiment was conducted as a complete randomized design consisted of three treatments (white and black plastic with bare soil as the control) planted on a 150’ rows. Plant height was monitored throughout the study while nodule number and weights were taken at the 10% bloom stage.  Cowpeas yield comprised of three harvests (once per week for 3 weeks) There were no significant difference in the yield between white (WP) and black plastic (BP) but these were significantly higher than bare soil (BS). In terms of nodulation, WP treatment had the highest nodule weight followed by BS; on the other hand, BP had numerous small nodules.  Further evaluations are being conducted to quantify the differences in soil temperature, solar reflectance and microbial activities in the soil that might explain some of the differences observed in the various treatments.

Keywords: plastic mulch, cowpea, nodulation, legume development

Poster #11

The Effect of Lime Application on Emergence and Growth of Castor Oil Plants

Ronald J. Smith, E. G. Rhoden, J. R. Bartlett, V.A. Khan, C. Drakes and P. K. Biswas.  George Washington Carver Agricultural Experiment Station, Tuskegee University, Tuskegee, AL36088. rhoden@tuskegee.edu

Castor oil (Ricinus communis) has been cultivated for centuries and its production is currently being scrutinized because of the ricin content of the plant and its possible use in terrorist activities.  The objective of this study was to measure the effects of lime application on the emergence, growth and development of castor accessions under greenhouse conditions.  Lime was applied to a Norfolk Sandy loam soil and incubated for three months.  Castor oil seeds were planted into a soil with a pH of either 5.3 or 5.9. The five accessions used in the study were obtained from: Tanzania (TZ1, TZ2), Guyana (GY-PAR), and Jamaica (JA2, JA4).  The study was conducted in the greenhouse facilities at the G. W. Carver Agricultural Experiment Station at Tuskegee University. Data were collected on plant emergence, height, and vigor, as well as dry matter yield. Four weeks after emergence, TZ2 and GY-PAR had the highest percent germination (96%), while JA2 exhibited the lowest (80%) when limed.  One week later, the highest percent germination remained the same, and JA2 had the lowest percent germination (88%).  When soil was left unlimed (pH 5.3) TZ1 had the highest percent germination (88%), while only 76 % of JA4 seeds had germinated.  One week later, TZ1 remained the same, and all other accessions exhibited 80% germination.  At 4 weeks only JA2 plants showed increased foliage production when limed.  However, 8 weeks after emergence, JA2 and JA4 produced more foliage when limed.  After 8 weeks, the results also indicated that plants that were limed had higher dry weights (66.1 g/pot) than unlimed plants (63.3 g/pot). At 12 weeks only JA2 had increased foliage production under limed conditions.  It is possible that both the Tanzania and the Guyana accessions produced more dry matter at 4 and 8 weeks, when no lime was applied, because the soil types in both locations were predominantly acid.  On the other hand, the Jamaican accessions give higher dry weights under limed conditions because they were taken from soils that were calcareous.  Further studies are needed to identify accessions that are suitable for the southern US.

Keywords: castor, germination, accession

FRUITS, VEGETABLES, AND SPECIALTY CROPS

Poster #12

Mandarina Híbrida Fallglo: Primeros Cuatro Años de Crecimiento en Dos Localidades de Puerto Rico

Félix M. Román Pérez, Agenol González Vélez y Raúl Macchiavelli, Catedráticos, Colegio de Ciencias Agrícolas, Estación Experimental Agrícola, Universidad de Puerto Rico, Recinto Universitario de Mayagüez, fmroman@uprm.edu

La mandarina híbrida Fallglo, Bower (C. reticulata x tangelo Orlando) x Temple (C. reticulata híbrida) liberada por el USDA en el 1987 está siendo evaluada en las localidades de Isabela y Corozal en la isla de Puerto Rico.  La primera localidad es representativa de la zona costera (124 msnm) y la segunda de la zona intermedia central (200 msnm), con temperatura promedio anual de 77 y 76 ⁰F, respectivamente.  Los primeros cuatro años se observó el desarrollo y comportamiento hortícola de los árboles en las dos zonas.  El primer año de producción comercial, correspondiente al cuarto año de crecimiento, las primeras frutas comenzaron a madurar en el mes de septiembre en Isabela, mientras que en Corozal comenzaron a madurar en octubre.  La variedad fue injertada en los patrones Swingle citrumelo (Citrus paradisi x Poncirus trifoliata), el híbrido HRS 812 [mandarina Sunki (C. reticulata) x naranja trifoliada Benecke (P. trifoliata)], Carrizo (Citrus sinensis x P. trifoliata), y las mandarinas Cleopatra (Citrus reticulata Blanco) y Sun Chu Sha. Durante la primera cosecha se tomaron los siguientes datos: promedio de número de frutas por árbol, peso total y peso promedio por fruta, diámetro, altura y diámetro de copa de los árboles y volumen de copa.  Los resultados de la primera cosecha muestran que los patrones produjeron significativamente mayor cantidad de frutas por árbol en la localidad de Corozal (235.2) que en la localidad de Isabela (92.8).  Para la variable peso promedio de frutas por árbol los valores obtenidos para la comparación entre localidades se acercaron a la significancia (p=0.0678), indicando una tendencia a ser mayor en la localidad de Corozal que en Isabela, 48.6 kg y 29.1 kg, respectivamente. En ambas localidades no se detectaron diferencias significativas entre los distintos patrones para ninguno de los parámetros medidos.  En ambas localidades, algunos árboles fueron afectados por una muerte descendente en algunas ramas, siendo la misma de origen desconocido.  Síntomas muy similares a estos han sido reportados en la literatura.

Palabras clave: cítricos, patrones, crecimiento, variedad

Poster #13

Yield and Fruit Quality of Rambutan Cultivars Grown at Two Locations in Puerto Rico

R. Goenaga¹ and A. Marrero¹. ¹USDA-ARS, Tropical Agriculture Research Station, 2200 P. A. Campos Ave., Suite 201, Mayagüez, Puerto Rico 00680-5470. Ricardo.Goenaga@ars.usda.gov

Eight rambutan (Nephelium lappaceum) cultivars grown on an Oxisol and Ultisol were evaluated for three years under intensive management at Isabela and Corozal, Puerto Rico, respectively.  There were significant differences in number and weight of fruits per hectare between locations and years. Significantly more fruits were produced at Corozal (357,004 fruits/ha) than at Isabela (168,083 fruits/ha).  Fruit yield at Corozal and Isabela was 11,357 and 5,111 kg/ha, respectively.  At Corozal, varieties were not significantly different for number of fruit and yield per hectare.  At Isabela, cultivar Gula Batus and R-162 produced significantly more fruits and higher fruit weight than other cultivars averaging 234,153 fruits/ha and 6,979 kg/ha, respectively.  Cultivar R-156Y had the lowest yield at both locations.  Cultivars R-156Y and Rongrien had fruit with significantly more pulp (58%) than other cultivars (47%).  At both locations, significantly lower fruit soluble solids (Brix) values (19.1) were obtained from fruits of cultivars R-156Y and Gula Batus; there were no significant differences in Brix among the rest of the cultivars (20.2).

Keywords: tropical fruits, rambutan, adaptability, soluble solids

Poster #14

Calibration of SPAD-meter Readings to Chlorophyll Content in Strawberry

D.L. Orihuela¹, W. Colón², J.C. Hernández¹, C. Weiland¹,

¹Escuela Politécnica Superior de La Rábida, Universidad de Huelva, Huelva, España, ²Universidad del Este, Carolina, Puerto Rico, orihuela@uhu.es

The relationship between SPAD-meter readings to Chlorophyll content vary according to the crop sampled, crop vegetative stage, fertilization regimes, water stress, and other environmental factors.  The objective of this research was to calibrate the Minolta SPAD 502 readings to chlorophyll content in strawberry (Fragaria x ananasa Duch.). Once the meter was calibrated, the model was compared to other crops and with other models. Leaf chlorophyll content was determined by the acetone extraction and spectrophotometer method.  Greenhouse grown plants were exposed to 27 fertilization treatments of different levels of N-P-K with 5 replications. To obtain the best fit, linear, logarithmic, cubic, and exponential models were tested between SPAD readings and leaf chlorophyll content.  The linear model equation resulted in the best fit and the relationship was µg chlorophyll/g leaf = 0.0116 SPAD reading – 0.1457.

Keywords: SPAD-meter, chlorophyll, strawberry

Poster #15

Growth Rate and Yield of Coffee (Coffea arabica L.) Grown Under Partial Shade and Full Sunlight after Severe Renovation Pruning

Carlos A Flores Ortega¹, and Miguel A. Muñoz². ¹Horticulture Department, ²Agronomy and Soils Department, Agricultural Experiment Station, University of Puerto Rico, Mayagüez Campus. agro_flores@yahoo.com

Severe renovation pruning of old coffee trees is an alternative to renovate old plantations.  The success of success after implementing severe pruning may vary depending if coffee is grown under partial shade or full sunlight. It has been suggested that permanent partial shade creates a better environment for coffee renovation after severe pruning and that the crop can withstand better drought periods; it will benefit from reduced evapotranspiration; reduced wind and sun damage on new leaves and the fruit size is improved. This paper presents the results of a series of experiments on agroforestry planting systems on coffee plantations, comparing the recuperation of a severe pruned plantation under full sunlight and under shade conditions. The study was conducted for five years in the Agricultural Experimental Station at Adjuntas, located in the central region of the island. Two coffee plots of Puerto Rico 401 variety planted under partial shade of Pithecellobium carbonarium were used for the study. The shade was eliminated in one plot and both plots were submitted to severe renovation pruning. A factorial design was used for the study where the main plot was the treatment (partial shade and Full sun), years as subplot and 12 repetitions (trees). Data was collected on foliage development, canopy volume, harvesting, mortality and coffee quality. Climatic data on sunlight intensity, and air and soil temperature was also collected. Three methods to estimate canopy volume were evaluated.  Significant differences (p<=0.05) on tree height was found. Average tree’s height under partial shade was 1.68 m during 2004, 3.09 m during 2006 and 4.12 m during 2008 while full sun trees reached 1.34 m during 2004, 2.59 m during 2006 and 3.42 m during 2008.   Canopy volume (CV) estimated by the CVF3 was the more precise among the three formulas tested. CV for full sun trees was estimated on 17.64 m while the shaded trees CV was estimated in 28.49 m, with a DMS=7.92125. Also mortality observed was three times higher at full sun treatment than at partial shade.

Keywords:  coffee, pruning, agroforestry.

Poster #16

Reducing the time in nursery for ‘Marsh’ and ‘Duncan’ grapefruits with a Commercial Amino Acid Mixture and a Commercial Ascophyllum Kelp Extract

J. Pablo Morales-Payán. Department of Horticulture, University of Puerto Rico, Mayagüez Campus. jpmorales@uprm.edu; josepablomorales@yahoo.com

Experiments were conducted in Mayagüez, Puerto Rico, to determine the effect of two biostimulants on the in-nursery growth of grapefruit budded on ‘Cleopatra’ rootstock. A kelp (Ascophyllum nodosum) extract (Stimplex®) and a commercial mixture of amino acids (Macro-Sorb Radicular®) were drenched at several rates, starting one month after budding and repeating the applications every 10 days until the plants reached the adequate transplanting stage. Biostimulant-treated plants attained the adequate transplanting stage earlier than untreated plants. ‘Duncan’ and ‘Marsh’ responded equally to the biostimulants, and the extent of growth response was greater as the biostimulant rates increased. These results indicate that both biostimulants may be useful to accelerate the production of ‘Duncan’ and ‘Marsh’ grapefruits budded on ‘Cleopatra’ rootstock.

Keywords: biostimulants; growth regulators; physiological regulators.

Poster #17

Organic Watermelon Yield is Affected by Alternative Pesticides and Mulching

Mabel Vega-Almodovar, J. Pablo Morales-Payán, Sonia Martínez-Garrastazú and  Bryan Brunner

Department of Horticulture, University of Puerto Rico, Mayagüez Campus. jpmorales@uprm.edu

There is a growing interest in organic horticulture in Puerto Rico. One of the main limitations for organic production is the scarcity of recommendations based on local research. Mulching for weed suppression and alternative pesticides for disease management in an organic watermelon system were tested in field experiments in Lajas, Puerto Rico. Plots were either mulched with freshly-cut grass straw or not mulched. The alternative pesticides were commercial formulations of a garlic extract (Garlic Barrier®), a neem extract (Trylogy®), potassium bicarbonate (Milstop®), hydrogen dioxide (Oxidate®), a Melaleuca alternifolia oil extract (Timorex®), a rosemary oil (Ecotrol®), a blend of rosemary and wintergreen essential oils (Sporan®), Bacillus pumilis strain QST 2808 (Sonata®), B. subtilis strain QST 713 (Serenade®), B. thuringiensis (Javelin®) mixed with copper fungicide (NuCop®) alternated with B. thuringiensis (Agree®) mixed with copper fungicide (NuCop®), whole milk, and water (as a non-treated check). Organic pesticides were applied weekly at recommended rates. The prevalent weed during the first half of the crop season was purple nutsedge (Cyperus rotundus), with grasses and Ipomoea spp. becoming more common in the later stages of the crop. Downy mildew was the prevalent disease throughout the season. Watermelon yield was significantly higher in mulched plots than in non-mulched plots, due to weed suppression by the mulch. Among the organic pesticide treatments resulting in the highest crop yields were hydrogen dioxide, Bacillus pumilis strain QST 2808, the garlic extract, and the Melaleuca alternifolia oil extract. These results provide valuable information for weed and disease management in organic and ecological watermelon systems in tropical regions.

Keywords:  Ecological pesticides; Cyperus rotundus, downy mildew.

Poster #18

Crecimientos Vegetativo y Reproductivo del Aguacate ‘Hass’ en Varios Climas de Michoacán, México

J.L. Rocha-Arroyo, S. Salazar-García, I.J.L. González-Durán y J. Anguiano-Contreras. INIFAP-Campo Experimental Uruapan, Uruapan, Michoacán. México. E-mail: samuelsalazar@prodigy.net.mx

En Michoacán se cultivan más de 96 mil ha de aguacate ‘Hass’ pero existe poca información para entender su comportamiento fenológico en los diferentes climas. El objetivo del estudio fue cuantificar la influencia del clima sobre la ocurrencia e intensidad de los flujos vegetativos (FV) y su importancia para la floración. Se seleccionaron 14 huertos adultos de ‘Hass’ distribuidos en siete climas. En cada huerto se eligieron 10 árboles y en cada uno de ellos se marcaron cinco ramas de 1-1.5 m de longitud; en cada rama se etiquetaron 15-20 brotes del FV de invierno para darle seguimiento a cada brote. Los brotes vegetativos producidos por cada FV fueron etiquetados para determinar el  tipo de crecimiento producido (vegetativo, floral o inactivo) durante 2006-2008. En todos los climas hubo tres FV (invierno, primavera y verano) y cuatro flujos de floración: “Loca” (Ago-Sep), “Aventajada” (Oct-Dic), “Normal” (Dic-Feb), y “Marceña” (Feb-Mar). El clima influenció (P = 0.05) la intensidad de floración producida por los brotes originados en los tres FV’s. La floración Normal fue la más abundante en los tres FV’s y en la mayoría de los climas. El FV de invierno fue el más importante para la producción de cualquier flujo de floración. Para el FV invierno, la mayor intensidad de las floraciones Loca y Aventajada ocurrió en climas Semicálido subhúmedo (SS) y Templado húmedo (TH). En brotes de los FV’s primavera y verano estas floraciones fueron más intensas en los climas SS, Semicálido húmedo (SH), Templado subhúmedo (TS) y TH. La mayor intensidad de floración Normal ocurrió en los climas SH y TH (brotes de invierno), Cálido subhúmedo (CS) (brotes de primavera), y en climas SS, SH y TH (brotes de verano). Para los tres FV’s, la floración Marceña fue más intensa en los climas CS y SS. En cualquier FV la floración Normal tendió a ser más intensa en los climas fríos (SH, TS y TH), mientras que la Marceña se incrementó en los climas cálidos (CS y SS).

Palabras clave: Persea americana, floración, fenología.

Poster #19

Corrección de la Deficiencia Crónica de Zinc en Aguacate ‘Hass’

S. Salazar-García¹, L.E. Cossio-Vargas² y I.J.L. González-Durán¹, ¹INIFAP-Campo Experimental Santiago Ixcuintla, Nayarit, México. ²Universidad Autónoma de Nayarit, Posgrado en Ciencias Biológico Agropecuarias. Xalisco, Nayarit, México. E-mail: samuelsalazar@prodigy.net.mx

En los huertos de aguacate ‘Hass’ de los municipios de Tepic y Xalisco, Nayarit, son frecuentes los niveles foliares debajo de lo normal de zinc (Zn) y la presencia de síntomas visuales de deficiencia de Zn en hojas, brotes y frutos. Esta investigación se desarrolló del 2001 al 2005 en dos huertos comerciales de aguacate ‘Hass’ cultivados sin riego en el  Mpio. de Tepic con el objetivo de evaluar el efecto de las aplicaciones de sulfato de zinc (ZnSO₄), al follaje o al suelo, sobre la producción, tamaño y forma del fruto. El suelo de los huertos era de textura ligera, pH 5.8 y bajo contenido de Zn (1.4 a 3.13 mg×kg^-1). Los tratamientos al follaje fueron aplicados en 8 L agua/árbol y consistieron en: a) una aspersión con 4.056 g ZnSO₄/L agua (1.46 g Zn), y b) dos aspersiones con 2.028 g ZnSO₄/L agua (0.73 g Zn); ambos tratamientos proporcionaron 11.68 g Zn/árbol. Los tratamientos al suelo consistieron en: a) una aplicación (1.5 kg), y b) dos aplicaciones (0.75 kg c/u) anuales de ZnSO₄ (35.5% Zn) al suelo. El tratamiento Control no recibió Zn. Las aspersiones foliares con ZnSO₄ no afectaron la producción y tamaño del fruto. El promedio de las cosechas 2003, 2004 y 2005 mostró que dos aplicaciones al suelo con 0.75 kg ZnSO₄/árbol/año resultaron en la mayor producción total de fruto (173 kg/árbol), producción de fruto grande (170 a >266 g/fruto; 109 kg/árbol), y la relación largo-ancho del fruto (1.9), comparado con los árboles Control, que tuvieron menor producción total (136.7 kg/árbol), menor producción de fruto grande (59.2 kg/árbol), y forma  más redonda del fruto (rel. largo-ancho = 1.36). La aplicación anual de 1.5 kg ZnSO₄/árbol mostró valores significativamente inferiores a dos aplicaciones anuales de 0.75 kg c/u, pero significativamente superiores al Control. Se encontró una pobre relación entre los niveles de ZnSO₄ aplicados al suelo y el contenido foliar de Zn.

