Agriculture and Plant Science.

Chair: Girish K. Panicker, Alcom State University

Vicechair: Juan L. Silva, Mississippi State University 

THURSDAY MORNING

Lamar I

8:45 Introduction

9:00 THE EFFECTS OF COGON GRASS AND NATIVE SHRUBS ON SEED AND BUD BANKS IN A LONG LEAF PINE SAVANNA

Shanise Brown (1)*, M. Effenik (2), and Joseph M. Wahome (1) Mississippi Valley State University (1), Itta Bena, MS 38941, and University of Mississippi (2), University, MS 38677

Cogon grass, Imperata cylindrica, is an invasive species in southeastern USA that reduces biological diversity in longleaf pine savannahs. The control of this species is difficult but important. A study to investigate the effects of invasive plants on seedling and bud banks was done to formulate ways of how to restore native plants. Experimental plots of burned cogon and andropogon grasses was compared with plots of unburned andropogon and yuapon holly in moist pine savannahs. Seed and bud banks in soils collected near and away from low shrub thickets in wet pine savannahs were also compared. Results showed that cogon grass had a negative impact on seedling emergence. There was a negative effect on sprout emergence. However, low shrub thickets did not have any significant effect on seedlings or sprout emergence. Implications of these findings will be discussed.

9:15 EVALUATING THE BIOLOGICAL ACTIVITY OF NATIVE DOGWOOD (CORNUS FLORIDA L.)

Greg Anazia *, E.M. Croom, Jr., and Ilias Muhammad, University of Mississippi, University, MS 38677

Dogwood has been traditionally used to treat infectious diseases including malaria and diarrhea. In the Southeastern United States, Dogwood has been reported to treat malaria by Native, European and African Americans. Cornus florida an official drug used similar to Peruvian bark (quinine) in the 1800s. The plant has been reported to contain a bitter glycoside corvine but no active compounds have been found to explain a rational use for the plant in treating malaria. In recent years, the plant has been considered to be only a weak astringent. The plant was also used in the 1800 to treat diarrhea and has been reported to be used as a laxative. Early investigations on C. florida revealed the presence of molluscicidal sarsapogenin, while the cytotoxic benzofuranone was isolated from C. controvera. The present study deals with the bioactivity-guided isolation of different collections of C. florida.

9:30 PRELIMINARY STUDIES IN CASTOR (RICINUS COMMUNIS) PRODUCTION FOR MISSISSIPPI

Jeremy T. Russell *, Robert D. Cossar, and Brian S. Baldwin, Mississippi State University, Mississippi State, MS 39762

Castor (Ricinus communis) is a cross-pollinated perennial grown as an annual in the U.S. Castor is cultivated mainly for its oil, used by industry and the military. Castor production decline in the 1970s however, recently it has made a resurgence due to renewed interest in its oil which in turn makes it a high value alternative crop. The objective of this study was two-fold; one to determine the optimum planting date for Mississippi, two to evaluate common herbicides for the effectiveness in castor along with its tolerance. The plantings were established at Memphis, TN; Starkville, Shubuta, and Poplarville, MS. Each field consisted of a RCB design with four replications of six planting dates. Experimental unit was two rows, 20' in length. Seed were harvested and yields assessed. Twenty herbicides (pre-and post-) were applied to twin rows of castor arranged in a RCB. Castor plants were assessed for injury fourteen and twenty-one days after spraying. Mississippi yields of castor were considerably less than the USDA predicted 1000 lbs/A. Earliest plantings were too early for maximum yield. Several herbicides were shown to be useful for weed control, while others will be useful in controlling volunteer castor.

9:45 AN ASSESSMENT OF THE ANTHROPOGENIC AND PEDOGENIC SOURCES OF ARSENIC IN SOILS THROUGHOUT MISSISSIPPI

Edward J. Foan * and William L. Kingery, Mississippi State University, Mississippi State, MS 39762

The objectives of the study were to collect historical and geological information pertaining to soil arsenic (As) inputs throughout the State of Mississippi. It is felt that the results of the study would be particularly useful to those in the fields of agriculture, civic planing and land remediation. Anthropogenic sources of As included arsenical biocides, applied mostly to cotton and fruit orchards, and poultry manure, containing the residues of arsenical growth promoters, applied to land as fertilizer. Estimates of total As loading on a county basis, from 1890 onwards, were calculated from acreage and livestock statistics from the Census of Agriculture and from historical accounts of recommended application rates. Geological As soil inputs were assessed for regions of the State using information from geological surveys and reported As compositions of minerals. The data will be presented in a tabular form as well as a series of maps, each of which will be divided into the State's 82 counties.

