Progress 10/01/05 to 09/30/06
Outputs
Progress Report 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? Why does it matter? This project is aligned with NP308 Alternatives to Methyl Bromide. Methyl bromide is the most commonly used management strategy to control soilborne diseases, nematodes, and weeds in high value fruits, nuts, vegetables, nursery crops, and ornamentals. Availability of methyl bromide was restricted in January 2001 to 50% of the amount used in the baseline year of 1991 and was further restricted to 30% of the baseline in 2003. It was completely banned in 2005 except for uses with approved Critical Use Exemptions (CUE) or Quarantine/Preshipment (QPS) uses. CUEs are granted on a one-year basis. Strawberry, orchard and vineyard replant, ornamentals, and perennial nurseries have received Critical Use Exemptions for 2005 and 2006. U.S. growers of these high value crops are in dire need of
alternatives to the use of methyl bromide. The methyl bromide phase-out will result in an estimated 50% yield reduction in some crops and large economic losses, especially in strawberry, ornamental, and nursery crops, if effective alternatives are not found and CUEs are not granted. The availability, or lack of acceptable alternatives will in turn, impact the supply and quality of these commodities to American consumers and the export market. Pre-plant soil fumigation with methyl bromide is used to control "replant disorder", meet regulatory requirements for clean propagative material, and control weeds and soilborne pathogens for many high value crops including grapes, stone fruit and nut trees, strawberries, nursery crops, and ornamentals. The phase out of methyl bromide highlights two major challenges. The first is to quickly find effective control measures that are economically feasible, fit current cropping systems, and are acceptable to environmental and regulatory agencies.
We are approaching this challenge by testing unregistered chemicals, novel applications of currently available chemicals, and new application technologies to deliver effective concentrations of materials to the target pests. Our team expertise in crop production, plant pathology, nematology, irrigation management, and soil chemistry, provides us the tools to address the biological, chemical, and engineering aspects of this project. Our current results indicate that this approach will meet the short-term to mid-term need. The second challenge is to increase our understanding of the pathogens and soil factors limiting crop production. A successful, long-term, integrated management approach requires a thorough understanding of biological, chemical, and physical soil factors, their interactions, and their spatial variability, and will include cultural, genetic, biological and chemical management strategies. Greenhouse, microplot, and field studies will generate new knowledge of these
interactions and their responses to currently available and newly developed management strategies. Innovative adaptations of drip irrigation technologies to develop a delivery system for biological and chemical management options offer the potential for greater flexibility and increased responsiveness to spatial variability. A better understanding of the causes of poor plant vigor in high value annual and perennial crops will lead to more science-based selections of management strategies. Effective, economic, environmentally acceptable pest and pathogen management strategies will contribute to the on-going productivity of high value annual and perennial cropping systems and the continued availability of clean planting stock from certified nurseries. The ultimate result will be a safe, dependable, high quality, and affordable food and flower supply for domestic and foreign markets, on- going productivity of crop production systems (many of them family farms), and protection of the
environment. Some of the knowledge gained may be specific to a particular crop production system or to California conditions, however, general principles regarding pathogen and pest management, technology and application methods, economics of alternative systems, irrigation and nutrient management, and precautions for providing environmental protection will be transferable to other crops and areas. Anticipated products from this project include new knowledge of, and diagnostic methodologies for, determining the causes of poor plant vigor in strawberry, ornamental, perennial, and nursery production systems in the absence of methyl bromide fumigation; new pest and pathogen management strategies that utilize new knowledge and novel application methods to effectively and economically control pests and pathogens while protecting the environment; field scale demonstrations of alternative management strategies, conducted in partnership with growers; growers who continue to be competitive in
the world market; and safe, dependable, high quality, affordable food and flower supplies. This work is relevant to producers of high value crops who currently use methyl bromide, Cooperative Extension personnel, pest control advisors, crop consultants, and scientists interested in the complex interactions between biological, physical, and chemical soil factors and their impact on crop growth, yield, and quality. The potential impact of this work is to substantially change soilborne pest and pathogen management for high value crops to strategies that are practical, economically feasible, and environmentally acceptable. 2. List by year the currently approved milestones (indicators of research progress) Year 1 (FY2006) Pathogen Isolation 101. Pathogens from diseased materials isolated from the various ornamental field trials. Pathogenicity 102. Organisms isolated from ornamental fields tested for pathogenicity on various hosts according to Koch's postulates. Management Strategies 103.
Rate studies conducted of various methyl bromide alternatives for cut flower production. 104. Dose-rate response experiments will be conducted in the lab with various emerging chemicals on pathogens, nematodes, and weeds important in ornamental cropping systems. 105. Field efficacy/phytotoxicity evaluations of 2-bromo ethanol (Agent 2B) completed. 106. Perennial crop yield and nematode control 3-5 years after treatment (alternative fumigants, fallow and resistant rootstocks) evaluated in vineyard replant trials. 107. Long term trials to evaluate perennial crop yield and nematode control under vineyard replant conditions 6-8 years after treatment completed, unless results indicate that maintaining trials an additional year would be of great benefit. 108. Microplot studies initiated to evaluate of potential alternatives to methyl bromide for perennial and nursery cropping systems. 109. Microplot trial initiated to evaluate post-plant nematicides in perennial cropping systems. 110. Data
and economic analysis completed for 5 orchard replant field trials and manuscripts written and submitted. 111. Two field trials on orchard and/or nursery crops established to compare drip and shank application of 1,3-D and chloropicrin under field conditions. Application Technologies and Emission Reduction 112. Column experiments conducted to evaluate effect of surface water seals, alone and in combination with plastic tarps, on reducing fumigant emissions from different types of soils. 113. Emission reduction studies expanded to other potential fumigants such as iodomethane. 114. Soil surface sealing techniques and other management practices that reduce fumigant emissions of toxics and volatile organic compounds in field trials evaluated. 115. Field trials conducted in different soil types and at different seasons, in combination with tarps, to study fumigant distribution in soils and emissions with drip and shank applications. 116. Field tests and computer modeling carried out to
optimize water/fumigant application practices for drip fumigation. Field Trials and Commercial Demonstrations 117. Establish new cut flower trials with new and emerging products. 118. Almond and walnut nursery trials in commercial fields completed. 119. Initiate new 2-year field nursery crop trial in commercial fields, if field with adequate pest pressure is available. 120. Orchard replant trials in commercial fields initiated in FY04 on- going (Madera trials). 121. Complete evaluation of 2 alternative fumigant orchard replant field trials (Enns trials). 122. Two field trials with orchard crops established to compare drip and shank application of 1,3-D and chloropicrin under field conditions. 123. Two field trials of no-till strawberries carried out. Year 2 (FY2007) Pathogen Isolation 201. Pathogens from diseased materials isolated from the various ornamental field trials. Pathogenicity 202. Organisms isolated from ornamental fields tested for pathogenicity on various hosts
according to Koch's postulates. Management Strategies 203. Rate studies conducted of various methyl bromide alternatives for cut flower production. 204. Initiate field efficacy/phytotoxicity of herbicides used with 1,3-D soil fumigation for weed control in almond tree nursery production. 205. Initiate field efficacy/ phytoxicity evaluations of post-plant herbicides in field grown ornamentals. 206. Perennial crop yield and nematode control 4-6 years after treatment evaluated in vineyard replant trials. 207. Microplot trial to evaluate post-plant nematicides for perennial production systems initiated. Application Technologies and Emissions Reductions 208. Column experiments conducted to evaluate effect of surface water seals on fumigant emission reductions from different types of soils. 209. Tests conducted on various surface sealing techniques including water seal, chemical seal, organic matter cover, and plastic tarps to reduce fumigant emissions from soil columns and define
potential methods that can be tested in field trials. 210. Soil column experiments conducted to determine potential of chemical amendments in reducing fumigant concentrations under VIF tarp after achieving fumigation efficacy to minimize workers' exposure risks when planting. 211. Small-plot field trial conducted to determine effective surface seal methods to reduce fumigant emissions under shank-broadcast fumigation. Field Trials and Commercial Demonstrations 212. Additional cut flower trials established with new and emerging products. 213. 2-year nursery crop trial that was initiated in commercial rose field nurseries in FY06 continued. 214. Orchard replant trials in commercial fields initiated in FY04 completed (Madera). 215. On-going evaluations conducted for orchard replant trials (Thiessen) in commercial fields initiated in FY06. 216. Large field trial conducted to test several commercial plastic films on fumigant emission reductions in strawberry fields (raised beds).
Year 3 (FY2008) Pathogen Isolation 301. Pathogens will be isolated from floricultural crops not studied before. Pathogenicity 302. Isolated pathogens will be tested according to Koch's postulates. Management Strategies 303. Rate studies conducted of various methyl bromide alternatives for cut flower production. 304. Almond nursery herbicide trials completed. 305. Initiate microplot and greenhouse experiments to evaluate biofumigation techniques for control of weeds common in floriculture and perennial nursery fields. Application Technologies and Emissions Reductions 306. Studies conducted to verify fumigation efficacy under effective emission reduction surface seal methods. Field Trials and Commercial Demonstrations 307. Field trials will be conducted in floriculture cropping systems not studied before using standard as well as emerging chemicals. 308. 2-year nursery crop trial that was initiated in FY06 in commercial field nurseries completed. 309. On-going evaluations
carried out for orchard replant trials in commercial fields initiated in FY06. 310. Large field trial conducted to verify effective plastic tarps to reduce fumigant emissions in strawberry fields (raised beds). 311. Field trial will be conducted in commercial nursery to test reduced MB rates under standard HDPE and VIF mulch (Visalia). Year 4 (FY2009) Pathogen Isolation 401. Pathogens will be isolated from floricultural crops not studied before. Pathogenicity 402. Isolated pathogens will be tested according to Koch's postulates. Management Strategies 403. Rate studies conducted of various methyl bromide alternatives for cut flower production. 404. Initiate field trials to determine effects of irrigation techniques on weed management in field nurseries. Application Technologies and Emissions Reductions 405. Additional data required to register management practices that reduce fumigant emissions is collected and summarized. 406. Model developed and tested that can predict the
effect of management practices on fumigant emissions for various soil types and climatic conditions. 407. Information and research findings submitted to regulatory agencies (e.g., Cal DPR) for developing guidelines on field practices that can effectively reduce emissions and be adopted by growers. Field Trials and Commercial Demonstrations 408. Field trials will be conducted in floriculture cropping systems not studied before using standard as well as emerging chemicals. 409. Large field trial conducted to test effective and economic management and surface seal methods including water seal and plastic tarp in combination with other conditions (soil types and weather) to minimize fumigant emissions. 410. Field trials will be conducted in commercial tree nurseries to test efficacy of standard and emerging chemicals under new tarping systems. 4a List the single most significant research accomplishment during FY 2006. All accomplishments are linked to Component I of the Action Plan for
National Research Program 308 Alternatives to Methyl Bromide. Drip application of fumigants in fine textured soils. Field trials conducted by ARS, Water Management Research Unit, Parlier, California in commercial certified nurseries for tree crops demonstrated that drip application technologies that are comparable to standard shank-injection in coarse textured soils (sandy loams) are not as effective at controlling plant parasitic nematodes as shank-injection in fine textured soils (loam and clay loam). Growers of certified propagative material for orchards and vineyards must be able to produce crops that are free of plant parasitic nematodes at the end of one and two year crops. Distribution of some fumigants is not adequate following shank-injection in fine-textured soils and drip fumigation is suggested as a possible solution to obtain better distribution of fumigants in fine textured soils. Iodomethane + chloropicrin (pic), 1,3-dichloropropene (1,3-D) alone, and 1,3-D + Pic
were applied by standard shank-injection methods and as emulsified formulations through drip irrigation systems and compared to standard methyl bromide fumigation for nematode control in sandy loam, loam, and clay loam soils. Although nematodes at the 15 and 30 cm depths were killed by drip fumigation, nematodes at the 60 and 90 cm depths survived. Drip fumigation was shown to be inadequate for nematode control for certified nurseries grown on fine textured soils. (National Program Component: Preplant Soil Fumigation Alternatives. Problem Statement: The need to increase our understanding of the pathogens and soil factors limiting crop production.) 4b List other significant research accomplishment(s), if any. Water seal to reduce fumigant emissions. Two field trials in small plots were conducted by ARS, Water Management Research Unit, Parlier, California on a sandy loam soil and both showed that water seal (spraying water to soil surface following shank fumigation) can reduce
Telone as well as chloropicrin emissions more effectively than standard HDPE tarp and cost substantially less (HDPE tarp: $800/ac; water seal: <$300/ac). Fumigation acreage in California alone is >50,000 acres each year. Thus, water seal can reduce fumigation cost effectively. (National Program Component: Preplant Soil Fumigation Alternatives. Problem Statement: To find effective control mesures that are economically feasible, fit current cropping systems, and are acceptable to environmental and regulatory agencies.) Drip fumigation with water cap reduces emissions. A field trial conducted by the ARS, Water Management Research Unit, Parlier, California in November 2005, in a field adjacent to our location indicates that drip fumigation (chemigation) followed by water cap (sprinkling water over soil surface following fumigation) resulted in much lower emissions of 1, 3-dichloropropine, chloropicrin and iodomethane than drip fumigant with HDPE tarp. Plastic tarps are too expensive
for most orchard replanting and vegetable growers. When water and sprinklers are available, drip fumigation in combination with micro-sprinklers appears practical to achieve fumigation purpose while reducing emissions. These findings will most likely affect regulatory development on fumigation use and be adopted by growers. (National Program Component: Preplant Soil Fumigation Alternatives. Problem Statement: To increase our understanding of the pathogens and soil factors limiting crop production.) 4c List significant activities that support special target populations. Presentation on Strawberry Irrigation at Oxnard Strawberry Workshop was translated into Spanish. The UCCE Strawberry Fumigation workshop was presented twice in Spanish. 4d Progress report. Pythium root rot control: Pythium root rot is a significant problem in the production of calla lily rhizomes for the potted flowering plant market. Two trials were established to evaluate control of Pythium root rot on calla
lily by use of pre-plant soil fumigants followed by the application of low molecular weight control agents through the irrigation system following crop establishment. This work will be completed in the fall of 2006. Initial results indicate that significant control is achieved with the pre-plant treatments, but the effect of the post plant treatments is still to be determined. Use of soft chemical as replacements for pre-plant methyl bromide fumigation. Two trials were established to test "soft" alternatives to methyl bromide. Theses treatments included 2-bromoethanol, dimethyl disulfide, sodium azide, furfural, and propylene oxide. Two trials were established in Goleta, CA and planted with various cut flower crops. These trials will be completed in the fall of 2006. Perennial field nursery and orchard replant trials. Two nut tree nurseries were completed and one nut tree nursery and two nut orchard replant trials are on-going in commercial fields as part of a large team project
including ARS and University of California. Bags containing weed seed were buried at 3 inch soil depth and bags containing fungal pathogens and plant parasitic nematodes were buried at 6, 12, 24, and 36 inch soil depths prior to fumigation. Control of these pests and pathogens by tarped, shank-injected 1,3-D (Telone II), iodomethane + chloropicrin (Midas), and 1,3-D + chloropicrin (Telone C35) was comparable to methyl bromide at all depths in coarse-textured soils, but control of fungi and nematodes was not as good as methyl bromide at the deeper soil depths in finer-textured soils. Native soil and root nematode populations at harvest were sporadic, even in the untreated control. Recruited and hired a new weed scientist who came on-board in November 2005. The work since joining the team include three preliminary nut tree nursery and two garden rose nursery herbicide screening trials located in commercial nursery fields that are ongoing to identify potential herbicide products and
application techniques to maximize weed control and crop safety. The preliminary trials will be evaluated through the current growing season and into the second year of production. The data will be used to develop further research into the most promising products and techniques for weed control. New herbicide trials will be initiated in FY2008. 5. Describe the major accomplishments to date and their predicted or actual impact. All accomplishments are linked to Component I of the Action Plan for National Research Program 308 Alternatives to Methyl Bromide. Problem Area: Effective, economic, environmentally acceptable pest and pathogen management strategies that will contribute to the on-going productivity of high value annual and perennial cropping systems and the continued availability of clean planting stock from certified nurseries. Fumigant field trials for cut flower production. Pathogenicity tests determined the organisms causing disease in floriculture crops include
Pythium sp. on calla lily, Cylindrocladium on myrtle, and Fusarium oxysporum on freesia. Field trials were conducted to evaluate alternative chemicals (iodomethane + chloropicrin (Midas), 1,3-D + chloropicrin (InLine), and furfural) for pathogen and weed control in freesia, stock, snapdragon, iris, Gypsophila and calla lily production systems. Treatments containing chloropicrin (Midas and InLine), applied with drip-fumigation technologies, resulted in per acre yields comparable to those the grower obtained with the standard methyl bromide + chloropicrin fumigation. Furfural alone had little or no weed or pathogen control activity and is not a technically feasible alternative to methyl bromide for weed or pathogen control in cut flower production systems. Alternative chemicals were shown, in some cases, to be useful as methyl bromide alternatives. As a result of this research, bulb growers have started using drip irrigation technology to apply methyl bromide alternatives to their
production fields resulting in a cost savings by eliminating in-season fungicide applications. The research is being used by growers, the California Cut Flower Commission, and U.S. EPA. This research was used to support the U.S. EPA Critical Use Nomination for ornamental crops and contributed to the granting of a Critical Use Exemption for cut flower growers for 2005 and 2006. Grapevine Nursery Trial. Three drip-applied fumigants were evaluated as methyl bromide alternatives for 1-year field-grown nursery cropping systems at the San Joaquin Valley Agricultural Sciences Center. Sodium azide, 1,3-dichloropropene (1,3-D) + chloropicrin (Pic), and iodomethane (IM) + Pic were applied to a rootknot nematode infested field prior to planting grape nursery "sticks". When plants were harvested at the end of the one year cropping cycle, root galls (which make the vines unmarketable) were found on 92% of the Thompson Seedless and 100% of the Cabernet Sauvignon plants in untreated plots, 67%
of the Cabernet Sauvignon and 54% of Thompson Seedless in azide treated plots, and were absent in the methyl bromide, 1,3-D + Pic, and IM + Pic treated plots. These results suggest that 1,3-D+Pic and IM+Pic are good candidates as alternatives to methyl bromide on the California Department of Food and Agriculture (CDFA) "approved Certified Nursery soil treatment list" for sandy loam soils. This research is used by certified nursery growers, CDFA, and U.S. Environmental Protection Agency. Methyl bromide alternatives for 2-year field nursery crops. Tree and rose nurseries (propagative materials), grown in the open field for one to two years, commonly use methyl bromide as a preplant soil fumigant to control soilborne pathogens, pests, and weeds and to comply with California regulations governing certified nurseries. Alternative fumigants were applied by shank injection (tarped and untarped) and through drip irrigation in trials located at commercial tree and rose nurseries.
