AGRICULTURE AND PLANT SCIENCE.Chair: James O. Garner, Mississippi State University Mississippi State University, at Mississippi State, near Starkville; land-grant and state supported; coeducational; chartered 1878 as an agricultural and mechanical college, opened 1880. From 1932 to 1958 it was known as Mississippi State College. Vicechair: Franklin O. Chukwuma, Alcorn State University Alcorn State University, located near Lorman, Mississippi, United States, is a public land grant university. It was founded in 1871 as the nation's first state-supported higher education institution for blacks. THURSDAY MORNING Deer Isle 9:05 Introduction James O. Garner, Jr., Mississippi State University, Mississippi State, MS 39762 9:15 RESPONSE OF LEAF AND CANOPY SPECTRAL REFLECTANCE TO DROUGHT AND FUNGAL STRESS IN SOYBEAN Judge Brown [*], Raj Bahadur Ba`ha´dur n. 1. A title of respect or honor given to European officers in East Indian state papers, and colloquially, and among the natives, to distinguished officials and other important personages. , and Abdullah Faruque, Mississippi Valley State University Mississippi Valley State University is a historically black university located in Itta Bena, Mississippi. The university is commonly referred to as MVSU or simply "The Valley." MVSU is a member school of the Thurgood Marshall Scholarship Fund. , Itta Bena, MS 38941 Plants of two soybean varieties, traditional DP3588 and high tech. 92B71-Roundup ready, were grown in greenhouse and in the field at Stoneville, MS and East Lansing, MI for primarily drought stress studies. The objective of this study funded by National Aeronautics Space Administration (NASA NASA: see National Aeronautics and Space Administration. NASA in full National Aeronautics and Space Administration Independent U.S. ) at Stennis Space Center was to record the spectral reflectance differences of leaf and canopy stress caused by drought and white mold disease. Plant physiological measurements of leaf water content, leaf water potential and other growth and development data were correlated with the percentage of spectral reflectance of leaf and canopy. Neural network and other statistical techniques were used to analyze plant and soil water relations and the reflectance data acquired with the spectroradiometer. Students were trained in conducting experiments, collecting and analyzing the data. Results of three levels of fungal infection and two levels of drought stress in leaf and canopy are presented. Incorporating this technology in s atellites, economic crops could be monitored world wide for signs of damaging drought stress, which could lead to more reliable predictions of crop yields and remove weather-driven volatility from grain commodity markets. Further research for refining the techniques of predicting by remote sensing crop-damaging effects of drought and possibly irrigating can be economically beneficial. 9:30 LEAD ACCUMULATION OVERTIME IN TWO WEED SPECIES, SESBANIA EXALTATA (RAF.) AND IPOMOEA Ipomoea widespread genus of poisonous vines of the family Convolvulaceae; may contain various toxins including the indole alkaloid lysergic acid, furanoterpenes, indolizidine alkaloids (swainsonine). Includes I. asarifolia (salsa), I. LACUNOSA L. IN HYDROPONIC CULTURE Susmita Ghosh [*], Amelya Hardaway, Jennifer N. Ntoni, Aladin Siddig, and Charles Rhyne, Jackson State University Jackson State University, often abridged as Jackson State or by its initials JSU is a historically black university located in Jackson, Mississippi founded in 1877. , Jackson, MS 39217 The time of exposure to can he an important factor affecting the accumulation in different plant parts. A modified hydroponic growing system was used to suspend two weed species, Sesbania exaltata (Raf.) and Ipomoea lacunosa L. in aqueous solutions of either Hoagland's nutrient solution or 500 mg/L of Pb[([NO.sub.3]).sub.2] in the laboratory. Plants were harvested and separated into shoots and roots at the end of 7, 14, 21, 29, and 35 days of growing. Heights and dry weights were recorded after each harvesting. In case of Sesbania exaltata (Raf.), Pb accumulation in shoots was 1398 (.1%) and 1399 (.1%) mg/kg with root accumulations of 18401 (1.8%) and 7231 (.7%) mg/kg at the end of 7 and 14 days respectively. In case of Ipomoea lacunasa L., shoot Pb accumulations after 7 and 14 days were 1635 (.2%) and 1778 (.2%) mg/kg respectively. Accumulation by roots of the plants was deduced at the end of 14 days (5445 mg/kg) compared to the accumulation (9067 kg) at the end of 7 days. Translocation translocation /trans·lo·ca·tion/ (trans?lo-ka´shun) the attachment of a fragment of one chromosome to a nonhomologous chromosome. Abbreviated t. of Pb to the shoots showed an in with time in both species. Further data will be provided at the time of presentation. 9:45 A COMPARATIVE ANALYSIS OF WEEDING COST UNDER DIFFERENT MULCHING PRACTICES IN TOMATO CULTIVATION Kat M. Lee [*], Liang C. Huam, and Akpan Idung, Alcorn State University, Alcorn State, MS 39096 Black plastic and sweet potato intercrop in·ter·crop v. in·ter·cropped, in·ter·crop·ping, in·ter·crops v.intr. To grow more than one crop in the same field, especially in alternating rows or sections. v.tr. plots were compared to unmulch plots in a study to determine weeding cost in tomato cultivation. Weed numbers and weeding time spent under each medium were recorded. Weed control was most effective under plastic mulching, followed distantly behind by intercrop and unmulch. Weed numbers and hand weeding time were related to ground surface cover and physical crowding, and shading from competing growth of mulching medium and main crop. Weeding cost by manual labor was almost the same under intercrop and unmulch, and lowest under plastic medium. Analysis of enterprise budgets indicate labor cost constituted about one-half to three-fourth of total variable cost whereas hand weeding labor cost constituted about one-thirtieth of that under plastic to almost one-half under intercrop mulching and unmulch. Analysis of partial budgets indicated a positive net change from switching intercrop mulching and unmulch to plastic mulching medium while a negative net change was evident if hand labor weeding cost was excluded in the budgets. Under a small farm situation, the difference in net income change is primarily due to reductions in weeding cost since labor can be provided by the operator. 