10:00 MEASUREMENT OF METABOLIC RATES OF KIDNEY BEAN SEEDS AND SEEDLINGS OF PHASEOLUS VULGARIS AT ROOM TEMPERATURE

Julius O. Ikenga * and Tracy M. Day, Mississippi Valley State University, Itta Bena, MS 38941

This research was undertaken to study the metabolic rates (mRs) of kidney bean seeds and seedlings of Phaseolus vulgaris at 24[degrees]C. Metabolic activities were measured using the direct respiratory technique. Fifty P. vulgaris seeds that were placed on four layers of water-drenched paper towels, in a bowl, were incubated and germinated in the dark. Seeds and, or seedlings were tested on a daily basis for two weeks. Prior to testing, each seed and, or seedling was blotted dry with a paper towel and transferred into a 250 ml Venier respirometer. The latter was fitted tightly with a Vernier Oxygen Gas Sensor Probe and then interfaced with a desktop computer. The computer was previously loaded with the Vernier Logger Pro[TM] Program. The Gas Sensor Probe was set to collect six samples per minute over a 10-minute period. Computer analyzed the initial data collected to determine metabolic rates (mRs). The control setup was treated the same as described above, except that the respirometer contained no seeds. Th e Day-0 seeds were not soaked in water prior to use as described above. We found that P. vulgaris seeds at Day-0 had a mR of 0.010% [O.sub.2]/min. at 24[degrees]C. The control setup registered 0.004% [O.sub.2]/min. while the germinating seeds and seedlings at Day-l to -13 registered mRs that ranged from 0.053% [O.sub.2]/min. to 0.092% [O.sub.2]/min. All phases of the test conducted showed evidence of metabolic activities.

10:15 FRESH-CUT SWEETPOTATOES: INFLUENCE OF PRESERVATIVES AND BLANCHING 

Hernan Cobo (1)*, Juan L. Silva (1), and James O. Garner (2), (1) Mississippi State University, Mississippi State, MS 39762, and (2) University of Arkansas at Pine Bluff, AR 71601

Unclean, cured sweetpotatoes (Ipomoea batatas) were dipped in water for 30 min and hand brushed. They were then dipped in a 50 ppm chlorine solution for 5 min, manually peeled and julienne sliced (40 x 3 mm). The sweetpotato sticks were sanitized (sprayed) with 40 ppm Tsunami 2008[R] solution sprayed at 155 psig for 5 min: The sticks were then dipped into five different preservatives for 5 min: (A) 2 % citric + 2 % ascorbic acids, (B) i % Fruit Fresh(r), (C) 50 ppm chlorine, (D) 100 ppm sulfite, and (E) water. A portion of sticks from each treatment was blanched in water at 90[degrees]C for 0 to 4 min. After blanching samples were tested for color and texture attributes. Blanching for one minute or more reduced shear values by 33 to 50%, making them unsuitable for fresh consumption. Blanching also seemed to lower brightness (Hunter 'L' value), whiteness and chroma. Hue was not affected by blanching. Preservatives had little if any influence on color and texture of sticks. Refrigerated, unblanched sticks main tained their color and texture for at least two weeks. The peracetic acid wash may aid in inactivating the browning enzymes.

10:30 REDUCTION OF LISTERIA MONOCYTOGENES ON HOT-SMOKED CATFISH BY POST-PACKAGING PASTEURIZATION 

T. Kim * and Juan L. Silva, Mississippi State University, Mississippi State, MS 39762

Listeria monocytogenes is a significant foodborne pathogen that is readily present on ready-to-eat (RTE) meats, including RTE seafood products, luncheon meat, hot dogs and deli meats. Post-packaging pasteurization was suggested as one way to reduce foodborne pathogens that contaminate meat after cooking. However, there is little or no published information concerning post-packaging pasteurization on Listeria monocytogenes in hotsmoked catfish. The objective of this study was to determine the effect of post-packaging pasteurization on hot-smoked catfish contaminated with Listeria monocytogenes. Listeria inoculated fish were subdivided into non-vacuumed and non-pasteurization (control), vacuum packaging only, or vacuum packaging plus pasteurization. For pasteurization, vacuum packaged fillets were submerged in 85[degrees]C water contained in a water bath for 1, 5, 10, and 15 min. After 1 day storage, each fillet was analyzed for water activity ([a.sub.w]), moisture content, salt, and Listeria monocytogenes cel l count. All smoked catfish samples had ranges of 0.91 to 0.86, 4.63% to 8.03%, 40.9 to 65.8%, and 7.55 to 16.4% for [a.sub.w], salt, moisture, and water phase salt, respectively. Vacuum treated fish without heat treatment showed 0.02 log reduction after 1 day storage while no survival of Listeria monocytogenes cells were detected on vacuum and heat treated fish for 10 min. This data indicated that postpackaging pasteurization processing might be an effective microbial intervention against Listeria monocytogenes on smoked catfish.