1,3-dichloropropene + chloropicrin and iodomethane +chloropicrin provided control, in sandy loam soils, of plant parasitic nematodes similar to methyl bromide down to a soil depth of five feet (150 cm) at the time of planting, resulted in soil nematode populations similar to methyl bromide after one growing season, and when tarped, resulted in the harvest of nematode-free two-year crops (as required by the clean propagative material regulations) that were similar in quality to crops grown in methyl bromide treated soil. This research was used to support the U.S. EPA Critical Use Nomination for nursery cropping systems and contributed to the granting of a critical use exemption for 2005, 2006 and 2007. Customers include nursery growers, U.S. EPA, and fumigation companies. Replant Disorder Field Trial. Perennial crops are not treated every cropping season, as are annual crops, but only when the orchard or vineyard is replanted. Stonefruit, nut tree and vine growers face significant
challenges to control soil pests and reduce the effects of the "replant disorder" when replacing existing orchards and vineyards. Several alternatives were tested in replanted peach, plum, and almond orchards and vineyards in a series of field trials located at the San Joaquin Valley Agricultural Sciences Center and in growers' fields in Dinuba and Madera, CA. Emulsified formulations of alternative fumigants 1, 3 dichloropropene (1,3-D) and chloropicrin applied through subsurface drip irrigation systems produced tree growth and yield equal to methyl bromide. InLine (1,3-D + chloropicrin) provided nearly equal benefits in growth and yield when replanting fruit tree orchards where replant disorder was a problem but there were no acute pathogens or nematodes. 1, 3-D and chloropicrin resulted in increased early growth and vigour and about 20% increase in yield over years 3 - 6. The yield impact declines with tree maturity. Economic analysis showed that 1,3-D fumigation is economically
beneficial, while more expensive methyl bromide fumigation provides marginal returns under the above conditions. Control of plant parasitic nematodes in vineyard replant plots following treatment with 1, 3-D + chloropicrin, iodomethane + chloropicrin, or propargyl bromide was comparable to control achieved by methyl bromide for up to 6 growing seasons after treatment irrespective of whether conventional shank- injection or drip-fumigation application technologies were used. Shank- injection and drip application of currently registered and unregistered materials can provide growers with alternative soil treatments in sandy loam soils that provide control similar to that achieved with methyl bromide. This research was used to support the U.S. EPA Critical Use Nomination for perennial replant situations and contributed to the granting of a Critical Use Exemption for 2005, 2006 and 2007. Efficacy of fallow as an alternative to methyl bromide for perennial replant. The benefit of one,
two, and three years of dry fallow as an alternative to methyl bromide for perennial replant disorder was quantified for peaches, plums, and grapes. After five years of growth, and two or three years of fruit production, one year of fallow increased yields in all stonefruit trials by 10 to 20%. In peaches and plum replant trials where acute pathogens and nematodes were not present, each additional year of fallow increased growth and yield, with three years of fallow giving similar yields to that produced with methyl bromide fumigation. In the grape trial, after 5 years of growth, there was no significant difference in yield for any treatment (untreated, methyl bromide, or 1-3 year fallow) for all three scion/rootstock combinations tested. Vines grown in untreated plots and plots following a 1 year fallow had significantly smaller trunk diameters than vines grown in methyl bromide treated plots for two of the three scion/rootstock combinations tested. The beneficial impact of the
increasing length of the fallow period was detectable in citrus nematode populations (Tylenchulus semipenetrans) only for the first growing season and only in the upper soil layers, while rootknot nematode populations (Meloidogyne spp.) differed as a function of the length of the fallow for three growing seasons. Nematode populations of both genera remained significantly lower in methyl bromide fumigated plots after four growing season than in all fallow treatments. Economic analysis indicated that the costs associated with 3 years of fallow were less expensive than methyl bromide fumigation, but more expensive than Telone fumigation. Fallowing presents a treatment alternative for growers that face replant disease but prefer not to fumigate. Alternatively, fallowing can be combined with other methyl bromide alternatives, such as a nematicide or resistant rootstock, for a more robust MB alternative than fallow alone. Users of this research are grape growers and crop consultants.
Drip-application technologies for pre-plant fumigants. Over 80% of the commercial strawberries in the US are grown in California. This $1 billion industry has relied on methyl bromide soil fumigation to prepare their fields. California strawberry growers have received a Critical Use Exemption for more than 2 million pounds of methyl bromide for use in 2007. Through 5 years of field research trials in collaboration with manufacturers, applicators, and growers, the San Joaquin Valley Agricultural Sciences Center Methyl Bromide Research Team has demonstrated that drip fumigation is effective and has developed management practices to maximize efficacy. In 2001, manufacturers and applicators received registration from EPA to apply two alternative fumigants, 1,3-Dichloropropene (Telone) and chloropicrin, by drip fumigation. Through 6 years of trials on commercial strawberry fields, including 23 field demonstration trials, we developed application equipment and procedures, and
demonstrated the technology to growers. In its first year of registration, InLine, a combination of these two fumigants formulated for drip application, was applied to 900 acres of strawberries. In 2003, this product and an emulsified chloropicrin (TriChlor EC) were applied to 5000 acres, over 15% of the strawberry crop with a potential value of $150 million. In 2004, the California Strawberry Commission reported that 35% of the 33,000 acres of strawberries were using alternatives to methyl bromide, the majority of these were drip-applied using technologies developed by ARS. Drip fumigation is also being used on melons and peppers, crops that are cultivated on plastic-mulched, drip-irrigated beds similar to strawberries. Growers like this application method because it is inexpensive and reduces worker risk. It may also reduce fumigant emissions and risks to neighbors. Our drip-application technology has also been tested and demonstrated under commercial conditions in two
orchards, three nut tree nursery fields and one rose nursery field in addition to numerous research plots located on the California coast and in the San Joaquin Valley. This research was used to support the U.S. EPA Critical Use Nomination for strawberry cropping systems and contributed to the granting of a Critical Use Exemption for 2005 and 2006. Soil water model for improved drip fumigation. Effective drip application of fumigants depends upon delivering the fumigants to the target soil zone. Computer models are useful to evaluate management practices to enable precision placement of the water and fumigants. Field data was collected to validate a two-dimensional soil water flow model for conditions of drip irrigation in collaboration with ARS- Riverside. Hydrus 2-D was able to model the collected data very well using only soil particle size data to determine hydraulic parameters. Follow-up field research and model simulations indicated that water application practices such as
fast application rate or pulsed (intermittent) application does not improve water distribution. This information shows that the water movement process is controlled mainly by soil texture and there is little applicators can do to improve horizontal movement of fumigants. Customers for this research include fumigation companies and growers. Efficacy of propargyl bromide. A multi-agency (USDA and university) and multi-state (CA and FL) effort to determine the efficacy of propargyl bromide as a soil fumigant was carried out by USDA-ARS, Univ. CA, California Strawberry Commission, Univ. of Florida, and USDA IR-4 Methyl Bromide Alternatives Program, with USDA funding. The studies on tomato, strawberry, carrot, fruit trees, grape vines, and ornamentals determined that propargyl bromide is efficacious against most pests including nematodes, diseases, and weeds at rates above 100 pounds per acre, which is about 1/3 the current methyl bromide use rate, and generally resulted in good plant
growth and yield, although some phytotoxicity was noted in two trials. These coordinated studies indicate that propargyl bromide can be an efficacious replacement for methyl bromide. Unfortunately, there is currently no private sector interest in pursuing registration of this material. Fumigation efficacy and emission reduction. Prior to 2004, our research had been focusing on alternative fumigants that can replace methyl bromide and application methods to effectively deliver fumigants to soil target volumes to maximize fumigation efficacy. In the last few years, emission-reduction has become critical in registration and maintaining the availability of soil fumigants to growers because of high emissions and subsequent stringent regulations. Since 2004, our group expanded research to developing practical management methods to reduce emissions while achieving fumigation efficacy. Laboratory column experiments and field plot tests have been conducted by the group scientists including
pathologist, agricultural engineer, and soil scientist to examine emission reduction and fumigation efficacy under various surface seal and application methods. We have been focusing on water seal practices that demonstrated high potential in reducing emissions and also cost less than standard tarp or conditions. Our research data have shown that water seal can reduce emissions of Telone products effectively more than standard plastic tarp. Continuing research is essential before mature technology can be developed and transferred. Irrigation Distribution Uniformity in Commercial Fields. Effective and efficient drip application of fumigants depends on uniform distribution of the fumigants and water through the drip irrigation system. Irrigation distribution uniformity was measured on 39 strawberry fields throughout the strawberry growing regions of California. Distribution uniformity varied from 45% to 93% and averaged 81% (a value that is disappointingly low for a precision system
that can achieve over 90% uniformity) which results in a need for one-quarter additional water (or drip applied fumigant) to achieve the target amount on the drier areas of the field. This work identified problems related to improper design (beds too long), equipment (connector spaghetti tubing too small), and management (non-uniformly set valves). These results and recommendations were presented to strawberry growers in 6 irrigation workshops and will result in improvements in strawberry irrigation and drip fumigation. Customers include growers and fumigation companies. Evaluation of Impact of Township Caps on Availability of 1,3- dicholoropropene. Use of 1,3-dichloropropene (Telone) in California is limited by state "township cap" regulations. California pesticide use databases maintained by the state were analyzed to determine fumigant use trends and the likely impact of township caps on adoption of fumigants that contain this chemical as alternatives to methyl bromide. The
analysis showed severe impacts on certain commodities and geographic areas. These data are being used extensively by US EPA and Parties to the Montreal Protocol to evaluate Critical Use Exemption nominations for continued methyl bromide use for those circumstances where 1,3-D would be the only viable alternative, but is not expected to be available due to township caps. Strawberry Fumigation Training Manual. Substantial research evaluating and testing methyl bromide alternatives for strawberries has been completed and demonstrated, but over half of strawberry growers continue to use methyl bromide and Critical Use Exemptions continue to be requested. A training manual for use of methyl bromide alternatives in strawberries was written by San Joaquin Valley Agricultural Sciences Center Methyl Bromide Research Team in cooperation with the CA Strawberry Commission (CSC) and Univ. of Calif. Cooperative Extension (UCCE). A series of 4 workshops on adoption of alternatives was conducted
by UCCE and CSC using the Manual, and a chapter on drip fumigation methods was written for the UC Strawberry IPM Manual. With the aid of these training materials, adoption of alternatives in CA strawberries is growing at over 20% per year. No-till strawberry production. Strawberry growers consume time, energy, water, and money preparing a strawberry field for the following year's strawberry planting. With drip fumigation, these costs could be reduced by reusing the previous strawberry beds. A no-till study of strawberry was initiated by the San Joaquin Valley Agricultural Sciences Center Methyl Bromide Research Team in 2001 in which strawberries are replanted on the same planting beds in consecutive years following removal of the previous plants, replacement of the drip tape and tarp, and drip fumigation. This process reduces production costs by over $600 per acre, reduces water use, and reduces plant-back time (and thus extends harvest time of the previous crop) by 2 to 3 weeks.
