Source: AGRICULTURAL RESEARCH SERVICE submitted to
FIELD SCALE DEMONSTRATION/VALIDATION STUDIES OF ALTERNATIVES FOR METHYL BROMIDE IN PLASTIC MULCH
Sponsoring Institution
Agricultural Research Service/USDA
Project Status
TERMINATED
Funding Source
Reporting Frequency
Annual
Accession No.
0403245
Grant No.
(N/A)
Project No.
6618-22000-023-00D
Proposal No.
(N/A)
Multistate No.
(N/A)
Program Code
(N/A)
Project Start Date
Apr 13, 2000
Project End Date
Jul 28, 2004
Grant Year
(N/A)
Project Director
CHELLEMI D O
Recipient Organization
AGRICULTURAL RESEARCH SERVICE
219 SOUTH ROCK ROAD
FT PIERCE,FL 34945
Performing Department
(N/A)
Non Technical Summary
(N/A)
Animal Health Component
100%
Research Effort Categories
Basic
0%
Applied
100%
Developmental
0%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
2121460106018%
2121460110017%
2121460112018%
2121460116017%
2131122102010%
2131420116010%
2131461102010%
Goals / Objectives
EVALUATE AND VALIDATE THE EFFECTIVENESS, ECONOMIC VIABILITY AND ENVIRONMENTAL IMPACT OF ALTERNATIVES TO METHYL BROMIDE SOIL FUMIGATION FOR NEMATODE DISEASE, AND WEED CONTROL IN PLASTIC MULCH VEGETABLE PRODUCTION SYSTEMS IN FLORIDA.
Project Methods
ESTABLISH ALTERNATIVE TREATMENTS IN PRODUCTION FIELDS WITH A PRIOR HISTORY OF SOILBORNE PESTS AND DECLINING YIELDS AND AT A SCALE SUFFICIENT TO ALLOW THEIR EVALUATION AS COMPONENTS OF COMMERCIAL SYSTEMS. DETERMINE THE EFFECTS OF ALTERNATIVE TREATMENTS ON SOILBORNE DISEASES, PLANT PARASITIC NEMATODES AND COMPETITION FROM WEEDS. HARVEST PLOTS AND COLLECT YIELD DATA USING USDA GRADING STANDARDS. MEASURE THE IMPACTS OF ALTERNATIVE TREATMENTS ON KEY INDICATORS OF SOIL QUALITY AND BIOLOGICAL DIVERSITY.