Palabras clave: Persea americana, producción, deficiencias nutrimentales

Poster #20

Papaya Growth in Double-Row Systems Established During the Dry Season

Thomas W. Zimmerman, University of the Virgin Islands Agricultural Experiment Station, RR 1 Box 10,000, Kingshill, VI 00850.  Email: tzimmer@uvi.edu

Papaya is an important fruit in the tropics due to its nutritional level and year round production.  Papaya production in the Virgin Islands is hindered by the lengthy dry season in this semi arid environment where fresh water is lacking.  Three selected papaya varieties, ‘Maradol’, ‘Tainung 5’ and ‘Yuen Nong 1’ were grown in 1m x 1 m, 1m x 2 m or 1m x 3m double-row spacing regime randomized block design incorporating drip irrigation with 4L/hr emitters at 1 m intervals and grass-hay mulch.  The objective was to determine water usage, plant growth and fruit set during the first six months establishment in the dry season of the U.S. Virgin Islands.  Tensiometers set at 30 cm depth were used to determine when water was applied and indicated that the 1 x 1 m double row depleted the water quicker than the other two spacing regimes.  Data collected included: rainfall, irrigation water applied, plant height, height to first flower, stem diameter at 1 m and number of fruit set after six months.  Plants grown in the 1 x 1 m double row were taller, had thinner stems and significantly fewer fruit set for all varieties during the six months of plant establishment and growth.  The 1 x 2 m double row grown papaya were similar to the 1 x 3 m double row plants for height, stem diameter and fruit set.  The 1 x 2 m double row growing system is recommended to increase production where space and water are limiting factors. A grass/hay mulch is very effective in controlling weeds, conserving soil moisture and protecting the soil from erosion during sudden short heavy tropical rains.

Keywords: grass-hay mulch, ‘Maradol’, ‘Tainung 5’, ‘Yuen Nong 1’, stem diameter, fruit set

SOCIOECONOMICS AND POLICY

Poster #21

Agricultural Labor Issues and Immigration in Southwest Florida:

Robert D. Halman, University of Florida IFAS Extension – Collier County, 14700 Immokalee Road, Naples FL 34120.  rdhalman@ufl.edu

Southwest Florida is a major agricultural area on the Florida Gulf Coast. The sub-tropical climate of many of the counties makes the region ideal for the production of diversified agricultural crops. A large migrant labor force is responsible for land preparation, planting, harvesting and processing of the fruits and vegetables grown in the region. The recent stepped up activities of the U.S. Immigration and Customs Enforcement (ICE) responsible for investigating a wide range of domestic and international activities arising from the illegal movement of people and goods into, within, and out of the United States has been critical in labor availability. The region, as an excellent recreational, tourist and residential destination, has caused another labor dynamic in the landscape industry. These transitional labor issues as well as local law enforcement involvement will be presented.

Keywords:  Migrant, Immigration and Customs Enforcement (ICE), Labor

Poster #22

PROCINORTE’S Tropical and Subtropical Fruits Task Force: a Tri-National Effort to Improve Fruit Quality and Trade

R. Goenaga¹, S. Salazar-García², G. Doyon³, J.A. Osuna-García², I.J.L. González-Durán ² and J.A. Landry⁴.  ¹USDA-ARS, Tropical Agriculture Research Station, 2200 P. A. Campos Ave., Suite 201, Mayagüez, Puerto Rico 00680-5470 (Ricardo.Goenaga@ars.usda.gov); ²INIFAP-Campo Experimental Santiago Ixcuintla, Apdo. Postal 100, Santiago Ixcuintla, Nayarit, Mexico 63300; ³Food Research and Development Centre, Agriculture and Agri-Food Canada, 3600 Casavant Blvd. West, St. Hyacinthe, Quebéc, Canada J2S 8E3; ⁴University of Quebéc, 1100 Notre Dame W. St., Quebéc, Canada H3C 1K3 

Canada, Mexico and United States are countries that share many interests in agricultural affairs. The three countries have been commercial partners for many years, and most recently they have been working under the North American Free Trade Agreement (NAFTA) umbrella.  The three countries are natural commercial partners sharing several common problems in agriculture. Some of these problems are related to food safety and quality, control of pests and diseases, and other issues concerning food exports and imports.  One very important mechanism to facilitate the institutional and technical integration of Canada, United States and Mexico is PROCINORTE under the umbrella of the Inter American Institute for Cooperation on Agriculture's (IICA), Northern Regional Center.  PROCINORTE is a cooperative Program in Research and Technology for the Northern Region, with an Umbrella Task Force that determines common research priorities.  Within PROCINORTE, several initiatives or task forces have been formed.  The Tropical and Subtropical Fruits Task Force was established in 2002.  The main goal of this task force is to improve production, consumption and trade of tropical and subtropical fruits in the entire PROCINORTE region. Specific objectives are to: 1) encourage the communications and collaboration among scientists working in quality, safety, and production of tropical and subtropical fruits; and 2) identification of common problems and opportunities associated with tropical fruit production and quality and work jointly in research projects to solve these.  A summary of activities carried out by the Tropical and Subtropical Fruits Task Force is presented here.

Keywords: commerce, exportation, food safety.

Poster #23

Le Programme Régional de Développement Agricole : un outil méthodologique pour la modernisation et l’adaptation de l’agriculture Guadeloupéenne.

Edmond Rubrice, Chambre d’agriculture de Guadeloupe, Guadeloupe. rubrice.cda@wanadoo.fr

Après la réforme du financement du développement agricole et rural en France, le Ministère de l’agriculture et de la Pêche signait avec l’APCA en 2004 un premier contrat d’objectifs pour les programmes de développement agricole des chambres d’agriculture.  Ce contrat commun à toutes les chambres régionales d’agriculture de France a représenté un changement méthodologique important et a amélioré la lisibilité des actions à partir de six objectifs : Accompagner les mutations des exploitations agricoles ; adapter les productions et les activités aux attentes des marchés ; gérer et préserver les ressources en eau ; participer au développement territorial ; piloter les actions en cohérence avec les autres politiques publiques.

En Guadeloupe, en complément du conseil technique individualisé, le Programme Régional de Développement Agricole a favorisé la réalisation des actions d’intérêt général et l’accompagnement des agriculteurs au changement des politiques agricoles et rurales : Organisation des filières de diversification ; nouvelles méthodes de collecte des données pour le réseau de suivi, les références systèmes et technico-économiques ; observatoire économique et social ; agro transformation ; agritourisme et animation du réseau « bienvenue à la ferme » ; sensibilisation sur les enjeux de l’agri-environnement ; partenariat avec les acteurs du système recherche développement formation ; amélioration de la gouvernance du projet.

La valorisation des acquis méthodologiques se poursuivra dans le cadre d’un second contrat d’objectifs 2009-2013.  Il permettra de préparer l’avenir de l’agriculture guadeloupéenne sur les bases de quatre nouvelles priorités et en fonction des attentes de la société : satisfaire les marchés par des productions adaptées ; relever les défis environnementaux par des modes de production innovants et durables ; contribuer au développement durable des territoires par des activités et des systèmes d’exploitations adaptés ; innover dans l’exercice des métiers par des entreprises agricoles performantes avec des actifs professionnels responsables et organisés.

Mots clés : contrat d’objectifs, agriculture durable, Guadeloupe.

Poster #24

Incubator Farms as a Sustainable Approach for ‘Neo Farmers’
Puran Bridgemohan, Centre  Biosciences, Agriculture, and Food Technology, University of Trinidad and Tobago, Point Lisas Campus. puran.bridgemohan@utt.edu.tt

Trinidad and Tobago is facing a challenge of urban migration and a reduction in an already ageing farming population. There is an urgent need
to attract new and emerging farmers to this vocation and guide them to be economically viable and educated farmers of the future. Incubator Farm is
a unique and successfully proven approach which will be appropriate for Small Island States Economies, and will assist to educate aspiring
farmers and establish their business as incubators. This paper discusses the creation of a more closed-loop food system through the establishment
of several farms for the production of dwarf pommecythere, cassava, and hot peppers linked to a post –harvest facilities and multi-purpose pilot
processing plant.
Keywords: incubator farm, dwarf pommecythere, cassava, and hot peppers

Poster #25

Policy Implications of the Composite CARICOM Business Environment

Ronald M. Gordon and John J. VanSickle. Food and Resource Economics Department, University of Florida, 1197 McCarty Hal, PO Box 110240, Gainesville, FL 32611-0240. rmg251@yahoo.com.

Comprehensive data and information on the characteristics of the business environment of CARICOM countries are limited, likely constraining informed policy formulation. This research project sought to characterize the CARICOM business environment by interviewing and surveying representatives of firms from the countries of Dominica, Guyana, Jamaica, St. Lucia and Trinidad and Tobago.

The business environment was revealed to be heterogeneous and multi-faceted with important differences pertaining to firm size, area of operation and geographical scope. The proportion of micro firms with an annual sales volume (ASV) of less than US dollars1.0 million exceeded twice that of large firms with an ASV in excess of US dollars 6.5 million. The proportion of small firms with an ASV between US dollars 1.0 million and US dollars 2.5 million is similar to that of  medium firms with an ASV between US dollars 2.5 million and US dollars 6.5 million. Some firms operated only in one sector. Others, across the firm-size groups, reported multi-sectoral operations with combinations such as agriculture and manufacturing; agriculture, manufacturing and services; manufacturing with trade and commerce; and agriculture and professional services. Some firms’ geographical scope of operations also transcended the firm-size groups, with micro and large firms among those indicating global operations. Respondents viewed CARICOM positively but entrepreneurs thought CARICOM did not strengthen their business environment.

These findings suggest that CARICOM policy formulation should be more cognizant of the distinctiveness of the business environment, exhibited by the major sub-groups of firms across the countries. The policy strategy should also actively and deliberately embrace the economic and related characteristics exhibited by countries, firms and sub-sectors within the business environment.

Keywords: CARICOM countries; Caribbean business environment; policy formulation.

Poster #26

An Evaluation of Dairy Farming in Suriname

Samantha Engeldal, Dept. of Agriculture, Anton de Kom University of Suriname. r.tjienfooh@uvs.edu

The dairy industry in Suriname consists of approximately 600 registered farmers who supply milk to the largest of four processing plants, the Melk Centrale Paramaribo. Recent analysis of milk samples have proven that the quality of produced raw milk does not meet the standards. The implementation of good farming practices is important to assure quality and safety of milk. A survey was conducted amongst local dairy farmers to investigate current farming practices and evaluate management on dairy farms. Results proved that in general the management strategies are below standards. It is clear that many farmers lack understanding of effective dairy farming practices. Recommendations were given to dairy farmers on how to improve the quality of milk.

Keywords: standards, raw milk quality, good dairy farming practices

Poster #27

Exploring the Internationalizing of Extension Opportunities:

A Partnership with the Antigua 4-H Youth Program

Norma Samuel¹ and Nicole Walker². University of Florida/Institute of Food and Agricultural Science Marion County Extension Service¹, and University of Florida/Institute of Food and Agricultural Sciences Polk County Extension Service². P.O. Box 9005, Drawer HS03, Bartow, FL 33831-9005; naw@ufl.edu

The Youth Department within the Ministry of Education, Sports and Youth Affairs for the Government of Antigua and Barbuda is charged with reviving an almost dormant 4-H program in Antigua. The need for a structured youth development program is particularly significant in light of recent outbreaks in youth violence. Staff had minimal 4-H knowledge and needed training on use of the Experiential Learning Model (ELM) and understanding the Essential Elements of 4-H.  A needs assessment was conducted to determine how UF/IFAS could assist. Norma Samuel, Marion County and Nicole Walker, Polk County, designed a program to address the needs identified. The objectives were to meet with local and regional officials to develop a 4-H support system; teach the 4-H 101 curriculum to effectively manage 4-H clubs and country-wide programming; design, implement, and evaluate a horticulture judging event; conduct a teen leadership workshop; and gather local information to enhance our own county programs. Each of the objectives was met. A meeting was held with Youth Department staff and various stakeholders to gather information on program history, technical and financial support, and program direction. The major outcome of the 4-H 101 session was an action plan developed by the group outlining the role of the Youth Department staff, partnering organizations in Antigua, and UF/IFAS. The plan is currently being implemented and followed up once per quarter. An annual evaluation of progress is planned starting January 2009. One-hundred percent of the final evaluations for the training session indicated knowledge gained in many areas, including: recognition of competencies critical for healthy youth development; understanding the history and culture of 4-H; targeting specific life skills in 4-H programs; applying the ELM; and starting 4-H clubs. Partnerships between government agricultural agencies and the growing 4-H program may contribute to a renewed emphasis on agriculture among young people.

Keywords: 4-H, experiential learning, youth development

Poster #28

The Impact of ex St. Kitts Sugar Manufacturing Corporation (SSMC) workers on Agriculture in St. Kitts and Nevis - Challenges and Opportunities

Alistair Edwards and Jerome C. Thomas, Department of Agriculture St. Kitts/Nevis. ealistair@hotmail.com

A marked increase in non sugar agriculture has impacted the landscape of the Agriculture in St. Kitts/Nevis. Since the closure of the sugar industry in 2005 the small local market in St. Kitts/Nevis has literally exploded with food crops and other produce creating a problem with distribution. The objectives of this study were to:

1.                   To evaluate the impact that the closure of the sugar industry has had on agricultural development in St. Kitts and Nevis,  and

2.                    To show that agriculture in St. Kitts/Nevis has experienced a shift that can now accommodate exports to nearby islands and an agro processing industry.

We made use of crop forecast primary data, land use data, production data and social assessment of the movement of ex SSMC workers (from sugar to non- sugar) to create a link showing the impact of the closure of the sugar industry.

We developed and analysed quantitative data in the following areas:

1.                    Changes in the acreage of land under non sugar agriculture

2.                    Number of workers moving from sugar to non sugar agriculture

3.                    Comparative production data over a 5-7 year period.

Significance of the findings. Since the closure of the sugar industry, the Government of St. Kitts/Nevis has yet to promulgate a land use policy for the now available sugar cane lands. It is felt that showing the link between the increased number of workers in agriculture and increased production would solidify and present a case for land to be used in agriculture. This is particularly significant especially against a back drop of competing interests for land and a thrust by the country to embark on economic diversification with tourism as the lead industry.

 Keywords: non sugar agriculture, land use policy, tourism

Poster #29

Environmental Damages versus Economic Performance, Sustainability of Guadeloupean Banana Cropping Systems in Question: an Emergetic Approach.

Jean-Marc Blazy, M.Sc¹.; Inacio de Barros, Ph.D¹.; Geraldo S Rodrigues, Ph.D².; Harry Ozier-Lafontaine, Ph.D¹. ¹INRA UR agropédoclimatique, Domaine Duclos, 97170 Petit-Bourg, Guadeloupe (FWI), and ²EMBRAPA Labex Europe. Unité Propre de Recherche Performance des systèmes de culture de plantes pérennes - CIRAD-PerSyst, Avenue Agropolis, 34398 Montpellier, France. jean-marc.blazy@antilles.inra.fr; ozier@antilles.inra.fr

Banana is an important agricultural commodity in Guadeloupe (French West Indies), where banana growers during the last fifteen years have increased their competitiveness in the international market through intensified production with the increased use of man-made technological inputs. Such intensification strategies, that require increased investment, are economically and environmentally risky. In order to assess the environmental performance of banana production in Guadeloupe, emergy synthesis methods were applied to six different types of banana cropping systems previously identified on the island. Additionally, with the aim of improving farmers’ decision-making, environmental performance results and economic analysis for each cropping system were compared. These analyses showed that the greater the environmental benefit of any cropping system, the worse was its economic performance. This main result was corroborated by an increased contrast among cropping systems as related to their dependence on purchased inputs, although all of them are based on the same intensive and arguably wasteful agricultural model. Therefore, the analysis points out that sustainable banana production in Guadeloupe depends on a shift from the high imported fossil (petroleum) based input model to a locally renewable resources intensive one. In this sense, emergy flow analysis shows that innovation towards environmentally sound practices that would enhance nutrient cycling; integrate the control of weeds, pests and diseases; and improve the banana packing process might result in the most positive impacts on overall sustainability. Economic analysis showed that the high labour costs contribute in large measure to the dependence of banana production on public subsidies. Nevertheless, the reorientation of the current European agricultural income policy to an environmentally beneficial performance-based subvention might represent an opportunity to achieve the present social goals while simultaneously advancing the sustainability of banana production.

Keywords: banana; Guadeloupe; cropping systems; environmental impact; agricultural economics

Poster #30

Banana Sector in the French West Indies (FWI) in the 21^st Century: Typology of Farmers’ Room for Manoeuvre in Adapting their Cropping Systems to Crisis.