Results from the two-year field trial completed at Salinas showed no yield loss with bed reuse and current year yields show no yield decline for third year use of the same beds. Customers for this research include strawberry growers and crop consultants. 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? Knowledge and information on using surface water seals to reduce fumigant emissions were presented to California almond growers and stakeholders at the 33rd Almond Industry Conf., Modesto, CA, Dec. 7-8, 2005 (Attendance: >100). The information is also included in conference proceedings that were distributed to attendees. Oral presentations on developing field practices to improve fumigation efficacy while reducing emissions were given to Fruit tree,
Nut tree, and Grapevine Improvement Advisory Board (IAB) (growers and stakeholder) on April 28, 2006. The information was well received and support for research was approved by this board. Efficacy of alternative fumigants and drip fumigation technologies for ornamental cropping systems were presented at grower meetings. A field day with growers was conducted this summer showing the technology being used in the field. As a result of the transfer of our research results, calla lily rhizome growers are now using drip-applied soil fumigants on a portion of their crop. Consulted with the CA Strawberry Commission on fumigation guidelines for growers and applicators to minimize risk of fumigant spills and emissions incidents (in response to two incidents in 2005) Knowledge on methyl bromide alternatives for field nurseries was transferred to growers, fumigation companies, and research colleagues at numerous commodity group and research meetings. 7. List your most important publications in
the popular press and presentations to organizations and articles written about your work. (NOTE: List your peer reviewed publications below). Presentations Gao, S., and T. Trout. Develop management practices using surface water seals and tarps to reduce fumigation emissions. Progress Report to California Department of Food and Agriculture, February 6, 2006. 6 p. Gao, S., and T. Trout. Develop management practices using surface water seals and tarps to reduce fumigation emissions. Second Progress Report to California Department of Food and Agriculture, May 31, 2006. 8 p. Hanson, B. Alternatives to Methyl Bromide for Weed Control in Tree Nurseries. California Association of Nurseries and Garden Centers (CANGC) Deciduous Grower Committee Meeting. Hickman, CA. June 2006. Schneider, S. Methyl bromide alternatives for nut tree nurseries - field trial results California Association of Nurseries. Yuba City, CA. Oct. 2005. Schneider,S. and B. Hanson. Evaluation of Alternatives to Methyl
Bromide for Roses. Garden Rose Council. Davis, CA. June 2006. Schneider, S. and R. Keigwin. Alternatives to Pre-plant Use of Methyl Bromide Research, Regulatory Issues, and Critical Use Exemptions. Methyl bromide alternatives update meeting for Michigan growers. Grand Rapids, MI. Feb. 2006 Trout, T. Strawberry Irrigation Scheduling. UCCE Strawberry Workshop, Oxnard. Sept, 2005. Trout, T. Update on the Methyl Bromide Phaseout. California Minor Crops Tour. July, 2005. Popular Press Articles written about us Finding a Good Replacement. American Vegetable Grower, Aug 2005.
Impacts
(N/A)
Publications
- Gerik, J.S. 2005. Drip applied soil fumigation for freesia production.. Hortechnology. Oct-Dec. 2005 15 (4) pgs 820-824.
- Gerik, J.S., Greene, I.D., Beckman, P., Elmore, C.L. 2006. Pre-plant drip applied fumigation for calla lily rhizome nursery. HortTechnology. Vol 16, pgs 297-300.
- Williams, L.E., Trout, T.J. 2005. Relationships Among Vine- and Soil-based Measures of Water Status in a Thompson Seedless Vineyard in Response to High-Frequency Drip Irrigation. American Journal of Enology and Viticulture. Vol 56:4 (2005) pp 347-366.
- Stromberger, M.E., Klose, S., Ajwa, H.A., Trout, T.J. 2005. Microbial Populations and Enzyme Activities in Soils fumigated with Methyl Bromide Alternatives. Soil Science Society of America Journal, 2005, Vol 69: 1987- 1999.
- Chow, A.T., Gao, S., Dahlgren, R.A. 2005. Physical and chemical fractionation of dissolved organic matter and trihalomethane precursors: A Review. Journal of Water Supply: Research and Technology (AQUA) 54:475- 507.
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Progress 10/01/04 to 09/30/05
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 the most commonly used management strategy to control soilborne diseases, nematodes, and weeds in high value fruits, nuts, vegetables, nursery crops, and ornamentals. Availability of methyl bromide was restricted in January 2001 to 50% of the amount used in the baseline year of 1991 and was further restricted to 30% of the baseline in 2003. It was completely banned in 2005 except for uses with approved Critical Use Exemptions (CUE) or Quarantine/Preshipment (QPS) uses. CUEs are granted on a one-year basis. Strawberry, orchard and vineyard replant, ornamentals, and perennial nurseries have received Critical Use Exemptions for 2005 and 2006. U.S. growers of these high value crops are in dire need of alternatives to the use of methyl bromide. The methyl bromide phase-out will
result in an estimated 50% yield reduction in some crops and large economic losses, especially in strawberry, ornamental, and nursery crops, if effective alternatives are not found and CUEs are not granted. The availability, or lack thereof, of acceptable alternatives will in turn, impact the supply and quality of these commodities to American consumers and the export market. Pre-plant soil fumigation with methyl bromide is used to control "replant disorder," meet regulatory requirements for clean propagative material, and control weeds and soilborne pathogens for many high value crops including grapes, stone fruit and nut trees, strawberries, nursery crops, and ornamentals. The phase out of methyl bromide highlights two major challenges. The first is to quickly find effective control measures that are economically feasible, fit current cropping systems, and are acceptable to environmental and regulatory agencies. We are approaching this challenge by testing unregistered
chemicals, novel applications of currently available chemicals, and new application technologies to deliver effective concentrations of materials to the target pests. Our team expertise in crop production, plant pathology, nematology, irrigation management, and soil chemistry, provides us the tools to address the biological, chemical, and engineering aspects of this project. Our current results indicate that this approach will meet the short-term to mid-term need. The second challenge is to increase our understanding of the pathogens and soil factors limiting crop production. A successful, long-term, integrated management approach requires a thorough understanding of biological, chemical, and physical soil factors, their interactions, and their spatial variability, and will include cultural, genetic, biological and chemical management strategies. Greenhouse, microplot, and field studies will generate new knowledge of these interactions and their responses to currently available and
newly developed management strategies. Innovative adaptations of drip irrigation technologies to develop a delivery system for biological and chemical management options offer the potential for greater flexibility and increased responsiveness to spatial variability. A better understanding of the causes of poor plant vigor in high value annual and perennial crops will lead to more science-based selections of management strategies. Effective, economic, environmentally acceptable pest and pathogen management strategies will contribute to the on-going productivity of high value annual and perennial cropping systems and the continued availability of clean planting stock from certified nurseries. The ultimate result will be a safe, dependable, high quality, and affordable food and flower supply for domestic and foreign markets, on- going productivity of crop production systems (many of them family farms), and protection of the environment. Some of the knowledge gained may be specific to
a particular crop production system or to California conditions, however, general principles regarding pathogen and pest management, technology and application methods, economics of alternative systems, irrigation and nutrient management, and precautions for providing environmental protection will be transferable to other crops and areas. Anticipated products from this project include new knowledge of, and diagnostic methodologies for, determining the causes of poor plant vigor in strawberry, ornamental, perennial, and nursery production systems in the absence of methyl bromide fumigation; new pest and pathogen management strategies that utilize new knowledge and novel application methods to effectively and economically control pests and pathogens while protecting the environment; field scale demonstrations of alternative management strategies, conducted in partnership with growers; growers who continue to be competitive in the world market; and safe, dependable, high quality,
affordable food and flower supplies. This work is relevant to producers of high value crops who currently use methyl bromide, Cooperative Extension personnel, pest control advisors, crop consultants, and scientists interested in the complex interactions between biological, physical, and chemical soil factors and their impact on crop growth, yield, and quality. The potential impact of this work is to substantially change soilborne pest and pathogen management for high value crops to strategies that are practical, economically feasible, and environmentally acceptable. 2. List the milestones (indicators of progress) from your Project Plan. Pathogen Isolation 1. Pathogens from diseased materials from multiple ornamental field trials isolated and identified. 2. Pests and pathogens involved in peach and grape replant disorder isolated, identified and evaluated for cross-specificity. Pathogenicity 3. Organisms isolated from ornamental fields tested for pathogenicity on various hosts
according to Koch's postulates. Management Strategies 4. Rate studies of various methyl bromide alternatives conducted for cut flower production. 5. Various biocontrol agents for control of root disease on calla lily evaluated in greenhouse trials. 6. Microplot trials initiated to evaluate potential post-plant nematode control strategies for established perennial cropping systems. 7. Microplot trials initiated of combinations of chemical strategies as alternatives to methyl bromide for perennial, nursery, and ornamental crops. 8. Vineyard replant trials planted in 1998 and 1999 completed. 9. Long-term orchard replant fumigant small-plot field trials completed including data analysis and economic analysis. 10. Long-term fallow small-plot field trials for perennial replant completed including data analysis, economic analysis, and publication of results. 11. Nematode control and grapevine growth and yield three to six years after treatment (alternative fumigants, long term fallow,
resistant rootstocks) evaluated in vineyard replant trials. 12. Field efficacy/phytotoxicity of 2-bromo ethanol (Agent 2B) evaluated. Application Technologies and Emission Reduction 13. Lab bench experiments conducted to evaluate important factors including soil types and water content affecting fumigant degradation in soils. 14. Effects of fumigation methods evaluated in small field plots in combination with soil surface sealing techniques to reduce fumigant emissions of toxics and volatile organic compounds (VOCs). 15. Field and modeling study conducted to determine water application management practices that maximize lateral distribution of drip applied fumigants. Field Trials and Commercial Demonstrations 16. Almond nursery trial in commercial field completed. 17. Efficacy of drip applied alternative fumigants in fine-textured soils evaluated under commercial conditions for perennial nursery cropping systems. 18. Drip-applied fumigant treatments compared with standard shank-
injected fumigants for certified nursery crops on grower fields. 19. Alternative fumigants for nut tree orchard replant evaluated in commercial fields. 20. 2-4 field trials conducted to determine fumigant (e.g., cis-1,3- dichloropropene, trans-1,3-dichloropropene, and chloropicrin) distribution, dissipation, and degradation in soil profiles under drip and shank applications. 21. Additional cut flower trials established with new and emerging products. 22. New field trials of alternatives to methyl bromide for 2-year field nursery crops (roses and trees) initiated in commercial fields. 23. Third field trial of no-till strawberries initiated. 3a List the milestones that were scheduled to be addressed in FY 2005. For each milestone, indicate the status: fully met, substantially met, or not met. If not met, why. 1. Pathogens from diseased materials from multiple ornamental field trials isolated and identified. Milestone Fully Met 2. Pests and pathogens involved in peach and grape
replant disorder isolated, identified and evaluated for cross-specificity. Milestone Fully Met 3. Organisms isolated from ornamental fields tested for pathogenicity on various hosts according to Koch's postulates. Milestone Fully Met 4. Rate studies of various methyl bromide alternatives conducted for cut flower production. Milestone Fully Met 5. Various biocontrol agents for control of root disease on calla lily evaluated in greenhouse trials. Milestone Fully Met 6. Microplot trials initiated to evaluate potential post-plant nematode control strategies for established perennial cropping systems. Milestone Not Met Other 7. Microplot trials initiated of combinations of chemical strategies as alternatives to methyl bromide for perennial, nursery, and ornamental crops. Milestone Fully Met 8. Vineyard replant trials planted in 1998 and 1999 completed. Milestone Not Met Other 9. Long-term orchard replant fumigant small-plot field trials completed including data analysis and economic
analysis. Milestone Substantially Met 10. Long-term fallow small-plot field trials for perennial replant completed including data analysis, economic analysis, and publication of results. Milestone Substantially Met 11. Nematode control and grapevine growth and yield three to six years after treatment (alternative fumigants, long term fallow, resistant rootstocks) evaluated in vineyard replant trials. Milestone Fully Met 12. Field efficacy/phytotoxicity of 2-bromo ethanol (Agent 2B) evaluated. Milestone Fully Met 13. Lab bench experiments conducted to evaluate important factors including soil types and water content affecting fumigant degradation in soils. Milestone Substantially Met 14. Effects of fumigation methods evaluated in small field plots in combination with soil surface sealing techniques to reduce fumigant emissions of toxics and volatile organic compounds (VOCs). Milestone Fully Met 15. Field and modeling study conducted to determine water application management practices
that maximize lateral distribution of drip applied fumigants. Milestone Not Met Other 16. Almond nursery trial in commercial field completed. Milestone Fully Met 17. Efficacy of drip applied alternative fumigants in fine-textured soils evaluated under commercial conditions for perennial nursery cropping systems. Milestone Fully Met 18. Drip-applied fumigant treatments compared with standard shank-injected fumigants for certified nursery crops on grower fields. Milestone Fully Met 19. Alternative fumigants for nut tree orchard replant evaluated in commercial fields. Milestone Fully Met 20. 2-4 field trials conducted to determine fumigant (e.g., cis-1,3- dichloropropene, trans-1,3-dichloropropene, and chloropicrin) distribution, dissipation, and degradation in soil profiles under drip and shank applications. Milestone Fully Met 21. Additional cut flower trials established with new and emerging products. Milestone Fully Met 22. New field trials of alternatives to methyl bromide for
2-year field nursery crops (roses and trees) initiated in commercial fields. Milestone Substantially Met 23. Third field trial of no-till strawberries initiated. Milestone Not Met Progress slowed by resource limitation (human,fiscal,equipment, etc. 3b List the milestones that you expect to address over the next 3 years (FY 2006, 2007, and 2008). What do you expect to accomplish, year by year, over the next 3 years under each milestone? FY2006 - Annual Milestones Pathogen Isolation Impacts from milestones 1 and 2 will be better diagnostic capabilities and therefore more science-based selections of management options as alternatives to methyl bromide. 1. Pathogens from diseased materials isolated from the various ornamental field trials. Pathogenicity 2. Organisms isolated from ornamental fields tested for pathogenicity on various hosts according to Koch's postulates. Management Strategies Impacts from milestones 12-16 will be additional technically and economically acceptable
management strategies to use either alone or in combination as alternatives to methyl bromide for ornamental crops, perennial replant situations, and field-grown propagative material crops. 3. Rate studies conducted of various methyl bromide alternatives for cut flower production. 4. Dose-rate response experiments will be conducted in the lab with various emerging chemicals on pathogens, nematodes, and weeds important in ornamental cropping systems. 5. Field efficacy/phytotoxicity evaluations of 2-bromo ethanol (Agent 2B) completed. 6. Perennial crop yield and nematode control 3-5 years after treatment (alternative fumigants, fallow and resistant rootstocks) evaluated in vineyard replant trials. 7. Long term trials to evaluate perennial crop yield and nematode control under vineyard replant conditions 6-8 years after treatment completed, unless results indicate that maintaining trials an additional year would be of great benefit. 8. Microplot studies initiated to evaluate of
potential alternatives to methyl bromide for perennial and nursery cropping systems. 9. Microplot trial initiated to evaluate post-plant nematicides in perennial cropping systems. 10. Data and economic analysis completed for 5 orchard replant field trials and manuscripts written and submitted. 11. Two field trials on orchard and/or nursery crops established to compare drip and shank application of 1,3-D and chloropicrin under field conditions. Application Technologies and Emission Reduction 12. Column experiments conducted to evaluate effect of surface water seals, alone and in combination with plastic tarps, on reducing fumigant emissions from different types of soils. 13. Emission reduction studies expanded to other potential fumigants such as iodomethane. 14. Soil surface sealing techniques and other management practices that reduce fumigant emissions of toxics and VOCs in field trials evaluated. 15. Field trials conducted in different soil types and at different seasons, in
combination with tarps, to study fumigant distribution in soils and emissions with drip and shank applications. 16. Field tests and computer modeling carried out to optimize water/fumigant application practices for drip fumigation. Field Trials and Commercial Demonstrations 17. Establish new cut flower trials with new and emerging products. 18. Almond and walnut nursery trials in commercial fields completed. 19. Initiate new 2-year field nursery crop trial in commercial fields, if field with adequate pest pressure is available. 20. Orchard replant trials in commercial fields initiated in FY04 on- going (Madera trials). 21. Complete evaluation of 2 alternative fumigant orchard replant field trials (Enns trials). 22. Two field trials with orchard crops established to compare drip and shank application of 1,3-D and chloropicrin under field conditions. 23. Two field trials of no-till strawberries carried out. FY2007 - Annual Milestones Pathogen Isolation 1. Pathogens from diseased
materials isolated from the various ornamental field trials. Pathogenicity 2. Organisms isolated from ornamental fields tested for pathogenicity on various hosts according to Koch's postulates. Management Strategies 3. Rate studies conducted of various methyl bromide alternatives for cut flower production. 4. Perennial crop yield and nematode control 4-6 years after treatment evaluated in vineyard replant trials. 5. Establish additional microplot trials with to evaluate potential methyl bromide alternatives for pre-plant fumigation. 6. Microplot trial to evaluate post-plant nematicides for perennial production systems continued. 7. Additional microplot trial initiated to evaluate post-plant nematicides in perennial cropping systems. Application Technologies and Emissions Reductions 8. Mass balance approach used to evaluate the fate of fumigants after applying to soils. 9. Practical soil surface sealing techniques and other management practices that can reduce fumigant
emissions of toxics and VOCs tested in large field trials. 10. Findings on fumigant fate (distribution, dissipation, and emissions) and application methods, are compiled, analyzed and published. 11. Work with cooperators to model fumigant emissions under varying soil types, climatic conditions, and cultural practices. Field Trials and Commercial Demonstrations 12. Additional cut flower trials established with new and emerging products. 13. 2-year nursery crop trial that was initiated in commercial field nurseries in FY 06 continued. 14. Orchard replant trials in commercial fields initiated in FY04 completed (Madera). 15. Large field trial of no-till strawberries conducted. 16. On-going evaluations conducted for orchard replant trials in commercial fields initiated in FY06. 17. Soil surface sealing techniques and other management practices that reduce fumigant emissions of toxics and VOCs demonstrated in large field plots. FY2008 - Annual Milestones Pathogen Isolation 1.