Progress 04/13/00 to 07/28/04

Outputs
1. What major problem or issue is being resolved and how are you resolving it (summarize project aims and objectives)? How serious is the problem? What does it matter? Methyl bromide is a highly efficacious fumigant used on more than 100 crops to control insects, nematodes, weeds and pathogens. Methyl bromide has been implicated as a major destroyer of stratospheric ozone and a complete phase-out of production and sale in the U.S. by the year 2005 is required. Chemical alternatives including combinations of 1,3 dichloropropene, chloropicrin, pebulate and napropamide have been identified as potential alternatives. Use of soil solarization in combination with resistant cultivars, organic amendments, biological control agents or the aforementioned chemicals has also been identified as a potential replacement to methyl bromide. None of the potential alternatives provide the same broad-spectrum level of control as methyl bromide across all cropping systems or environmental conditions. Additionally, the alternatives will require some modification in crop production practices by growers. U.S. tomato, pepper and strawberry growers account for 39 percent of the domestic consumption of methyl bromide and 12 percent of the global consumption. In Florida alone, tomato and pepper growers account for 25 percent of the domestic production. Florida is the nations leading producer of fresh market tomato and pepper. During the 1997-98 crop, valued in excess of $745 million, methyl bromide was used to treat over 90 percent of the 59,200 acres planted. Without methyl bromide, production of tomato and pepper in Florida has been estimated to decline by 61.4 percent and 63.5 percent, respectively. This translates to nearly a $400 million loss in revenue for Florida producers alone. The development of alternatives to methyl bromide has been designated an area of high priority to Agricultural Research Service (ARS) and activities are coordinated under ARS National Program 308 - Methyl Bromide Alternatives. One of the objectives of National Program 308 is to develop multiple management strategies for soil borne pests. The objectives of this CRIS are to test existing alternative fumigants in long-term field trials, to develop new technologies for weed control, including biological control agents, and to develop a set of procedures to assess soils for their ability to provide resistance or suppressiveness to nematode and fungal pathogens. 2. List the milestones (indicators of progress) from your Project Plan. There is no project plan for this CRIS. Long-term field validation studies will be completed. Data from this project will be compiled and reported. The biological control fungus, Alternaria destruens will be field tested for control of the emerging weed problem, Cuscuta pentagona. Reduced-risk herbicides will be tested in combination with Alternaria destruens to provide an integreated approach to controlling this weed. Manuscripts will be prepared from this work and extension publications will be prepared to disseminate the information. Field studies on Dactylaria higginsii and laboratory studies on pesticide compatibility with this fungus will be completed. In relation to the identification of indicators of soils suppressive to nematodes and diseases, first year milestones included identification and hiring of a graduate student, development of a research plan and plan of study, and initial training in specific molecular techniques for quantifying and characterizing microbial and nematode populations in soil. Second year milestones will include the establishment of field and greenhouse trials and assessment of soil environments common to vegetable production systems that are suppressive to pathogens and root-knot nematodes and encouraging or neutral to vegetables and non-target organisms. Third year milestones will be replication of field and greenhouse trials and data analysis. Fourth year milestones will be presentation and publication of data on the effects of alternative production practices on nematodes, pathogens and beneficial soil communities. 