Jean-Marc Blazy, M.Sc.; Jean-Louis Diman, M.Sc.; François Causeret.; Danny Peregrine, M.Sc. INRA UR agropédoclimatique, Domaine Duclos, 97170 Petit-Bourg, Guadeloupe (FWI). diman@antilles.inra.fr

Production of bananas for export in the French West Indies is passing through a severe economic and environmental crisis. To help farmers in adapting their cropping systems to cope with these new constraints, local agronomic research is focusing on different innovative agro-management techniques. To improve the adoption of innovations, room for manoeuvre of farmers in adapting their cropping system had to be taken into account early in the innovation conception process. The objective of this paper is to present the construction of a farm typology which models the diversity of banana cropping systems management on a regional scale. Indicators were chosen with the help of a conceptual generic model of farmers’ decision making. Data for typology elaboration was collected through interviews with a significant sample of farmers. The typology has been built by combining principal component analysis (PCA) and Agglomerative Hierarchical Clustering (AHC). Correspondence analysis (CA) and analysis of variance analysis (ANOVA) treatments were used to validate the pertinence of the final typology. Six different types of farm were found with a wide range in room for manoeuvre. While some types present high flexibility in terms of work resources reallocation due to the familial and non declared nature of workers, they are highly constrained by low financial margins, cash flow and land availability. The latter could include, for example, a strong limitation for the adoption of improved fallow. On the other hand, some types present high rooms for financial manoeuvre in terms of land use reallocation and financial resources mobilization. However, the latter type has no capacity for managing a temporary decrease in work demand because their manpower is abundant, mainly full-time established and contracted due to the importance of the scope of farm production. Finally, this paper discusses how such kind of study can improve the adoption of innovations through the early integration of farmer’s room for manoeuvre as a framework of constraints into the innovation conception process.

Keywords: banana sector; farmer’s decision; typology; cropping systems; innovation

Poster #31

Village du Millénaire : Expérience d’Haïti

Ronald Bien-aimé. Project Medishare, University of Miami

bronald75@yahoo.es

L'Université de Miami de concert avec l'Université de Floride met en œuvre le premier Village du Millénaire dans le Nouveau Monde.  Ce projet assiste la Section communale de Marmont dans le Plateau Central pour qu'Haïti atteigne sûrement les objectives 2015 des Nations Unies en lui fournissant des services de base (santé, agriculture et développement communautaire).  L'UF a conçu un stimulant programme d'agriculture et d'environnement (janvier 2008), prenant en compte la réalité du pays, pour accroître la production, transformer les surplus, fournir des services de vulgarisation et nourrir 16,000  âmes.  Engager la nouvelle génération a prouvé être une puissante stratégie de communication et est pensé comme étant plus durable dans le moyen et long terme en ce qui concerne la production agro-écologique.

Le Village est aussi un modèle de développement local qui présente les principales caractéristiques suivantes :

a-  L'approche est centrée sur les gens.  Elle les place au cœur du développement, les fait participer de façon active et effective, considérant qu'elle les aide et les accompagne à atteindre leurs propres objectifs de développement.

b- L'approche est holistique.  Elle reconnait l'effet d'influences multiples sur les gens, la présence ou l'apport d'acteurs divers (Gouvernement, ONG, entreprises privées et publiques, organisations de base), l'adoption de stratégies variées par les individus pour s'assurer des moyens d'existence durables.

c- L'approche est dynamique.  Elle met à profit les leçons apprises de manière à renforcer les tendances évolutives positives et à contribuer à réduire les négatives.

d- L'approche renforce les qualités.  Elle priorise les qualités aux besoins.  Elle se propose d'aider les gens à devenir plus résistants, plus forts, mieux préparés et mieux capables d'atteindre leurs propres objectifs.

e- Le modèle prône une approche multidisciplinaire, interinstitutionnelle et intersectorielle.

f- Le développement du modèle s'appuie sur l'utilisation et l'exploitation des ressources humaines et environnementales disponibles localement.  

En somme, le Village du Millénaire repose sur la base stratégique de la réduction de la pauvreté  pour l'amélioration des conditions de vie de la population de Marmont.

Mots clé : développement holistique, Village du Millénaire, Haïti

FORAGE AND LIVESTOCK

Poster #32

Effects of Palm Kernel Cake on Daily Gain and Carcass Yield of Broiler Chicks

Neirin Matos, Rosina Polanco, Carlos M. De Jesús, and Rafael A. Vásquez

Department of Animal Science, Universidad ISA, Avenida Antonio Guzmán Fernández, Km 51/2, La Herradura, Santiago, Dominican Republic. cdejesus@isa.edu.do; car1070@yahoo.com

Corn and soybean meal, used in the diet of broiler chickens are expensive and they are imported commodities in the Dominican Republic. Therefore, alternatives to these feeding ingredients are needed in this country.  Palm kernel cake (PKC) has been shown to improve body weight and feed conversion of chickens, pigs and cattle. However, PKC has not been evaluated under Dominican Republic conditions. The objective of this study was to evaluate the effect of PKC on broiler performance and carcass yield at 43 days of age.  Two separate trials were conducted using a total of 200 chicks per trial, and the results were combined for the statistical analysis. These chicks were randomly distributed into five treatment groups (40 chicks/treatment group/trial). The treatment groups included a normal corn-soybean meal diet, which met or exceeded the nutritional requirements of NRC (1994) or the same diet with 6%, 12%, 24% and 30% of PKC. Chickens were weighed weekly and their feed intake was recorded daily. The feed intake for the whole period of the experiment (43 days) was significantly higher with 6% (3.04 ± 0.18 kg), 12% (3.38 ± 0.18 kg), 24% (3.63 ± 0.18 kg) and 30% PKC (3.60 ± 0.18 kg) than with the PKC control diet (2.42 ± 0.18 kg). The PKC treatments increased the daily weight gain (56.40 ± 1.06 g/d (from day 0 to 43) at 12 % compared to 0% (44.75 ± 1.06 g/d). The feed efficiency was improved with 6% PKC (79.34 ± 1.40) compared with 30% PKC (62.14 ± 1.39). Carcass yield was not affected by the PKC levels. The data of the present study suggest that the addition of PKC to the diet of chicken may substitute for corn without negatively affecting chicken performance. Moreover, PKC may represent a cost-effective alternative for the poultry industry.

Keywords: chicken, palm kernel cake, daily gain

Poster #33

Evaluacion de Nitrogeno Líquido (ULB-35®) para la Produccion de Forraje en Puerto Rico

Alexander Recamán-Serna¹, David Sotomayor Ramírez¹, Yamil Quijano¹ y Gilberto Lozada². ¹ Universidad de Puerto Rico, Colegio de Ciencias Agrícolas, Departamento de Agronomía y Suelos, Mayagüez, Puerto Rico, ³Pan American Fertilizer, Guánica, PR. *  Autor de contacto:  dsotomayor@uprm.edu

La fertilización con nitrógeno (N) representa el costo más alto en la producción de forrajes debido a que se requieren altos niveles de N para lograr altos rendimientos y contenido protéico.  En Puerto Rico, gran parte de la producción de forraje, está destinada para satisfacer la demanda de la industria lechera, por lo que es importante mantener su estabilidad a largo plazo. La utilización de N en forma de urea líquida (ULB-35®) puede mantener los niveles de producción, mejorar la eficiencia de utilización de N, y reducir los costos de producción.  Se realizaron tres experimentos en tres fincas comerciales (Lajas, Sábana Grande y Arecibo) para evaluar la eficacia de ULB-35® sobre la producción y rendimiento del forraje.  En Lajas, se evaluaron tres niveles de ULB-35® (112, 224 y 336 kg N/ha*año) y se compararon con 336 kg N/ha•año de 15-5-10 (N-P₂O₅-K₂O) granulado.  En Sábana Grande, se evaluaron tres fuentes de N: ULB-35®, sulfato de amonio (SA) y mezcla completa de 15-5-10, a una dosis de 336 kg N/ha*año.  En ambos casos, se complementó con fósforo (P) y potasio (K), proporcional a los niveles aplicados con 15-5-10.  En Arecibo, se evaluó la aplicación de ULB-35® en tres concentraciones de N diferentes (1.5% N, 3% N y 7.5% N) y un control con sulfato de amonio.  Los resultados indican que en Lajas, la producción de materia seca de forraje fue mayor para el tratamiento con 15-5-10, seguido de los niveles medio, alto y bajo de ULB-35®.  En Sábana Grande, la producción de materia seca de forraje fue mayor para ULB-35®, seguido por 15-5-10 y SA. En Arecibo, la producción de materia seca fue mayor para SA, seguido por las  concentraciones baja, media y alta de ULB-35®.  Es necesario evaluar formas alternas de aplicación de ULB-35®, para mejorar la eficiencia de utilización en la producción de forraje.

Palabras clave: urea líquida, forraje, fertilización

Poster #34

Tecnicas de Aplicación de Nitrogeno Líquido (ULB-35®) en  la Produccion de Forraje en Puerto Rico

Alexander Recamán-Serna¹, David Sotomayor-Ramírez^1* y Gilberto Lozada²

 ¹ Universidad de Puerto Rico, Colegio de Ciencias Agrícolas, Departamento de Agronomía y Suelos, Mayagüez, Puerto Rico, ²Pan American Fertilizar, Guánica, PR. * Autor de contacto:  dsotomayor@uprm.edu

La fertilización con nitrógeno (N) en la producción de forrajes de corte y pastoreo, se realiza en forma granulada al voleo mediante equipos especiales. Sin embargo, muchas de las vaquerías y fincas productoras de forraje, cuentan con sistemas de riego por aspersión que son utilizados normalmente durante la época seca. La inyección de un fertilizante líquido, al sistema de riego podría mejorar la eficiencia de aplicación y reducir los costos de producción de forraje.   El material ULB-35® es una fuente de urea-N liquido con 15% de N que no contiene metales pesados, patógenos y con bajo biuret disponible en el mercado de Puerto Rico.  El costo del material es 68 y 200% mas barato que la misma cantidad de N en forma de urea y sulfato de amonio, respectivamente.  El uso de ULB-35®, como fuente de N, es una opción que debe ser evaluada y cobra mayor importancia cuando se mezcla con los residuos orgánicos de vaquerías aplicados a pasturas ya que puede mejorar la eficiencia en la utilización del N y aumentar el valor nutritivo del forraje.  Se demostrarán las técnicas de inyección de N líquido a pasturas, en la tubería de succión de la bomba del sistema de aspersión de residuos orgánicos, en el sistema de riego aéreo por cañones, sistema de riego con pivote central y por aspersor móvil.

Palabras clave: sistema de riego, urea liquida,  forraje, fertilización.

Poster #35

Plant Density and Dry Matter Yield of ‘Ubon Stylo’ (Stylosanthes guianensis) in an Oxisol

Jorge Luis Olivares¹, Elide Valencia¹ and Abner Rodríguez-Carías ².  ¹Agronomy and Soils Department and ²Department of Animal Industry, Univ. of Puerto Rico, Mayagüez. jolivares67@hotmail.com

The focus of this research was to evaluate the persistence, yields of dry matter and chemical composition of ‘Ubon Stylo’ (Stylosanthes guianensis) (95% germination) at three seeding rates (5, 10, 15, and 20 kg/ha).  ‘Ubon Stylo’ was planted in August 2007 at the Isabela Substation of the Agricultural Experimental Station, University of Puerto Rico. The aftermath was at 100 days post-planting and regrowth harvest occurred ninety days thereafter. The experimental design was a complete randomized block with four replicates for the seeding rates.  The variables evaluated were: biomass fresh yield (YB) and dry matter yield (DMY). The results show significant differences (P<0.05) between the amounts of biomass at different seeding rates. Thus at a seeding rate of 5 kg/ha, the mean yield of 11,450 kg/ha was statistically different from the mean yield of 20,000 kg/ha obtained at the seeding rate of 10 kg/ha. Mean yields from these low seeding rates differed statistically from the mean yields obtained with seeding rates of 15 kg/ha and 20kg/ha, which were 26,025 and 29,800 kg/ha respectively. The latter two mean yields did not differ statistically. The mean dry matter yield at 5 kg/ha was 1637.6 kg/ha, which differed significantly from the dry matter yields obtained at the 3 higher seeding rates, which were 4260, 3906,  and 4485 kg/ha, respectively.

Keywords: seeding rates, yield, dry matter

Poster #36

Effects of planting density and cut frequency on dry matter yield of Mulberry (Morus Alba) and Guacima (Guázuma ulmifolia).

Ramón A. Marte Estévez¹, Carlos M. de J. Arias²*, Rafael A. Vásquez Martínez³. ¹Veterinary Medicine and Animal Science Department, ²Animal Science Department. ³Facultad de Ciencias Agroalimentarias y del Ambiente, Universidad ISA, La Herradura, Santiago, Republica Dominicana. ramonmarte@yahoo.com;  rmarte@isa.edu.do;  cdejesus@isa.edu.do; car1070@yahoo.com

 

A study was conducted to evaluate the dry matter (DM) yield and nutritional composition of mulberry and guacima under 3 planting densities and 3 cutting frequencies. Each treatment combination of 2 x 3 x 3=18 was replicated four times in a randomized complete block design. Four plants per plot were randomly selected to determine their DM and crude protein contents. An increased mulberry dry weight yield (P<0.05) was obtained with 25,000 plants/ha and a cutting frequency of 60 d, whereas and even high dry matter yield was obtained with 25,000 plant/ha and a cutting frequency of 75 d. The average plant height of mulberry was 280.3±43.4 cm and the average plant height of guacima was 260.9±43.4 cm. The leaf crude protein content was 28% in guácima with a planting density of 25,000 plants/ha and a cutting frequency of 75 d. However, the leaf crude protein content of mulberry was 21.9% with 25,000 plants/ha and a cutting frequency of 45 d. We conclude that the best planting density is 25,000 plants/ha for both species, and the best cutting frequency is 60 d for mulberry and 75 d for guacima.

Keywords: guacima, mulberry, density plantation, cut frequency

Poster #37

The Mineral Status of Sheep and Goats with Reference to Swayback in Central Trinidad

Aphzal Mohammed¹ and Fayez G. Youssef ².  ¹The University of Trinidad and Tobago, lot 74-98 O’Meara Industrial Park, Arima Trinidad; ²Department of Food Production, The University of the West Indies, St. Augustine, Trinidad, West Indies. aphzal.mohammed@utt.edu.tt

There have been many occurrences in Trinidad of lambs and kids that have died within 6 months of birth of Cu deficiency resulting in swayback. Animals displayed an inability to stand at birth or hind limb ataxia progressing to paralysis in the delayed forms. The condition continues to be of economic importance because there is a poor growth rate and an high mortality among affected lambs and kids. The study deals with the mineral status of (i) swayback (n = 50) and apparently normal lambs (n = 39) and adult sheep (n = 42) and (ii) swayback (n = 24) and apparently normal kids (n = 21) and adult goats (n = 41) of Central Trinidad.

Calcium, Mg, Na, K, Cu and Zn concentrations were evaluated by atomic absorption spectroscopy and colorimetrically for P, on blood serum of swayback and apparently normal animals. The identical minerals including Fe and Mn were evaluated on grasses (n = 45) of swayback affected farms or locations. Significantly lower (p < 0.001) serum Ca, Cu, and Zn levels were found in swayback than in apparently normal lambs and adult sheep. Serum Cu was also lower (p < 0.001) in swayback than in apparently normal kids and adult goats. Several swayback lambs had low concentrations of Ca (< 2.0 mmol/L), P (< 1.3 mmol/) and Zn (< 9.2 mmol/L), while most swayback lambs and kids had critically low Cu (< 7.9 mmol/L). Several adult sheep and goats were also deficient in Cu and P, while about half of the grasses analysed had low Cu (< 5 ppm). Critically low serum Cu in swayback lambs and kids was probably caused by the low Cu concentrations found in the grasses. Twenty four, 47 and 16% of grasses also had levels of Ca, Mg, and P below minimum requirements (< 0.20% DM).The study provides a basis for the inclusion of Cu and P supplementation to enhance productivity of sheep and goats of Central Trinidad.

Keywords: apparently normal, swayback, copper

Poster #38

Lambs’ Voluntary Intake and Digestibility of Forage Soybean ‘Henson Long Juvenile’ (Glycine max) and Lablab ‘Rongai’ [Lablab purpureus (L.) Sweet]

F. Rivera-Melendez ¹ A. Rodríguez-Carías ¹ and E. Valencia². ¹Department of Animal Industry and ²Agronomy and Soils Department, Univ. of Puerto Rico, Mayagüez. elideval@uprm.edu; franprm@gmail.com

In Puerto Rico, tropical grasses do not meet the nutritional requirements of dairy cows.  For this reason, alfalfa hay and costly concentrate based diets are used in the dairy industry.  It has been widely documented that legumes are higher in nutritive value than tropical grasses, but information on forage intake and nutritive value of the annual legumes forage soybean ‘Henson Long Juvenile’ (‘HLJ’) (Glycine max) and lablab ‘Rongai’ [Lablab purpureus (L.) Sweet] is limited.  The research objective was to compare daily intake, dry matter digestibility, crude protein (CP), and neutral detergent fiber (NDF) digestibility of ‘HLJ’ and ‘Rongai’ hay when fed to mature lambs.  The experiment was conducted at the University of Puerto Rico, Finca Alzamora using rams (28.4±4 kg BW) in a completely randomized design with three replicates. Rams were housed in individual cages and fed treatment diets for a 7d adaptation period and 5d data collection.  Higher voluntary feed intake (P<0.05) by rams fed ‘HLJ’ than ‘Rongai’ (943 vs. 852 g/d) was observed.  However, CP and NDF digestibility of ‘HLJ’ and ‘Rongai’ did not differ (P>0.05).  Crude protein and NDF were 15.7 and 15.5% and 42.8, and 41.7% for ‘HLJ’ and ‘Rongai’, respectively.  Digestibility (56.2 vs. 49.6%) was higher (P<0.05) in ‘HLJ’ than ‘Rongai’.  Both ‘HLJ’ and ‘Rongai’ exhibit potential for use in hay conservation systems to improve the feeding value of grass hay and minimize concentrate use in dairy cows. 