10:00 ROOTING OF PECAN CUTTINGS BY GIRDLING AND BANDING Frank B. Matta, Mississippi State University, Mississippi State, MS 39762 Nine-year old bearing grafted pecan trees were used in this study. Varieties propagated were 'Choctaw,' 'Kiowa,' 'Cheyenne,' 'Shoshoni,' and 'Pawnee.' Main limbs producing one-year old wood were girdled. Current seasons shoots originating from one-year old wood on girdled limbs were banded at the base with one-half inch wide electrical tape. Cuttings were harvested five weeks after banding, immersed in Captan captan group of organic sulfur compounds used as fungicides, including topical treatment of dermatophytosis. Poisoning of birds causes loss of egg production, anorexia and slow growth. [R], placed in propagation flats filled with rooting media, and placed in a greenhouse under intermittent mist for rooting. Rooting was cultivar cultivar Any variety of a plant, originating through cloning or hybridization (see clone, hybrid), known only in cultivation. In asexually propagated plants, a cultivar is a clone considered valuable enough to have its own name; in sexually propagated plants, a dependent with 'Pawnee' having a greater percentage rooting regardless of treatment. Girdling and banding increased rooting of 'Cheyenne.' 'Choctaw' responded the least to girdling and banding and banding alone. 10:15 PHYTOEXTRACTION OF CADMIUM FROM SOLUTION BY CYMBOPOGON FLEXUOSUS L., A PRELIMINARY STUDY Susmita Ghosh [*], Amelya Hardaway, Jennifer N. Ntoni, and Charles Rhyne, Jackson State University. Jackson, MS 39217 Phytoextraction, or removing certain metals or organic compounds from contaminated soil or water and concentrating them in the harvestable parts is a natural process carried out by few plants. Our research objective is based on surveying and identifying wide-ranging plant species as potential hyperaccumulators. A modified hydroponic growing system was used to suspend plants in aqueous solutions of either Hoagland's nutrient solution or varying concentrations of Cd([NO.sub.3][).sub.2]. Plants were exposed to Cd concentrations of 50, 100 and 200 mg/L. After four weeks of exposure, plants were harvested and separated into shoots and roots to analyze the accumulations of Cd. Accumulation of Cd in shoots of 50 mg/L test concentration was 3373 (.3%), mg/kg the highest among shoots and, 16289 (1.6%) mg/kg, of Cd in roots of 200 mg/L test concentration was the highest among roots. Dry weights of the plants in different test concentrations were also recorded. The high Cd accumulation by Cymbopogon flexuosus L. sugges ts that this plant may be used to clean up Cd-contaminated sites using the phytoextraction process. 10:30 Break 10:45 THE RELATIONSHIP BETWEEN FATTY ACID CONTENT AND PECAN COLD HARDINESS Jeb Cade [*] and Frank B. Matta, Mississippi State University, Mississippi State, MS 39762 Seasonal fatty acid changes in total lipids of 'Jackson' and 'Owens' pecan from September to March were determined. The predominant fatty acids were linolenic (18:3), linolenic (18:2), oleic (18:1), stearic (18:0), and palmitic (16:0). In both cultivars, total saturated fatty acid saturated fatty acid n. A fatty acid, such as stearic acid, whose carbon chain contains no unsaturated linkages between carbon atoms and hence cannot incorporate any more hydrogen atoms. content was negatively correlated with cold hardiness and negatively correlated with total unsaturated fatty acid unsaturated fatty acid n. A fatty acid, such as oleic acid, whose carbon chain possesses one or more double or triple bonds and hence can incorporate additional hydrogen atoms. content. Total unsaturated fatty acid content was positively correlated with cold hardiness. In 'Owens' 16:0 was significantly correlated with cold hardiness and total saturated fatty acid content. 11:00 AIR TEMPERATURE INFLUENCES THE EFFECT OF GROWTH REGULATORS ON COLD HARDINESS OF BLUEBERRY blueberry, plant of the large genus Vaccinium, widely distributed shrubs (occasionally small trees) of the family Ericaceae (heath family), usually found on acid soil. They are often confused with the related huckleberry. Girish K. Panicker [*], Frank B. Matta, and Patrick D. Gerard, Mississippi State University, MS 39762 A two-year study was conducted on rabbiteye var 'Tifblue' flower flushes to determine the effect of three concentrations of abscisic acid (ABA) and paclobutrazol on cold hardiness of floral parts. Two types of flower flus4es were identified in 'Tifblue.' Differential thermal analysis Differential thermal analysis (or DTA) is a thermoanalytic technique, similar to differential scanning calorimetry. In this technique, the heat flow to the sample and reference remains constant, as opposed to temperature. (DTA), electrolyte leakage (EL), tetrazolium stain test and oxidative browning test were conducted on floral parts to determine the critical freezing temperatures. Floral parts frozen to 40[degrees]C produced only one exotherm confirming that rabbiteye floral parts do not supercool su·per·cool v. su·per·cooled, su·per·cool·ing, su·per·cools v.tr. To cool (a liquid) below a transition temperature without the transition occurring, especially to cool below the freezing point without . Both growth regulators induced hardiness in all floral parts at second flush, and induced hardiness only in certain floral parts at first flush. Floral parts in April were more prone to freezing injury than floral parts in March. Ovaries were the hardiest followed by calyx calyx (kā`lĭks): see sepal. , stamens, style and corolla. Air temperature had profound influence on cold hardiness as determined by DTA and the viability tests. 