3. Milestones: A. Field trials were conducted using the dodder biological control agent, Alternaria destruens, at the Header Canal Farm Site. Greenhouse studies were initiated on the evaluation of glyphosate, ammonium sulfate, and the combination of these materials with Alternaria destruens for control of dodder. The long-term alternative fumigant study was completed and data is being compiled. Manuscripts on the nutsege biological control agent, Dactylaria higginsii are currently in preparation. During the past year, project plans were detailed, a graduate student was hired, and technical training in PCR-based techniques for monitoring populations of biocontrol agents and endemic microorganisms in the rhizosphere was completed related to the project identifying indicators of soil suppressiveness against nematodes and pathogens. B. List the milestones (from the list in Question #2) that you expect to address over the next 3 years (FY 2005, 2006, & 2007). What do you expect to accomplish, year by year, over the next 3 years under each milestone? 2005-There are no additional milestones for the long-term alternative fumigant study as the experiment has been completed. Greenhouse studies on Alternaria destruens in combination with glyphosate and ammonium sulfate will be continued. Manuscripts on Dactylaria higginsii will be submitted. Establishment of field and greenhouse trials and assessment of soil environments common to vegetable production systems that are suppressive to pathogens and root-knot nematodes and encouraging or neutral to vegetables and non-target organisms. 2006-Greenhouse and field trials will be completed on Alternaria destruens and publications will be prepared. Replication of field and greenhouse trials and data analysis of the soil suppressiveness against nematodes and pathogens. 2007-There are no additional milestones for the weed biological control project as it will be completed in 2006. Presentation and publication of data on the effects of alternative production practices on nematodes, pathogens and beneficial soil communities. 4. What were the most significant accomplishments this past year? A. Single most significant accomplishment during FY 2004 (one per Research (OOD) Project): Two promising alternatives to methyl bromide (MBr) are 1,3- dichloropropene (1,3-D) + chloropicrin (Pic) + pebulate and solarization. These treatments [1,3-D + 17% Pic + pebulate (alone or with the herbicide napropamide) and 7 to 8 weeks of solarization in combination with the biological control agent Gliocladium virens or napropamide], applied annually from 1998 to 2001 for fall tomato, were compared with MBr + Pic and a non-treated control for residual pest control the following spring in three cropping systems: double-cropped cucumber (Cucumis sativus L.), a millet (Panicum ramosum L.) cover crop, and fallow. By the end of the spring season, populations of nutsedges (Cyperus sp.) and nematodes with 1,3-D + 17% Pic + pebulate were similar to those with MBr + Pic in most years. Solarization performed as well as 1,3-D + Pic + pebulate against nutsedge in spring cucumber, but this may have been due to applications of paraquat in solarized plots where nutsedge had emerged prior to planting each fall tomato crop. Nematodes were controlled more consistently following 1,3-D + Pic + pebulate than with solarization. Cucumber fruit production was similar with 1,3-D + Pic + pebulate and MBr + Pic each year, whereas solarization resulted in yields equivalent to MBr + Pic in only two of the four years. Pest resurgence in spring was similar following fall-applied 1,3-D + Pic + pebulate and MBr + Pic. B. Other significant accomplishment(s), if any. None C. Significant activities that support special target populations. None D. Progress Report opportunity to submit additional programmatic information to your Area Office and NPS (optional for all in-house (D) projects and the projects listed in Appendix A; mandatory for all other subordinate projects). Glyphosate studies were conducted during the summer of 2003 using plants parasitized with vegetatively propagated C. pentagona. There were six treatments including control, glyphosate at 0.25%, glyphosate at 0.50%, glyphosate