Pathogens will be isolated from floricultural crops not studied before. Pathogenicity 2. Isolated pathogens will be tested according to Koch's postulates. Management Strategies 3. Rate studies conducted of various methyl bromide alternatives for cut flower production. 4. Perennial crop yield and nematode control 5-7 years after treatment evaluated in vineyard replant trials. 5. Evaluation of performance in microplot trials of post-plant nematicides for perennial production systems continued. 6. Establish additional microplot trials with new and emerging products for pre-plant fumigation. Application Technologies and Emissions Reductions 7. Large field trial conducted to further test practical management methods (e.g., water seal and in combination with tarps) to maximize reduction of fumigant emissions. 8. Studies conducted to determine lethal dosages of alternative fumigants. 9. Studies conducted to determine optimum conditions for using lower rates of fumigant that can
achieve fumigation efficacy while minimizing emissions. 10. Model developed and tested that can predict the effect of management practices on fumigant emissions for various soil types and climatic conditions. 11. Additional data required to register management practices that reduce fumigant emissions is collected and summarized. Field Trials and Commercial Demonstrations 12. Field trials will be conducted in floriculture cropping systems not studied before using standard as well as emerging chemicals. 13. 2-year nursery crop trial that was initiated in FY06 in commercial field nurseries completed. 14. On-going evaluations carried out for orchard replant trials in commercial fields initiated in FY06. 4a What was the single most significant accomplishment this past year? Methyl bromide alternatives for calla lily production. A four year, two location study to evaluate drip applied alternative chemicals for the replacement of methyl bromide for the production of calla lily
rhizomes was completed by the San Joaquin Valley Agricultural Sciences Center Methyl Bromide Research Team, in collaboration with Golden State Bulb Growers. Alternatives included iodomethane, 1,3-dichloropropene, chloropicrin, and metam sodium and combinations of the above. Significant disease control was achieved compared to nontreated control and was comparable to the standard methyl bromide treatment. Weed control may be lacking when these chemicals are applied by drip irrigation. As a result of this research, drip-applied alternative chemicals are now used in some commercial production. Acceptance of these methyl bromide alternatives will increase as growers become more familiar with drip-applied fumigants. 4b List other significant accomplishments, if any. Use of surface water application to reduce 1,3-D emissions. Soil column tests were conducted by San Joaquin Valley Agricultural Sciences Center Methyl Bromide Research Team to evaluate surface water application, alone, and
in combination with plastic tarps, to reduce emissions of 1,3- dichloropropene. Results demonstrate that surface water applications can reduce emissions to a level comparable to, or less than, with standard HDPE tarp. Intermittent water applications were more effective in reducing emissions particularly within a short period of time after water application but reduction on the overall emission over a 2 week period was relatively small. These results will lead to the development of improved application technologies for methyl bromide alternatives that will reduce emission and improve efficacy. Methyl bromide alternatives for cut flower production. Four field trials were established by San Joaquin Valley Agricultural Sciences Center Methyl Bromide Research Team to test drip-applied alternatives for the production of dutch iris, snapdragon, stock, and gypsophila. Alternatives included iodomethane, 1,3-dichloropropene , chloropicrin, and metam sodium. Results indicate disease and weed
control is comparable to the standard methyl bromide treatment. Growers are interested in the results, but would like to see further testing. Grapevine Nursery Trial. Three drip-applied fumigants were evaluated as methyl bromide alternatives for field-grown nursery cropping systems at the San Joaquin Valley Agricultural Sciences Center. Sodium azide, 1,3- dichloropropene (1,3-D) + chloropicrin (Pic), and iodomethane (IM) + Pic were applied to a rootknot nematode infested field prior to planting grape nursery "sticks". When plants were harvested at the end of the one year cropping cycle, root galls (which make the vines unmarketable) were found on 92% of the Thompson Seedless and 100% of the Cabernet Sauvignon plants in untreated plots, 67% of the Cabernet Sauvignon and 54% of Thompson Seedless in azide treated plots, and were absent in the methyl bromide, 1,3-D + Pic, and IM + Pic treated plots. These results suggest that 1,3-D+Pic and IM+Pic are good candidates as alternatives
to methyl bromide on the California Department of Food and Agriculture "approved Certified Nursery soil treatment list" for sandy loam soils. Strawberry Fumigation Training Manual. Substantial research evaluating and testing methyl bromide alternatives for strawberries has been completed and demonstrated, but over half of strawberry growers continue to use methyl bromide and Critical Use Exemptions continue to be requested. A training manual for use of methyl bromide alternatives in strawberries was written by San Joaquin Valley Agricultural Sciences Center Methyl Bromide Research Team in cooperation with the CA Strawberry Commission and Univ. of Calif. Cooperative Extension. A series of 4 workshops on adoption of alternatives was conducted by UCCE and CSC using the Manual, and a chapter on drip fumigation methods was written for the UC Strawberry IPM Manual. With the aid of these training materials, adoption of alternatives in CA strawberries is growing at over 20% per year. 4c
List any significant activities that support special target populations. A report and presentation on Improving Strawberry Irrigation Systems was translated in Spanish and provided to UCCE for presentation to Hispanic strawberry growers. Efficient irrigation systems are required for effective drip fumigation. 4d Progress report. The USDA ARS SJVASC's Methyl Bromide Research Team received more than $132,500 in funding from competitive grants, grower groups, and methyl bromide alternatives manufacturers, in addition to significant in-kind contributions of plants, land, labor, and chemical products. Drip vs. shank-injected fumigation. Standard shank-injected fumigation and drip fumigation were compared in three field nursery trials in commercial fields located at Brights Nursery, Dave Wilson Nursery, and Sierra Gold Nursery by the San Joaquin Valley Agricultural Sciences Center Methyl Bromide Research Team. Nursery growers will need technically and economically feasible alternatives
to methyl bromide in the production of pest- and pathogen- free propagative material. Bags containing plant parasitic nematodes were buried at 6, 12, 24, and 36 inch soil depths prior to fumigation. Nematode control by drip-applied 1, 3-dichloropropene (1,3-D) alone, 1,3-D + chloropicrin (Pic), and iodomethane (IM) + Pic was comparable to standard shank-injected formulations of the same materials at the 6" and 12" soil depths, but drip-applied fumigation was not as effective as shank-injected fumigation for nematode control at the 24" and 36" soil depths in these finer- textured soils. These results document the difficulty of obtaining effective fumigant distribution in fine-textured soils. Acceptable MB alternatives for fine-textured soils are still a critical need and an on- going priority for ARS research. These trials will be harvested in winter 2005/06. Perennial field nursery and orchard replant trials. Three nut tree nursery and two nut orchard replant trials are on-going
in commercial fields as part of a large team project including Drs. G. Browne (ARS Davis, CA), S. Schneider and T. Trout (both San Joaquin Valley Agricultural Sciences Center Methyl Bromide Research Team), and B. Lampinen and A. Shrestha (both UC Davis). Trials are located at Brights Nursery, Sierra Gold Nursery, Dave Wilson Nursery, and Agriland. Bags containing weed seed were buried at 3 inch soil depth and bags containing fungal pathogens and plant parasitic nematodes were buried at 6, 12, 24, and 36 inch soil depths prior to fumigation. Control of these pests and pathogens by tarped, shank-injected 1,3-D (Telone II), iodomethane + chloropicrin (Midas), and 1,3-D + chloropicrin (Telone C35) was comparable to methyl bromide at all depths in coarse-textured soils, but control of fungi and nematodes was not as good as methyl bromide at the deeper soil depths in finer-textured soils. The nursery trials will be completed winter 2005/06. The orchard replant trials are on-going.
Long-term fallow for perennial replant. The effects of 1, 2, and 3 years of dry fallow were tested on peaches, plums, and grapes by San Joaquin Valley Agricultural Sciences Center Methyl Bromide Research Team. Peaches, plums, and grapes re-planted in the plots in 2000, are in their 6th year of growth, and 3rd or 4th year of production. One year of fallow increased yields in all stonefruit trials by 10 to 20%, and treating tree stumps with systemic herbicide (Roundup) did not increase growth or yield compared to one year fallow in one trial. In both peaches and plums, each additional year of fallow increased growth and yield with 3 years of fallow giving similar yields to that produced with methyl bromide fumigation. In the grape trial, after 5 years of growth, there was no significant difference in yield for any treatment (untreated, methyl bromide, or 1-3 year fallow) for all three scion/rootstock combinations tested. Vines grown in untreated plots and plots following a 1 year
fallow had significantly smaller trunk diameters than vines grown in methyl bromide treated plots for two of the three scion/rootstock combinations tested. Alternatives to methyl bromide for vineyard replant. In a vineyard replant trial conducted by the San Joaquin Valley Agricultural Sciences Center Methyl Bromide Research Team, rootknot nematode populations on a susceptible grape variety in plots treated with drip-applied propargyl bromide or InLine (drip-applied 1,3-dichloropropene + chloropicrin) were not significantly different after 4 growing seasons from populations in plots treated with methyl bromide. Plots treated with sodium azide, drip- applied chloropicrin, shank-injected propargyl bromide or an herbicidal- rate of metam sodium supported rootknot nematode populations that were not significantly different from the untreated control plots. Nematode control in plots treated with shank-injected or drip-applied iodomethane + chloropicrin was intermediate in efficacy; not
as poor as untreated, but not as good as methyl bromide. These trials are on-going. Methyl bromide alternatives for vineyard replant. A vineyard replant trial, planted in a field at the San Joaquin Valley Agricultural Sciences Center from which 60+year old grapevines were removed, all treatments, including InLine (drip-applied 1,3-dichloropropene + chloropicrin) , Midas (iodomethane + chloropicrin), and sodium azide controlled plant parasitic nematodes to a depth of five feet at the time of planting. After the 1st and 2nd full growing seasons, rootknot nematode populations on Thompson Seedless in plots treated with sodium azide were comparable to populations in untreated plots while populations in InLine and Midas treated plots were comparable to methyl bromide. Plants grown in methyl bromide treated plots were significantly larger than plants grown in all other treatments. This trial, which will continue for several more years, documents the necessity of measuring not only
initial nematode control, but also nematode control over time and plant growth and yield in order to evaluate the potential as a methyl bromide alternative for perennial cropping systems. Fumigant distribution with shank- and drip applications under field conditions. Improving uniformity of fumigant distribution and reducing fumigant emissions are key components to enhancing the efficacy of fumigant alternatives to methyl bromide, addressing environmental concerns associated with Volatile Organic Compounds (VOCs) and insuring compliance with environment-based regulatory restrictions such as the township caps placed on use of 1,3-dichloropropene. Field trials conducted by the San Joaquin Valley Agricultural Sciences Center Methyl Bromide Research Team demonstrated that emissions depend largely on fumigant properties, soil preparation and use of tarps, rather than application method (shank-injection vs. drip application). Regardless of application method, fumigant movement to deep
layers in the soil profile is primarily limited by application depth and presence of a low permeability plow layer. This indicates deep application or other means to enhance fumigant downward transport are necessary when soil pests are a concern deep in the soil profile. Shank application results in higher fumigant concentrations in soil gaseous phase than drip application, but the opposite is true for fumigant concentrations in the soil liquid/solid phase. Fumigant distribution in soil profiles following drip-application demonstrate that gaseous phase and liquid/solid phase were affected by spacing of drip tapes and further document that appropriate spacing is required in drip application of fumigants for specific soils in order to achieve good efficacy and lead to more efficacious drip fumigation. 5. Describe the major accomplishments over the life of the project, including their predicted or actual impact. All accomplishments are linked to Component I of the Action Plan for
National Research Program 308 - Alternatives to Methyl Bromide. - Pathogen Isolation - Pathogenicity - Management Strategies Fumigant field trials for cut flower production. Pathogenicity tests determined the organisms causing disease in floriculture crops include Pythium sp. on calla lily, Cylindrocladium on myrtle, and Fusarium oxysporum on freesia. Field trials were conducted to evaluate alternative chemicals (iodomethane + chloropicrin (Midas), 1,3-D + chloropicrin (InLine), and furfural) for pathogen and weed control in freesia, stock, snapdragon, iris, Gypsophila and calla lily production systems. Treatments containing chloropicrin (Midas and InLine), applied with drip-fumigation technologies, resulted in per acre yields comparable to those the grower obtained with the standard methyl bromide + chloropicrin fumigation. Furfural alone had little or no weed or pathogen control activity and is not a technically feasible alternative to methyl bromide for weed or pathogen
control in cut flower production systems. Alternative chemicals were shown, in some cases, to be useful as methyl bromide alternatives. As a result of this research, bulb growers have started using drip irrigation technology to apply methyl bromide alternatives to their production fields resulting in a cost savings by eliminating in-season fungicide applications. The research is being used by growers, the California Cut Flower Commission, and U.S. EPA. This research was used to support the U.S. EPA Critical Use Nomination for ornamental crops and contributed to the granting of a Critical Use Exemption for cut flower growers for 2005 and 2006. Efficacy of propargyl bromide. A multi-agency (USDA and university) and multi-state (CA and FL) effort to determine the efficacy of propargyl bromide as a soil fumigant was carried out by 14 scientists from 6 locations (T. Trout, S. Schneider, H. Ajwa, M. Schutter USDA-ARS, Fresno, CA; F. Martin, USDA-ARS, Salinas, CA; K. Subbarao, S.