11:15 ALLEVIATION OF CHILLING INJURY IN SWEET POTATO (IPOMOEA BATATA ba·ta·ta n. A type of sweet potato having somewhat dry, bland, yellowish to white flesh, used as a staple food in many tropical countries. Also called boniato, camote. L.) BY GLK-8903 Ibrahim Makhadmeh [*] and James O. Gamer, Jr., Mississippi State University, Mississippi State, MS 39762 Twelve-day old rooted stem cuttings of 'Travis' sweet potato plants were foliar foliar pertaining to or having the quality of leaves. sprayed with 1% GLK-8903. Twenty four hours after treatment the plants were chilled (5[degrees]C day/night, 12 hr. of fight). Non-chilled plants were kept at 25[degrees]c day/night in another growth chamber. After 24 hrs leaves of the untreated control were injured, as characterized by leaf wilting, whereas leaves of the GLK-8903 treated plants retained turged. The GLK-8903 protection mechanism was assessed by examine several physiological response. No differences in diffusive dif·fu·sive adj. Characterized by diffusion. dif·fu  sive·ly adv.dif·fu resistance, transpiration transpiration, in botany, the loss of water by evaporation in terrestrial plants. Some evaporation occurs directly through the exposed walls of surface cells, but the greatest amount takes place through the stomates, or intercellular spaces (see leaf). rate and chlorophyll content were detected between treated and non-treated plants. The decline in relative water content (RWQ and chlorophyll fluorescence ratio Fv/Frn caused by chilling exposure to 5[degrees]C were minimized by the application of GLK-8903. RWC of treated plants increased from 78% to 90% under chilling. Treated plants had 0.215 Fv/Fm compared with non-treated 0.165. Electrolyte leakage, an indication of membrane in jury was reduced from 20.9 to 9.7 with the GLK-8903 treatment. The activity of peroxidase was increased by GLK-8903 application. Malondialdehye (MDA (1) (Monochrome Display Adapter) The first IBM PC monochrome video display standard for text. Due to its lack of graphics, MDA cards were often replaced with Hercules cards, which provided both text and graphics. See PC display modes and Hercules Graphics. ), a product of lipid peroxidation was increased in untreated plants under chilling exposure. Under non-chilling conditions, there were no differences between treated and non-treated plants. 11:30 PHYSIOLOGICAL EVALUATION OF CHILLING TOLERANCE Ehiorobo Izekor [*] and James O. Garner, Jr., Mississippi State University, Mississippi State, MS 39762 Four chilling tolerant sweet potato genotypes were physiologically evaluated for similarities in traits relating to tolerance to chilling injury. Chilling decreased transpiration rate (TR) and increased diffusive resistance among the genotypes tested. Electrolyte leakage (EL) was increased by 61% and peroxidase activity was also increased by 75% following 5[degrees]C chilling for 24 hours Adv. 1. for 24 hours - without stopping; "she worked around the clock" around the clock, round the clock . Genotype effect on chilling temperature was supported by chilling-genotype interaction for chlorophyll fluorescence yield. Genotype 108MS3 had 0.38 chlorophyll fluorescence ratio (Fv/Fm) compared to genotype 105MS1 with 0.16 Fv/Fm when chilled. There was no difference among genotype in percent fatty acid composition before and after chilling among the chilling tolerance genotypes tested. However, more than 70% of the fatty acid composition of the glycolipid Glycolipid One of a class of compounds having solubility properties of a lipid and containing one or more molecules of a covalently attached sugar. fraction of the total lipid was linoleic (18:2) and linolenic (18:3). Genotype effect was also recorded for percent leaf shrinkage of the anatomy. The largest shrinkage s due to water loss among the genotypes were observed in the palisade layer (40%) and epidermal layer (49%). Total leaf shrinkage, stomata sto·ma·ta n. A plural of stoma. density, diffusive resistance and transpiration rate may have interacted with leaf water content and specific leaf weight with respect to water loss of the leaf under chilling condition. 11:45 FIELD EVALUATION OF ECHINACEA echinacea (ĕk'ənā`shēə), popular herbal remedy, or botanical, believed to benefit the immune system. It is used especially to alleviate common colds and the flu, but several controlled studies using it as a cold medicine have SPECIES Patrick E. Igbokwe [*], Muhammad Rizvi, Liang C. Huam, Magid Dagher, and LaShunda L. Anderson, Alcorn State University, Alcorn State, MS 39096 A field study was conducted in the summer of 1999 to determine the adaptation, growth potential and mineral composition of Echinacea angustifolia, E. dallida, and E. dufpurea. The study was conducted on a Memphis silt loam soil at Alcorn Experiment Station. A randomized ran·dom·ize tr.v. ran·dom·ized, ran·dom·iz·ing, ran·dom·iz·es To make random in arrangement, especially in order to control the variables in an experiment. complete block experiment design, with four replications of each species was used. Each species was planted into beds 6.1 m long and 1.5 m wide at a within-row spacing of 0.3 m and a between-row spacing of 0.3 m. Fertilizer (N-P-K) application was based on recommendation after sod test. Other production practices were uniformly applied to all plots. Plant survival was greatest for E. pufpurea and lowest for E. angustifolia. Ganopy width, canopy height, flower formation and growth were also greatest for E. purpurea and lowest for E. angustifolia. THURSDAY AFTERNOON Deer Isle 1:00 Divisional Poster Session PHYTOREMEDIATION phy·to·re·me·di·a·tion n. The use of plants and trees to remove or neutralize contaminants, as in polluted soil or water. phytoremediation See under bioremediation. OF TRINITROTOLUENE trinitrotoluene or TNT (trī'nī'trōtŏl`y  ēn), CH3C6H2(NO2)3 (TNT TNT: see trinitrotoluene. TNT in full trinitrotoluene Pale yellow, solid organic compound made by adding nitrate (−NO2) groups to toluene. ) USING SPINACH (SPINACIA SPINOSA) FILTRATE filtrate /fil·trate/ (fil´trat) a liquid or gas that has passed through a filter. fil·trate v. To put or go through a filter. n. Lovell Agwaramgbo [1], Steven L. Larson [2], Willie W. Craft, Jr. [1][*], and Charlie A. Cheney [1], (1.) Tougaloo College, Tougaloo, MS 39174 and (2.) U.S. Army Corps of Engineers, Waterways Experiment, Vicksburg, MS 39180-6199 Trinitrotoluene (TNT) and its degradation products pose a treat to our environment due to their toxic and mutagenic mutagenic inducing genetic mutation. nature. This explosive is known to contaminate surface and groundwater, especially near munition sites, that may later be used for irrigation irrigation, in agriculture, artificial watering of the land. Although used chiefly in regions with annual rainfall of less than 20 in. (51 cm), it is also used in wetter areas to grow certain crops, e.g., rice. of food crops. The spinach green (Spinacia spinosa) was made into a puree, filtered to remove any insoluble solid particles, and added to a 100 ppm solution of TNT. High-performance liquid chromatography was then utilized to test the degradation of TNT using the