Keywords: voluntary intake, forage soybean, lablab

Poster #39

Composición Química de Stylosanthes guianensis Fresco o Fermentado en Pacas Cilíndricas durante dos Periodos de Fermentación

Vázquez, M.S. ¹, A.A. Rodríguez ¹, E. Valencia ² y P. Randel ¹. ¹Departamento de Industria Pecuaria y ² Departamento de Agronomía y Suelos, Universidad de Puerto Rico, Recinto Universitario de Mayagüez. marie_socky@hotmail.com

Las leguminosas tropicales ofrecidas como forraje fresco o heno son una alternativa para utilizarlas en dietas para rumiantes, sin embargo, su uso potencial como henilaje fermentado en pacas cilíndricas todavía no está bien documentado. El objetivo de este estudio fue comparar la composición química de heno de gramíneas tropicales (HGT) y Stylosanthes guianensis fresco (SGF) o henilado en pacas cilíndricas durante 30 (SGF1) o 72 días (SGF2). Muestras de HGT y de SGF se analizaron para determinar su contenido de MS, PB, FDA, FDN, hemicelulosa (FDN-FDA), carbohidratos no fibrosos (CNF) y NDT. Además, tres pacas de stylosanthes a cada largo de fermentación (SGF1 y SGF2) se analizaron para las mismas variables de composición química y para la relación N-NH₃/N-total. La data se analizó mediante un diseño completamente aleatorizado utilizando el paquete estadístico de SAS.  La separación de medias se realizó mediante la prueba de Tukey.  La composición química del SGF fue de 14.1% PB, 59.80% FDN, 47.00% FDA, 20.50% CNF, 57.00% NDT y 12.80% hemicelulosa, mientras que la de HGT fue de 7.01% PB, 70.70% FDN, 41.8% FDA, 15.90% CNF, 54.00% NDT y 28.90% hemicelulosa. Henilar SG en pacas cilíndricas durante 30 o 72 días disminuyó el contenido de CNF 7.7% y 2.77% respectivamente, pero aumentó el contenido de FDN 9.60% después de 30 d de fermentación y 3.60% después 72 d. La relación N-NH₃/N- total fue mayor en SGF2 (7.38%) que en SGF1 (4.16%).  En resumen, SGF contiene un mejor perfil de nutrientes que HGT. Henilar SG en pacas cilíndricas degrada proteínas a N-NH₃, disminuye el contenido de CNF y aumenta el % de FDN, sin embargo estos cambios son menos apreciables en henilaje fermentado durante períodos de fermentación más cortos (30 vs 72d).

Palabras Claves: Stylosanthes, Henilaje, pacas cilíndricas

Poster #40

Liquid Urea Rate Effects on Nutritive Value of 8-Week Regrowth of Guineagrass (Panicum maximum Jacq.) Hay  

Luis Almodovar¹, Elide Valencia¹ and Abner Rodríguez-Carías.  ¹Agronomy and Soils Department, and ²Department of Animal Industry, Univ. of Puerto Rico, Mayagüez. luis_almodovar@eea.uprm.edu

Guineagrass (Panicum maximum Jacq.) is a valuable grass in grazing systems in Puerto Rico, but when conserved as hay, its low protein (<6.0%) concentration limits both meat and milk production.   This study assessed the effect of applying liquid urea (LU) on hay harvested at 8-weeks regrowth of guineagrass cvs. ‘Mombasa’ and ‘Tanzania’ hay.  Liquid urea were applied in a fine mist at baling at low (L; 0 lt/ha), medium (M; 204 lt/ha) and high rate (H; 807 lt/ha).  Hays were stored for 8 week and core samples (250 g) were taken for determination of chemical composition of crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF) using a completely randomized design.  There were cultivar effects and LU rate effects (P<0.05) for CP, but there was no interaction. Crude protein averaged 13 and 17.7% for cv. Mombasa and Tanzania, respectively.  There was a linear increase (P<0.05) in CP with an increasing rate of LU.  Mean CP was 12, 15 and 20% for the L, M, and H rate, respectively.  Additive LU did not affect (P<0.05) either NDF or ADF concentration in Mombasa and Tanzania.   This study shows that adding LU at baling increases CP, but has no effect on NDF or ADF.   Liquid urea at either concentration can be used to increase the nutritive value of low quality hay in Puerto Rico.  Forage intake and digestibility and nitrogen balance studies, however, are needed to determine potential losses of N.     

Keywords:   grazing systems, crude protein, NDF, ADF

Poster #41

Fermentation Characteristics and Consumption of Forage Sorghum and Sudax Ensiled in Round Bales

W. Rodríguez¹, A.A. Rodríguez¹ and E. Valencia ². ¹Departament of Animal Industry¹ and ²Department of Agronomy and Soils, University of Puerto Rico, Mayagüez Campus. Wandaliz_rodriguez@yahoo.com; abner@uprm.edu

Forage sorghum ([Sorghum bicolor (L.) Moench.] is an important forage crop in the tropics because of its high productivity and ability to utilize water efficiently. However, information about it potential use in ruminant diets as haylage fermented in round bales (RB) is limited. The objective of this experiment was to compare the fermentation characteristics forage sorghum and sorghum x Sudangrass hybrid (Sudax) and to determine daily intake by sheep. Forage sorghum (FS; DM 34%) and Sudax (DM 35%) were harvested at 90 days of growth and preserved as haylage in round bales (RB; 400 kg).  Eight RB per variety were prepared and two were opened and sampled after 3,7,14 and 30 d of fermentation and pH and fermentation products determined. Data was analyzed as a completely randomized design with a 2 (sorghum varieties) by 5 (days of fermentation) factorial arrangement of treatments. To assess forage intake, 8 lambs were assigned to either forage (N=4) in individual pens. Forages were offered and orts were collected during 12 d with a 7 d adaptation and 5 d data collection period.  Daily forage on offer was 3% of lamb BW on dry matter basis. Final pH was lower (P<.05) in FS (6.10) than in Sudax (6.14), however, sorghum variety did no affect final lactic acid, acetic acid and butyric acid content. There were no differences in forage intake between varieties by lambs (624 and 676 g/d for FS and Sudax, respectively). In summary, fermentation characteristics of SF were greater than Sudax as evidenced by lower pH, however, sorghum variety did not affect lamb haylage intake.

Keywords: Sorghum, haylage, round bales, lambs intake

Poster #42

Composición Química y Consumo Voluntario de Calliandra calothyrsus Deshidratada o Fresca por Ovinos y Caprinos

Lisa Dillon¹, Melanie Román Zayas¹,  Abner A. Rodríguez Carías¹ y Elide Valencia². ¹ Departamento de Industria Pecuaria ² Departamento de Agronomía y Suelos, Universidad de Puerto Rico, Recinto de Mayagüez. abner@uprm.edu, ldf23932@uprm.edu

Se realizaron dos experimentos con el objetivo de evaluar la composición química y la inclusión de hojas de Calliandra calothyrsus deshidratada (CCD) o ramas frescas de la misma leguminosa (CCF) a razón de 25% de la materia seca (MS) dietética sobre el consumo voluntario (CV) de heno de gramíneas tropicales (HGT) utilizando ovinos y caprinos. Se utilizaron cuatro caprinos en el experimento uno con CCD y cuatro ovinos con CCF en el experimento dos. En cada estudio los animales fueron confinados en jaulas individuales y alimentados con 100% HGT ó 75% HGT y 25% CCD o CCF. El ofrecimiento del forraje fue basado en un CV de MS total estimado en 4% PV/d.  Los forrajes se analizaron para determinar su contenido de PB, FND y FAD. Ambos experimentos se llevaron a cabo durante dos periodos de diez días con cinco días de adaptación a la dieta y cinco días de recolección de data. En cada estudio, se registró la cantidad de forraje ofrecido y rechazado para calcular el CV. La data de ambos experimentos se analizó según un diseño cuadrado latino 2 * 2.  Los valores de PB, FND y FAD de CCD fueron de 14.2, 40.9 y 33.9 %, respectivamente. Las ramas frescas de la leguminosa presentaron contenidos de PB, FDN y FDA de 10.6, 58.6 y 55.3%, respectivamente. En Ambos experimentos el consumo total de forraje fue mayor en cabros y ovinos alimentados con 75% HGT y 25% CCD o CCF que los alimentados con 100% HGT. En resumen, la composición bromatológica y la forma física (hojas vs. ramas y deshidratada o fresca) afecta la composición química de Calliandra calothyrus. Sin embargo, en ambos experimentos los animales demostraron un mayor CV cuando se les ofreció 25% CCD o CCF en la dieta. La CC henificada o fresca representa una excelente fuente de nutrientes para pequeños rumiantes. Estudios futuros deben realizarse incluyendo CCD o CCF en la dieta en porcientos mayores de 25.

Palabras Claves:

Poster #43

The Evaluation of Three Feeding Regimens and Three Anthelmintics in a Meat Goat Production System: a Florida A&M University Research/ Extension Project

*Thomas Peterson, *R. Mobley, *G. Nurse, *F. Okpebholo, *C. Lyttle-N’guessan, *G. Queeley, *T. Kahan; *Cooperative Extension Program, College of Engineering Sciences, Technology and Agriculture, Florida A&M University, Tallahassee, Florida.  Thomas.peterson@famu.edu

Food safety starts at the farm gate. Proper management and feeding are important to the productivity and survivability of the farm as well as to the health and safety of the food supply. Nutrition and internal parasites are two factors that affect the growth of the meat goat industry in Florida. The project evaluated three common feeding strategies [(i) a cracked corn feed, (ii) a 12% crude protein commercial feed, and (iii) a 16% crude protein commercial feed)] and three anthelmintics for their effects on weight gain and economic efficiency, and any resistance among the herd, respectively. The results indicated that the 12% crude protein commercial feed-feeding regimen was the most economical / sustainable, and had the lowest weight gain. In addition, the results indicated that Florida A&M University, Research Extension Center herd might be resistant to the Levamisole type anthelmintic. One of the objectives, also, was to apply the most efficient resources to maintain food safety. The aim is to attain healthier animals through proper nutrition, weight gain and carcass quality, thereby maximizing safe food supply.

Keywords: food safety, anthelmintic resistance

Poster #44

Stocking Rate Trial with Boer X Spanish Goats under Thinned Loblolly Pines

Nadine Gordon-Bradley, and O. U. Onokpise, Agronomy, Forestry and Natural Resources Conservation Program, College of Engineering Sciences, Technology and Agriculture, Florida A&M University, Tallahassee, Florida 32307. gordonnadine@hotmail.com

Goat meat is said to be one of the most highly consumed meat in the world (Engle et al., 2000). The perception of using goats for vegetation management other than as a grazing livestock remains very high. As the demand for goats increases due to healthy diet needs and ethnic population presence, the need to increase production using various grazing practices for small ruminants has begun to receive attention. The study was conducted to determine stocking rates of Boer x Spanish goat crossbreeds in a silvopastoral system of loblolly pines and Tifton9 bahiagrass. The experimental area consisted of loblolly pine plantation that was planted in 1979 and thinned in November 2001 to 1.2 x 12m spacing. Tifton-9 bahiagrass was planted between widely spaced loblolly pine trees.  Treatments consisted of (1) shaded pastures and open pastures of Tifton-9 bahiagrass as the main plots, and (2) two stocking rates (10 and 17 goats per ha) crossbred goats as the subplots using a split-plot design. Goats grazed paddocks using a rotational stocking method. Live weight data was used to calculate the average daily gain (ADG) and weight gain or loss of animals over the grazing period to determine recommended stocking. For Year 1, there was no significant difference in ADG of the animals for the shade treatment (P = 0.124) or stocking rate treatment (P = 0.673). For Year 2, the results showed a significant effect of stocking rate (P = 0.003) on ADG. The result from this study indicated that the low stocking rate was best for the goats evaluated. High stocking rates for both years caused lost weight and thus indicating that the stocking was too high for the paddock sizes used for the study. A silvopastoral system with goats at a stocking rate of 10 goats ha^-1 averaging 34 -45 kg body weight on bahiagrass grown under trees can provide adequate forage. 

Keywords: silvopastoral system, Tifton-9 bahiagrass

Poster #45

Effects of Palm Kernel Cake in the Diet of Dairy Goats on Milk Production, Composition and Kid Daily Gain

Juan C. Ureña, Marco E. Fernández, Carlos M. De Jesús, and Rafael A. Vásquez. Department of Animal Science, Universidad ISA, Avenida Antonio Guzmán Fernández, Km 51/2, La Herradura, Santiago, Dominican Republic. cdejesus@isa.edu.do; car1070@yahoo.com

A field trial was carried out to evaluate the effects of the inclusion of palm kernel cake (PKC) in diets of dairy goats on goat performance, milk yield, kid daily gains and, milk composition.  Forty-eight (48) last quarter gestating crossbreed dairy goats in the last quarter of gestation with 54 kg of BW were randomly distributed in eight PKC treatments arranged in 3 blocks in a randomized block design. The treatments were 0, 15, 30, 45% of PKC and two milking frequency (one and twice at day).  The dairy ration was formulated (NRC, 1981) to contain 62.93 g of DP and 2.4 Mcal/kg NEL per dairy goat weighing 54 kg and producing milk containing 4.0 % milk fat. The ration consisted in hay grass (Transvala) and grains supplement. Body condition, feed intake, profit, milk production and composition, were measured with respect to the dairy goats and daily gain was registered with respect to the kids. The body condition was not affected by the PKC levels. The PKC treatments did not affect goat feed intake, which was 2.81kg /animal/d and 1.92 kg/animal/d when goats were milked once or twice per day, respectively. The average kid daily gain was 72.57 g/d in those fed by goats that were milked once per day. Milk production was 18.62 kg per animal and 12.95 kg per animal in goats milked once and twice per day, respectively. The milk of dairy goats milked twice per day had higher milk fat content (4.45 %) than of those milked once per day (3.45 %).  With goats milked once per day the highest profit was obtained with 15 % of PKC in the ration, and with goats milked twice per day the highest profit was obtained with 30 % of PKC in the ration.

Keywords: dairy, goat, feed intake, milk, yield, ration

Poster #46

Development of Small Scale Aquaculture Farms in North Florida

Uford A. Madden¹, G. Nurse¹, J. Beaudouin¹, A. Bolques¹, S. Harris-Thompson¹ A. Wallamsley², M. May³, and F. Chapman⁴, ¹Extension and Outreach Program, College of Engineering Sciences, Florida A & M University, Tallahassee, Florida ²Florida Farm Bureau Federation, Gainesville, Florida, ³Florida Department of Agriculture and Consumer Services, Tallahassee, Florida, and ⁴University of Florida, Gainesville, Florida. uford.madden@famu.edu

This program provides teaching, research and extension assistance to small farmers operating small-scale aquaculture farms, which utilize natural water bodies to contribute to food production. Thus the program supports the development of the aquaculture industry and the economy of Florida. A specific objective was to bring together production, economic and marketing specialists in integrated demonstration of projects to optimize production systems (ponds, tanks, raceways cages and hybrid systems), spawning and hatchery techniques, microencapsulated feeds, batch plankton culture procedures, preventive aquatic animal health practices and product value.  The program addresses problems/needs of small, limited resource and economically disadvantaged farmers and facilitates cooperation of specialists and county agents in finding solutions to various challenges encountered in the industry. Initially the project involved ten (10) existing and new farmers in counties within a one hundred (100) mile radius.  Farmers currently growing fish and those interested in growing fish, with or without ownership of existing water bodies, were identified. The project began in July 2006 at FAMU Research and Extension Center, Quincy, Florida, where there are ponds; and it provided classroom and hands-on training and a farm visit was made with each farmer. A training curriculum was developed with modules and information used for the instruction. Fourteen farmers were trained on the best management practices and alternative methods for improvement of production systems for fish (e.g. Bait fish and Sturgeon). Marketing strategies were addressed to sustain the increased production of fish and profitability. Four ponds were revitalized and once per week pH, temperature, depth and dissolved oxygen data were collected as the ponds stabilized. Brochures were developed to support development of small scale enterprises, production of fingerlings and utilization of existing natural resources and reduction of specialized inputs.

Keywords: Aquaculture, small scale farms, fish production

Poster #47

Comparison of Oral Administration of Various Doses of Moxidectin and Ivermectin Pour-On Formulations against Intestinal Parasites in Meat Goats

Uford A. Madden¹, N. Wilson ², G. Nurse¹ and J. Beaudouin¹, ¹Extension and Outreach Program, College of Engineering Sciences, Technology and Agriculture, Florida A& M University, Tallahassee, Florida, and ²Marion County Extension, University of Florida, Gainesville, Florida.  uford.madden@famu.edu

A total of 64 meat goats (6 months old) were used to investigate the effects of various doses of two anthelmintics on naturally occurring intestinal parasites in two feeding systems (32 animals each). Animals in the extensive system received grazing only and those in the semi-intensive system received grazing plus 1.1 kg of a 12% protein pellet per head per day. Animals in both systems received treatments of Moxidectin (MOX) and Ivermectin (IVM) at 0.275 mg/kg; 0.550 mg/kg and 0.825 mg/kg bodyweight and 0 mg/kg (CONT). Two males and 2 females were randomly assigned to each treatment. A single dose of MOX or IVM was administered orally to each treated animal at Day 0. A fecal sample was taken from each animal on Days 0, 7, 28, 56, and 84 for evaluation of parasite eggs. Body weights were taken on Days 0, 28, 56, and 84. Sampling began on March 8, 2005 and ended on June 15, 2005. In the extensive system, IVM-treated animals (19.95 kg) had a higher average bodyweight gain than those treated with MOX (17.14 kg). MOX-treated animals, 0.550 mg/kg had slightly higher bodyweight gain (5.77 kg) than CONT animals (5.14 kg). In IVM-treated animals, 0.825 mg/kg had the highest bodyweight gain (6 kg). In the semi-intensive system, MOX-treated animals (25.23 kg) had slightly higher average bodyweight gain than IVM-treated (24.64 kg). MOX-treated, 0.825 mg/kg and CONT animals had similar bodyweight gain (6.59 and 6.54 kg). IVM-treated animals, 0.825 mg/kg had the highest bodyweight gain (7.59 kg). Fecal samples showed marked reductions in parasite egg counts in MOX-, IVM-treated and CONT animals for both systems. In the extensive system, MOX-treated animals, had parasite eggs only in animals treated with 0.550 mg/kg whereas IVM-treated animals had no eggs in animals treated with 0.825 mg/kg, and CONT animals at the end of the study. In the semi-intensive system, no parasite eggs were detected in any sample in MOX- treated but were in CONT animals at the end of the study. In IVM-treated animals, 0.550 mg/kg, and CONT animals, no parasite eggs were detected at the end of the study.