at 1.0%, glyphosate at 2.0%, and glyphosate at 4.0%. By 2 WAT, dodder treated with 2% and 4% glyphosate exhibited 100% injury, while untreated dodder was slightly injured (ca. 26% injury). By 5 WAT, all dodder plants treated with glyphosate were dead and untreated dodder was 95% dead. When comparing slopes, there were no differences between treatments of glyphosate at 4% and 2%; 1% and 2%; and 0.5% and 0.25%. Ammonium sulfate studies were conducted during the summer of 2003 using plants parasitized with C. pentagona. There were seven treatments including control, ammonium sulfate at 1, 2, 3, 4, 5, and 10%. In the first study, there were no differences in concentrations of ammonium sulfate applied at 1% to 10%. Although there was a difference between the untreated control and ammonium sulfate applied at 1%. Based on results from the previous studies, greenhouse studies were conducted using different concentrations of glyphosate and ammonium sulfate with A. destruens. These studies are currently underway. 5. Describe the major accomplishments over the life of the project, including their predicted or actual impact. The impact of soil fumigants and spring cropping practices on soilborne pest control and growth of fall-grown fresh market tomato were studied over a 5 year period from 1998 to 2002. Soil fumigant treatments [non- treated, 67% methyl bromide (MBr) + 33% chloropicrin (Pic), 83% 1,3- dichloropropene (1,3-D) + 17% Pic + the herbicide pebulate (with the herbicide napropamide from 2000 to 2002), and soil solarization (with napropamide from 2000 to 2002)] were applied 3 to 8 weeks prior to tomato planting and followed by a spring crop of cucumber, millet, or fallow. Nutsedge (Cyperus esculentus L. and C. rotundus L.) populations, relative to those with non-treated soil, were reduced equally with 1,3-D + Pic + pebulate and MBr + Pic in four of five seasons. Solarization provided similar nutsedge control as MBr + Pic in two of five seasons. Fusarium wilt race 3 (incited by Fusarium oxysporum f. sp. lycopersici) infected 32% to 78% of the tomato plants grown in non-treated soil, and MBr + Pic and 1,3-D + Pic + pebulate reduced incidences similarly and to a greater extent than solarization. Indices of root galling by root knot (Meloidogyne sp.) nematodes and nematode populations were generally lower and similar with the two fumigants than solarization. Marketable tomato yields were generally highest and similar with 1,3-D + Pic + pebulate and MBr + Pic, intermediate with solarization, and lowest with non-treated soil. Spring cropping practice had little influence on pest populations and tomato growth the following falls. The repeated use of 1,3-D + Pic + pebulate in the same field, during five consecutive cropping seasons, did not result in a reduction of soilborne pest control or tomato production below that with MBr + Pic. 6. What science and/or technologies have been transferred and to whom? When is the science and/or technology likely to become available to the end- user (industry, farmer, other scientists)? What are the constraints, if known, to the adoption and durability of the technology products? Six commercial scale of-farm field trials demonstrated to growers the performance of selected herbicides, alone and in combination, when used as part of an alternative program based on Telone C-35 broadcast application. Field days were conducted at multiple on-farm research sites. 7. List your most important publications in the popular press and presentations to organizations and articles written about your work. Cook, J., Charudattan, R., Rosskopf, E., Zimmerman, T, MacDonald, G., and Stall, W. 2004. Integrated control of dodder (Cuscuta pentagona) using glyphosate, ammonium sulfate, and the biological control agent Alternaria destruens. Proceedings of the Florida Weed Science Society, p.3. Cook, J. (speaker) Charudattan, R., Rosskopf, E., Zimmerman, T, MacDonald, G., and Stall, W. 2004. Integrated control of dodder (Cuscuta pentagona) using glyphosate, ammonium sulfate, and the biological control agent Alternaria destruens. Caribbean Food Crops Society Meeting, July 20, 2004, Saint John, Virgin Islands.