spinach. Analysis showed that over a period of 32 hours the spinach significantly reduced the concentration of TNT even after the removal of all insoluble solid particles. This result suggests that the degradation of TNT by the spinach was enzymatic rather than adsorption. Acknowledgements: (a) This project was funded by the U.S. Army Corps of Engineers (b) We thank the WES Environmental Chemistry Branch Management for providing us with the research facility, supplies, and office space. THE SCRAMBLE FOR PLANT MATERIALS BY SOLVENTS: IMPLICATIONS ON TNT REMEDIATION Lovell Agwaramgbo [1][*], Steven L. Larson [2], Chris Foote [2], Lynn Escalon [2], and Waleska Perez [3], (1.) Tougalco College, Tougaloo MS 39174; (2.) U.S. Army Corps of Engineers, Waterways Experiment, Vicksburg, MS 39180-6199; and (3.) University of Puerto Rico Founded in 1903, the University of Puerto Rico (Universidad de Puerto Rico in Spanish, UPR) is the oldest and largest university system in Puerto Rico. Though Puerto Rico is not a U.S. , Mayaguez, Puerto Rico Phytoremediation research has concentrated on the aqueous matrix since the technology will be used for water, sludge, or soil treatment. No study has been conducted to examine the partitioning of the plant materials between organic and aqueous matrices. This study examines the reaction of TNT with the organic and aqueous extracts and the un-extractable marcs of mustard green and spinach using 100% hexane hexane /hex·ane/ (hek´san) a saturated hydrogen obtained by distillation from petroleum. hex·ane n. , 100% acetone, and 50/50 hexane-acetone as solvents, respectively. A fresh and un-extracted spinach juice was filtered and treated with TNT as a control experiment. The marcs degraded TNT at varying rates but re moved TNT faster than the aqueous layer after organic solvent extraction. The mustard green marc from the hexaneacetone extraction removed TNT faster than the corresponding spinach marc. The marcs from the 100% hexane extraction removed TNT equally but faster than the other reactions. The spinach aqueous layer from the hexane. acetone extraction removed TNT faster than that of the corresponding musta rd green. The fresh but filtered spinach juice removed TNT faster than all the marcs and extracts except the pure and fresh marc. These results suggest that: (a) there may be more than one plant component and reaction involved in phyto removal, degradation, or transformation of TNT; (b) hexane does not extract all the plant components that degrade TNT (c) removal of TNT is not due to adsorption by the plant material. Support for this project was provided by the United States Corp of Engineers & MSEIP MSEIP Minority Science and Engineering Improvement Program . PHYTOREMEDIATION OF TNT BY SEVEN TERRESTRIAL PLANTS Lovell Agwaramgbo [1][*], Steven L. Larson [2], Victor Medina [3], and Waleska Perez [4], (1.) Tougaloo College, Tougaloo, MS 391742; (2.) U.S. Army Corps of Engineers, Waterways Experiment, Vicksburg, MS 39180-6199; (3.) University of Puerto Rico, Mayaguez, Puerto Rico; and (4.) Washington State University Washington State University, at Pullman; land-grant and state supported; chartered 1890, opened 1892 as an agriculture college. From 1905 to 1959 it was the State College of Washington. , Tri Cities, Richland WA 99352 Phytoremediation, a nascent technology is the use of plants to remove contaminants from various media. This technology is economically attractive and environmentally friendly and acceptable. Much research has focussed on munitions mu·ni·tion n. War materiel, especially weapons and ammunition. Often used in the plural. tr.v. mu·ni·tioned, mu·ni·tion·ing, mu·ni·tions To supply with munitions. remediation using microbes and aquatic plants. This study investigates the use of terrestrial plants as a viable alternative to solving the enormous munitions pollution. Terrestrial plants are bulkier and more abundant. The seven plants were chosen at random; various TNT solutions were treated with each plant, respectively. It was observed that in some cases, there were no detectable levels of TNT after four hours. Some of the plants were selected for reaction with RDX. The results of these investigations will be discussed and shared. Support for this project was provided by the United States Corps of Engineers & MSEIP. ADSORPTION AND DESORPTION Desorption A process in which atomic and molecular species residing on the surface of a solid leave the surface and enter the surrounding gas or vacuum. OF METOLACHLOR IN A LOESSIAL SOIL F.O. Chukwuma [*] and A.B. Johnson, Alcorn State University, Alcorn State, MS 39096 The key step in designing management practices that will reduce surface and groundwater pollution is understanding the sorption sorption /sorp·tion/ (sorp´shun) the process or state of being sorbed; absorption or adsorption. sorp·tion n. Adsorption or absorption. and desorption of herbicides in soils: Therefore, the objective ofthis study was to determine the influence of varied equilibrium time on the overall sorption and desorption of metolachlor by a Loring silt loam soil (Fine-silty, mixed, thermic thermic /ther·mic/ (ther´mik) pertaining to heat. thermic pertaining to heat. Typic Fragiudalfs). Soil samples were collected from Ap (0-15 cm) horizon, air dried, sieved ([less than] 2 mm) and selected physico-chemical properties determined. Sorption isotherms were obtained by placing 3 g of soil in 25 ml corex glass centrifuge tubes with Teflon-lined caps. Fifteen ml of metolachlor of different concentrations (0, 2, 4, 10, 16, 20 mg L [-1] were added in triplicated to each tube for five equilibrium times (1,24,48, 72 and 96 h). After each equilibrium time, the suspensions were centrifuged and 7 ml from each sample was filtered and solution concentration analyzed for metolachlor using HPLC HPLC high-performance liquid chromatography. HPLC high performance liquid chromatography. HPLC High-performance liquid chromatography Lab instrumentation A highly sensitive analytic method in which analytes are placed . Desorption was measured afte r sorption using the highest concentration for each equilibrium time. Seven ml of background solution (0.01 M [CaCl.sub.2]) was added to each sample, vertexed and was shaken accordingly. This procedure was repeated 5 times and the supenatant analyzed as above for metolachlor. Adsorption-desorption isotherms were then fit to the logarithmic form