Keywords:  Moxidectin, ivermectin, meat goats

Poster #79

A Comparison of Grass vs. Legume Free Range Small Ruminant Finishing Systems for the Tropics. 

S.A. Weiss, R. Ben-Avraham, R.C. Ketring, and R.W. Godfrey, Agricultural Experiment Station, Agronomy Program, University of the Virgin Islands, St. Croix. stuweiss@yahoo.com

Small Ruminant Special Session during evening Poster Session

Tuesday July 15, 2008, Mediterranean West and Center

The objective of the present study was to evaluate live animal performance and carcass characteristics of Dorper X St. Croix White lambs managed in two types of post-weaning alternative pasture finishing systems in the tropics.  After weaning and background grazing on native pasture for eight months, lambs (n = 37) were stratified by weight and sex into two treatments consisting of native pasture (NP) and improved pasture (IP), with energy supplement. Native pasture consisted of a mix of guinea grass (Panicum maximum) and hurricane grass (Boithrocloa pertusa), while IP consisted of a mix of seeded tropical legumes (Vigna unguculata, Clitoria ternetea, and Lablab purpureus) and volunteer guinea grass in 0.45 ha paddocks where forage availability was not a limiting factor.  All lambs were supplemented with crushed corn daily at a rate of 1 % of their body weight for 100 days and slaughtered at approximately 365d of age.  During the finishing trial IP lambs had greater total weight gain (P < 0.0001) than NP lambs (10.7 ± 0.4 vs. 7.5 ± 0.4 kg, respectively). In addition, IP lambs had higher ADG (P < 0.0002) than NP lambs (104.3 ± 4.5 vs. 77.9 ± 4.5 g/d, respectively).  Compared to NP lambs, IP lambs were heavier at slaughter (P < 0.05; 40.6 ± 1.1 vs. 36.9 ± 1.1 kg, respectively) had heavier carcasses (P<0.05; 20.5 ± 0.6 vs. 18.1 ± 0.6 kg, respectively) and greater dressing percent (P < 0.05; 50.4 ± 0.4 vs. 48.9 ± 0.4 %, respectively).  Further, IP lambs had greater body wall thickness (P < 0.05; 14.1 ± 0.6 vs. 11.9 ± 0.6, mm, respectively) and rib eye area (P=0.08; 10.1 ± 0.3 vs. 9.2 ± 0.3 cm², respectively) than NP lambs.  Back fat thickness, KPH fat, and leg circumference for IP and NP lambs was not significantly different.  Results of this study indicate that the adoption of alternative pasture finishing practices utilizing mixed legume improved pasture with corn supplementation can lead to improvements in animal performance and carcass muscularity of crossbred hair sheep lambs under tropical conditions.

Keywords:  sheep, legumes, pasture finishing, carcass characteristics

CROP PROTECTION AND PEST MANAGEMENT

Poster #48

First Report of Cladosporium tenuissimum Cooke on Taro in Puerto Rico

Evelyn Rosa-Márquez¹ and Carlos E. Ortíz ²

Crop Protection Department, Agricultural Experiment Station, Agronomy and Soils Department, University of Puerto Rico, Mayagüez. eve_rosa@hotmail.com

Cladosporium tenuissimum Cooke has been identified in Puerto Rico on taro [Colocasia esculenta (L.)] Schott.  At the onset of the symptoms, the fungus causes reddish-brown leaf spots that become tan to brown with age. Spots are circular or irregular. In the upper leaf surface pale greenish- yellow spots were observed that belongs to the corresponded spot at the lower. Spots often coalesce to form large necrotic areas.  Pathogen city test were performed with pure culture of the fungus, isolated in potato-dextrose agar by misting conidial suspensions in sterile distilled water on healthy plants in pods.  Typical lesions developed six days after inoculation.  The causal agent was reisolated.  This fungus was having been previously reported in both Cuba and Puerto Rico.  It is reported here for the first time in Puerto Rico affecting both cultivated and non-cultivated taro.

Keywords: disease symptoms, Koch’s postulates

Poster #49

Relación entre las Propiedades Físicas de un Oxisol y Coberturas Vegetales en la Incidencia de Phytophthora cinnamomi en Aguacate Persea americana Mill.

Torres Ordóñez B.¹, C. Estévez de Jensen², V. Snyder¹ y M. Vazquez¹.

(1) Departamento de Agronomía y Suelos, UPR, Mayagüez, Colegio de Ciencias Agrícolas Mayagüez Campus P.O. Box 9032 Mayagüez, Puerto Rico 00680. E-mail: bettorres25@yahoo.com (2) Departamento de Protección de Cultivos, UPR, Mayagüez

En Puerto Rico se importa el 80 por ciento del aguacate que se consume, lo cual indica el potencial económico de aumentar la producción local del cultivo.  Sin embargo, las áreas de producción se han visto afectadas con la alta incidencia y severidad de pudrición de la raíz asociada a Phytophthora cinnamomi.  Dicha condición se ve acentuada por condiciones de saturación del suelo durante la época lluviosa (julio – diciembre), altas temperaturas,  y agrietamiento del suelo en épocas de sequía que causan daño mecánico al sistema radicular.  En mayo de 2006 se estableció un huerto con la variedad Semil 34/Semil 34 (patrón/injerto) para evaluar la influencia de Arachis pintoi y Arachis glabrata en un Cumulic Haplustoll, serie San Antón, franco arcilloso. Las coberturas fueron establecidas alrededor de los árboles en junio de 2006, las cuales se comparan con un control (no cobertura leguminosa) en un diseño completamente aleatorizado con 4 repeticiones por tratamiento.  Las propiedades físicas del suelo consideradas en este estudio son: estabilidad de agregados donde después de 20 meses de establecidas las coberturas se encontró diferencias significativas (p<0.05) entre el tratamiento con Arachis glabrata, 46.24%, versus el control, 22.36% de estabilidad, también se encontraron diferencias significativas en infiltración en campo, potencial mátrico inicial.  Hasta el momento no se han encontrado diferencias significativas para Densidad aparente, permeabilidad en laboratorio, y curvas de retención de humedad, pero cabe destacar un mejor comportamiento de estas propiedades con las coberturas versus el control. Algunas propiedades químicas evaluadas fueron Nitrógeno total y Fósforo, en donde se encontraron diferencias significativas; no se han encontrado diferencias en materia orgánica, ni en pH. Se continuará evaluando las propiedades del suelo hasta completar un período de dos años.

Palabras Clave: Arachis pintoi, Arachis glabrata, aguacate, propiedades físicas de suelos.

Poster #50

Weed Management during Rhizoma Perennial Peanut Establishment

María de Lugo-Torres¹ and Teodoro M. Ruiz², ¹ Crop Protection Department and Animal Science Department, University of Puerto Rico; ² Gurabo Agricultural Experiment Station, Gurabo, P.R. mlugo@uprm.edu

Dairy and beef production are among the most economically important agricultural activities throughout the United States islands in the Caribbean. Therefore, there is considerable interest in improving both production and quality of forages. Currently, rhizoma perennial peanut is considered an alternative forage in the Caribbean because of its low requirements for nitrogen fertilization, relatively high protein content, and adaptability to contrasting ecological zones. Studies and field observations have shown that during establishment rhizoma perennial peanut is a poor competitor against weeds. Management strategies, such as chemical weed control, must be used to offset the slow establishment rate. A study was conducted to evaluate rates and dates of application of the herbicides dimethenamid and imazethapyr followed by clethodim and bromoxynil for weed control in rhizoma perennial peanut during establishment.  Excellent grass control was obtained when dimethenamid was applied during the first month. At six months after application, excellent grass control was obtained with all herbicide combinations. Across rates and dates of herbicide applications, the best weed control was obtained when treatments were applied soon after planting.

Keywords: rhizoma perennial peanut, weed management

Poster #51

Black Sigatoka IPM in Puerto Rico

W. Almodóvar¹ and M. Díaz², ¹ Crop Protection Department, and ² Horticulture Department, University of Puerto Rico, Mayagüez Campus. walmodovar@uprm.edu

The Black Sigatoka Management (BSM) Program of the University of Puerto Rico Extension was funded in part by the Southern Region IPM Center and the USDA/ES/IPM program. There were two field day workshops for Extension Agents held at the Gurabo Research Station. Each workshop introduced the concepts and practice of BSM. Seventy-five Extension Agents were trained to identify the stages of Black Sigatoka, determine the incidence of this disease using the Stover scale, and calculate the percentage infection. An experimental plot of plantain infected with the disease was used for this purpose. A field guide with an electronic presentation in Spanish about BSM was created. Each attendee received a copy of these educational materials, and agreed to conduct field day and training meetings for growers on the topics discussed in the BSM program. All attendees increased their knowledge and attitudes toward non-chemical management of Black Sigatoka, and pesticide safety. They considered the field guide and the set of electronic presentations appropriate to train growers to implement effective and environmentally responsible management strategies for the protection of plantain and banana from Black Sigatoka. The outcomes of this project will lead to reduce the potential for Black Sigatoka problems on plantain and banana and to decrease pesticide use in the environment. This project expands the existing pesticide safety, and IPM programs in Puerto Rico. The field guide and electronic presentations about the BSM can be reached at http://academic.uprm.edu/walmodovar .

Keywords: Stover scale, plantain, banana, strategies

Poster #52

Crianza Masiva de Mirax insularis Muesebeck,  el Parasitoide Exótico del Minador del Café, Leucoptera coffeella Guérin-Ménéville, en Puerto Rico.
Fernando Gallardo, Evelio Hernández  Marcela Daza y Jennifer Pagán
Universidad de  Puerto Rico,  Recinto Universitario de Mayagüez, Colegio de Ciencias Agrícolas, Estación Experimental Agrícola, Departamento de Protección de Cultivos, Aptado 9000 Mayagüez, PR 00920. fgallardo@uprm.edu

El minador del café es una de las plagas principales del cultivo del café mundialmente.  Cuando las prácticas de control no son apropiadas ocasionan defoliación a los arboles de café afectando su producción. Desde hace algunos años se han estado buscando alternativas de control que sean viables tanto económicamente como ambientalmente. Una de las técnicas sugeridas es la incrementación de uno de sus más abundantes parasitoides, el bracónido,  Mirax insularis Muesebeck, mediante crianza y liberaciones masivas en el campo.  Para la crianza masiva del huésped del bracónido utilizamos plántulas de café (Coffea arabica L. cultivar Catuaí)  de tres meses.  Expusimos sesenta y cinco plántulas de café, cultivadas libres de insectos, a 60-80 adultos del minador del café dentro de una cajuela de infestación durante tres días.  Removimos las  plántulas al cuarto día después de la infestación y a los tres días siguientes introducimos los adultos del parasitoide para que parasitaran las minas presentes en las hojas por espacio de 48 horas.  Al cabo de 13 días podamos las hojas de cada plántula  y las mantuvimos in Vitro para la recuperación de adultos. La introducción de los parasitoides se hizo de acuerdo al momento más adecuado de su huésped que es cuando las larvas del minador están en el primer o segundo instar, evento que ocurre entre los tres y siete días post-oviposición. En promedio se recuperaron 4 ± 0.25 ( µ ± SEM) adultos del parasitoide por cada hembra introducida.  La recuperación de los adultos del parasitoide estuvo muy por debajo de lo esperado.  La capacidad reproductiva del parasitoide bajo las condiciones de este estudio nos obliga a repensar la viabilidad de un programa de control biológico por incrementación utilizando a Mirax insularis como agente de biocontrol.

Palabras clave: Mirax insularis, Coffea arabica, minador del café

Poster #53

Extracts of Native and Non-Native Plant Species for the Control of Cogongrass (Imperata cylindrica L). 

Lissa D. Reid and Oghenekome U.Onokpise, Florida A&M University, Tallahassee, Florida. Lissa1.reid@famu.edu

One of the most invasive species in Florida and other Gulf Coast States is Cogongrass. Cogongrass pose a major problem in natural habitats, on forested lands, rights-of-way and interstate highways. The present study was undertaken to evaluate the performance of cogongrass when grown in extracts of muhly grass and chenopodium. Genets and ramets of cogongrass were transplanted into magenta vessels containing 50% solution of root and shoot extracts of muhly grass and chenopodium, and placing magenta vessels in a growth chamber maintained at 28^oC, at a 16/8hour photoperiod and a relative humidity of 55 %. The genets and ramets of cogongrass were evaluated one per week for shoot and root growth, as well as rhizome extension after transplanting. Preliminary results show that the extracts of muhly grass and chenopodium reduced shoot growth and rhizome extension of cogongrass. The muhly grass shoot extracts along with the chenopodium extract were the most effective in reducing the performance of cogongrass compared to muhly grass and chenopodium root extracts. Root: shoot ratios of cogongrass also decreased by 50-70%. Thus, muhly grass and chenopodium extracts may contain some allelochemicals that could impact the invasiveness of cogongrass.

Keywords: weed control, muhly grass, chenopodium, allelochemicals

Poster #54

Evaluation of Acibenzolar-S-Methyl, PGPR and Silicon for Their Effects on Growth and TYLCV of Tomato

Shouan Zhang, Thomas L. White and Waldemar Klassen. Tropical Research and Education Center, University of Florida, IFAS, Homestead, FL 33031. szhang0007@ufl.edu

Greenhouse and field trials have been conducted to evaluate acibenzolar-S-methyl (ASM; Actigard 50WG, 30 and 3 mg/l), plant growth-promoting rhizobacteria (PGPR; SE34 and IN937b, 10⁷ CFU/ml), and silicon (silicic acid, 1.5 and 0.15 mM) on their potential to enhance plant growth and to suppress tomato yellow leaf curl virus (TYLCV).  In the greenhouse assay, four applications of the inducers were applied weekly as soil drenches from 1 week after planting (WAP).  Treatments were arranged as randomized complete blocks with twelve replications for each treatment and one plant per replication. Compared to the nontreated control, all treatments except for ASM at 30 mg/L significantly (P<0.05) increased plant height by 6 WAP; treatments with PGPR and silicic acid at both test concentrations significantly (P<0.05) increased stem caliber; and PGPR strain IN937b significantly (P<0.05) increased the chlorophyll content in tomato leaves.  For TYLCV infection, one plant from each treatment was placed in a cage for 1 week containing viruliferous whiteflies. Tomato plants were then transferred onto greenhouse benches for 2.5 weeks when the severity of TYLCV disease was rated.  All treatments significantly (P<0.05) reduced TYLCV disease compared to the nontreated control.  For the field trial, tomato seedlings treated with the same inducers 2, 3 and 4 WAP were transplanted into the field bed 5 WAP.  Two more applications by soil drenches were applied at 1.5 and 2.5 weeks after transplanting (WAT).  A randomized complete design was employed with four replicates for each treatment and fifteen plants for each replicate. Tomato plants were naturally infected with TYLCV by whiteflies.  Severity of TYLCV disease was rated at 4 WAT.  ASM at 3 mg/l significantly (P<0.05) reduced disease severity compared to the nontreated control. Results from our greenhouse and field studies suggest that ASM, PGPR and silicic acid could be incorporated in integrated strategies for control of TYLCV of tomato.

Keywords:  tomato, TYLCV, induced resistance

Poster #55

Evaluation of Triazole and Strobilurin Fungicides, Alone and in Combination, for Control of Exserohilum turcicum on Sweet Corn

Richard N. Raid, Everglades Research and Education Center, University of Florida, IFAS, Belle Glade, FL 33430. rnr@ifas.ufl.edu

Northern corn leaf blight, incited by Exserohilum turcicum, is one of the most important foliar diseases of sweet corn (Zea mays).  Causing large elliptical lesions that may coalesce and result in significant levels of leaf necrosis, fungicides are frequently relied upon for control.  Two field experiments were conducted in south Florida during Spring 2008 to evaluate the efficacy of several triazole and strobilurin fungicides, alone and in pre-mixtures, for control of this fungal pathogen.  The experimental design consisted of four replications of ten fungicide treatments arranged in randomized complete blocks.  Experimental units were composed of two rows, 9 meters in length, separated by three non-sprayed guard rows.  Fungicides were applied using a CO₂ backpack sprayer equipped with a 3-nozzle handheld boom.   Fungicides investigated included the strobilurin compounds azoxystrobin, pyraclostrobin, and trifloxystrobin, as well as the triazole compounds metconazole, propiconazole, prothioconazole,  and tebuconazole, either alone or in combination.  The  broad spectrum protectant maneb was also included.  Northern corn leaf blight was severe in both experiments, along with southern corn leaf blight in one of the trials.  Both trials were considered definitive.  All fungicide treatments provided for significant levels of disease control, with triazole and strobilurin fungicides proving significantly better than maneb.  In both trials, fungicides containing a triazole, either alone or in combination, were more efficacious than fungicides containing only a strobilurin compound.  These results emphasize the benefits of including triazole chemistries in a foliar disease management program on sweet corn, particularly if northern corn leaf blight is the featured disease.  Triazole/strobilurin pre-mixtures, or rotations of triazoles with strobilurin fungicides, would likely be the best candidates for controlling the prevalent sweet corn disease complex that includes the foliar blights and rust, since the strobilurins are excellent rust control fungicides.