Fennimore, Univ. CA, Salinas, CA; G. Browne, USDA-ARS, Davis, CA; B. Westerdahl, C. Elmore, U. C. Davis; C. Winterbottom, California Strawberry Commission, Watsonville, CA; E. Rosskopf, USDA-ARS, Ft. Pierce, FL; J. Noling, Univ. of Florida, Lake Albert, FL; J. Norton, USDA IR-4 Methyl Bromide Alternatives Program, FL) with USDA funding. The studies on tomato, strawberry, carrot, fruit trees, grape vines, and ornamentals determined that propargyl bromide is efficacious against most pests including nematodes, diseases, and weeds at rates above 100 pounds per acre, which is about 1/3 the current methyl bromide use rate, and generally resulted in good plant growth and yield, although some phytotoxicity was noted in two trials. These coordinated studies indicate that propargyl bromide can be an efficacious replacement for methyl bromide. Unfortunately, there is currently no private sector interest in pursuing registration of this material. Efficacy of fallow as an alternative to methyl
bromide for perennial replant. The benefit of one, two, and three years of dry fallow as an alternative to methyl bromide for perennial replant disorder was quantified for peaches, plums, and grapes. After five years of growth, and two or three years of fruit production, one year of fallow increased yields in all stonefruit trials by 10 to 20%. In peaches and plums, each additional year of fallow increased growth and yield, with three years of fallow giving similar yields to that produced with methyl bromide fumigation. In the grape trial, after 4 years of growth, vine trunk diameters in plots following 3 years fallow were comparable in size to vines grown in methyl bromide treated plots for all three scion/rootstock combinations tested. Vines grown in untreated plots and plots following a 1 year fallow had significantly smaller trunk diameters than vines grown in methyl bromide treated plots for two of the three scion/rootstock combinations tested. The beneficial impact of the
increasing length of the fallow period was detectable in citrus nematode populations (Tylenchulus semipenetrans) only for the first growing season and only in the upper soil layers, while rootknot nematode populations (Meloidogyne spp.) differed as a function of the length of the fallow for three growing seasons. Nematode populations of both genera remained significantly lower in methyl bromide fumigated plots after four growing season than in all fallow treatments. Economic analysis indicated that the costs associated with 3 years of fallow were less expensive than methyl bromide fumigation, but more expensive than Telone fumigation. Fallowing presents a treatment alternative for growers that face replant disease but prefer not to fumigate. Alternatively, fallowing can be combined with other methyl bromide alternatives, such as a nematicide or resistant rootstock, for a more robust MB alternative than fallow alone. Efficacy of iodomethane. Determined iodomethane to be comparable
to methyl bromide for perennial replant, field nurseries, ornamental, and strawberry cropping systems. Registration of this methyl bromide alternative is actively underway in the private sector. - Application Technologies and Emissions Reductions Soil water model for improved drip fumigation. Effective drip application of fumigants depends upon delivering the fumigants to the target soil zone. Computer models are useful to evaluate management practices to enable precision placement of the water and fumigants. Field data was collected to validate a two-dimensional soil water flow model for conditions of drip irrigation in collaboration with ARS- Riverside. Hydrus 2-D was able to model the collected data very well using only soil particle size data to determine hydraulic parameters. This research will be used to determine management practices that maximize horizontal water movement and drip fumigant distribution from drip lines to improve efficacy and consistency of drip-applied
fumigants. - Field Trials and Commercial Demonstrations Drip-application technologies for pre-plant fumigants. Over 80% of the commercial strawberries in the US are grown in California. This $1 billion industry has relied on methyl bromide soil fumigation to prepare their fields. California strawberry growers have received a Critical Use Exemption for 3 million pounds of methyl bromide for use in 2006. Through 5 years of field research trials in collaboration with manufacturers, applicators, and growers, the San Joaquin Valley Agricultural Sciences Center Methyl Bromide Research Team has demonstrated that drip fumigation is effective and has developed management practices to maximize efficacy. In 2001, manufacturers and applicators received registration from EPA to apply two alternative fumigants, 1,3-Dichloropropene (Telone) and chloropicrin, by drip fumigation. Through 6 years of trials on commercial strawberry fields, including 23 field demonstration trials, we developed
application equipment and procedures, and demonstrated the technology to growers. In its first year of registration, InLine, a combination of these two fumigants formulated for drip application, was applied to 900 acres of strawberries. In 2002, this product and an emulsified chloropicrin (TriChlor EC) were applied to 3200 acres, over 10% of the strawberry crop with a potential value of $90 million. In 2004, the California Strawberry Commission reported that 35% of the 33,000 acres of strawberries were using alternatives to methyl bromide, the majority of these were drip-applied using technologies developed by ARS. Drip fumigation is also being used on melons (2000 ac in 2000 and 2001) and peppers (1200 ac in 2000/2001), crops that are cultivated on plastic- mulched, drip-irrigated beds similar to strawberries. Growers like this application method because it is inexpensive and reduces worker risk. It may also reduce fumigant emissions and risks to neighbors. Our drip-
application technology has also been tested and demonstrated under commercial conditions in two orchards, three nut tree nursery fields and one rose nursery field in addition to numerous research plots located on the California coast and in the San Joaquin Valley. This research was used to support the U.S. EPA Critical Use Nomination for strawberry cropping systems and contributed to the granting of a Critical Use Exemption for 2005 and 2006. Replant Disorder Field Trial. Perennial crops are not treated every cropping season, as are annual crops, but only when the orchard or vineyard is replanted. Stonefruit, nut tree and vine growers face significant challenges to control soil pests and reduce the effects of the "replant disorder" when replacing existing orchards and vineyards. Several alternatives were tested in replanted peach, plum, and almond orchards and vineyards in a series of field trials located at the San Joaquin Valley Agricultural Sciences Center and in growers' fields
in Dinuba and Madera, CA. Emulsified formulations of alternative fumigants 1, 3 dichloropropene (1,3-D) and chloropicrin applied through subsurface drip irrigation systems produced tree growth and yield equal to methyl bromide. InLine (1,3-D + chloropicrin) provided nearly equal benefits in growth and yield when replanting fruit tree orchards where replant disorder was a problem but there were no acute pathogens or nematodes. 1, 3-D and chloropicrin resulted in increased early growth and vigour and about 20% increase in yield over years 3 - 6. The yield impact declines with tree maturity. Economic analysis showed that 1,3-D fumigation is economically beneficial, while more expensive methyl bromide fumigation provides marginal returns under the above conditions. Control of plant parasitic nematodes in vineyard replant plots following treatment with 1, 3-D + chloropicrin, iodomethane + chloropicrin, or propargyl bromide was comparable to control achieved by methyl bromide for up to
6 growing seasons after treatment irrespective of whether conventional shank- injection or drip-fumigation application technologies were used. Shank- injection and drip application of currently registered and unregistered materials can provide growers with alternative soil treatments in sandy loam soils that provide control similar to that achieved with methyl bromide. This research was used to support the U.S. EPA Critical Use Nomination for perennial replant situations and contributed to the granting of a Critical Use Exemption for 2005 and 2006. Methyl bromide alternatives for 2-year field nursery crops. Tree and rose nurseries (propagative materials), grown in the open field for one to two years, commonly use methyl bromide as a preplant soil fumigant to control soilborne pathogens, pests, and weeds and to comply with California regulations governing certified nurseries. Alternative fumigants were applied by shank injection (tarped and untarped) and through drip irrigation in
trials located at commercial tree and rose nurseries. 1,3-dichloropropene + chloropicrin and iodomethane +chloropicrin provided control, in sandy loam soils, of plant parasitic nematodes similar to methyl bromide down to a soil depth of five feet (150 cm) at the time of planting, resulted in soil nematode populations similar to methyl bromide after one growing season, and when tarped, resulted in the harvest of nematode-free two-year crops (as required by the clean propagative material regulations) that were similar in quality to crops grown in methyl bromide treated soil. This research was used to support the U.S. EPA Critical Use Nomination for nursery cropping systems and contributed to the granting of a critical use exemption for 2005 and 2006. Irrigation Distribution Uniformity in Commercial Fields. Effective and efficient drip application of fumigants depends on uniform distribution of the fumigants and water through the drip irrigation system. Irrigation distribution
uniformity was measured on 39 strawberry fields throughout the strawberry growing regions of California. Distribution uniformity varied from 45% to 93% and averaged 81% (a value that is disappointingly low for a precision system that can achieve over 90% uniformity) which results in a need for one-quarter additional water (or drip applied fumigant) to achieve the target amount on the drier areas of the field. This work identified problems related to improper design (beds too long), equipment (connector spaghetti tubing too small), and management (non-uniformly set valves). These results and recommendations were presented to strawberry growers in 6 irrigation workshops and will result in improvements in strawberry irrigation and drip fumigation. No-till strawberry production. Strawberry growers consume time, energy, water, and money preparing a strawberry field for the following years strawberry planting. With drip fumigation, these costs could be reduced by reusing the previous
strawberry beds. A no-till study of strawberry was initiated by the San Joaquin Valley Agricultural Sciences Center Methyl Bromide Research Team in 2001 in which strawberries are replanted on the same planting beds in consecutive years following removal of the previous plants, replacement of the drip tape and tarp, and drip fumigation. This process reduces production costs by over $600 per acre, reduces water use, and reduces plant-back time (and thus extends harvest time of the previous crop) by 2 to 3 weeks. Results from the two-year field trial completed at Salinas showed no yield loss with bed reuse and current year yields show no yield decline for third year use of the same beds. Evaluation of Impact of Township Caps on Availability of 1,3- dicholoropropene. Use of 1,3-dichloropropene (Telone) in California is limited by state "township cap" regulations. California pesticide use databases maintained by the state were analyzed to determine fumigant use trends and the likely
impact of township caps on adoption of fumigants that contain this chemical as alternatives to methyl bromide. The analysis showed severe impacts on certain commodities and geographic areas. These data are being used extensively by US EPA and Parties to the Montreal Protocol to evaluate Critical Use Exemption nominations for continued methyl bromide use for those circumstances where 1,3-D would be the only viable alternative, but is not expected to be available due to township caps. 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? The 5th annual Field Day for Methyl Bromide Alternatives for CA Tree, Vine, and Nursery Crops featuring tours of our field trials located on the SJVASC research station was conducted at the end of last field season
(attendance > 40). Growers and industry representatives were able to walk through field trials demonstrating the efficacy of currently unregistered materials, drip-irrigation as a fumigant application technology, long-term fallow, and resistant rootstocks as alternatives to methyl bromide in vineyard and orchard replant situations and for field grown perennial nurseries. Efficacy of alternative fumigants and drip fumigation technologies for ornamental cropping systems were presented at grower meetings. A field day with growers was conducted this summer showing the technology being used in the field. As a result of the transfer of our research results, calla lily rhizome growers are now using drip-applied soil fumigants on a portion of their crop. Oral presentations on Methyl Bromide Alternatives for perennial and nursery crops and the current status of the Critical Use Exemption process were presented to over 500 attendees in several forums (Almond Board of California Annual
Meeting; Annual Sweet Potato Workshop, Alliance for Alternative Agriculture symposium "The science and politics of soil fumigation", Duarte Nursery Friends Day, Minor Crops Tour, Pesticide Applicators Professional Association seminar, California Association of Nurserymen, California Cut Flower Commission, and California Strawberry Commission ). The 8th annual meeting of the Advisory Group for Methyl Bromide Alternatives for CA Perennial Crops was held in March for growers, industry representatives, and scientists to review the issues and to recommend research priorities (attendance > 30, minutes and handouts emailed to 100+ people). Presentation on strawberry irrigation was presented at the Annual Central Coast Strawberry Meeting. A section on efficient irrigation practices was prepared for the UCCE extension manual on alternatives to methyl bromide for strawberries. The Manual was used in 3 workshops on soil fumigation for strawberries sponsored by the CA Strawberry Comm. Numerous
individual tours of our field trials have been arranged for growers, industry, govt. agencies (U.S. EPA, USDA) university (including Cooperative Extension), ARS scientists, and the press. A monthly Brown Bag Lunch Seminar series continues to foster information exchange between SJVASC and the University of California's Kearney Agricultural Center. 7. List your most important publications in the popular press and presentations to organizations and articles written about your work. (NOTE: List your peer reviewed publications below). Presentations: Gerik, J. Methyl Bromide Alternatives and the CUE Process. Santa Barbara Flower and Nursery Growers Association. Santa Barbara, CA. Gerik, J. Alternatives to Methyl Bromide for Ornamental Crops - Research Update. California Cut Flower Commission. Aromas, CA. Schneider, S., T. Trout, J. Gerik, H. Ajwa, and J. Sims. Alternatives to Methyl Bromide for Rose Field Nursery Production Systems. Garden Rose Council. Davis, CA. June, 2005.
Browne, G., B. Lampinen, S. Schneider, and A. Shrestha. Alternatives to Methyl Bromide for Tree Nurseries - Update on Research Trials. California Association of Nurserymen - Deciduous Growers. Parlier, CA. June, 2005. Schneider, S. Critical Use Exemption Update. California Association of Nurserymen - Deciduous Growers. Parlier, CA. June, 2005. Schneider, S., and T. Trout. Fumigant Trends. California Association of Nurserymen - Deciduous Growers. Parlier, CA. June, 2005. Schneider, S. Critical Use Exemption Update. California Cut Flower Consortium. Aromas, CA. June, 2005. Schneider, S., and T. Trout. Fumigant Trends. California Cut Flower Consortium. Aromas, CA. June, 2005. Trout, T.J. Strawberry Irrigation Scheduling. Central Coast Strawberry Meeting. UCCE. Watsonville, CA Feb 3, 2005. Trout, T.J. California Industry Shifts to Fumigation Alternatives. The Science and Politics of Soil Fumigation. Pacific Ag Research and the Ag Alliance. Pismo Beach, CA Feb
11, 2005. Trout, T.J. Update on Fumigant Availability and Use. 40th Annual Sweetpotato Meeting. UCCE. Merced, CA Feb 2, 2005. Trout, T.J. and S. gao. 32nd Almond Industry Conference, Almond Board of California. Modesto, CA. Trout, T.J. Fumigant Update. Minor Crops Tour. Minor Crops Council. Parlier, CA. July 26, 2005. Trout, T.J. Fumigant Use Trends. Duarte Nursery Field Day. Western Fruit Grower Magazine. Modesto, CA. May 6, 2005. Popular Press Articles written by us: Fumigant trends explored. California Farmer. May 2005. Popular Press Articles written about us: Farmers learn of fumigant choices. Fresno Bee. Sept, 2004. Researchers look for ways to improve irrigation of berries. Ag. Alert. Sept, 2004. No-till strawberry yields are comparable to conventional. Ag. Alert. Dec, 2004. Less tilling gives berries an edge. Madera Tribune. Feb, 2005. No-till shows promise on strawberries. Monterey Herald. Feb, 2005. Sweet potato meet - fumigants. Western Farm Press.