Impacts
(N/A)

Publications

  • Morales-Payan, J. P., Rosskopf, E. N., Yandoc, C. B., Semidey, N., Charudattan, R., Stall, W. M., DeValerio, J. T. Pathogens and their potential for biocontrol of nutsedges (Cyperus rotundus L. and C. esculentus L.): An overview with an emphasis on the fungus Dactylaria higginsii. Proceedings International Symposium on Biological Control of Weeds, Sonora, Mexico. 2002. p. 25-31.
  • Gilreath, J. P., Mirusso, J. M., Jones, J. P., Rosskopf, E. N., Noling, J. W., Gilreath, P. R. Efficacy of broadcast Telone C-35 in tomato. Proceedings Annual International Research Conference on Methyl Bromide Alternatives and Emissions Reductions. 2002. p. 19-1-2. MBAO.


Progress 10/01/02 to 09/30/03

Outputs
1. What major problem or issue is being resolved and how are you resolving it? Methyl bromide is a highly efficacious fumigant used on more than 100 crops to control insects, nematodes, weeds and pathogens. In Florida, it is considered essential for tomato and pepper production. Methyl bromide has been implicated as a major destroyer of stratospheric ozone and a complete phase-out of production and sale in the U.S. by the year 2005 is required. Chemical alternatives including combinations of 1,3 dichloropropene, chloropicrin, pebulate and napropamide have been identified as potential alternatives. Use of soil solarization in combination with resistant cultivars, organic amendments, biological control agents or the aforementioned chemicals has also been identified as a potential replacement to methyl bromide. None of the potential alternatives provide the same broad-spectrum level of control as methyl bromide across all cropping systems or environmental conditions. Additionally, the alternatives will require some modification in crop production practices by growers. To ensure that the performance of methyl bromide alternatives is evaluated under a diverse set of cropping systems and to provide growers with experience use of these alternatives, large-scale demonstration/validation studies were initiated in Fiscal Year 1996. The objectives of this CRIS are to: 1) evaluate the biological and economic implications of methyl bromide alternatives when applied by growers in large quantities under diverse cropping systems; 2) provide growers with opportunities to evaluate alternatives prior to the complete phase-out of methyl bromide. 2. How serious is the problem? Why does it matter? U.S. tomato, pepper and strawberry growers account for 39 percent of the domestic consumption of methyl bromide and 12 percent of the global consumption. In Florida alone, tomato and pepper growers account for 25 percent of the domestic production. Florida is the nations leading producer of fresh market tomato and pepper. During the 1997-98 crop, valued in excess of $745 million, methyl bromide was used to treat over 90 percent of the 59,200 acres planted. Without methyl bromide, production of tomato and pepper in Florida has been estimated to decline by 61.4 percent and 63.5 percent, respectively. This translates to nearly a $400 million loss in revenue for Florida producers alone. 3. How does it relate to the National Program(s) and National Program Component(s) to which it has been assigned? The development of alternatives to methyl bromide has been designated an area of high priority to Agricultural Research Service (ARS) and activities are coordinated under ARS National Program 308 ' Methyl Bromide Alternatives. One of the objectives of National Program 308 is to develop multiple management strategies for soil borne pests. Pest management strategies are consistent with ARS Strategic Plans that call for development of agricultural systems that are highly competitive in the global market and protect natural resources and the environment. 4. What were the most significant accomplishments this past year? The long-term affects of using alternative fumigants for control of soil borne pests are unknown. A five year study was conducted wherein Telone C-17, a broad-spectrum fumigant plus herbicides and Solarization (heating of the soil using solar radiation on clear plastic mulch) plus herbicide, were compared to methyl bromide and an untreated control for management of soil borne diseases, nematodes and weeds in fall tomatoes, which were followed by 3 spring cropping options: 1) double cropped cucumbers, 2) millet cover crop and 3) fallow at the University of Florida, Gulf Coast Research and Education Center, Bradenton, FL. Soil borne pest control and crop yields were similar to methyl bromide with Telone C-17 plus herbicide and intermediate between methyl bromide and the untreated control with solarization plus herbicide in fall tomato and production of double cropped cucumber in the spring of 2003 was not reduced with solarization or Telone C-17 plus herbicide when compared to methyl bromide, unlike previous years when cucumber production with solarization was about one-half of that provided by methyl bromide. Results of this study dispel the widely held belief that repeated use of Telone C-17 plus herbicide over a period of years will result in increased soil borne pest problems, thus removing one of the stumbling blocks to Telone C-17 as a replacement for methyl bromide and suggesting that other effective chemical alternatives may provide similar results. B.Other Significant Accomplishment(s), if any: Florida tomato growers have limited experience with application of preplant incorporated herbicides and use of Telone C-35, a broad-spectrum fumigant, as an alternative to methyl bromide, therefore this project was conducted to demonstrate the proper selection and application of herbicides in combination with broadcast application of Telone C-35 and familiarize them with the nuances of herbicide application in large plots on their farms. Large plot (2 to 10 acre), replicated field trials were conducted at 6 farms in the Palmetto - Ruskin production area during