Keywords:   Sweet corn diseases, fungicidal control, northern corn leaf blight

Poster #56

Educational Efforts Enhance Diagnostic Capabilities in the United States and the Caribbean Region

Amanda  Hodges¹, Greg Hodges², and Russell Duncan³, ¹Entomology and Nematology Department, University of Florida/IFAS, ²Florida Department of Agriculture and Consumer Services, Division of Plant Industry, and ³USDA, APHIS, International Services.  achodges@ufl.edu

The introduction of invasive, exotic arthropod species continually threatens US and Caribbean agriculture, forests, and other natural areas.  Undetected pest species have the potential to cause major economic damage to a local economy or result in trade implications for producers.  The warm, tropical climate of the Caribbean Region and the southern US are particularly vulnerable to new pest establishment.  Proper pest identification is critical to the early detection of threatening invasive, exotic arthropod pests.  The Southern Plant Diagnostic Network (SPDN), coordinated through the University of Florida/IFAS has coordinated and/or partnered with other organizations in order to provide advanced taxonomic training to US and Caribbean scientists from 2004-08.  Topics for SPDN education program have include Hemiptera (Auchenorrhycha, Sternorrhycha), the pink hibiscus mealybug (Maconellicoccus hirsutus), Coleoptera (Chrysomelidae, Scolytinae, and Cerambycidae), and invasive species of relevance to the southern US.  USDA-APHIS, International Services provided lead coordination for Caribbean workshops in partnership with the Inter-American Institute for Cooperative Agriculture (IICA), Barbados Ministry of Agriculture, and Ministry of Agriculture in Jamaica.  Scale insects and mealybugs (Hemiptera:  Coccoidea), a particularly problematic taxon in terms of identification and potential status as an invasive or actionable pest, were the focus of the Caribbean training workshops (2007-08).  Workshop outcomes for both US and Caribbean training sessions generally included 1) an increase in technical skill and confidence for genus, and in some cases species-level, determinations of fairly complex taxa groups 2) follow-up communications with specialist instructors and 3) early pest detections and/or new pest detection reports.

Keywords:  Invasive species, SPDN, diagnostics, USDA, APHIS, entomology identification, Coccoidea, scale insects, mealybugs

Poster #57

Response of the Melon Thrips, Thrips palmi Karny, and the Chilli Thrips, Scirtothrips dorsalis, to some Selective Insecticides

Dakshina R. Seal, Vivek  Kumar Jha, Waldemar Klassen and Catherine M. Sabines, University of Florida-IFAS, Tropical Research and Education Center, Homestead, FL 33031. vivekiari@ufl.edu

The melon thrips and the chilli thrips are important pests of fruit, ornamental and vegetable crops.  The melon thrips is very difficult to control.  None of the currently registered insecticides provide satisfactory control of this pest. On the other hand, insecticides of various classes provide satisfactory control of chilli thrips. Neonicotinoid insecticides are effective in controlling chilli thrips; but provide insignificant reduction of melon thrips.  Pyrethroid insecticides are not effective against the melon thrips nor rhe chilli thrips.  Spinetoram and Spintor have provided significant reduction of populations of both thrips species.  However, these insecticides showed reduced levels of control of the melon thrips in our recent studies conducted in 2008.  Spinetoram (8.0 oz/acre) in combination with Dyne-Amic (0.25% v/v; nonionic organosilicone surfactant) provided better reduction of both thrips than when Spinetoram was used alone. We also investigated two new Insecticide chemistries, Rynaxypyr™ and Cyazypyr ™ for the control of melon thrips and chilli thrips.  In our preliminary study, we did not record any significant reduction of thrips populations when these products were applied as a soil drench. Voliam flexi™, a premix product containing Coragen® and Actara® provided significant reduction of chilli thrips. Our main focus of this study was to use Spinetoram in rotation with other effective products to develop a lasting management program against melon thrips and chilli thrips.

Keywords: melon thrips, chilli thrips, chemical insecticides, reduced control of melon thrips

Poster #58

Development of IPM Field Guides for Coffee, Citrus, Plantain and Banana

Ada N. Alvarado Ortíz, Crop Protection Department, University of Puerto Rico, Mayagüez Campus, aalvarado@uprm.edu

The nature of tropical agriculture in Puerto Rico is one of a multiplicity of crops, most of these grown in small farms, threatening by a diversity of pests and diseases that impact crop production, causing economic loss to their producers.  Coffee, Plantain, Banana and Citrus are commodities of great economic importance in Puerto Rico Agriculture.  During year 2004 - 2005 altogether contributed with 130 millions to the agricultural income, in approximately 105,746 acre devotes to them.  The great variety of pests and diseases that our tropical environment sustains and the agronomic intensive practices carried out by growers in their farms makes necessary a new vision in keeping them informed and updated in the identification and pest management strategies.

In an effort to assist growers, Extension personnel and other agricultural educators, IPM Field Guides for Coffee, Citrus, Plantain and Banana were developed to help in the fast and accurate identification of pests and diseases. The main goal is to promote the adoption and implementation of effective strategies responding to specific needs of growers working with management of pests in crops of major importance in the Island. The guides are available at no cost online at http://academic.uprm.edu/aalvarado. The guides are for field use by a wide range of people, they carry descriptions and color photographs of fungal, bacterial and viral diseases as well as arthropods. Also, include a narrative section with the description and development of symptoms and information about how to identify key pests and diseases.

The educational materials created under this project complement the ongoing pesticide safety and IPM programs in Puerto Rico.  The outcomes of this project will lead to minimize the impacts and reduce the potential of pests in plantain and banana, citrus and coffee.

Keywords: field guides, pest, diseases

Poster #59

Erythrina Gall Wasp, Quadrastichus erythrinae (Hymenoptera: Eulophidae), a Pest of Coral Trees (Erythrina spp.) Recently Found in the Western Hemisphere.

Forrest W. “Bill” Howard, University of Florida, IFAS, Fort Lauderdale Research & Education Center, 3205 College Avenue, Fort Lauderdale, Florida, 33301 USA. FWHOWARD@UFL.EDU

Various species of the coral tree genus, Erythrina (Fabaceae), are grown as shade trees and for soil improvement in coffee and cacao crops in the American Tropics. The Erythrina gall wasp, Quadrastichus erythrinae Kim (Hymenoptera: Eulophidae), believed to be native to Africa, was recently spread to localities in Asia and Oceania where its galls have seriously damaged coral trees of various species. The insect was first found in the Continental US in Miami-Dade County, Florida, in October, 2006. Five months later, we observed galls on foliage of E. variegata growing 65 km north of the former site and reared Q. erythrinae from the galls. We began field observations of Q. erythrinae to determine characteristics of its damage, its host preferences among Erythrina spp., and characteristics of its population dynamics and dispersal behavior. The gall wasps showed a marked tendency to remain close to their natal host tree and attack it repeatedly, rather than disperse from it, yet they nevertheless found and infested isolated Erythrina plants. Erythrina spp. appeared to have pronounced differences in susceptibility, with E. herbacea (native to Florida) highly resistant compared to several Eastern Hemisphere species upon which the wasps caused extensive galling. Massive galling of some Erythrina trees caused extensive defoliation and branch die-back, in some cases resulting in the death of the tree. The numbers of Erythrina gall wasps caught in traps in Erythrina trees and the incidence of galling on hosts fluctuated considerably during the one-year period of observation. Some trees of exotic Erythrina spp. survived almost total defoliation caused by galling, but recovered and currently have a low incidence of galling. The potential for Q. erythrinae to spread in the Caribbean Region, and preliminary research on management methods for this pest will be discussed.

Keywords: insect pests, invasive pests, crop shade trees.

Poster #60

Climate Factor Comparison Analysis for Red Palm Mite, Raoiella Indica

D. Borchert and D. Fieselmann, USDA, Plant Protection and Quarantine, Center for Plant Health Science and Technology, Raleigh, North Carolina, USA. Daniel.A.Fieselmann@aphis.usda.gov  

The red palm mite, Raoiella indica was first detected in the Western Hemisphere in Martinique in 2004.  It has rapidly spread through the Caribbean Basin causing extensive foliar damage, especially on young coconuts, other palms and bananas.  Red palm mite has been reported in Israel and Egypt for over 25 years without causing significant damage.  The aim of this study is to investigate the climatic factors that might explain the difference in pest status between the Mediterranean Region as opposed to the Caribbean Basin.  The web based NAPPFAST (North Carolina State University- Animal and Plant Health Inspection Service Plant Pest Forecasting) system was used to compare various climatic factors that may determine red palm mite populations.  Three climatic factors utilized in the analysis are present in the countries where R. indica is reported to be a pest.  This NAPPFAST model may be useful for predicting areas at high risk for red palm mite.  This model may also be useful to assess the risk from other pest species based upon climatic factors.   

Keywords: Raoiella indica, Climate matching, NAPPFAST

Poster #61

Tropical Race 4 of Panama Disease: A Dangerous Threat to Sustainable Production of Banana and Plantain.

Randy C. Ploetz, University of Florida, IFAS, Tropical Research & Education Center, 18905 SW 280^th Street, Homestead, FL 33031-3314 USA. RCPloetz@ifas.ufl.edu

Panama disease, aka fusarium wilt of banana, is caused by Fusarium oxysporum f. sp. cubense. A dangerous new variant of this pathogen, tropical race 4 (TR4), was reported in Southeast Asia in the early 1990s.  TR4 has since spread widely in that region, and represents a serious threat to banana production in the Americas.  Over 80% of the bananas that are produced worldwide are susceptible to this new race, including all commercial cultivars of the Cavendish subgroup, the plantain subgroup, important AAA and ABB cooking bananas, and diverse AA, AB, AAA and AAB dessert bananas.  TR4 could easily be moved to the Americas in infected plants and suckers, and would devastate dessert, plantain and cooking banana production wherever it established.  This poster outlines the nature and magnitude of the threat, measures that should be taken to exclude TR4 from the region, and strategies for containing the pathogen should it spread to the hemisphere.

Keywords: Cavendish subgroup, plantain subgroup, prevention of spread

Poster #62

Distribution and Host Associations of Proba distanti (Atkinson) (Hemiptera: Miridae), a Plant Bug recently Established in Florida

Thomas T. Dobbs¹, Thomas J. Henry² and Alfred G. Wheeler, Jr³.

¹Miami Plant Inspection Station, United States Department of Agriculture, Animal and Plant Health Inspection Service, Plant Protection and Quarantine; ²Systematic Entomology Laboratory, United States Department of Agriculture, Agricultural Research Service c/o National Museum of Natural History, Smithsonian Institution; ³ Dept. of Entomology, Soils and Plant Sciences, Clemson University. thomas.dobbs@aphis.usda.gov

The Neotropical plant bug, Proba distanti (Atkinson) (Hemiptera: Miridae), was first detected in Florida in 1990 in Palm Beach County.  Extensive surveys have revealed that it is now widely established throughout much of the Florida peninsula.  The majority of specimens were collected from two common herbaceous weeds that we consider primary hosts: ragweed (Ambrosia artemesiifolia L.) and dogfennel (Eupatorium capillifolium (Lam.) Small).  These weeds are common in open fields, disturbed sites, and along roadsides.  In Florida, their vegetative growing seasons do not generally overlap.  Ragweed is typically a spring and summer plant whereas dogfennel appears in the fall and persists through the winter. Colonization of ragweed by P. distanti normally begins in February and extends until host die-back, usually around September.  The bug then migrates to dogfennel, feeding on that host from late September through the winter months.  Ragweed and dogfennel support a rich diversity of heteropteran herbivores, but P. distanti can frequently be observed on each as the dominant mirid species.  Proba distanti is distributed in Florida from the southernmost county of Monroe throughout the peninsula as far north as Clay County, just northeast of Gainesville.  As a diagnostic aid, we provide redescriptions of the genus Proba and the species P. distanti, along with a checklist of the North American species and their distributions.

Keywords:  Proba, Florida, exotic species

Poster #63

Evaluation of Pathways for Exotic Plant Pest Movement into, within, and out of the Greater Caribbean Region

Heike Meissner, Christie Bertone, Lisa Ferguson, Andrea Lemay, and Kimberly Schwartzburg. USDA-APHIS-PPQ-CPHST, Plant Epidemiology and Risk Analysis Laboratory, 1730 Varsity Drive, Suite 300, Raleigh, NC 27606. Heike.E.Meissner@aphis.usda.gov

The purpose of this poster is to introduce the project “Evaluation of pathways for exotic plant pest movement into, within, and out of the Greater Caribbean Region”. This project is a collaborative effort between the Caribbean Invasive Species Working Group (CISWG) and the United States Department of Agriculture (USDA). The objective of this project is to contribute to an improved understanding of pathways of exotic pest movement as they pertain to the Greater Caribbean Region, thereby helping CISWG to enhance or refine the Caribbean Regional Invasive Species Intervention Strategy (CRISIS) for preventing the introduction or spread of exotic pests.

The scope of the pathway analysis includes nearly all countries bordering the Caribbean Sea and all terrestrial, non-vertebrate, plant pests. Among the pathways evaluated in the context of this project are: (i) airline passenger baggage, (ii) international mail, (iii) movement of people, (iv) maritime cargo, and (v) wood packaging material. Some of these topics are presented in greater detail as separate posters at this meeting.

Keywords: Caribbean Region, pathway analysis

Poster #64

Population Dynamics of the Red Palm Mite (Raoiella indica Hirst) and the Search for Sustainable Management Options in Jamaica

J. V. Goldsmith, and L. R. Myers, Research and Development Division, Ministry of Agriculture, Jamaica.  julietgoldsmith@gmail.com

The red palm mite (Raoiella indica Hirst), first detected in Jamaica in April 2007, has spread to several parishes, affecting coconut and ornamental palms, some severely. The search for sustainable management practices for the pest involved two initial studies: population dynamics including a hunt for natural enemies and the determination of an environmentally friendly treatment for coconut palm seedlings under nursery conditions.

The seasonal dynamics of Raoiella indica were studied between July 2007 and May 2008. The study was conducted in a commercial orchard, to which bi-weekly visits were made. Raoiella indica populations increased during dry periods, and declined during periods of persistent rainfall. Two predators; a phytoseiid mite (Amblyseius largoensis), and a thrips (Leptothrips sp) were found feeding on the red pal mite. Amblyseius largoensis was the most abundant predator. This predator and R. indica exhibited similar population fluctuations throughout the sampling period.

Twelve plots, each measuring 1m x 2m and containing 55 coconut palm seedlings (at the 6-leaf stage) were established in Spring Gardens, Portland and treated with six chemicals: abamectin, diafenthiuron, soybean oil, sulphur, insecticidal soap and spiromesifen.  The treatments were replicated two times in a randomized complete block design and included two unsprayed (control) plots. All the treatments were effective in reducing red palm mite populations. Insecticidal soap had the least impact on the predators (efficacy 53%). Thus low populations of Raoiella indica are favoured by high rainfall conditions and can be achieved by the application of select chemical treatments.

 Keywords: Raoiella indica, population dynamics,Jamaica

Poster #65

Management of Pink Hibiscus Mealybug (Maconellicoccus hirsutus Green) in Jamaica

Michelle A. Sherwood¹, L. R. Myers¹, M. Young², D. Robinson³ and J. Lawrence⁴. ¹Ministry of Agriculture, Research and Development Division, Plant Protection Unit;  ²Rural Agricultural and Development Authority (RADA); ³University of the West Indies, (Mona), Life Sciences Department, Entomology; ⁴Caribean Agricultural Research and Development Institute (CARDI). mishanton@yahoo.com

Pink Hibiscus Mealy Bug (PHMB), Maconellicoccus hirsutus Green, a polyphagous pest (>300 host plants) of economic and quarantine importance was first reported in Jamaica in June 2007.  As of May 2008 the PHMB infestation is limited to the parishes of Portland and Kingston. Containment and management of the pest is based on an integrated pest management programme involving primarily surveillance, biological control and cultural control components, underpinned by public education and awareness efforts.  Locally ornamentals, fruit trees, vegetables and weeds have been attacked by this pest. The parasitoid wasp Anagyrus kamali Moursi was sourced through the United States Department of Agriculture (USDA) and released at all infested sites. A total of 168,200 adult A. kamali were received between August 15, 2007 and May 13, 2008.  Pre-release monitoring was conducted at 12 sites in Portland and two in Kingston.  Monthly post-release monitoring continues by sampling Hibiscus plants to determine PHMB populations and parasitism levels.

Initial parasite recovery was observed within three months of the programme in Portland. After eight months the mean PHMB population at all monitoring sites in Portland had decreased by 75 - 100% of pre-release levels and 97-100% parasitism levels recorded at 50% of the sites in Portland and Kingston. In January 2008 resurgence in PHMB populations was observed at several sites however not up to pre-release levels. Local natural enemies observed include species of ladybird beetles, a predatory reduvid bug and a parasitoid wasp. The programme has proven effective to date by containing and reducing the PHMB population in the affected parishes with the PHMB remaining only an urban pest with little or no impact on agriculture and natural areas.

Keywords: Maconellicoccus hirsutus, biological control, Anagyrus kamali, Jamaica       

Poster #66

Purple Nutsedge Tuber Productivity as Affected by Organic Mulches in a Watermelon Production System

J. Pablo Morales-Payán ¹, Pedro Márquez-Méndez¹, Erin Rosskopf², Yasser Shabana³, Raghavan Charudattan³ and Waldemar Klassen⁴.

¹ Department of Horticulture, University of Puerto Rico - Mayagüez Campus, PO Box 9030, Mayagüez, PR 00681; ² USDA, ARS, USHRL, 2001 South Rock Road, Fort Pierce, FL 34945; ³ Department of Plant Pathology, University of Florida, 1453 Fifield Hall, PO Box 110680, Gainesville, FL 32611, and ⁴Tropical REC, 18905 SW 280 St., PO Box 111569, Homestead, FL 33031. jpmorales@uprm.edu

Research was conducted in Isabela, Puerto Rico, to determine the tuber productivity of the weed purple nutsedge (PN) and the yield of ‘Crimson Sweet' watermelon when grown with or without organic soil bed mulches [hays of millet (Pennisetum glaucum), nutsedge (Cyperus rotundus), sunnhemp (Crotalaria juncea), sorghum (Sorghum bicolor), cowpea (Vigna unguiculata), cogongrass (Imperata cylindrica), Bahiagrass (Paspalum notatum), and rye (Secale cereale)]. The mulches were set covering the top of the soil beds the same day the crop was established. Natural populations of PN were approximately 100 viable tubers per meter square. PN plants able to grow through the mulches were left unchecked until the end of the crop. Non-mulched weed-free checks were kept by weekly removal of emerging weeds. Plots infested season-long with PN were used as weedy checks. PN tuber production was significantly reduced when watermelon was mulched with Bahiagrass (68% lower), nutsedge (45% lower), gogongrass (36% lower), millet (36% lower), and sorghum (34% lower), as compared to PN-infested checks. When mulching with cogongrass and nutsedge, watermelon yield was significantly higher than with other mulches.