Apr, 2005. Replacing methyl bromide. Western Fruit Grower. June, 2005. Ajwa, H., T. Trout, and M. Bolda. 2005. Drip Fumigation. In: IPM Pest Management Guidelines - Strawberry. Published by Univ. of Calif. http://www.ipm.ucdavis.edu/PMG/r73900211.html Browne, G., J. Connell, S. McLaughlin, R. Lee, S. Schneider, and T. Trout. 2004. Potential of chemical and non-chemical approaches for managing Prunus replant disease. Proc. of the Annual International Research Conference on Methyl Bromide Alternatives and Emissions Reductions. pp. 8- 1 to 8- 5. Gao, S., T. Trout, S. Schneider, H. Ajwa, and G. Browne. 2004. Distribution and dissipation of 1,3-D and chloropicrin after shank and drip application in a clay loam soil. Proc. of the Annual International Research Conference on Methyl Bromide Alternatives and Emissions Reductions. pp. 80-1 to 80-4. Gerik, J. S. 2005. Evaluation of soil fumigants applied by drip irrigation for Liatris production. Plant Dis. 89:883-887. Gerik, J. S. 2005.
Drip applied soil fumigants for Liatris production. Phytopathology 95: s34. Gerik, J. S. 2004. Drip applied soil fumigants for calla lily production. Phytopathology 94: s34. Gerik, J. S. 2004. Soil fumigation for Freesia production. Proc. of the Annual International Research Conference on Methyl Bromide Alternatives and Emissions Reductions. pp. 85-1 to 85- 4. Gerik, J. S. 2004. Soil fumigation for Liatris production. Proc. of the Annual International Research Conference on Methyl Bromide Alternatives and Emissions Reductions. pp. 6-1 to 6- 4. Lampinen, B., G. Browne, S. Schneider, A. Shrestha, B. Holtz, and L. Simon. 2004. Alternative pre-plant soil fumigation treatments for deciduous tree crops. Proc. of the Annual International Research Conference on Methyl Bromide Alternatives and Emissions Reductions. Pp. 30-1 to 30-5 Schneider, S., T. Trout, and H. Ajwa. 2005. IPM as an alternative to methyl bromide for control of soil-borne pests in vineyard replant situations.
Phytopath. 95:S139-S140. Schneider, S., T. Trout, G. Browne, H. Ajwa, and J. Sims. 2004. Vineyard replant - performance of methyl bromide alternatives over time. Proc. of the Annual International Research Conference on Methyl Bromide Alternatives and Emissions Reductions. pp. 7-1 to 7- 5. Schneider, S., T. Trout, J. Gerik, H. Ajwa. 2004. Perennial crop nurseries - performance of methyl bromide alternative in the field. Proc. of the Annual International Research Conference on Methyl Bromide Alternatives and Emissions Reductions. pp. 29-1 to 29- 3. Schneider, S., T. Trout, J. Gerik, G. Browne and H. Ajwa. 2004. Alternatives to methyl bromide - the challenges of field nurseries and perennial crops. Nematropica 34:114-115. Skaggs, T.H., T.J. Trout, J. Simunek, P.J. Shouse. 2004. Comparison of HYDRUS-2D simulations of drip irrigation with experimental observations. J. Irrig. and Drainage Engr. 130(4):304-310. Trout, T., and N. Damodaran. 2004. Adoption of methyl bromide
alternatives by California strawberry growers. Proc. of the Annual International Research Conference on Methyl Bromide Alternatives and Emissions Reductions. pp. 35-1 to 35- 4. Trout, T., and S. Gao. 2004. Minimizing emissions from chloropicrin soil fumigation. 2004 Proc. 32nd Almond Industry Conf. p. 221-222. Trout, T., K. Klonsky and R. DeMoura. 2004. Economics of methyl bromide alternatives for orchard replant in California. Proc. of the Annual International Research Conference on Methyl Bromide Alternatives and Emissions Reductions. pp. 9-1 to 9- 5. Gao, S., Trout, T.J., Schneider, S.M., Ajwa, H., Browne, G.T. 2004. Distribution and dissipation of 1,3-d and chloropicrin after shank and drip applications in a clay loam soil. Proceedings of International Research Conference on Methyl Bromide Alternatives. Trout, T.J., Gao, S. 2004. Minimizing emissions from chloropicrin in soil fumigation. Meeting Abstract. Presentation Abstract fo 32nd Almond Industry Conference, Dec. 1-2,
2004, Modesto, CA.
Impacts
(N/A)
Publications
- Schneider, S.M., Trout, T.J., Ajwa, H.A. 2005. Ipm as an alternative to methyl bromide for control of soil-borne pests in vineyard replant situations. Phytopathology. Phytopathology 95: 5139-S/40.
- Schneider, S.M., Trout, T.J., Gerik, J.S., Ajwa, H.A. 2004. Methyl bromide alternatives for perennial crops and field nurseries.. Proceedings California Plant and Soil Conference Farming in Crisis. Feb. 2004. p. 104- 112.
- Schneider, S.M., Trout, T.J., Gerik, J.S., Ajwa, H.A. 2004. Perennial crop nurseries - performance of methyl bromide alternatiaves in the field.. Methyl Bromide Alternatives and Emissions Research Conference Proceedings. pp. 29-1 to 29-4.
- Schneider, S.M., Trout, T.J., Browne, G.T., Ajwa, H.A., Sims, J. 2004. Vineyard replant - performance of methyl bromide alternatiaves over time.. Methyl Bromide Alternatives and Emissions Research Conference Proceedings. pp 8-1 to 8-5.
- Gerik, J.S. 2005. Evaluation of soil fumigants applied by drip irrigation for liatris production.. Plant Disease. pgs. 883-887.
- Gerik, J.S. 2004. Soil fumigation for freesia production. Proceedings of International Research Conference on Methyl Bromide Alternatives. No volume number, pgs. 85-1 - 85-4.
- Gerik, J.S. 2004. Soil fumigation for liatris production.. Proceedings of International Research Conference on Methyl Bromide Alternatives. August 2005, pg. 883-887.
- Trout, T.J., Klonsky, K., De Moura, R. 2004. Economics of methyl bromide alternatives for orchard replant in california. Methyl Bromide Alternatives and Emissions Research Conference Proceedings, pp 9-1-5.
- Trout, T.J., Damodaran, N. 2004. Adoption of methyl bromide alternatives by california strawberry growers. Methyl Bromide Alternatives and Emissions Research Conference Proceedings, pp 35-1-4.
- Ajwa, H., Trout, T.J., Bolda, M. 2005. Drip fumigation. U.C. IPM Pest Management Guidelines - Strawberry. 5 pages on-line at http://www.ipm. ucdavis.edu/PMG/r734900211.html.
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Progress 10/01/03 to 09/30/04
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 the most commonly used management strategy to control soilborne diseases, nematodes, and weeds in high value fruits, nuts, vegetables, nursery crops, and ornamentals. Availability of methyl bromide was restricted in January 2001 to 50% of the amount used in the baseline year of 1991 and was further restricted to 30% of the baseline in 2003. It will be completely banned in 2005 except for uses with approved Critical Use Exemptions (CUE). CUEs are granted on a one-year basis. Strawberry, orchard and vineyard replant, and perennial nurseries have received Critical Use Exemptions for 2005 and have applied for CUEs for 2006. CUE applications for 2005 and 2006 for ornamental production are under evaluation by UNEP. U.S. growers of these high value crops are in dire need of
alternatives to the use of methyl bromide. The methyl bromide phase-out will result in an estimated 50% yield reduction in some crops and large economic losses, especially in strawberry, ornamental, and nursery crops, if effective alternatives are not found and CUEs are not granted. The availability or lack of acceptable alternatives will in turn, impact the supply and quality of these commodities to American consumers and the export market. Pre-plant soil fumigation with methyl bromide is used to control 'replant disorder,' meet regulatory requirements for clean propagative material, and control weeds and soilborne pathogens for many high value crops including grapes, stone fruit and nut trees, strawberries, nursery crops, and ornamentals. The phase out of methyl bromide highlights two major challenges. The first is to quickly find effective control measures that are economically feasible, fit current cropping systems, and are acceptable to environmental and regulatory agencies.
We are approaching this challenge by testing unregistered chemicals, novel applications of currently available chemicals, and new application technologies to deliver effective concentrations of materials to the target pests. Our team expertise in crop production, plant pathology, nematology, irrigation management, and soil chemistry, provides us the tools to address the biological, chemical, and engineering aspects of this project. Our current results indicate that this approach will meet the short-term to mid-term need. The second challenge is to increase our understanding of the pathogens and soil factors limiting crop production. A successful, long-term, integrated management approach requires a thorough understanding of biological, chemical, and physical soil factors, their interactions, and their spatial variability, and will include cultural, genetic, biological and chemical management strategies. Greenhouse, microplot, and field studies will generate new knowledge of these
interactions and their responses to currently available and newly developed management strategies. Innovative adaptations of drip irrigation technologies to develop a delivery system for biological and chemical management options offer the potential for greater flexibility and increased responsiveness to spatial variability. A better understanding of the causes of poor plant vigor in high value annual and perennial crops will lead to more science-based selections of management strategies. Effective, economic, environmentally acceptable pest and pathogen management strategies will contribute to the on-going productivity of high value annual and perennial cropping systems and the continued availability of clean planting stock from certified nurseries. The ultimate result will be a safe, dependable, high quality, and affordable food and flower supply for domestic and foreign markets, on- going productivity of crop production systems (many of them family farms), and protection of the
environment. Some of the knowledge gained may be specific to a particular crop production system or to California conditions, however, general principles regarding pathogen and pest management, technology and application methods, economics of alternative systems, irrigation and nutrient management, and precautions for providing environmental protection will be transferable to other crops and areas. Anticipated products from this project include new knowledge of, and diagnostic methodologies for, determining the causes of poor plant vigor in strawberry, ornamental, perennial, and nursery production systems in the absence of methyl bromide fumigation; new pest and pathogen management strategies that utilize new knowledge and novel application methods to effectively and economically control pests and pathogens while protecting the environment; field scale demonstrations of alternative management strategies, conducted in partnership with growers; growers who continue to be competitive in
the world market; and safe, dependable, high quality, affordable food and flower supplies. This work is relevant to producers of high value crops who currently use methyl bromide, Cooperative Extension personnel, pest control advisors, crop consultants, and scientists interested in the complex interactions between biological, physical, and chemical soil factors and their impact on crop growth, yield, and quality. The potential impact of this work is to substantially change soilborne pest and pathogen management for high value crops to strategies that are practical, economically feasible, and environmentally acceptable. 2. List the milestones (indicators of progress) from your Project Plan. 1. Etiology of soilborne diseases historically controlled by methyl bromide in ornamental, tree, and vine cropping systems more fully documented. a. Pathogens and pests from diseased fields isolated and identified. b. Pathogenicity of the isolated presumptive pathogens determined. 2. New
management strategies that can be used as alternatives to methyl bromide for strawberry, ornamental, nursery, tree, and vine cropping systems developed and evaluated. a. Chemical, genetic, biological, and cultural materials that can be used alone or as components of an integrated system developed and evaluated. b. New application technologies that result in a more uniform distribution of fumigant, less worker exposure, and reduced emissions compared to conventional shank injection developed and evaluated. 3. Promising alternatives to conventional shank-injection of methyl bromide have been integrated and evaluated in small field plots and demonstrated in field-scale trials under commercial conditions. 3. Milestones: Milestones: A. List the milestones (from the list in Question #2) that were scheduled to be addressed in FY 2004. How many milestones did you fully or substantially meet in FY 2004 and indicate which ones were not fully or substantially met, briefly explain why not,
and your plans to do so. Project Milestone #1a - Pathogen Isolation 1. Complete the etiological studies of a bacterial disease on calla lily. - Not done because of delay in getting APHIS permit for importation of pathogen. 2. Make pathogen isolations from ornamental crops. - Completed for Liatris, Myrtle, and Freesia 3. Investigate factors contributing to orchard and vineyard replant disorder and the impact of planting trees in vineyard soil and vines in orchard soil in microplots. - Trials initiated. 4. Determine etiology of peach replant disorder. - Scientist resigned before project was completed. Working cooperatively with G. Browne (Davis) to determine prunus replant etiology. Project Milestone #1b - Pathogenicity 1. Test possible pathogens for pathogenicity in ornamental crops. - Completed for Pythium and Phytophthora on Calla, Fusarium on Freesia, and Cylindrocladium on Myrtle. Project Milestone #2a - Management Strategies 1. Determine if Pythium populations from calla
lily fields are resistant to fungicides. - Completed. 2. Complete and publish field trials of effects of long-term fallow on tree replant. - Trials completed, publication under preparation, economic analysis in progress. 3. Complete and publish field trials of efficacy of drip-applied fumigants on tree growth and yield. - Trials completed, publication under preparation, economic analysis in progress. 4. Continue evaluation of nematode control and grapevine growth and yield one to six years after treatment (alternative fumigants, long term fallow, cover crops, resistant rootstocks) in vineyard replant trials. - Annual evaluations (plant growth, yield, nematode populations) completed. Trials are on-going. 5. Initiate microplot trials of combinations of chemical, biological, cultural, and genetic control strategies as alternatives to methyl bromide for perennial, nursery, and ornamental crops. - Three microplot trials were initiated. Evaluation of plant and nematode response to
treatments continue. 6. Initiate trial to evaluate potential post-plant nematode control measures in established perennial cropping systems, as an alternative to removing crop, fumigating with methyl bromide, and then replanting. - Trial was postponed until FY05. 7. Characterize bacteriophage and describe phage infection of A. tumefaciens cells. - Scientist resigned before project was completed. Project terminated. Project Milestone #2b - Application Technologies and Emission Reduction 1. Quantify relative emissions from sub-surface drip irrigation applied soil fumigants under a range of management practices (soil water content, surface seals, surface mulches, degraders). - Work delayed pending recruitment of vacant soil scientist position. Position was filled April 2004. Work is now underway with 2 grant proposals funded. 2. Evaluate adequacy of drip irrigation systems for delivery of fumigants - The irrigation distribution uniformity of 39 strawberry fields was measured,
management recommendations reported and 6 workshops presented. Project Milestone #3 - Field Trials and Commercial Demonstrations 1. Establish a trial with Mellano & Company for gladiolus production and control of Stromatinia dry rot. - Because of peculiarities of the cropping system, we instead established a trial with Mellano on myrtle for control of Cylindrocladium root rot. 2. Complete Calla Lily field trial. - Completed 3. Establish another cut flower trial with Hilltop Flowers. - Completed. 4. Carry out grower demonstration trials of methyl bromide alternatives for strawberries in cooperation with the CA Strawberry Commission. Write up a report summarizing 8 years of demonstration trials. - The 8th year of strawberry grower demonstration trials was carried out by the CA Strawberry Commission. Because of personnel changes, the CSC has not been able to consolidate and summarize the data. Alternative ways to summarize the data are being pursued. 5. Carry out strawberry water