of the Freundlich equation. PHYTOEXTRACTION OF LEAD FROM CONTAMINATED SOILS: ROLE OF A SYNTHETIC CHELATE chelate Any of a class of coordination or complex compounds consisting of a central atom of a metal (usually a transition element) attached to a large molecule (ligand). G. Miller [*], M.F.T. Begonia begonia (bĭgōn`yə), any plant of the large genus Begonia and common name for the family Begoniaceae, mostly succulent perennial herbs of the American tropics cultivated elsewhere as bedding or pot plants and easily propagated by , G.B. Begonia, C. Burks [*], J. Owens, and M. Johnson, Jackson State University, Jackson, MS 39217 Previous hydroponic studies indicated that coffee-weed or hemp Sesbania (Sesbania exaltata Raf.) can accumulate substantial amounts of lead (Pb) in its shoots. To further evaluate the effectiveness of S. exaltata as a phyto-extraction species, a study was conducted to determine whether a synthetic chelate, ethylenediaminetetraacetic acid (EDTA EDTA: see chelating agents. ), can enhance the shoot uptake of Pb from a contaminated soil. Seeds of hemp Sesbania were planted in 1.8 L plastic pots containing planting mix:top soil (2:1, v:v) amended with aqueous solutions of Pb and EDTA. Experimental units were arranged in a 4 Pb x 5 EDTA factorial in RCB with 5 replications. Results showed that shoot and root dry biomass of hemp Sesbania were not significantly affected by the various Pb/EDTA treatments. Pb uptake in the shoot increased with increasing levels of soil-applied Pb but was not enhanced by EDTA. Pb accumulation in the roots was only increased at the two highest levels of soil-applied Pb in combination with 5 mM EDTA. The concentrati ons of Pb remaining in the soil after harvest were directly proportional to the levels of soil applied Pb but were not affected by chelate amendments. EVALUATION OF DIFFERENT TRELLIS SYSTEMS FOR CHINESE MELON (MOMORDICA CHARANTIA L Momordica charantia L., n See bitter melon. .) PRODUCTION O.P. Vadhwa [1][*], C.R. Reddy [1] , and James Spiers [2], (1.) Alcom State University, Alcorn State, MS 39096 and (2.) USDA USDA, n.pr See United States Department of Agriculture. Small Fruit Research Station, Poplarville, MS 39470 Chinese melon (Momordica charantia L.) yield as influenced by four trellis systems was evaluated. Chinese melon seeds of cultivar Durga an Indian variety were used for this study and planted on June 2, 1999. Chinese melon plants grown without trellis (control) were the least productive. Maximum yield was obtained with V-shaped trellis system followed by vertical and semi-vertical trellis systems. Harvesting was more convenient with all trellis systems as compared to control where the plants were allowed to trail and spread on the ground. First harvest date was July 23, 1999 (50 days after transplanting) and final harvest date was October 25, 1999 (144 days after transplanting). RESPONSES OF INDIAN MUSTARD TO SOIL CADMIUM AND LEAD POLLUTION K. Shumaker, M.S. Zaman [*], V. Boyd, and Alice M. Powell, Alcorn State University, Alcorn State, MS 39096 Cadmium (Cd) and lead (Pb) are ubiquitous pollutants in the biosphere. Studies in our laboratory indicate that Brassica brassica Any plant of the large genus Brassica, in the mustard family, containing about 40 Old World species and including the cabbages, mustards, and rapes. B. oleracea has many edible varieties, such as broccoli, Brussels sprouts, cabbage, cauliflower, kale, and kohlrabi. juncea (Indian mustard) plants can tolerate high concentrations of Cd and Pb in soil. In this study, we evaluated the comparative biotoxic effects of Cd and Pb on B. juncea. Plants were grown on Memphis silt loam soil, polluted with various concentrations of Cd or Pb. Data were analyzed for biomass production and chlorophyll synthesis. Results indicate that there was a dose related inhibition of plant biomass, chlorophyll concentration, and chlorophyll content in several Cd and Pb treated plant groups. Results also indicate that these inhibitions were greater in the Cd treated plants than in the Pb treated groups, suggesting that either Cd is more toxic to plant tissue than the Pb, or Cd is more mobile in soil/plant tissue than the Pb, therefore, capable of exerting a more toxic effect. Acknowledgements: The study was supported by a grant from NIH/NIGMS/MBRS (# 5-S06-GM55356-03). The author s acknowledge Dr. Susmita Ghosh, Department of Biology, Jackson State University, for her assistance. EVALUATION OF DIFFERENT PLANT SPECIES FOR PHYTOEXTRACTION OF CADMIUM FROM CONTAM CONTAM Contamination CONTAM Contaminate CONTAM Committee On Nationwide Television Audience Measurement 1NATED SOILS K. Seals [*], M.F.T. Begonia, G.B. Begonia, G. Miller, V. Payne [*], and M. Brown, Jackson State University, Jackson, MS 39217 The success of phytoextraction as a phytoremediation strategy for clean up of metal-contaminated soils depends on the selection of suitable species that not only produce large biomass but also accumulate and tolerate toxic metals. An experiment was therefore conducted at a Jackson State University laboratory equipped with high intensity (1000 W; PAR, 800 [micro]mol photons M [-2] S [-1]) metal halide lamps. Five plant species were evaluated for their tolerance and uptake of cadmium when grown on cadmium-contaminated media. Seeds of selected species [momingglory (Ipomoea lacunosa L.), coffeeweed (Sesbania exaltata Raf.), wheat (Triticum aestivum L.), rape (Brassica napus L.), turnip turnip, garden vegetable of the same genus of the family Cruciferae (mustard family) as the cabbage; native to Europe, where it has been long cultivated. The two principal kinds are the white (Brassica rapa) and the yellow (B. (Brassica campestris rap ifera L.)] were planted in 150 [cm.sup.3] plastic super cells containing sand. Each super cell with emerged seedlings was irrigated alternately with 10 ml of either nutrient solution or aqueous cadmium test solution every three days until harvest. Three super cells each containing two or five plants consti tuted a treatment replicate. Treatments were arranged in a completely randomized design (CRD CRD See Central Registration Depository (CRD). ) with three replications. Generally, shoot and root dry biomass of the test species decreased with increasing concentration of applied cadmium, although cadmium tolerance varied among test species. Wheat and rape showed the greatest and least tolerance to cadmium, respectively. The relative uptake of cadmium by the shoots and roots of each test species will be explained in relation to the species' tolerance to cadmium. 