Keywords: Organic horticulture, vegetable crops, weeds

Research Funded by the T-STAR Program (UPR Project ZTS-36).

Poster #67

Effects of Altitude and Harvest Period on Broca (Hypothenemus hampei Ferrari) infestations in Coffee (Coffea arabica L.) Beans in the Dominican Republic. 

Yluminada O. López, Miguel M. Campo, and  José B. Nuñez. Crop Science Department, Universidad ISA, La Herradura, Santiago, Dominican Republic. jnunez@isa.edu.do; cdejesus@isa.edu.do

In the Dominican Republic, the area planted with coffee is 132,500 ha which produces an annual harvest of 36,636,364 kg through the efforts of more than 50,000 coffee farmers.  Since 1997, the broca (Hypothenemus hampei) pest has infested the coffee fields in the country and has reduced crop yield and quality.  The objectives of this study were to evaluate the influence of altitude and harvest period on the incidence of the broca incidence and on coffee bean grain quality. The experimental design was a completely randomized design with a factorial arrangement with 4 replicates.  The twelve treatment combinations were formed from four altitudes (400-500, 600-700, 850-950 and 1000-1100 meters) and three harvest periods (November, December and January).  The variables were crop management, percentage of infected grains, and commercial quality of the beans. The results showed that from 78.4% to 100% of the farmers controlled the shade at 850-950 meters of altitude while 74.75% did so at 400-500 meters of altitude.  The higher incidences (22.33 % and 20.00 %) of infected beans were at 400-500 and 600-700 meters of altitude, respectively. The lineal regression analysis showed an inverse relationship between altitude and percentage of infected grains. Moreover, this analysis showed a direct relationship between altitude and bean quality AAA, but an inverse relationship with quality AA and A. The highest percentage of beans with quality AAA (69.44 %) and AA (52.61 %) were at 1000 -1100, and 400-500 meters of altitude, respectively.   The data suggest that altitude affects the yield and quality of coffee beans.

Keywords: altitude, harvest periods, broca, coffee berry borer, bean,

Poster #68

Disease Management Programs for Basil Downy Mildew

R. N. Raid¹, P. Roberts², and P. Harmon³, Department of Plant Pathology, University of Florida, IFAS, ¹Everglades Research and Education Center, Belle Glade, ²Southwest FL Research and Education Center, and ³Dept. of Plant Pathology, Gainesville, FL  rnr@ifas.ufl.edu

During the summer of 2007, a severe foliar disease was noted on basil grown in south Florida.  The disease was characterized by foliar chlorosis, frequently delineated by leaf veination, with a light grey fungal growth evident on lower leaf surfaces.  Initially observed in the lower canopy, the disease subsequently developed in the mid to upper canopy.  Severely infected leaves frequently dehisced.  The disorder displayed fungal signs associated with downy mildew.  Crop losses in individual fields ran as high as 100%, with a number of basil shipments being rejected at delivery due symptom development in transit.   The performance of Koch’s postulates has verified the disease as being caused by a fungal species, most likely within the genus Peronospora.  To identify prospects for chemical control of this disease, a number of field experiments were conducted during fall 2007 through spring 2008.  Trials were conducted in commercial fields where basil was grown on 20-cm raised beds.  The crop was direct-seeded in four rows set on 25-cm centers, with an in-row plant spacing of approximately 2.5-cm.   The experimental design consisted of 3-4 replications of fungicide treatments arranged in randomized complete blocks.  Experimental units were composed of 4 basil rows, 4 meters in length, separated by 2-m non-sprayed buffer plots.  Fungicides were applied using a CO₂ backpack sprayer equipped with a handheld boom calibrated to deliver 580 l/ha at 2.1 x 10⁵ Pa.  High levels of natural inocula in the area and long dew periods created ideal conditions for downy mildew development.  Disease conditions were severe and all tests were judged definitive.  A number of different chemistries showed promise, among them various phosphonic compounds, mandipropamid, fenamidone, dimethomorph, propamocarb, and azoxystrobin.  Tank-mixtures, and/or alternations of phosphonic fungicides, with the aforementioned other chemistries, provided for excellent control when applications were initiated before disease onset and applied on a weekly basis. 

Keywords:  basil, downy mildew, fungicidal control

Poster #69

A New Lethal Disease of Syagrus romanzoffiana and Washingtonia robusta in Florida Is Caused by Fusarium oxysporum

Monica L. Elliott and E. A. Des Jardin, Fort Lauderdale Research and Education Center, University of Florida, Fort Lauderdale. melliott@ufl.edu

Syagrus romanzoffiana and Washingtonia robusta are popular landscape ornamental palms grown throughout most of Florida.  Since late 2004, we have noted mature specimens in the landscape and juvenile material in nurseries of S. romanzoffiana with symptoms not observed previously for this species.  Symptoms include premature necrosis of the oldest leaves, followed by the next younger leaves becoming chlorotic and necrotic, usually with only one side of the leaf exhibiting symptoms initially.  A distinct reddish-brown stripe is visible on the petiole and rachis, and there is a corresponding discoloration internally.  Within 2-3 months after onset of initial symptoms, the entire canopy desiccates and turns brown as if freeze-dried in situ.  Similar symptoms were observed on W. robusta beginning in the spring of 2007 in landscapes and a nursery.  This new disease has been observed from the center of the state (Tampa/Orlando) to the southern portion of the peninsula.  Fusarium oxysporum was consistently isolated from symptomatic petiole tissue from both palm species.  DNA was extracted from single-spore isolates, and a portion of the translation elongation factor 1-alpha (TEF) was amplified using the polymerase chain reaction and the ef1 and ef2 primers.  The resulting amplicons were sequenced.  Comparison of the sequences obtained with TEF sequences in the FUSARIUM-ID database (http://fusarium.cbio.psu.edu) demonstrated that this F. oxysporum was a new formae speciales. Koch’s postulates were completed using juvenile plants of S. romanzoffiana and F. oxysporum isolates obtained from S. romanzoffiana.  Koch’s postulates were also completed using S. romanzoffiana and W. robusta seedlings and F. oxysporum isolates obtained from both palm species.  F. oxysporum isolates from S. romanzoffiana were pathogenic on W. robusta, and, likewise, isolates from W. robusta were pathogenic on S. romanzoffiana.

Keywords:  Fusarium oxysporum, Syagrus romanzoffiana, Washingtonia robusta

Poster #70

In Vivo Study of Cogongrass (Imperata Cylindrica L.) Rhizome Production

Oghenekome U. Onokpise, James J. Muchovej, and Susan K. Bambo. College of Engineering Sciences, Technology and Agriculture, Florida A&M University, Tallahassee, Florida 32307. susan.bambo@famu.edu

Cogongrass is an aggressive, rhizomatous, invasive perennial grass that is scattered throughout the tropical and subtropical regions of the world, and has become a serious problem in Florida and other Gulf Coast States. A greenhouse study was conducted to evaluate the growth and spread of rhizomes of grass species grown in combination with other native grass species. Native grass species used included: switchgrass (Panicum virgatum L), maidencane (Panicum hemitomon Schult.), and muhlygrass (Muhlenbergia capillaries (Lam) Trin.). All plants were raised in tubbets and then transplanted to 7.6 L greenhouse pots in different combinations with cogongrass. Data on rhizomes of cogongrass and maidencane (rhizomatous species) were recorded during the harvest periods (6, 12, 18 or 24 weeks). The mean number and mean total length of cogongrass rhizomes ranged from 3 to 8 and 0.06 to 0.14 m at 6 weeks to 40 to 94 and 8.37 to 20.39 m at 24 weeks, respectively. Similarly, the mean number and mean total length of maidencane rhizomes ranged from 0.01 to 3 and 0.05 to 0.27 m at 6 weeks to 11 to 26 and 1.57 to 3.31 m at 24 weeks, respectively. There were 51 to 74% and 47 to 74% reductions in the mean total length of cogongrass rhizomes grown in combination than those grown individually at 12 and 18 weeks, respectively. The mean number of cogongrass rhizomes had 54 to 71% reductions when in combination than individually at 12 weeks. Likewise, at 18 weeks the mean number and mean total length of rhizomes of maidencane were reduced by 51 to 65% and 20 to 75%, respectively, when grown in combination with others grasses than alone. The number and spread of rhizomes explain cogongrass’ invasiveness and competitiveness. The reduction of cogongrass in combination with native species shows a prospect that some Florida native grasses could reduce the invasiveness of cogongrass in the Gulf Coast States.

Keywords: Cogongrass, rhizomes, native grasses

Poster #71

Natural Spread of Plant Pests into and within the Greater Caribbean Region

Christie Bertone and Heike Meissner. U.S. Department of Agriculture, Raleigh, NC; Heike.E.Meissner@aphis.usda.gov; Christie.A.Bertone@aphis.usda.gov

The natural spread of exotic organisms mediated by wind, water, and inter-island movement of birds and other animals may play a significant role in the movement of pests throughout the Caribbean Region. Biological and atmospheric events and processes often interact to facilitate the aerial dispersal of plant pathogens, insects, mites and other organisms over long distances and wide areas. The objective of this study was to review the most current scientific literature to answer questions relating to the natural spread of exotic plant pests into, within, and out of the Greater Caribbean Region, e.g., whether it occurs, patterns of movement, types of pests prone to natural spread, and what methodologies could be employed to reduce the likelihood of establishment. Our results indicate that it is very likely that a few significant plant pathogens have migrated from Africa into the Caribbean through wind dispersal, and that a substantial level of wind-assisted dispersion and migration of plant pests between the various islands and continents in the Greater Caribbean is occurring on an ongoing basis.  Many insects are capable of long-distance flight and this ability, assisted by wind, allows them access to new territories. Wingless or immature insects, insects incapable of long distance flight, and arthropods are frequently wind-dispersed as well. Countering natural dispersion and migration can be accomplished primarily through stringent surveys, assisted by predictive modeling.  Knowing what pests are capable of establishing and causing economic damage within a given area, and early intervention if and when a pest invades the Caribbean Region may reduce the likelihood of establishment.

Keywords: Natural spread, wind-dispersal

Poster #72

Wood Packaging Material as a Pathway for Movement of Exotic Insect Pests into and within the Greater Caribbean Region

Heike Meissner, Tom Culliney, Andrea Lemay, Leslie Newton, and Christie Bertone.  U.S. Department of Agriculture, Raleigh, NC. Heike.E.Meissner@aphis.usda.gov

Wood packaging material (WPM), such as pallets, crates, and dunnage, is used all over the world in shipments of both agricultural and non-agricultural products. WPM has been recognized as a pathway for the spread of exotic pests, including arthropods, nematodes, mollusks, weeds, and plant pathogens. WPM is commonly produced from low-grade or scrap wood of multiple woody plant species, often with bark still attached. WPM is routinely re-used and re-conditioned, often making it impossible to determine its origin. Countries that have adopted the standard ISPM 15 of the International Plant Protection Convention now require WPM to be either fumigated or heat-treated prior to import. The U.S. began full enforcement of its requirements based on ISPM 15 on July 5, 2006. The objective of this study was to use data collected by the U.S. Department of Agriculture to discuss the role of WPM in the introduction of pest species into the Greater Caribbean Region. For both maritime and air cargo, significant differences were found between countries of origin in terms of the percentage of shipments that contain WPM. A list of species intercepted on WPM after full enforcement of ISPM 15, as well as list of species associated with WPM that have the potential to establish in the Greater Caribbean Region are presented.

Keywords: wood packaging material, Scolytidae, ISPM 15

Poster #73

Airline Passenger Baggage as a Pathway for Exotic Plant Pest Movement throughout the Greater Caribbean Region

Heike Meissner, Andrea Lemay, and Kimberly Schwartzburg. U.S. Department of Agriculture, Raleigh, NC. Heike.E.Meissner@aphis.usda.gov

During the 20^th century, international air travel became the most important means of international travel. The large majority of all visitors to the Greater Caribbean Region -both from within and outside of the Caribbean- arrive by air. International air travel has long been considered a significant means of moving pest species.

The objectives of this study were to: a) use data collected by the United States Government to estimate plant quarantine material (QM) approach rates (the percentage of sampling units containing QMs) and the annual number of plant QMs entering the United States in airline passenger baggage; b) discuss how plant QM approach rates relate to pest risk; and c) to explore how this data may be applicable to other countries of the Greater Caribbean Region.

The study concluded that international airline passenger baggage may be an important pathway for exotic species movement. In the case of the United States, the risk from international airline passenger baggage can be mainly attributed to travelers who are visiting family or friends, while tourists or business travelers present a far smaller risk.  For most other countries of the Greater Caribbean Region, the majority of all visitors are tourists; and even travelers in the “visit family” and “visit friends” category probably do not present an equally high level of risk as to the United States. Given the relatively low interception efficiency of port inspections, it is unlikely that the existing pest risk can be mitigated effectively by inspection alone. This would be especially true for countries that have a small number of inspectors and high numbers of incoming travelers.

 Keywords: air travel, approach rate, interception efficiency

Poster #74

Likelihood of Hitchhiking Pests being Moved into and within the Greater Caribbean Region

Andrea Lemay and Heike Meissner. United States Department of Agriculture, Raleigh NC. Heike.E.Meissner@aphis.usda.gov

Pests may move to new environments in the Greater Caribbean Region by many means, or pathways. This study examined the movement of plant pests as “hitchhikers” in trade. In the context of this study, a hitchhiker pest is defined as an agricultural pest organism moving in or on a commodity which is not one of its hosts, or on or in a conveyance (airplane, ships) or shipping container. Hitchhikers may get into or onto commodities, conveyances or containers either by chance (e.g. nematodes in soil contaminations on truck tires) or -more commonly- because they are attracted by certain physical or chemical conditions to the commodity, conveyance or container. For example, flying insects may be attracted by airplane lights during nighttime loading; insects or mollusks may find shelter on or in cargo containers; etc. Pests that were originally associated with a shipment of a host plant may be left behind in a container or conveyance after unloading of the commodity, thus becoming hitchhiker pests.

This study examined USDA data, as well as data published in the scientific literature to address the frequency of hitchhiking pests, the likelihood of their survival in transit, and the likelihood of their escaping detection.

The study concluded that most insects, mollusks, weed seeds, and plant pathogens are likely to survive cargo hold conditions in aircraft, corroborated by the interception of over 1,000 live quarantine-significant hitchhiker pests at US airports since 1990.  Pests are very likely to escape detection. Even though the overall incidence of hitchhiker pests may be low, the immense number of conveyances and containers being circulated in international trade make this pathway one that presents a high risk but is difficult to control.

Keywords: hitchhiker pest, quarantine species, pathway

Poster #75

Control of Broad Mite, Polyphagotarsonemus Latus and the Whitefly, Bemisia tabaci, in Open Field Pepper and Eggplant with Predaceous Mites

José Castillo and Philip A. Stansly. University of Florida/IFAS

Southwest Florida Research and Education Center, Immokalee, Florida 34142.  jacastil@ufl.edu; pstansly@ufl.edu

The broad mite, Polyphagotarsonemus latus (Banks), and the sweetpotato whitefly, Bemisia tabaci (Gennadius), are serious pests of pepper and eggplant in Florida and elsewhere.  In greenhouse-grown pepper, both pests have been controlled by Ambylseius swirskii and broad mite has been controlled by A. cucumeris; however, there have been no reports regarding the effectiveness of these Phytoseiid mites in open field pepper or eggplant.  We evaluated both predaceous mite species in eggplant and ‘Serrano’ pepper in experimental plots in southwest Florida, and also assessed control of broad mite in ‘bell’ pepper on a commercial farm in the same region.  Both mites controlled broad mite on both crops, although fewer releases were necessary and better control was achieved with A. swirskii than with A. cucumeris.  In addition, A. swirskii controlled B. tabaci which is an especially important pest of eggplant in this region.  Both pepper and eggplant receiving A. swirskii yielded significantly more fruit than untreated plants or even eggplants receiving two acaricide sprays in 2007.  However, the cost of releasing A. swirskii in eggplant exceeded average insecticide costs by a factor of 2 or more.  Furthermore, A. swirskii did not provide adequate control of the spider mite, Tetranychus urticae Koch, another important pest of this crop in south Florida.  Therefore, further research is warranted to define lower effective rates of A. swirskii and combinations with spider mite specific predators.

Keywords: Phytoseiid mites, cost Tetranychus urticae, release rates

Poster #76

Demonstrating Integrated Pest Management of Hot Peppers

Jesusa Crisostomo Legaspi¹, Cassel Gardner¹, Gilbert Queeley², Norman Leppla¹, and James Cuda³. [1] USDA-ARS-CMAVE, Florida A&M University-Center for Biological Control,6383 Mahan Drive,Tallahassee, FL 32308; 2 Florida Cooperative Extension Service, CESTA, Florida A&M University, Tallahassee, FL 32307; 3 Entomology and Nematology Department, University of Florida, IFAS, Gainesville, FL 32611. slegaspi@gmail.com

We studied the effects of organic and synthetic chemical fertilizers on crop growth, yield and associated insect pests for two varieties of hot pepper, Capsicum chinense Jacquin (Solanaceae): “Scotch Bonnet” and “Caribbean Red” in north Florida. Hot peppers were grown under three treatments: poultry manure; mushroom compost; or “Growers’ Practice”, (conventional pesticides and chemical fertilizers), with equivalent amounts of soil nutrients applied to all treatments. The Growers’ Practice treatment permitted use of conventional insecticides if insect pests exceeded economic thresholds. Plant height and canopy diameter were significantly greater in the mushroom compost treatment for Scotch Bonnet; however, yields were not significantly affected by treatment or variety. The Growers’ practice treatment resulted in lowest plant height in Caribbean Red. The dominant insect pests found were the silverleaf whitefly, Bemisia argentifolii Bellows and Perring (Hemiptera: Aleyrodidae); green peach aphid, Myzus persicae (Sulzer) (Hemiptera: Aphidae); bandedwinged whitefly, Trialeurodes abutilonea (Haldeman) (Hemiptera: Aleyrodidae); and western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae). Significantly more insect pests were found on Caribbean Red than on Scotch Bonnet, but in none of the treatments did pests reach economic injury levels. Results indicate that hot peppers may be grown without using insecticides in north Florida because insect pests did not reach levels high enough to affect yield. Furthermore, the crops may be grown using relatively inexpensive organic fertilizers because the use of synthetic chemical fertilizers does not result in higher yields. We found that organic methods can be profitable for growers in Florida provided pests remain below economic threshold levels.