the spring and fall of 2002 and spring 2003, utilizing labeled, preplant, soil incorporated herbicides in combination with Telone C-35 applied broadcast in cooperation with the University of Florida, Bradenton. Soil borne pest control was similar to methyl bromide with these alternatives in the spring and fall of 2002, but spring 2003 trials provided very different results with poor nutsedge control observed in both trials following broadcast application of an herbicide plus Telone C-35 followed by in bed application of chloropicrin. Direct involvement with field validation / demonstration trials has improved grower understanding and acceptance of Telone C-35 plus herbicides as a methyl bromide alternative and allows for grower recognition of the importance of proper herbicide application and incorporation techniques. Acceptance of biological control as a viable weed control method requires incorporation into an integrated approach to crop production. Field trials, in cooperation with University of Florida, Gainesville were completed at the Header Canal Farm Site, USDA to evaluate Dactylaria higginsii, a biological control agent, for control of nutsedge in an off- season weed management program and in a crop production setting combined with Telone C-35, a broad-spectrum soil fumigant and compared to the fumigant and an herbicide. There was no difference in tomato yield attributable to fallow season treatments and overall tomato yield from fumigant plus fungus-treated plots was statistically equivalent to yields achieved in the fumigant plus herbicide-treated plots. Commercial availability of the biological control agent could enhance the number of options for control of nutsedge in the absence of methyl bromide. The role of cover crops for herbicidal management of nutsedge and nematodes during fallow periods as part of an overall management strategy for a wide range of crops, especially those with no herbicide options for use during the cropping season, has been only minimally explored. Cowpea, sorghum and millet were planted in nutsedge-infested fields and the effects of these crops were determined on soil borne pest levels at the University of Florida, Gulf Coast Research and Education Center in Bradenton, FL. Nutsedge populations increased with millet as the cover crop, remained approximately the same with sorghum and decreased with cowpeas, while sting nematodes increased with all three. Successful off- season management of nutsedge and nematodes through the use of cover crops and limited applications of herbicide would provide a much needed means of control of these pests which would not be limited by crop toxicity and labeling restrictions and would thereby be available options for a wide range of crop producers. Progress Report: Greenhouse, small-plot field trials, and grower demonstration/validation trials showed that the Mi gene was stable in the sampled populations of root-knot nematode, and could contribute to management of root-knot nematode on tomato in northern Florida. C. Significant Accomplishments/Activities that Support Special Target Populations. None. 5. Describe the major accomplishments over the life of the project, including their predicted or actual impact. Large-scale field demonstration/validation trials of chemical alternatives to methyl bromide for soil disinfestation have been conducted for five consecutive years. Results demonstrated that near equivalent yields could be obtained using combinations of Telone, chloropicrin and several herbicides. However, the same broad range of pest suppression was not obtained using the alternatives over all years of testing. 6. What do you expect to accomplish, year by year, over the next 3 years? FY2004: Pest monitoring in the long-term alternatives to methyl bromide study will continue for an additional year. Naturally occurring mutants of weed biological control agents will continue to be sought. Studies will be continued on laboratory screening of pesticide compatibility with weed biological control agents. Greenhouse trials on the dodder biological control agent will be repeated. FY2005: Field trials will be performed with the dodder biological control agent and tests on the most disease-conducive environmental conditions will be continued. Studies on effectiveness of naturally occurring, more effective strains of biological control agents will be initiated. FY2006: Small-scale field trials on pesticide compatibility and optimization of formulation of biological control agents will be initiated. 7. What science and/or technologies have been transferred and to whom? When is the science and/or technology likely to become available to the end- user (industry, farmer, other scientists)? What are the constraints, if known, to the adoption and durability of the technology products? Six commercial scale of-farm field trials demonstrated to growers the performance of selected herbicides, alone and in combination, when used as part of an alternative program based on Telone C-35 broadcast application. Field days were conducted at multiple on-farm research sites. 8. List your most important publications in the popular press and presentations to organizations and articles written about your work. (NOTE: This does not replace your peer-reviewed publications listed below). Eger, J. E., Gilreath, J. P., Noling, J. W. Better Bed Wetting Through Science (Effect of irrigation times on wetting patterns in Florida vegetable soils). Proc. Florida Agricultural Conference and Trade Show. 2002. P. 40. Gilreath, J. P. The Search for Alternatives to Methyl Bromide in Vegetable Crops. University of Florida, Institute of Food and Agricultural Sciences, Experiment Station Report. 2002. Gilreath, J. P., Noling, J., Mirusso, J., Nance, J., Eger, J. Gilreath, P. R. Telone and Herbicides: Do's, Don'ts and Maybe's - a Primer for Tomorrow's Farmer. Proc. Florida Agricultural Conference and Trade Show. 2002. P. 37.