2:00 Divisional Talks Resume 2:00 PESTICIDE RESIDUES IN LEGUMINOUS le·gu·mi·nous adj. 1. Of, belonging to, or characteristic of the family Leguminosae, which includes peas, beans, clover, alfalfa, and other plants. 2. Resembling a legume. PLANTS: ASSIMILATION OR DEPOSITION? Detria Smith [*], Joseph M. Wahome, and William C. Mahone, Mississippi Valley State University, Itta Bena, MS 38941 The presence of pesticide residues on bean and pea plants was quantified using High Performance Liquid Chromatography High-performance liquid chromatography (HPLC) is a form of column chromatography used frequently in biochemistry and analytical chemistry. It is also sometimes referred to as high-pressure liquid chromatography. (HPLC). The plants were grown in replicates under different environmental conditions and sprayed with a phosphate based pesticide at regular time intervals. The amount of pesticide residues in plants depended on the growth stage and inter-spraying intervals. These data are discussed in light of environmental contamination of food chains. 2:15 APPLICATIONS OF IMAGE ANALYSIS IN PLANT PATHOLOGY Kenneth J. Curry and Reena Shetty [*], University of Southern Mississippi, Hattiesburg, MS 39406-5018 Frequently, disease symptoms in plants are assessed by subjective evaluation which may be a tedious and time consuming process. Image analysis promises an alternative to the traditional method that can be rapid and precise. With image analysis a computer assesses and quantifies disease symptoms in terms of color patterns and areas. We are using the Bioquant [TM] image analysis software package. We have analyzed anthracnose anthracnose Plant disease of warm humid areas, caused by a fungus (usually Colletotrichum or Gloeosporium). It infects various plants, from trees to grasses. Symptoms include sunken spots of various colours in leaves, stems, fruits, or flowers, often leading to wilting and leaf spots and found that the lesions are easily distinguished from the healthy leaf tissue. Variation in the color is the basis for quantification. With this software, a relatively large number of samples can be quantified in a short period of time. Image analysis is not restricted to leaves but can be extended to quantifying the disease symptoms in whole fruits and grains. If the infected grains are darker or lighter in color than the healthy ones, they can be easily distinguished and quantified in terms of color pattern and number. This could be useful in a variety of ways in the agricu ltural industry. Despite the advantages, there are certain limitations to image analysis. Since quality and uniformity of lighting is important in comparative quantification, it is imperative that the sample be viewed under controlled lighting conditions and this puts a limit to its use in the field where the lighting conditions are variable. 2:30 A PRELIMINARY STUDY OF THE FUNGUS CERCOSPORELLA RUBI IN BLACKBERRY (RUBUS SP.) Melinda R. Lyman [1][*], Kenneth J. Curry [1], and Barbara J. Smith [2], (1.) University of Southern Mississippi, Hattiesburg, MS 39406-5018 and (2.) Agricultural Research Service, Small Fruits Research, Poplarville, MS 39470-2005 Symptoms of infection by this fungus include rosetted vegetative buds and elongated floral buds that are reddish in color. When the floral bud is fully mature, the sepals and petals open exposing infected pistils and stamens. Cercosporella rubi sporulates at this time and apparently infects neighboring primocanes. Infected flowers abort and infected primocanes continue to grow without any symptoms. During the early stages of floral bud development, C. rubi occupies the tight crevices among stamens and pistils. My observations confirm Plakidas' (1937) report that this fungus becomes enclosed in the carpel carpel One of the leaflike, seed-bearing structures that constitute the innermost whorl of a flower. One or more carpels make up the pistil. Fertilization of an egg within a carpel by a pollen grain from another flower results in seed development within the carpel. during ovule ovule (o´vul) 1. the oocyte within the graafian follicle. 2. any small, egglike structure. o·vule n. 1. A small or immature ovum of a mammal. 2. development while never penetrating host tissue. Samples have been collected from vegetative and floral buds at various stages of development and embedded in paraffin and plastic. Paraffin sections of infected floral buds have yielded no information to date as to the presence of C. rubi. However, plastic embedded floral buds on both light and electron microscopic levels have shown presence of C. rubi nestled within tight crevices among pistils and stamens and within closing ovules. In addition, mycelium mycelium Mass of branched, tubular filaments (hyphae) of fungi (see fungus) that penetrate soil, wood, and other organic matter. The mycelium makes up the thallus (undifferentiated body) of a typical fungus. of this fungus grows in a matrix of unknown composition which appears granular at the ultrastructural level. Mycelium of C. rubi is evident in floral buds as small as 1mm in diameter. At the ultrastructural level, host cells have no apparent symptoms of stress although the fungal matrix adheres to the cuticle cuticle /cu·ti·cle/ (ku´ti-k'l) 1. a layer of more or less solid substance covering the free surface of an epithelial cell. 2. eponychium (1). 3. a horny secreted layer. of host tissues. Mycelium has not been observed in vegetative buds at this time. Additional observations will be made as the season progresses and as vegetative buds show evidence of infection. 