Keywords: poultry manure; mushroom compost, organic fertilizers, economic thresholds

Poster #85

CIRAD Invasive Species Initiatives in the Caribbean Basin

Emmanuel Wicker¹, Catherine Abadie², Jean Heinrich Daugrois³, Luc Baudouin⁴, Michel Dollet⁴, Claude Vuillaume² and Pierre-Yves Teycheney².¹CIRAD-UR 27, PRAM, 97285 Le Lamentin Cedex 2,  Martinique, FWI; ²CIRAD-UPR75 & CIRAD-DG, Station de Neufchateau, 97130 Capesterre Belle-Eau, Guadeloupe, FWI; ³CIRAD-UPR75, Station de Roujol, 97170 Petit-Bourg, Guadeloupe, FWI ; ⁴CIRAD-UPR29, Campus international de Baillarguet - TA A-29 / F - 34398 Montpellier Cedex 5. Author for correspondence : teycheney@cirad.fr

CIRAD has developed several initiatives on invasive plant pathogens that are present in the Caribbean. These initiatives are primarily focused on Ralstonia solanacearum, Black Sigatoka, coconut lethal yellowing and viral diseases of sugarcane and banana. They include research activities, transfer of diagnosis techniques to plant protection and quarantine services, and participation to surveillance networks, either existing or under construction.

Epidemiological studies are the key component of many of our research activities, which are often carried out in the frame of collaborative projects. This is best illustrated by the surveys that were recently carried out in Grenada and that are in progress in St. Vincent on banana Moko disease (Ralstonia solanacearum race 2). Epidemiological studies were also carried out in Guadeloupe and Martinique on several pathogens affecting sugarcane, such as sugarcane yellow leaf virus and leaf scald disease, and on banana streak viruses. Likewise, surveys were carried out in St. Lucia, St. Vincent, Dominica and Suriname in order to confirm the presence/absence of Black Sigatoka, and in most Caribbean islands for characterising recent disease foci of coconut lethal yellowing.

Diagnosis and monitoring tools and techniques are one of the major outputs of our research activities. Transfers of these tools and techniques towards plant protection and quarantine services of Caribbean countries are achieved through collaborative projects and courses.

CIRAD also plays an active role in several projects and global surveillance networks such as PANDOeR and the current initiatives for promoting plant health in the Region. Its current projects involve the development of a regional Black Sigatoka surveillance and control network and a participatory database on major diseases of banana, coconut, horticultural crops, sugarcane and yam.

Keywords: epidemiological surveys, surveillance and control network, participatory database, Ralstonia solanacearum, Black Sigatoka, coconut lethal yellowing, viral diseases of sugarcane and banana

Food Science and Postharvest Technology

Poster #77

Biogas Production from Rice Hulls and Straw Treated with Urea.

Amarely Santana, Jerry Gabriel, Pascal Fenelus, Eliezer Louis, Juguette Badette, and Carlos Miguel De Jesús Arias. Animal Science Department; Universidad ISA, La Herradura, Santiago, Republica Dominicana.   asantana@isa.edu.do;  amasant20@yahoo.com.mx; cdejesus@isa.edu.do; car1070@yahoo.com

Rice production of the Dominican Republic is around half million of metric tons per year, 50% of which is crop residues (hulls and straw). This high production of fiber is used as feed, poultry bedding and organic fertilizer. Given that this large quantity of fiber could serve as a very good feedstock for biogas production, ISA University faculty setup two 60-day trials to evaluate the biogas yields using the two component substrates of rice crop residue (hulls and straw). The treatments consisted of either rice hulls or straws treated with urea and rabbit urine or with fresh bovine manure under environmental conditions. Each trial had a randomized design, however, the rice hull trials each involved two treatments and three replications, and the straw trials each had four treatments with three replications. The evaluated variable was the biogas production (dm³) per kg of DM in 10 d periods. The rice hulls treated with rabbit urine yielded about 57.38 dm³ /kg DM in 60 d and the rice straws treated with rabbit urine and bovine manure yielded 98.28 dm³ /kg DM.  From these trials we conclude that it is possible to produce a good yield of biogas per kg of DM from rice crop residues with a small-scale artisanal biodigester.

Keywords: crop residues, rice, biogas, yield.

Poster #78

Clarification of Guava (Psidium guajava L) Juice with Bioguavase Enzyme

María L. Plaza¹ and Murat Balaban¹, ¹University of Florida, Gainesville, FL

mlplaza@ufl.edu

Fruit juices are an important part of our diet. Guava (Psidium guajava L.) is a delicious, healthful tropical fruit that has not been used as processed juice. One of the challenges in processing guava juice is cloudiness due to suspended complex carbohydrates in the end product. Clarification of the juice is desirable in order to enhance consumer acceptability. Enzyme treatment is one method of enhancing the removal of suspended solids. Bioguavase is a commercially available pectinolytic enzyme system containing a variety of carbohydrase enzymes derived from Aspergillus niger. Our objective was to determine the optimal treatment time and concentration of Bioguavase for treatment of guava juice to obtain a clarified product. Four treatment times (3, 6, 9 and 12 hours) and three enzyme concentrations (400, 600 and 800 ppm) were tested in a repeated measures design at 30^o C. Following treatment, juice was clarified by centrifugation and analyzed for vitamin C content (2,6-dicloroindophenol titration method), antioxidant capacity (ORAC), total soluble phenolics, turbidity and color. After 3h reaction time, the 800 ppm treatment produced the clearest juice. Juice yield did not show significant differences (α = 0.05) at 600 and 800 ppm of enzyme concentration when the reaction time was extended beyond 13h. All enzyme treatments reduced the antioxidant capacity (between 17 and 21%) and decreased the total soluble phenolic content (between 3 and 7%) of the juice. We conclude that treatment of guava juice with 600 ppm Bioguavase for 3h is suitable for obtaining clarified juice.

Additional studies should further characterize phytochemical modifications caused by the treatment. The yield of clarified juice is significantly affected by the temperature and time used for the enzyme treatment.  Increasing the temperature may produce a good clarified juice but may also reduce the phytochemical composition and ascorbic acid content due to oxidation.  Using 30^oC with the appropriate enzyme concentration and reaction time will help minimize the reduction of the phytochemical component.

Keywords: guava, clarified juice, enzyme treatment

Poster #80

Development and Evaluation of a Ready to Cook Vacuum Packaged Goat Meat Product

N. Djeri¹, S. K. Williams¹, R. Mobley², A. McKenzie-Jakes², K. Sarjeant¹, A. Ruiz¹, ¹Department of Animal Sciences, University of Florida, Gainesville, FL and ²Florida Agricultural & Mechanical University, Tallahassee, FL. noufoh@ufl.edu

The objective of this study was to develop a goat meat rib product.  Four product prototypes were developed containing either all goat meat ribs, no additives and marinated in water (control) (Treatment 1); goat meat ribs marinated in water and apple cider vinegar (Treatment 2); goat meat ribs marinated in water only and manually rubbed with a spice blend (Treatment 3); and goat meat ribs marinated in apple cider vinegar and water and manually rubbed with a spice blend (Treatment 4). The products were vacuum-packaged and stored at 4 ± 1^oC for 21 days. Sensory evaluation using a trained sensory panel, microbiological analyses, pH and processing yields were determined from 0 to 21 days storage. The panelists detected no significant differences (P > 0.05) in overall tenderness between the four treatments. The goat meat ribs formulated with apple cider vinegar only were rated significantly higher (P < 0.05) for goat flavor intensity and off-flavor, when compared to all other treatments. Staphylococcus aureus, Salmonella spp., Escherichia coli O157:H7, generic Escherichia coli and fecal coliforms were not detected in any of the treatments. Total aerobic plate counts, total coliforms and anaerobic bacteria were significantly lower (P < 0.05) for goat meat ribs marinated with apple cider vinegar and ribs marinated with both apple cider vinegar and manually rubbed with the spice blend, when compared to ribs marinated with water only, and ribs marinated with water only and manually rubbed with the spice blend. Psychrotrophic counts were significantly lower (P < 0.05) for ribs marinated with apple cider vinegar and manually rubbed with the spice blend when compared to all other treatments. Results from this study suggested that marinating and applying a spice rub to goat ribs could produce an acceptable value added product.

Keywords: goat meat ribs, sensory analysis, psychrotrophs, coliforms

Poster #81

Relationship between Chlorophyll Fluorescence and Dry Matter Content of ‘Hass’ Avocado Fruit

J.A. Osuna-García¹, G. Doyon², I.J.L González-Durán¹, S. Salazar-García¹ and R. Goenaga³, ¹INIFAP-Santiago Ixcuintla Experimental Station. Santiago Ixcuintla, Nayarit, Mexico. ²Food Research and Development Centre, Agriculture and Agri-Food Canada, St. Hyacinthe, Quebec, Canada. ³USDA-ARS, Tropical Agriculture Research Station, Mayagüez, Puerto Rico. josunaga@tepic.megared.net.mx; osuna.jorgealberto@inifap.gob.mx

Mexico is the main ‘Hass’ avocado exporter in the world with more than 100,000 ton exported every year. Canada is an important importer country accounting for 12-15% of total exports from Mexico. Normally, from December to May exported fruit to Canada have very high dry matter content which is determined with a destructive and time consuming method. The objective of this experiment was to correlate skin chlorophyll fluorescence, as a non-destructive method, with dry matter content of ‘Hass’ avocado fruit. From December 2007 to April 2008, 10 fruit of five different skin color categories were collected monthly from a packinghouse in Michoacan, Mexico and rated using the following scale: 1 = fully green, 2 = <25% skin blackening, 3 = 26- 50% skin blackening, 4 = 51-75% skin blackening, and 5 >76% skin blackening. Two days after harvest, individual fruit were assessed for chlorophyll fluorescence using a modulated fluorometer, Model OS1-FL reporting fluorescence under steady state conditions (Fs), maximal fluorescence under steady state conditions (Fms), and quantum efficiency yield (Y). Immediately after reading fluorescence, fruit mesocarp dry matter content (DM) was determined using a microwave oven and values were correlated with fluorescence. Fs values varied from 147 to 292; FMS from 357 to 989 and Y from 0.504 to 0.818, while DM did so from 19 to 42%. The only fluorescence parameter that correlated significantly (P<0.001) with DM was Fs; however, correlation was low (r = - 0.31). This could be due to the relative high DM content of fruit (avg. 32.9%), which was much higher than the maturity standard (DM ≥ 21.5%). The results showed that chlorophyll fluorescence did not correlate with DM content of over-ripe avocado fruit. Efforts are underway to find out if fluorescence may be useful to predict legal maturity on unharvested ‘Hass’ avocado fruit.

Keywords: non-destructive, fluorescence, fruit maturity

Poster #82

Effect of Harvest Time and Ripening Degree on Quality and Shelf Life of ‘Hass’ Avocado

J.A. Osuna-García¹, G. Doyon², I.J.L González-Durán¹, S. Salazar-García¹ and R. Goenaga³, ¹INIFAP-Santiago Ixcuintla Experimental Station. Santiago Ixcuintla, Nayarit, Mexico. ²Food Research and Development Centre, Agriculture and Agri-Food Canada, St. Hyacinthe, Quebec, Canada. ³USDA-ARS, Tropical Agriculture Research Station, Mayagüez, Puerto Rico. josunaga@tepic.megared.net.mx; osuna.jorgealberto@inifap.gob.mx

Canada is an important avocado importer country accounting for 12-15% of total avocado exports from Mexico. ‘Hass’ avocado is harvested year round in the state of Michoacan. For most part of the season, fruit reach adequate mesocarp dry matter content (DM), ripen properly and consequently, quality and shelf life are excellent. However, after early January fruit DM content increases and skin blackening occurs. Shipments to Canada containing fruit with blackening skin have been rejected since this characteristic is sometimes associated with low pulp firmness and short shelf life. The objective of this experiment was to study the effect of harvest time and ripening degree on initial quality and shelf life of ‘Hass’ avocado. Fruit were harvested in October and December, 2007 and from January to April, 2008 and rated according to the following scale: 1 = fully green, 2 = <25% skin blackening, 3 = 26-50% skin blackening, 4 = 51-75% skin blackening and 5 > 76% skin blackening. At harvest, DM, skin color, pulp firmness, and pulp color were evaluated. Fruit were then refrigerated (6.0±1.0 ºC; 90±5% RH) for seven days to simulate terrestrial shipment to Canada. After this period, fruit were stored under market conditions (22±2 ºC; 75±10% RH) until they reached the edible ripening stage. Weight loss (WL), fruit with skin blackening, pulp firmness, and pulp color were determined every three days. Pulp DM, skin color and pulp color significantly increased with harvest time and degree of skin blackening. However, there were no significant differences for WL and firmness. Our results showed that there is no reason for Canadian retailers to reject fruit with blackened skin since fruit quality and shelf life were not affected by harvest time and degree of skin color.

Keywords: skin color, maturity index, firmness

Poster #83

Influencia del Clima, Riego y Época de Floración Sobre la Composición Nutrimental del Fruto de Aguacate ‘Hass’ en Michoacán

S. Salazar-García, M. Gallardo-Valdez y L.M. Tapia-Vargas, INIFAP-Campo Experimental Uruapan, Michoacán, México. E-mail: samuelsalazar@prodigy.net.mx

El objetivo de esta investigación fue evaluar el efecto del clima [semicálido subhúmedo (SS), semicálido húmedo (SH), y templado subhúmedo (TS)], la condición de humedad (con y sin riego) y época de floración que originó al fruto [“loca” (septiembre) y “normal” (enero)] sobre la composición nutrimental del fruto de aguacate ‘Hass’ en Michoacán. Se seleccionaron dos huertos de ‘Hass’ por cada clima y condición de humedad del suelo. En cada huerto se seleccionaron 10 árboles y cuando su fruto alcanzó la madurez legal (³ 21.5% de materia seca de la pulpa), de cada árbol y tipo de fruto (floración Loca o Normal) se cortaron cinco frutos de la misma edad para diseccionarlos en sus componentes (epidermis, pulpa, tegumento y cotiledones). El clima afectó la composición nutrimental de las partes del fruto. En la epidermis, los nutrimentos afectados fueron: N, P, Ca, Cl, Fe, Mn y B; en la pulpa: N, P, K, Ca y Mn; en el tegumento: S y Mn; en cotiledones: P, S, Cu, Mn y B. La condición de humedad del suelo tuvo poco efecto sobre la concentración de macronutrimentos en el fruto. En huertos sin riego, el fruto presentó mayores concentraciones de K, Ca, y S en la epidermis, de K y Ca en la pulpa y de Mg en el tegumento. El N y P no fueron afectados. En frutos de la floración Loca (cosechados en agosto) fue mayor la concentración de N (epidermis y pulpa), Ca (cotiledones), Mg (cotiledones)  y Zn (pulpa y cotiledones). En frutos de la floración normal (cosechados en octubre), solamente el N presentó mayor concentración en el tegumento.

Palabras clave: Persea americana, nutrición.

Poster #84

Development and Evaluation of Pre-Cooked Vacuum Packaged Goat Meat Products

N. Djeri¹, S.K. Williams¹, R. Mobley², A. McKenzie-Jakes², K. Sarjeant¹, A. Ruiz¹. ¹Department of Animal Sciences, University of Florida, Gainesville, FL and ²Florida Agricultural & Mechanical University, Tallahassee, FL. noufoh@ufl.edu

Production of value added pre-cooked goat meat products could increase demand, consumption, acceptability, and marketability of goat meat. The objectives of this study were to develop and evaluate proximate composition, pH, sensory and microbiological characteristics (fecal coliforms, aerobic plate counts, psychrotroph counts, anaerobic plate counts) of refrigerated pre-cooked vacuum-packaged goat rib products. Racks from ten Boer Crossbred Spanish meat goats were cut into three longitudinally proportional rib units, and randomly assigned to four groups and formulated with either 1) no treatment, control, 2) apple cider vinegar only, 3) Spice rub only or 4) spice rub plus apple cider vinegar. After formulation, all goat ribs were baked to an internal temperature of 74^oC in a conventional gas oven, vacuum packaged, and stored at 4 ± 1^oC for 42 days.

The trained panelists rated all samples slightly bland (4.00) to slightly intense (5.68). Overall, there was no significant difference (P > 0.05) between treatments through the 42 days shelf life for overall tenderness. Overall flavor of marinated goat rib with spice rub applied. The texture of both samples was similar (P > 0.05). The consumer panelists were also more likely to purchase the goat meat that had been marinated and a spice rub applied, over goat meat with a spice rub applied only. Psychrotrophic organisms counts varied from 0 to 5.95 log CFU/g: except for the spice rub, the data demonstrated a decrease in psychrotrophic organisms through 42 days for all treatments. No organisms of public health safety (Staphylcoccus aureus, Salmonella, Escherichia coli 0157:H7, and Listeria monocytogenes) were found. The trained and consumer panelists found the products acceptable, regarding goat flavor intensity, overall tenderness, and texture (consumer panel only). Manufacturing a pre-cooked marinated vacuum packaged goat rib product could be a successful venture.

Keywords: pre-cooked, goat ribs, vinegar

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