10:45 Break

11:00 Divisional Poster Session

EFFECT OF DIFFERENT CROPPING SYSTEMS ON VEGETABLE PRODUCTION

Franklin Chukwuma *, Patrick Igbokwe, and Liang C. Huam, Alcorn State University, Alcorn State, MS 39096

Intensive application of fertilizers, pesticides and other agrochemicals is now receiving wide attention with respect to the potential for contamination of soils, surface and groundwater. Hence, producing safe and nutritious food for the consumers, ensuring profitability of farming enterprises, and monitoring the viability of rural agricultural communities through environmental practices are some of the major challenges facing agriculture today. However, farmers experience some loss in yields after discarding synthetic inputs and converting their operations to organic production. Sustainable approaches that allow judicious use of synthetic chemicals may be more suitable start options especially for small farmers. Therefore, gradual switching from conventional to organic production so that the entire operation is not put at risk is very important. Hence, field experiments were conducted on McLaurin loam and Memphis silt loam soil during the summers of 2001 and 2002 to determine the effect of cropping systems ( conventional, transitional and organic) on sweet potato, tomatoes, bell pepper, and collard green growth and yield potential. Conventional cropping system involved mono cropping under the use of farm chemicals, while transitional and organic cropping systems involved crop (sweet potato, bell pepper and collard) intercropping under reduced-chemical and non-chemical input, respectively. Findings indicated that cropping system did not influence plant growth. However, marketable yield for sweet potato, bell pepper and tomatoes were higher for conventional cropping system while there was no yield difference on collard green due to the cropping system. Although yield were higher due to conventional cropping system, yield from the companion herbs when considered, overall yields from transitional and organic cropping systems will be compatible to conventional cropping system.

EFFECTS OF FDl41 AND ITS ANALOGS ON THE GERMINATION AND MORPHOLOGY OF SELECTED PLANT PATHOGENIC FUNGI

Maritza Abril (1 *), Kenneth J. Curry (1), and David E. Wedge(3), (1)University of Southern Mississippi, Hattiesburg, MS 39406, and (2)Natural Products Utilization Research Unit, USDA, ARS, University, MS 38677

A USDA experimental natural product fungicide referred to as FD141, and seven of its chemical analogs plus seven commercially available fungicides were evaluated for their ability to inhibit fiungal germination. Botrytis cinerea, Colletotrichum acutatum, C.fragariae, C. gloeosporioides, Phomopsis obscurans, and P. viticola were used for this purpose. ED 141 and the commercially available fungicides were effective germination inhibitors, while most FDl4l analogs were less effective. However, one of the experimental analogs, ED 142 (4-bromo FD141) caused anomalous development in germ tubes of three of the six fungi.

EVALUATION OF DIFFERENT TRELLIS-SYSTEMS FOR MALABAR SPINACH (BASELLA ALBA L.) PRODUCTION

O.P. Vadhwa (1 *), C.R. Reddy (1), James Spiers (2), and D.S. Marshall (2), (1)Alcorn State University, Alcom State, MS 39096, and (2)USDA Small Fruit Research Station, Poplarville, MS 39470

Malabar spinach (Basella alba L.) yield as influenced by four trellis systems was evaluated. Malabar spinach seeds were planted in the greenhouse and seedlings produced were used for this study and planted on May 15, 2002. From the limited data collected so far, it can be concluded that, Malabar spinach plants grown without trellis (control) were the least productive. Maximum yield was obtained with V-shaped trellis system followed by semivertical and vertical. Harvesting was more convenient with all trellis systems as compared to control where the plants were allowed to trail and spread on the ground. The first harvesting of spinach leaves was done on July 15,2002, and last harvesting was done on October 28, 2002. Plants are still healthy and growing well, harvesting will be continue till frost.

TOLERANCE OF IPOMOEA LACUNOSA TO VARIOUS CONCENTRATIONS OF CADMIUM IN MEMPHIS SILT LOAM SOIL.