2:45 ULTRASTRUCTURAL LOCALIZATION OF CHITIN IN FUNGUS COLLETOTRICHUM ACUTATUM IN STRAWBERRY USING WHEAT GERM AGGLUTININ Agglutinin A substance that will cause a clumping of particles such as bacteria or erythrocytes. Of major importance are the specific or immune agglutinins, which are antibodies that will agglutinate bacteria containing the corresponding antigens on their (LECTIN lectin /lec·tin/ (lek´tin) any of a group of hemagglutinating proteins found primarily in plant seeds, which bind specifically to the branching sugar molecules of glycoproteins and glycolipids on the surface of cells. ) Jana B. Avant [1][*], Kenneth J. Curry [1], and Barbara J. Smith [2], (1.) University of Southern Mississippi, Hattiesburg, MS 39406-5018 and (2.) Agricultural Research Service, Small Fruits Research, Poplarville, MS 39470-2005 Understanding the details of molecular interactions between plant pathogens and their host has been greatly assisted by the development of techniques to localize and visualize molecules in planta using lectins Lectins A class of proteins of nonimmune origin that bind carbohydrates reversibly and noncovalently without inducing any change in the carbohydrate. Lectins bind a variety of cells having cell-surface glycoproteins (carbohydrate bound proteins) or glycolipids , antibodies, and enzymes associated with gold, flourescent, and other labels. The lectin, wheat germ agglutinin, has been used successfully in studies on chitin distribution in fungal walls. Wheat germ agglutinin has a binding site for a glucosamine glucosamine /glu·co·sa·mine/ (gloo-ko´sah-men) an amino derivative of glucose, occurring in glycosaminoglycans and a variety of complex polysaccharides such as blood group substances. molecule of at least two or three residues and requiring an uncharged substituent substituent /sub·stit·u·ent/ (-stich´u-ent) 1. a substitute; especially an atom, radical, or group substituted for another in a compound. 2. of or pertaining to such an atom, radical, or group. in the 2-position (which is the structure of chitin). Chitin is a substrate for plant chitinases and is known to elicit host defense responses. 'Chandler' cultivar of strawberry was inoculated with Colletotrichum acutatum and observed for lesion development. Appropriate tissue was fixed, resin embedded, and sectioned for electron microscopy. Chitin was visualized using wheat germ agglutinin conjugated with colloidal gold. The gold probe indicated the distribution of chitin wit hin the mature fungal walls C. acutatum. Several fungi are known to modify or mask chitin in certain penetration structures presumably pre·sum·a·ble adj. That can be presumed or taken for granted; reasonable as a supposition: presumable causes of the disaster. to avoid detection from the host or to avoid the effects of host chitinases. Studying the distribution of chitin fungal invasion is a necessary part of understanding the intrinsic host-pathogen relationship. We intend to use this technique to determine the distribution of chitin within walls of the invasion structures of C. acutatum. 3:00 ANTHRACNOSE DISEASE IN STRAWBERRY (FRAGARIA X ANANASSA) CAUSED BY COLLETOTRICHUM ACUTATUM AND COLLETOTRICHUM FRAGARIAE: AN ULTRASTRUCTURAL STUDY Maritza Abril [1][*], Kenneth J. Curry [1], and Barbara J. Smith [2], (1.) University of Southern Mississippi, Hattiesburg, MS 39406-5018 and (2.) Agricultural Research Service, Small Fruits Research, Poplarville, MS 39470-2005 Colletotrichum acutatum is found worldwide on a number of strawberry hosts, and is increasing in importance as the cause of strawberry petiole petiole /pet·i·ole/ (pet´e-ol) a stalk or pedicle. epiglottic petiole the pointed lower end of the epiglottic cartilage, attached to the thyroid cartilage. , stolon stolon or runner Slender stem that grows horizontally along the ground, giving rise to roots and aerial (vertical) branches at specialized points called nodes. Many annual and perennial grasses have creeping stolons (e.g., bent grass). , crown, and root infections. Colletotrichum fragariae is often associated with anthracnose crown rot in strawberry and seems to be restricted to the southeastern United States, while C. acutatum is usually the causal agent of anthracnose fruit rot. These pathogens infect strawberry petioles and stolons and cause the dark sunken lesions typical of anthracnose. We inoculated petioles and stolons by misting with conidial suspensions (1 .5x [10.sup.6] spores/ml) of C. acutatum and C. fragariae and incubating at 28[degrees]C and 32[degrees]C respectively and 100% RH. We observed at the light as well as the ultrastructural level the ontogeny ontogeny: see biogenetic law. Ontogeny The developmental history of an organism from its origin to maturity. It starts with fertilization and ends with the attainment of an adult state, usually expressed in terms of both maximal body of the infection process by both pathogens on the 'Chandler' strawberry cultivar. Following cuticular penetration via an appressorium, subsequent steps of invasion by both C. acutatum and C. fragariae involve growth within the cuticle and within the cell walls of epidermal, subepidermal, and subtending cells. Both fungi have a necrotrophic nature, but occasionally they are seen penetrating living cells. Acervuli acervuli calcified granules sometimes found in the pineal body and choroid plexus, especially in horses; structure similar to hydroxyapatite crystals; appear to have glial or stromal origin. Called also brain sand, corpora arenacea, psammoma bodies. (the reproductive structures) are formed once the cortical tissue has experienced moderate disruption and begins with the development of a stroma stroma /stro·ma/ (stro´mah) pl. stro´mata [Gr.] the matrix or supporting tissue of an organ.stro´malstromat´ic stro·ma n. pl. stro·ma·ta 1. in the tips of the epidermal cells. The acervuli develop under the cuticle of the host and erupt through the cuticle to produce conidia co·nid·i·a n. Plural of conidium. . Invasion of the vascular tissue apparently occurs after acervulus a·cer·vu·lus n. pl. a·cer·vu·li See brain sand. acervulus pl. acervuli [L.] sandy calcifications in or about the pineal body and choroid plexus. maturation and remains minimal. 