use trials at Monterey Bay Academy. Complete quantification of irrigation crop coefficients for strawberries. Quantify grower irrigation management practices. - The 2nd year of strawberry water use trials at MBA is near completion with good results. Another site is being sought to continue the trials an additional year to verify climatic effects. 6. Evaluate no-till strawberry production with reuse of beds and drip application of fumigants. - 2nd trial completed. 7. Continue field trials of alternatives to methyl bromide for the rose nursery industry. - 2-year field trial at Jackson & Perkins completed, data summarized and presented at grower meetings. Plans initiated for additional trial. 8. Complete a 2-year tree nursery crop trial evaluating shank-injected alternatives to methyl bromide in a commercial field. - 2-year field trial at L. E. Cooke completed, data summarized and presented at grower meetings. 9. Evaluate efficacy of drip applied alternative fumigants in heavier
soils under commercial conditions for perennial and nursery cropping systems. Compare drip-applied with standard shank-injected fumigants for perennial replant and nursery crops on grower fields. - Trials initiated in 2 fields with finer textured soils. Evaluation of plant and nematode response to treatments will continue into FY06. 10. Initiate nut tree nursery trials and nut orchard replant trials in commercial fields evaluating shank-injected fumigants as alternatives to methyl bromide. - Two nursery and two orchard replant studies were initiated. Soil treatments were applied, initial nematode control data were collected. Evaluation of plant and nematode response to treatment will continue into FY05 and FY06. 11. Evaluate efficacy of drip application of registered fumigants on tree crops. - Two trials initiated, 4 trials are in progress, 2 trials completed. 12. Continue small-scale efficacy testing with bacteriophage for control of crown gall. - Small plot trial was
completed and results published. 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? FY2005 - Annual Milestones Project Milestone #1a - Pathogen Isolation 1. Pathogens from diseased materials from the various ornamental field trials isolated and identified. 2. Pests and pathogens involved in peach and grape replant disorder isolated, identified and evaluated for cross-specificity. Project Milestone #1b - Pathogenicity 1. Organisms isolated from ornamental fields tested for pathogenicity on various hosts according to Koch's postulates. Project Milestone #2a - Management Strategies 1. Rate studies of various methyl bromide alternatives conducted for cut flower production. 2. Various biocontrol agents for control of root disease on Calla evaluated in greenhouse trials. 3. Microplot trials initiated to evaluate
potential post-plant nematode control strategies for established perennial cropping systems. 4. Microplot trials initiated of combinations of chemical strategies as alternatives to methyl bromide for perennial, nursery, and ornamental crops. 5. Vineyard replant trials planted in 1998 and 1999 completed. 6. Long-term orchard replant fumigant small-plot field trials completed including data analysis and economic analysis. 7. Long-term fallow small-plot field trials for perennial replant completed including data analysis, economic analysis, and publication of results. 8. Nematode control and grapevine growth and yield three to six years after treatment (alternative fumigants, long term fallow, resistant rootstocks) evaluated in vineyard replant trials. 9. Field efficacy/phytotoxicity of 2-bromo ethanol (Agent 2B) evaluated. Project Milestone #2b - Application Technologies and Emission Reduction 1. Lab bench experiments conducted to evaluate important factors including soil types
and water content affecting fumigant degradation in soils. 2. Effects of fumigation methods evaluated in small field plots in combination with soil surface sealing techniques to reduce fumigant emissions of toxics and volatile organic compounds (VOCs). 3. Field and modeling study conducted to determine water application management practices that maximize lateral distribution of drip applied fumigants. Project Milestone #3 - Field Trials and Commercial Demonstrations 1. Almond nursery trial in commercial fields completed. 2. Efficacy of drip applied alternative fumigants in fine-textured soils evaluated under commercial conditions for perennial nursery cropping systems. 3. Drip-applied fumigant treatments compared with standard shank- injected fumigants for certified nursery crops on grower fields. 4. Alternative fumigants for nut tree replant evaluated in commercial fields. 5. 2-4 field trials conducted to determine fumigant (e.g., cis-1,3- dichloropropene,
trans-1,3-dichloropropene, and chloropicrin) distribution, dissipation, and degradation in soil profiles under drip and shank applications. 6. Additional cut flower trials established with new and emerging products. 7. New field trials of alternatives to methyl bromide for 2-year field nursery crops (roses and trees) initiated in commercial fields. 8. Third field trial of no-till strawberries initiated. FY2006 - Annual Milestones Project Milestone #1a - Pathogen Isolation 1. Pathogens from diseased materials isolated from the various ornamental field trials. Project Milestone #1b - Pathogenicity 1. Organisms isolated from ornamental fields tested for pathogenicity on various hosts according to Koch's postulates. Project Milestone #2a - Management Strategies 1. Rate studies conducted of various methyl bromide alternatives for cut flower production. 2. Microplot studies conducted of combinations of control measures as alternatives to methyl bromide for perennial and nursery
cropping systems. 3. Evaluations continued of post-plant nematicide use in perennial cropping systems in microplot trials initiated in FY05. 4. Additional microplot trials initiated of post-plant nematicides in perennial cropping systems. 5. Field efficacy/phytotoxicity evaluations of 2-bromo ethanol (Agent 2B) completed. 6. Vineyard replant trials planted in 2000 and 2001 completed. 7. Perennial crop yield and quality factors and nematode control 4 years after treatment (alternative fumigants and resistant rootstocks) evaluated in vineyard replant trials. Project Milestone #2b - Application Technologies and Emission Reduction 1. Column experiments conducted to study fumigant transport in soil. 2. Emission reductions studies expanded to other potential fumigants such as iodomethane. 3. Soil surface sealing techniques and other management practices that reduce fumigant emissions of toxics and VOCs tested in large field plots. 4. Additional field trials conducted in different
soil types and at different seasons to study fumigant fate in soils under drip and shank applications, and in combination with tarps. Project Milestone #3 - Field Trials and Commercial Demonstrations 1. Almond and walnut nursery trials in commercial fields completed. 2. Third field trial of no-till strawberries completed. 3. Interim evaluations conducted for 2-year nursery crop trials in commercial fields initiated in FY05. 4. Interim evaluations conducted for orchard replant trials in commercial fields initiated in FY04. 5. Evaluation of efficacy of drip applied alternative fumigants in fine- textured soils under commercial conditions for perennial nursery cropping systems continued. 6. Establish new cut flower trials with new and emerging products. FY2007 - Annual Milestones Project Milestone #1a - Pathogen Isolation 1. Pathogens from diseased materials isolated from the various ornamental field trials. Project Milestone #1b - Pathogenicity 1. Organisms isolated from
ornamental fields tested for pathogenicity on various hosts according to Koch's postulates. Project Milestone #2a - Management Strategies 1. Evaluations conducted of on-going microplot trials of post-plant alternatives to methyl bromide for nursery perennial cropping systems. 2. Rate studies conducted of various methyl bromide alternatives for cut flower production. 3. Establish additional microplot trials with new and emerging products. 4. Evaluation of post-plant nematicides for perennial nursery and orchard/vineyard production systems continued. 5. Perennial crop yield and quality factors and nematode control 5 years after treatment evaluated in vineyard replant trials. Project Milestone #2b - Application Technologies and Emissions Reductions 1. Mass balance approach used to evaluate the fate of fumigants after applying to soils. 2. Fumigant distribution, dissipation, and emissions data is used to develop or validate models of fumigant transport and fate. 2. Findings on
fumigant fate and application methods, as well as emission data, analyzed and published. Project Milestone #3 - Field Trials and Commercial Demonstrations 1. 2-year nursery crop trials that were initiated in commercial field nurseries in FY05 harvested. 2. On-going evaluations conducted for orchard replant trials in commercial fields initiated in FY04. 3. Soil surface sealing techniques and other management practices that reduce fumigant emissions of toxics and VOCs demonstrated in large field plots. 4. Additional cut flower trials established with new and emerging products. 5. Large field trial of no-till strawberries conducted. 4. What were the most significant accomplishments this past year? A. Tree and vine growers will likely lose productivity when methyl bromide is phased out between now and 2005 unless alternatives are found to control soil pests and reduce the effects of the "replant syndrome." Scientists at the USDA ARS SJVASC, in collaboration with Drs. Westerdahl and
McKenry of the University of California with support provided by Tri- Cal (commercial methyl bromide fumigation), numerous chemical companies (materials), and Sunridge Nursery (grape plants)tested several methyl bromide alternatives in replanted peach and plum orchards and vineyards in a series of field trials located at the SJVASC research station and in growers' fields in Dinuba, CA. Emulsified formulations of alternative fumigants 1,3 dichloropropene (1,3-D) and chloropicrin applied through subsurface drip irrigation systems produced tree growth and yield equal to methyl bromide; and control of plant parasitic nematodes in vineyard replant plots treated with drip-applied 1,3-D or shank-injected iodomethane was comparable to control achieved by methyl bromide after 6 growing seasons. Research will provide growers an alternative soil treatment in sandy loam soils that provides control similar to that achieved with methyl bromide. B. Other significant accomplishment(s), if any.
Continued production of the calla rhizome crop is dependent on finding a methyl bromide alternative. Dr. J. Gerik of the SJVASC, in collaboration with Golden State Bulb growers, evaluated seven different chemical combinations for weed and disease control in a pathogen intense field near Marina, CA. Treatments containing chloropicrin resulted in per acre yields comparable to those the grower obtained with his standard methyl bromide + chloropicrin fumigation. These alternative treatments have the potential to insure the continued production of calla lily rhizomes in the absence of methyl bromide and have resulted in calla lily rhizome growers using drip-applied fumigants on a portion of their crop. Although furfural has been shown to be a nematicide, little is known about its pathogen and weed control activity for use as an alternative to methyl bromide in field grown cut flowers. Dr. J. Gerik of the SJVASC, in collaboration with Dramm & Echter compared furfural, with and without
metham sodium, with iodomethane + chloropicrin and 1, 3 dichloropropene + chloropicrin in a field trial located in Encinitas, CA. Results show that furfural alone has little or no weed or pathogen control activity. This work documents that furfural is not a technically feasible alternative to methyl bromide for weed or pathogen control in cut flower production systems. Tree and rose nurseries, grown in the open field for 2-years, commonly use methyl bromide as a preplant soil fumigant to control soilborne pathogens, pests, and weeds and to comply with California regulations governing certified nurseries. In field trials conducted by Drs. Schneider, Gerik, and Trout, of the Water Management Research Unit at the SJVASC in Parlier, CA, alternative fumigants were applied by shank injection (tarped and untarped) and through drip irrigation in commercial tree and rose nurseries located in Visalia, CA (L.E Cooke Inc) and Wasco, CA (Jackson & Perkins Roses) with support from Tri-Cal
(commercial fumigation of all of the shank-injected materials), numerous chemical companies (materials) and L.E. Cooke and Jackson & Perkins (plants and labor). Several of the treatments, including 1,3-dichloropropene + chloropicrin and iodomethane +chloropicrin gave control, in sandy loam soils, of plant parasitic nematodes similar to methyl bromide down to a soil depth of five feet (150 cm) at the time of planting, resulted in soil nematode populations similar to methyl bromide after one growing season, and when tarped, resulted in the harvest of nematode-free two- year crops (as required by the clean propagative material regulations) that were similar in quality to crops grown in methyl bromide treated soil. This work could lead to California Department of Food and Agriculture approving new soil treatment practices for use in certified nurseries. Effective and efficient drip application of fumigants depends on uniform distribution of the fumigants and water through the drip
irrigation system. Irrigation distribution uniformity was measured by Dr. T. Trout of the SJVASC on 39 strawberry fields throughout the strawberry growing regions of California. Distribution uniformity varied from 45% to 93% and averaged 81% (a value that is disappointingly low for a precision system that can achieve over 90% uniformity) which results in a need for one-quarter additional water (or drip applied fumigant) to achieve the target amount on the drier areas of the field. This work identified problems related to improper design (beds too long), equipment (connector spaghetti tubing too small), and management (non-uniformly set valves). These results and recommendations were presented to strawberry growers in 4 irrigation workshops and will result in improvements in strawberry irrigation and drip fumigation. C. Significant activities that support special target populations. Several of the field demonstrations of methyl bromide alternatives have been carried out on fields
of small and minority (Hispanic) strawberry growers. 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). The USDA ARS SJVASC WMR's Methyl Bromide Research Team received more than $150,000 in funding from competitive grants, grower groups, and methyl bromide alternatives manufacturers, in addition to significant in- kind contributions of plants, land, labor, and chemical products. Four nut tree nursery and two nut orchard replant trials were initiated in commercial fields as part of a large team project including Drs. G. Browne (ARS Davis, CA), S. Schneider and T. Trout (both ARS Parlier, CA), and B. Lampinen and A. Shrestha (both UC Davis). Trials are located at Burchell Nursery, Brights Nursery, Sierra Gold Nursery, Dave Wilson Nursery, and Agriland. Bags containing weed seed, fungal pathogens, and
plant parasitic nematodes were buried at 6, 12, 24, and 36 inch soil depths prior to fumigation. Control of these pests and pathogens by tarped, shank-injected 1,3-D (Telone II), iodomethane + chloropicrin (Midas), and 1,3-D + chloropicrin (Telone C35) was comparable to methyl bromide at all depths in coarse-textured soils, but control of fungi and weed seed was not as good as methyl bromide at the deeper soil depths in finer-textured soils. These trials are on-going. The effects of 1, 2, and 3 years of dry fallow were tested on peaches, plums, and grapes. Peaches, plums, and grapes re-planted in the plots in 2000, are in their 5th year of growth, and 2nd or 3rd year of production. One year of fallow increased yields in all stonefruit trials by 10 to 20%. Treating tree stumps with systemic herbicide (Roundup) did not increase growth or yield compared to one year fallow in one trial. In both peaches and plums, each additional year of fallow increased growth and yield with 3 years