M.S. Zaman (1 *), C. Davis (1), and P. Kumar (2), (1)Alcorn State University, Alcom State, MS 39069, and (2) Mississippi School for Mathematics and Science, Columbus, MS

The optimum growth period and the tolerance of Ipomoea lacunosa to soil cadmium (Cd) were evaluated with the help of four experiments. In experiments 1-3, plants were grown in the greenhouse. In experiment 4, plants were grown under laboratory conditions. In experiment 1, plants were grown in soils containing 0-5 00 ppm of Cd for 30 days. Results show that soil Cd at 250-500 ppm levels, do not support the plant growth. In experiment 2, plants were grown in soils containing 0-200 ppm Cd for 30 days. In both experiments, plant growth was inhibited in all Cd treated groups. No difference in plant growth was observed between 100-200 ppm Cd treated groups. In experiment 3, plants were treated with 0-200 ppm Cd in the soils, and grown for 60 days. Results indicate that plant growth was reduced in all Cd-treated groups, however, the 60-day growth period produced higher plant biomass compared to the 30-day growth cycle. In order to observe a time related growth pattern, in experiment 4, plants were grown under color corrected lights and harvested on days 14,21,28, and 35 of the experiment. Results indicate that plant growth was better in the laboratory conditions than in the greenhouse. Experiments show that the tolerance limit of Ipomoea to soil Cd lies between 200-250 ppm, plant growth response is similar between 100-200 ppm Cd, and a longer growth period produces higher biomass that may enhance Cd hyperaccumulation by plants.

EFFECTS OF LEAD AND CADMIUM ON SOIL PHOSPHATASE ACTIVITY

Umeko Griffin (*), Ashley Swanier, Courtney Young, Oscar Hundley, Afrachanna Butler, Maria Begonia, and Gregorio Begonia, Jackson State University, Jackson, MS 39217

Heavy metals, such as lead (Pb) and cadmium (Cd), have been found to exert an adverse effect on some soil biological activities such as respiration and biomass. One quick way to obtain information on the biological activity of soil microorganisms is by measuring phosphatase activity. The primary objective of this study was to investigate the effects of lead and cadmium on the phosphatase activity of soil amended with such metals. In this study, soils that were previously amended with various metal concentrations and planted with wheat for six weeks were used for the assay of phosphatase after they have been cleaned of debris, air-dried, pulverized and sieved to the desired particle size. Results showed that phosphatase activity exhibited different sensitivity to the heavy metals (cadmium and lead) and chelates (EGTA and EDTA) that were amended to the soil. Phosphatase activity decreased with increasing levels of soil Pb treatments compared to controls. Across 3 Pb treatments (e.g., 500, 1,000, and 2,000mg Pb/ kg dry soil), phosphatase activity was elevated at 500 and 1,000 treatments (but not at 2,000) with the addition of 5.0 mmol EDTA/kg dry soil before planting. Across 3 Cd treatments (e.g., 500, 1,000 and 2,000 mg Cd/kg dry soil), phosphatase activity increased at 500 but decreased at both 1,000 and 2,000 Cd treatments. The chelate EDTA generally increased phosphatase activity at 500 and 1,000 Cd treatments but not at 2,000 treatment. The results indicate that the phosphatase activity depends on the lead and cadmium contents of the soil.

CHEMICALLY-ENHANCED PHYTOEXTRACTION OF CADMIUM-CONTAMINATED SOILS USING WHEAT (TRITICUM AESTIVUM L.)

Courtney Young (*), Ashley Davis, Oscar Hundley, Umeko Griffin, Afrachanna Butler, Maria Begonia, and Gregorio Begonia, Jackson State University, Jackson, MS 39217

There is an increasing interest in phytoextraction as an alternative technology to clean up cadmium contaminated soils. In phytoextraction, an efficient plant species must be able to tolerate toxic metal levels, and accumulate substantial amounts of the metal into the shoots. Phytoextraction also depends upon the availability of the metal for absorption by the roots. This study was conducted to determine the optimum concentration of[ethylenebis (oxyethylenenitrilo)] tetraacetic acid (EGTA) on shoot accumulation of Cd by wheat grown on a Cd-contaminated soil. Wheat (Triticum aestivum L.cv. TAMIO9) seeds were sown in each 150 mL plastic tube containing a growth medium composed of sieved soil and peat (2:1; v:v). Desired Cd (0, 500, 1000 mg Cd/kg) and EGTA (0, 1.0, 2.5, 5.0 mmol/kg) treatments were imposed before planting. Treatments were arranged in a 3 Cd x 4 EGTA factorial in a Completely Randomized Design with 4 replications. Results showed that wheat plants were relatively tolerant to Cd x EGTA combinations as exhibited by non-significant differences in their chlorophyll contents and dry biomass. Wheat plants grown in soils amended with a combination of 1000mg Cd/kg x 5.0 mmol EGTA/kg had the highest root and shoot Cd accumulations.