Impacts
(N/A)

Publications

  • Morales-Payan, J. P., Rosskopf, E. N., Yandoc, C. B., Semidey, N., Charudattan, R., Stall, W. M., DeValerio, J. T. Pathogens and their potential for biocontrol of nutsedges (Cyperus rotundus L. and C. esculentus L.): An overview with an emphasis on the fungus Dactylaria higginsii. Proceedings International Symposium on Biological Control of Weeds, Sonora, Mexico. 2002. p. 25-31.
  • Gilreath, J. P., Mirusso, J. M., Jones, J. P., Rosskopf, E. N., Noling, J. W., Gilreath, P. R. Efficacy of broadcast Telone C-35 in tomato. Proceedings Annual International Research Conference on Methyl Bromide Alternatives and Emissions Reductions. 2002. p. 19-1-2. MBAO.


Progress 10/01/01 to 09/30/02

Outputs
1. What major problem or issue is being resolved and how are you resolving it? Methyl bromide is a highly efficacious fumigant used on more than 100 crops to control insects, nematodes, weeds and pathogens. In Florida, it is considered essential for tomato and pepper production. Methyl bromide has been implicated as a major destroyer of stratospheric ozone and a complete phase-out of production and sale in the U.S. by the year 2005 is required. Chemical alternatives including combinations of 1,3 dichloropropene, chloropicrin, pebulate and napropamide have been identified as potential alternatives. Use of soil solarization in combination with resistant cultivars, organic amendments, biological control agents or the aforementioned chemicals has also been identified as a potential replacement to methyl bromide. None of the potential alternatives provide the same broad-spectrum level of control as methyl bromide across all cropping systems or environmental conditions. Additionally, the alternatives will require some modification in crop production practices by growers. To ensure that the performance of methyl bromide alternatives is evaluated under a diverse set of cropping systems and to provide growers with experience use of these alternatives, large-scale demonstration/validation studies were initiated in Fiscal Year 1996. The objectives of this CRIS are to: 1) evaluate the biological and economic implications of methyl bromide alternatives when applied by growers in large quantities under diverse cropping systems; 2) provide growers with opportunities to evaluate alternatives prior to the complete phase-out of methyl bromide. 2. How serious is the problem? Why does it matter? U.S. tomato, pepper and strawberry growers account for 39 percent of the domestic consumption of methyl bromide and 12 percent of the global consumption. In Florida alone, tomato and pepper growers account for 25 percent of the domestic production. Florida is the nations leading producer of fresh market tomato and pepper. During the 1997-98 crop, valued in excess of $745 million, methyl bromide was used to treat over 90 percent of the 59,200 acres planted. Without methyl bromide, production of tomato and pepper in Florida has been estimated to decline by 61.4 percent and 63.5 percent, respectively. This translates to nearly a $400 million loss in revenue for Florida producers alone. 3. How does it relate to the national Program(s) and National Program Component(s) to which it has been assigned? The development of alternatives to methyl bromide has been designated an area of high priority to Agricultural Research Service (ARS) and activities are coordinated under ARS National Program 308 - Methyl Bromide Alternatives. One of the objectives of National Program 308 is to develop multiple management strategies for soilborne pests. Pest management strategies are consistent with ARS Strategic Plans that call for development of agricultural systems that are highly competitive in the global market and protect natural resources and the environment. 4. What was your most significant accomplishment this past year? Continuous cropping over an extended period of time using promising alternatives to methyl bromide is required to determine if pest pressure will increase in comparison to plots treated with methyl bromide. For a fourth year at the University of Florida, Gulf Coast Research and Education Center, Bradenton, FL, fall applied Telone C-17 plus Tillam and soil solarization were compared to methyl bromide and an untreated control for management of soilborne disease, nematodes, and weeds in fall tomatoes followed by 3 spring cropping options: 1) double cropped cucumbers, 2) millet cover crop, and 3) fallow. Soilborne pest control and crop yields were similar to methyl bromide with Telone C-17 plus Tillam and intermediate between methyl bromide and the untreated control with solarization in fall tomato and spring cucumber, while millet germination and emergence was reduced following solarization. Results of this study provide evidence that repeated use of Telone C-17 plus Tillam over a period of years will not result in increased soil borne pest problems, thus removing one of the stumbling blocks to Telone C-17 use as a replacement for methyl bromide. B.Other Significant Accomplishment(s), if any: Acceptance of biological control as a viable weed control method requires incorporation into an integrated approach to crop production. Field trials were initiated to evaluate Dactylaria higginsii for control of nutsedge in an off-season