of fallow giving similar yields to that produced with methyl bromide fumigation. In the grape trial, after 4 years of growth, vine trunk diameters in plots following 3 years fallow were comparable in size to vines grown in methyl bromide treated plots for all three scion/rootstock combinations tested. Vines grown in untreated plots and plots following a 1 year fallow had significantly smaller trunk diameters than vines grown in methyl bromide treated plots for two of the three scion/rootstock combinations tested. In 6 field trials with peaches or plums, drip-applied 1,3- dichloropropene+ chloropicrin (InLine) produced growth and yields equivalent to tarped methyl bromide fumigation. In field fumigation trials on plums, drip applied chloropicrin produced tree growth that exceeded methyl bromide. Methyl bromide increase yields compared to no fumigation in all trials and years, with the increase ranging from 10% to over 100%. In 4 and 5 year old peaches, the relative yield effects
of the fumigation treatments decreased with tree maturity. These trials will be completed in 2004 and the economics of the alternatives will be analyzed. In a vineyard replant trial, planted in spring 2001 following the removal of an 85-year-old vineyard in the fall of 2000, the plant parasitic nematode populations in plots treated with iodomethane + chloropicrin, propargyl bromide, or InLine (drip-applied 1,3- dichloropropene + chloropicrin) were not significantly different after 3 growing seasons with a susceptible grape variety from populations in plots treated with methyl bromide. Plots treated with sodium azide or an herbicidal-rate of metam sodium supported nematode populations that were not significantly different from the untreated control plots after 3 growing seasons with a susceptible grape variety. Nematode control in plots treated with drip-applied chloropicrin was intermediate in efficacy; not as poor as untreated, but not as good as methyl bromide. These trials
are on-going. A combination vineyard replant/grapevine nursery trial, planted in 2003 in a field from which 60+year old grapevines were removed, is on-going. Treatments, including InLine (drip-applied 1,3-dichloropropene + chloropicrin) , Midas (iodomethane + chloropicrin), and sodium azide killed plant parasitic nematodes to a depth of five feet at the time of planting. Strawberry growers consume time, energy, water, and money preparing a strawberry field for the following year's strawberry planting. With drip fumigation, these costs could be reduced by reusing the previous strawberry beds. A no-till study of strawberry was initiated in 2001 in which strawberries are replanted on the same planting beds in consecutive years following removal of the previous plants and tarp, replacement of the existing drip tape and tarp, and drip fumigation. This process reduces production costs by over $600 per acre, reduces water use, and reduces plant-back time (and thus extends harvest time of
the previous crop) by 2 to 3 weeks. Results from the field trial in progress at Salinas showed no yield loss with bed reuse and current year yields show no yield decline for third year use of the same beds. This trial will be repeated. 5. Describe the major accomplishments over the life of the project, including their predicted or actual impact. All accomplishments are linked to Component I of the Action Plan for National Research Program 308 - Alternatives to Methyl Bromide. Project Milestone #1a - Pathogen Isolation Project Milestone #1b - Pathogenicity Project Milestone #2a - Management Strategies Import and manufacture of methyl bromide is being phased out for non- quarantine uses, resulting in a need for effective fumigants for some crop and pest combinations in the near term. A multi-agency (ARS, Univ. of CA, and Univ. of FL) and multi-state (CA and FL) effort to determine the efficacy of propargyl bromide as a soil fumigant was carried out by 14 scientists from 6 locations
(T. Trout, S. Schneider, H. Ajwa, M. Schutter USDA-ARS, Fresno, CA; F. Martin, USDA-ARS, Salinas, CA; K. Subbarao, S. Fennimore, Univ. CA, Salinas, CA; G. Browne, USDA-ARS, Davis, CA; B. Westerdahl, C. Elmore, U.C. Davis; C. Winterbottom, California Strawberry Commission, Watsonville, CA; E. Rosskopf, USDA-ARS, Ft. Pierce, FL; J. Noling, Univ. of Florida, Lake Albert, FL; J. Norton, USDA IR-4 Methyl Bromide Alternatives Program, FL) with USDA funding. The studies on tomato, strawberry, carrot, fruit trees, grape vines, and ornamentals determined that propargyl bromide is efficacious against most pests including nematodes, diseases, and weeds at rates above 100 pounds per acre, which is about 1/3 the current methyl bromide rate, and generally resulted in good plant growth and yield, although some phytotoxicity was noted in two trials. These coordinated studies indicate that propargyl bromide can be an efficacious replacement for methyl bromide. Determined the dose response in
strawberry fields of several diseases and weed seeds to 1,3-dichlorpropene, chloropicrin, iodomethane, and propargyl bromide. Determined that one-to-three year fallow periods after removal of a mature vineyard, significantly reduced populations at the time of planting of rootknot nematode down to a depth of 4 feet, but significantly reduced populations of citrus nematode only in the top 12 inches. Determined iodomethane to be equal to methyl bromide in control of peach replant disorder in collaboration with Dr. J. Sims, UC, Riverside. Registration of this methyl bromide alternative is actively underway in the private sector. Project Milestone #2b - Application Technologies and Emissions Reductions Effective drip application of fumigants depends upon delivering the fumigants to the target soil zone and computer models are useful to evaluate management practices to enable precision placement of the water and fumigants. Dr. T. Trout, SJVASC, collected field data at the SJVASC to
validate a two-dimensional soil water flow model for conditions of drip irrigation in collaboration with Todd Scaggs, ARS-Riverside. Hydrus 2-D was able to model the collected data very well using only soil particle size data to determine hydraulic parameters. This research will be used to determine management practices that maximize horizontal water movement and drip fumigant distribution from drip lines. Measured fumigant distributions in the soil following application with irrigation water through drip irrigation systems, determined that fumigant distribution improved with increasing water application, and recommended drip application fumigation practices. Determined the optimum parameters to apply soluble formulations of 1,3- dichloropropene in combination with chloropicrin and methylisothiocyanate by drip application. Project Milestone #3 - Field Trials and Commercial Demonstrations Tree, vine, and rose nurseries commonly use methyl bromide as a preplant soil fumigant to
control soilborne pathogens, pests, and weeds in compliance with California regulations governing certified nurseries and will need acceptable alternatives to methyl bromide. In field trials conducted by Drs. Schneider, Gerik, and Trout, all of the Water Management Research Unit at the SJVASC in Parlier, CA, alternative fumigants were applied by shank injection (tarped and untarped) and through drip irrigation in commercial tree, vine, and rose nurseries located in Visalia, CA (L.E Cooke Inc) and Wasco, CA (Jackson & Perkins Roses) with support from Tri-Cal (commercial fumigation of all of the shank-injected materials), numerous chemical companies (materials) and L. E. Cooke, Jackson & Perkins, and Sunridge Nursery (plants). Several of the treatments, including 1,3-dichloropropene, chloropicrin, and iodomethane gave control of plant parasitic nematodes similar to methyl bromide down to a soil depth of five feet (150 cm), resulted in soil nematode populations similar to methyl
bromide after one growing season, and when tarped, resulted in the harvest of nematode-free one-year crops (as required by the clean propagative material regulations) that were similar in quality to crops grown in methyl bromide treated soil. This work could lead to California Department of Food and Agriculture approving new soil treatment practices for use in certified nurseries. Growers of ornamental crops will likely encounter production losses after the methyl bromide phase out in 2005 unless alternatives are found. Dr. J. Gerik, SJVASC, established methyl bromide alternative field trials for snapdragon, liatris and Dutch iris production in Oxnard, CA, and Carpinteria, CA with Pyramid Flowers, Hilltop Flowers, and Brand Flowers and the support of numerous chemical companies (materials). We have shown that several alternatives have significantly reduced populations of pathogens and weeds. These results indicate that methyl bromide alternatives for cut flower production do exist.
Use of 1,3-D (Telone) in California is limited by state 'township cap' regulations. Dr. Trout analyzed existing state pesticide use databases to determine fumigant use trends and the likely impact of township caps on adoption of alternative fumigants that contain this chemical. The analysis showed severe impacts on certain commodities and geographic areas. These data are being used by EPA and Parties to the Montreal Protocol to provide methyl bromide use exemptions where 1,3-D is the only viable alternative. 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? The USDA ARS SJVASC WMR's Methyl Bromide Research Team received a USDA- ARS Superior Technology Transfer Award for demonstrating and extending research on alternative fumigants, application
techniques and cultural practices that allow growers to maintain current production levels without the use of methyl bromide. As a result of the transfer of our research results, calla lily rhizome growers are now using drip-applied soil fumigants on a portion of their crop. The 4th annual Field Day for Methyl Bromide Alternatives for CA Tree, Vine, and Nursery Crops featuring tours of our field trials located on the SJVASC was conducted at the end of last field season (attendance > 40) . The 7th annual meeting of the Advisory Group for Methyl Bromide Alternatives for CA Perennial Crops was held in January for growers, industry representatives, and scientists, to review the issues and to recommend research priorities (attendance > 30, minutes and handouts emailed to 100+ people). Numerous individual tours of our field trials have been arranged for growers, industry, govt. agencies (U.S. EPA, USDA) university (including Cooperative Extension), and ARS scientists, and the press. A
monthly Brown Bag Lunch Seminar series continues to foster information exchange between SJVASC and the University of California's Kearney Agricultural Center. A 5-day tour of our research trials and commercial fields was conducted for the United Nations Environmental Programme Methyl Bromide Technical Options Committee (MBTOC) in Nov. 2003. A California Strawberry Commission "Pink Sheet" on Drip Fumigation of Strawberries was published and presented at a series of grower workshops. A chapter on Drip Fumigation for the revised manual Pest Management Guidelines for Strawberries was prepared. Six grower workshops (4 in English, 2 in Spanish) on Drip Irrigation of Strawberries were presented. The California Association of Nurserymen - Deciduous Growers met at the SJVASC. Presentations were given on drip fumigation, update on the status of methyl bromide alternatives, and the Critical Use Exemption process and results. Oral presentations on Methyl Bromide Alternatives for perennial crops
were presented to over 800 attendees in several forums (Blue Diamond Annual Meeting; Pesticide Applicators Professional Association seminar; CA Almond Board Research and Environmental committee meetings; Calif. Tree Fruit Agreement IPM seminar). Presentations of strawberry irrigation and tillage practices were presented at two field days (Monterey Bay Academy and USDA Spence Farm). 7. List your most important publications in the popular press and presentations to organizations and articles written about your work (NOTE: Do not list your peer-reviewed publications here; list them under "Publications"). Presentations: Schneider, S., T. Trout, and J. Gerik. Alternatives to Methyl Bromide for Perennial Crop Field Nurseries - Results & Proposed New Work. California Fruit Tree, Nut Tree, and Grapevine Improvement Advisory Board. Sacramento, CA. April, 2004. Schneider, S. Critical Use Exemptions - Status and Schedule. California Fruit Tree, Nut Tree, and Grapevine Improvement Advisory
Board. Sacramento, CA. April, 2004. Schneider, S., T. Trout, J. Gerik, H. Ajwa, and J. Sims. Alternatives to Methyl Bromide for Field Nursery Production Systems - a Research Update. Garden Rose Council. Davis, CA. May, 2004. Schneider, S. ARS Research on Alternatives to Soil Fumigation with Methyl Bromide - The California Experience. US/Canada Methyl Bromide Working Group. Windsor, Ontario, Canada. May, 2004. Schneider, S. Critical Use Exemptions. California Association of Nurserymen - Deciduous Growers. Parlier, CA. June, 2004. Schneider S., G. Browne, B. Lampinen, and A. Shrestha. Alternative Preplant Fumigation Strategies for Nut Crop Nurseries and Production Orchards. California Association of Nurserymen - Deciduous Growers. Parlier, CA. June, 2004. Schneider, S., T. Trout, S. Gao, and H. Ajwa. The Potential of Drip Fumigation as a Part of the Nursery Cropping System. California Association of Nurserymen -Deciduous Growers. Parlier, CA. June, 2004. Trout, T. and
H. Ajwa. Drip Fumigation. International Society for Horticultural Science. 4th International Symposium on Irrigation of Horticultural Crops. Davis, CA. Sept. 2003. Trout, T., Methyl Bromide Alternatives for California. PAPA Seminar, Visalia, CA. Dec 3, 2003. Trout, T., Methyl Bromide Alternatives for California. Blue Diamond Annual Meeting, Modesto, CA. Nov 21, 2003. 7. List your most important publications in the popular press and presentations to organizations and articles written about your work. Popular Press Articles written by us: Trout, T. Fumigant Use in California. CA Tree Fruit Agreement Research Report. Oct 8, 2003. Trout, T. Methyl Bromide Replacement Update. California Farmer. Nov 2003. Popular Press Articles written about us: Methyl Bromide Alternative Projects bear Diverse Fruit: Cultural control and etiology of replant disorder of Prunus spp. Sustainable Agriculture. 15(2) Summer 2003. Farm Pest Assassin Sought. Fresno Bee, Sept 3, 2003 (coverage of field
day). Effectiveness of Drip Fumigation Examined in Strawberry Fields. Ag. Alert, Oct 1, 2003. Compounds Zap Grapevine Worm Enemy. Western Farm Press, Dec 6, 2003. New fumigants for Seedling Grapevines. OzonAction Newletter 46:8. United Nations Environmental Programme Division of Technology, Industry and Economics (UNEP DTIE). Dec. 2003. Trout, T. and H. Ajwa. Soil Fumigants through Drip Irrigation Systems. New Ag International. Dec. 2003.
Impacts
(N/A)
Publications
- AJWA, H.A., FENNIMORE, S., KABIR, Z., DUNIWAY, J., BROWNE, G.T., TROUT, T. J., GOODHUE, R., GUERRERO, L. STRAWBERRY YIELD UNDER REDUCED APPLICATION RATES OF CHLOROPICRIN AND INLINE IN COMBINATION WITH METAM SODIUM AND VIF.. INTERNATIONAL CONFERENCE ON METHYL BROMIDE ALTERNATIVES AND EMISSIONS REDUCTIONS. 2003.
- SCHNEIDER, S.M., TROUT, T.J., BROWNE, G.T., AJWA, H.A., SIMS, J. VINEYARD REPLANT FIELD TRIALS. INTERNATIONAL CONFERENCE ON METHYL BROMIDE ALTERNATIVES AND EMISSIONS REDUCTIONS. 2003.
- SCHNEIDER, S.M., TROUT, T.J., GERIK, J.S., RAMMING, D.W., AJWA, H.A. METHYL BROMIDE ALTERNATIVES FOR PERENNIAL NURSERIES - 1ST AND 2ND YEAR PERFORMANCE.. INTERNATIONAL CONFERENCE ON METHYL BROMIDE ALTERNATIVES AND EMISSIONS REDUCTIONS. 2003.
- Han, Schufeng, Schneider, Sally M., Evans, Robert G. 2003. EVALUATING cokriging for imporving soil nutrient sampling efficiency. Transactions of the ASAE, Vol. 46(3):845-849. American Society of Agricultural Engineers ISSN 0001-2351.
- SHUFENG, H., SCHNEIDER, S.M., EVANS, R.G., DAVENPORT, J.R. BLOCK ESTIMATING OF SPATIAL YIELD DATA AND ITS UNCERTAINTY. PRECISION AGRICULTURE, 5, 73-84, 2004.
- TROUT, T.J., SCHNEIDER, S.M., AJWA, H.A., GARTUNG, J.L. FUMIGATION AND FALLOWING EFFECTS ON REPLANT PROBLEMS IN CALIFORNIA PEACH.. INTERNATIONAL CONFERENCE ON METHYL BROMIDE ALTERNATIVES AND EMISSIONS REDUCTIONS. 2003.
- TROUT, T.J. IMPACT OF TOWNSHIP CAPS ON TELONE USE IN CALIFORNIA.. INTERNATIONAL CONFERENCE ON METHYL BROMIDE ALTERNATIVES AND EMISSIONS REDUCTIONS. 2003.
- TROUT, T.J. FUMIGANT USE IN CALIFORNIA.. INTERNATIONAL CONFERENCE ON METHYL BROMIDE ALTERNATIVES AND EMISSIONS REDUCTIONS. 2003.
- TROUT, T.J., AJWA, H.A. APPLICATION OF FUMIGANTS THROUGH MICROIRRIGATION SYSTEMS.. ASAE ANNUAL INTERNATIONAL MEETING. 2003. PAPER #032021.
- AJWA, H.A., NELSON, S.D., TROUT, T.J. WATER AND METHYL ISOTHIOCYANATE DISTRIBUTION IN SOIL AFTER DRIP FUMIGATION WITH METAM SODIUM.. INTERNATIONAL CONFERENCE ON METHYL BROMIDE ALTERNATIVES AND EMISSIONS REDUCTIONS. 2003.
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