THE ECONOMIC BENEFITS OF COLLARD YIELDS ON FARM INCOME USING PLANTING DENSITY FACTOR

Ahmed H. Al-Humadi (*), Liang C. Huam, Giish K. Panicker, and Cedric A. Sims, Alcom State University, Alcom State, MS 39096

Collard is a member of the Brassica family (Cruciferae). They are rich in protein, minerals, and vitamins A and C. A study was conducted in spring 2000, in the southwest Mississippi on a Collard cultivar namely Brassica oleracea var. vates to determine the cost benefits of production in relation to planting density. The cultivar was raised in two plots often rows each at low density planting (LDP), 0.9 14 mx 0.228 m and high density planting (HDP), 0.9 14 m x 0.152 m on Memphis Silt Loam Soil. Irrigation, fertilization, insecticides and herbicides were applied uniformly on both plots. Total costs of production were calculated and compared with the average costs of commercial production. Field results indicated that total yield was significantly higher in low density planting (16,729 kg/ha) than high density planting (15,388 kg/ha). Consequently, the economic benefits of low density planting were greater than high density planting.

CHELATOR INDUCED PHYTOACCUMULATION OF CADMIUM IN BRASSICA JUNCEA GROWN IN CADMIUM CONTAMINATED SOIL

M.S. Zaman (1 *), C.P. Jennings', and K.L. Shumaker (2), Alcorn (1) State University, Alcom State, MS 39069, and (2) Jackson State University, Jackson, MS 39217

Environmental stress of soil cadmium (Cd) pollution on plant and chelator induced hyperaccumulation of Cd in plant tissue were studied in Brassica juncea (Indian Mustard) plants, grown in soil containing 50 ppm of Cd and various concentration of ethylene diamine tetraacetic acid (EDTA). Data were analyzed for plant biomass, Grade of Growth Inhibition (GGI), and Cd uptake by Cd treated plants. Root, shoot and total plant biomass was significantly reduced in plants treated with Cd and/or EDTA compared to Control group. Root, shoot and total plant GGI was also significant in all Cd and/or EDTA treated groups compared to Control group. Tissue Cd concentrations in root, shoot and total plant were significantly higher in Cd or Cd + EDTA treated groups. Without the application of EDTA, the root Cd accumulation was about 283% higher and the shoot Cd accumulation was about 167% higher than the 50 ppm soil Cd concentration, With the application of EDTA, Cd accumulations were found to be enhanced up to 458% and 400% abo ve the soil Cd concentration in the root and shoot tissues respectively. Overall, data indicated that B. juncea is a Cd hyperaccumulator and can be used for phytoremediation of Cd contaminated soil. And application of EDTA to the soil will amplify the Cd hyperaccumulation and enhance the phytoremediation process.

THURSDAY AFTERNOON

Lamar I

1:45 MODIFICATION OF INPUTS TO GROW ORGANIC BERMUDAGRASS HAY

D.J. Lang (*), M. Broome, and R.L. Elinore, Mississippi State University, Starkville, MS 39762

Alternatives to fertilizer for hay production include utilization of animal wastes and incorporation of persistent legumes. Objectives were to compare the first year response of 'Sumrall' bermudagrass Cynodon dactylon L. to combinations of poultry litter pellets (PP), legumes, conventional fertilizer (CF), and cultural weed control practices on yield and species composition. Bermudagrass was burned with fire in late February, 2001. Poultry Pellets (6-2-4) were applied at 65 lbs N/Acre (1100 lbs/acre) 2x (May and August) or 3x (May, July, August). Commercial fertilizer (15-5-10) was also applied 2x and 3x as above. 'Bigbee' Berseem clover (Trifloium alexandrium) was planted along with 'Marshall' Ryegrass (Lolium multiflorum L.) in October for winter weed control in no-herbicide plots. Species composition was determined visually at each harvest and yield was obtained by clipping. Bermudagrass yield fertilized with PP3x was low (4384 lbs/A) compared with PP 2x + CF1x (6796 lbs/A). Nitrogen release from PP was in itially inadequate to provide vigorous bermudagrass growth. Transition from conventional inorganic fertilizer to organic fertilizer will require both higher equivalent N rates and additional time for organic bound N in PP to be mineralized. The unique aspect of this study is that we are using biological and ecological processes to control weeds and provide nutrients for economically viable organic bermudagrass hay production.