weed management program and in a crop production setting combined with 1,3-dichloropropene and compared to 1,3- dichloropropene and pebulate. There was no statistical difference in tomato yield attributable to fallow season treatments and overall tomato yield from fumigant/fungus-treated plots was statistically equivalent to yields achieved in the fumigant/herbicide-treated plots. Completion of the multi-year study will determine if Dactylaria higginsii can be used for nutsedge control in an IPM approach in vegetable production. Additional work is necessary on the production of inoculum of Dactylaria higginsii for use in large-scale experiments and field validation studies. Carbon and nitrogen sources were evaluated for enhancement of growth of the fungus. The highest amount of mycelial growth was produced in the medium containing sucrose as the carbon source and no significant difference in mycelial growth was observed with different nitrogen sources. Results of this study will enhance efforts to produce seed cultures for large-scale inoculum production of the biological control fungus. Florida tomato growers have limited experience with application of preplant incorporated herbicides and use of Telone C-35 as an alternative to methyl bromide, therefore a project was conducted to demonstrate to them the proper selection and application of herbicides in combination with broadcast application of Telone C-35 and familiarize them with the nuances of herbicide application in large plots on their farms. Large plot (2 to 10 acre) field trials were conducted at 5 farms in the Palmetto - Ruskin production area and one farm near Immokalee, FL during the spring and fall of 2001 and all utilized labeled, preplant, soil incorporated herbicides in combination with Telone C-35 applied broadcast. In general, soilborne pest control was similar to methyl bromide with these alternatives, with the exception of one trial where the grower used his own equipment to apply and incorporate herbicide and had poor nutsedge control due to too shallow incorporation, demonstrating the need for proper equipment and strict attention to details related to herbicide application. Grower recognition of the importance of proper herbicide application and incorporation techniques is the most important aspect of this project and the problems encountered in the one grower trial do more to educate the grower and neighboring farmers than any properly conducted demonstration ever could. C. Significant Accomplishments/Activities that Support Special Target Populations. None. 5. Describe your major accomplishments over the life of the project, including their predicted or actual impact? Large scale field demonstration/validation trials of chemical alternatives to methyl bromide for soil disinfestation have been conducted for four consecutive years. Results demonstrated that near equivalent yields can be obtained using combinations of Telone, chloropicrin and several herbicides. However, the same broad range of pest suppression was not obtained using the alternatives. 6. What do you expect to accomplish, year by year, over the next 3 years? The current Specific Cooperative Agreement under which this research is funded expired on 31 July, 2001. The cooperative agreement was No. 58- 6617-6-013 and is titled "Field scale demonstration/validation studies of alternatives for methyl bromide in plastic mulch. Unobligated funds were moved to 7 new SCAs. Reports for the majority of these agreements are not due until 8/31/2002. 7. What technologies have been transferred and to whom? When is the technology likely to become available to the end user (industry, farmer other scientist)? What are the constraints, if known, to the adoption durability of the technology? Six commercial scale trials demonstrated to growers the performance of selected herbicides, alone and in combination, when used as part of an alternative program based on Telone C-35. Field days were conducted at 2 of the on-farm research sites. 8. List your most important publications and presentations, and articles written about your work (NOTE: this does not replace your review publications which are listed below) Gilreath, J., Noling, J., Mirusso, J., Nance, J., Eger, J., Gilreath, P. Telone and herbicides: Do's Don'ts and Maybe's-a primer for tomorrow's farmer. Proceedings of Florida Ag. Conference and Trade Show. Lamb, E.M. , McAvoy, G., Olczyk, T. eds. University of Florida, Institute of Agricultural Sciences, Gainesville, FL. 2001. pp. 37-40. Gilreath, James P. Methyl Bromide Alternatives and Their Current Limitations in Florida, USDA - ARS Methyl Bromide Alternatives Newsletter and presentation at USDA - ARS and US EPA sponsored Methyl Bromide Alternatives meeting. 2001. Princess Anne, MD. Gilreath, James P. The Search for Alternatives to Methyl Bromide in Vegetable Crops. University of Florida, Institute of Food and Agricultural Sciences, Experiment Station Report. 2002.

Impacts
(N/A)

Publications

  • Gilreath, J.P., Noling, J.W., Jones, J.P., Locascio, S.J., Chellemi, D.O. Three years of soilborne pest control in tomato with 1,3-D plus chloropicrin and solarization. Proceedings of Annual International Research Conference Methyl Bromide Alternatives and Emissions Reductions. 2001. v. 13. p. 1-3.