3:15 Break 3:30 POTENTIAL NUTRACEUTICALS FROM SOUTHEASTERN FRUITS AND PROCESSES TO OBTAIN THEM Juan L. Silva[1][*], Aurora E. Nuflez [2], Diane K. Tidwell [3], Miranda Reed [1], and S.X. Ma [4], (1.) Mississippi State University, Mississippi State, MS 39762; (2.) Universidad De Oriente The University of Oriente Venezuela (Spanish: Universidad de Oriente Venezuela, UDO) is a university located in Eastern Venezuela. The university has 5 campuses located in the states of Sucre, Anzoategui, Monagas, Bolivar, and Nueva Esparta. , Maturin, Venezuela; University of Mississippi The University of Mississippi, also known as Ole Miss, is a public, coeducational research university located in Oxford, Mississippi. Founded in 1848, the school is composed of the main campus in Oxford and three branch campuses located in Booneville, Tupelo, and Southaven. , Oxford, MS 38655; and (4.) Minute Maid Corporation, Orlando, FL 32802 Nutraceuticals are substances that are found in foods and contribute to human health through disease prevention, curing, or health maintenance. These could range from food concentrates to extracts, usually from plant materials. One sector is the antioxidants used to "neutralize" free radicals in our body and thus prevent cancer and other diseases. One group of these are the phytochemicals, a group of minor chemicals found in plants that may or may not have health benefits. One sector within these are the phytoestrogens Phytoestrogens Compounds found in plants that can mimic the effects of estrogen in the body. Mentioned in: Premenstrual Syndrome phytoestrogens, n.pl plant-derived estrogen analogs. and another the polyphenols. Amongst the first are isoflavones isoflavones (īˑ·sō·flāˈ·vōnz), n.pl phytoestrogenic compounds found in various plants, including red clover and soy. , resveratrol res·ver·a·trol n. A natural compound found in grapes, mulberries, peanuts, and other plants or food products, especially red wine, that may protect against cancer and cardiovascular disease by acting as an antioxidant, antimutagen, and and ellagic acid, whereas catechins and oligomeric proanthocyanidins make-up the latter. Phytoestrogens bind to the body much as estrogen does. Resveratrol has been found in grapes, seeds, juice, wine, and other products but is also found in blueberries. It is also associated with decreased risk of coronary heart disease coronary heart disease: see coronary artery disease. coronary heart disease or ischemic heart disease Progressive reduction of blood supply to the heart muscle due to narrowing or blocking of a coronary artery (see atherosclerosis). . Southern grapes (muscadines - Vitis rotundifolia) and blueberries (rabbiteye - Vaccinium ascei) ha ve thicker skin than their Northern or European counterparts. Data has shown that these fruits and their seeds contain elevated amounts of resveratrol and phenolics, and that muscadines also contain ellagic acid. Processes to concentrate and extract these compounds include dehydration and milling of the seeds and skins and liquid-liquid extraction from spent materials. Products such as wine, by-products from puree and skin, and others have also been developed. These products, from mnuscadines and rabbitteye blueberries contain as much as twice to five times as much resveratrol and other phenolics than their counterparts. 3:45 SURVIVAL OF ESCHERICHIA COLI DURING THE MANUFACTURE AND STORAGE OF CHEESE CURDS UNDER MODIFIED ATMOSPHERE PACKAGING Eric A. Johnson [1][*], Kathleen Glass [1], and Kendra J. Thornton [2], (1.) University of Wisconsin-Madison “University of Wisconsin” redirects here. For other uses, see University of Wisconsin (disambiguation). A public, land-grant institution, UW-Madison offers a wide spectrum of liberal arts studies, professional programs, and student activities. and (2.) Mississippi State University, Mississippi State, MS 39762 The objective of this study was to compare the survival of Escherichia coli O157:H7 during the manufacture of Cheddar cheese curd packaged under ambient air, 100% [CO.sub.2], 100 [N.sub.2], or 60% [CO.sub.2]/40% [N.sub.2] mixture and stored at 21.1, 12.8, and 4.2[degrees]C (70, 55, and 40[degrees]F). The E. coli strain F5854 was obtained from cheese associated with the 1998 Wisconsin cheese curd outbreak. Pasteurized pas·teur·ize tr.v. pas·teur·ized, pas·teur·iz·ing, pas·teur·iz·es To subject (a beverage or other food) to pasteurization. pas , nonhomogenized whole milk was obtained from the University of Wisconsin-Madison Dairy Plant. Cheese curds were produced using standard cheese make procedures. F5854 was added at the beginning of processing. The curds were salted to approximately 1.5% and weighed into 20 g portions and placed in either sterile vacuum bags or stomacher bags. Samples from each gas and ambient air were incubated. Sampling was performed on Day 0, 1, 2, and 3 for all temperatures. 21.1 [degrees]C were discontinued because obvious spoilage spoilage decomposition; said of meat, milk, animal feeds especially ensilage. would occur. In addition, sampling was performed on day 4, 7, 10, 14, 21, and 2 8 for 12.8[degrees]C and 4.2[degrees]C. No significant difference was noted among gases and ambient air in 21 [degrees]C curds. However, there were significant differences in the 4[degrees]C and 12[degrees]C curds. 4:00 USE OF HIGH INTENSITY PULSED-LIGHT ON CHANNEL CATFISH FILLETS Juan L. Silva [*], Jose E. Figueroa, and Abdulaziz Shuwaish, Mississippi State University, Mississippi State, MS 39762 Processing of this fish grew from 2.7 million kg in 1970 to 68.2 million kg in 1984 to 256 million kg in 1998. Fresh fish fillets account for about 20% of total product sales with 18% more in other fresh products. Consumer demand coupled with longer distribution channels place demands on the quality/shelf-life and safety of this product. New and improved technologies can help in per capita consumption of channel catfish (Ictalurus punctatus) has risen over 0.46 kg per capita in 1 998 meeting these demands. One such technology is pulsed-light, short-duration, high intensity light with wavelengths from UV to the IR region. This technology has very little heat production but is effective against spoilage and pathogenic bacteria. This enhances the shelf-life and safety of prepackaged pre·pack·age tr.v. pre·pack·aged, pre·pack·ag·ing, pre·pack·ag·es To wrap or package (a product) before marketing. Adj. 1. catfish products held at refrigeration temperatures. Freshly processed channel catfish fillets were exposed to the PureBright [R] light, 20,000X more intense than sunlight with wavelengths of 200-300 nm. The doses ranged between 0.25 and 0.50 J/[cm.sup.2], with 2 and 4 pulses for each dose. The prepackaged fish were treated one day after processed and evaluated for 13 d at 4[degrees]C. Psychrotrophs (PPC) increased from 3.2 to 6.0 CFU/g by day 9 for control versus 11-12 days for treated fillets. Surface color and texture (firmness) were not different between the treatments. Oxidation nor gaping were different between treatment or time. This technology my enhance shelf-life of catfish fillets by 3-4 days kept at 4[degrees]C. 4:15 Divisional Business Meeting |
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