2:00 EFFECT OF C:N RATIO AND SOIL DEPTH ON THE RATE OF DECOMPOSITION OF BRASSICA OLEACEAE RESIDUES

Girish K. Panicker (*), Ahmad H. Alhumadi, and Cedric A. Sims, Alcom State University, Alcom State, MS 39096

Residue management has been established as a valuable technology for reducing soil erosion from agricultural lands. Data on the rate of residue decomposition is an integral part of erosion prediction models. As a part of the research being conducted on horticultural crops for erosion prediction models, fresh residues of cabbage (Brassica oleraceae L. var. capitata) were placed in fiberglass mesh bags either at the surface or 15 cm deep in a Memphis Silt Loam soil (Typic Hapludalf, silty, mixed, thennic) and were allowed to undergo decomposition for a period of six months. Decomposing samples were collected from the field every 10 days and analyzed for organic C and N. Subsurfaced residues with low C:N ratios decomposed faster than the subsur-faced root residues with high C:N ratios. The surfaced root and shoot residues decomposed slower than the subsurfaced residues. The decomposition rates of both

subsurfaced shoot and root were negatively correlated with the low C:N ratios. The results in general showed tha t the decomposition of crop residues was a function of C:N ratio and the placement in soil.

2:15 MAXIMIZING SWEET POTATO (IPOMOEA BATATAS) YIELD IN THE MISSISSIPPI DELTA THROUGH REMOTE SENSING GLOBAL POSITION SYSTEMS (GPS) AND GROUND TRUTHING

Abdullah F.H. Muhammad (*), Kwekor Donkor, and Kendrea Shelvy, Alcom State University, Alcom State, MS 39096

A 2.72 acre plot of the virus tested (G1/G2) sweet potato cultivar 'Beauregard' were divided into 21 GPS studied over a two year period (2001 and 2002) at the Alcom State University Extension/Reserach Farm in Mound Bayou, MS. The objectives were to use remote sensing, GPS, ground truthing via grid sampling and statistical analysis to: 1. Identify soil and plant properties that enhance or limited yield and quality of sweet potatoes. 2. Identify problematic areas in field associated with soil moisture, texture, pH etc. 3. Developed corrective techniques based on results obtained that may increase yield and improve quality in problematic areas. Results indicate tremendous variability among the twenty one GPS points in soil moisture, texture, pH, nutrition status, canopy temperature and yield. Some specific recommendations are deep plowing, liming and rehipping raised beds.

2:30 RESPONSE OF VIBRIO VULNIFICUS AND V PARAHAEMOLYTICUS 03:K6 TO HOT WATERICOLD SHOCK PASTEURIZATION PROCESS

Linda S. Andrews (*) and Susan DeBlanc, Mississippi State University, Biloxi, MS 39531

Vibrio vulnificus and V. parahaemolyticus are natural inhabitants of estuarine environments world wide. Pathogenic strains of these bacteria are often transmitted to humans through consumption of raw oysters which flourish in these same estuaries. Previous studies by these authors reported the effective use of hot water pasteurization followed by cold shock to eliminate, from raw oysters, naturally and artificially incurred environmental strains of V. vulnificus and V. parahaemolyticus common to the Gulf of Mexico. This study was continued with the use of the pasteurization method to reduce pathogenic strains of Vibrio, known to be more process resistant. Oysters were artificially contaminated with pathogenic strains of V. vulnificus and V parahaemolyticus at a concentration of 106 cfu/g oyster meat. Contaminated oysters were pasteurized at 52[degrees]C for up to 22 minutes. Samples of processed oysters were enumerated for Vibrios at 2 min intervals after their internal temperature reached 50[degrees]C The V. vulnificus and V. parahaemolyticus O3:K6 proved to be more process resistant than nonpathogenic environmental strains found in Gulf of Mexico waters. A total process time of at least 22 minutes, in 52[degrees]C water, was recommended as a valid process parameter to eliminate potential pathogenic Vibrios from shell stock oysters.

3:00 Divisional Business Meeting and Awards