2009 Annual Report 1a.Objectives (from AD-416) To develop, test, and demonstrate effective and practical field management techniques for pest nematode control with minimal air and water quality concerns in soil fumigation with methyl bromide alternatives. 1b.Approach (from AD-416) Surface barriers such as extremely low permeability plastic films will be used under field conditions to reduce fumigant emissions to the air. Soil amendments with natural organic materials such as animal manure or synthetic chemicals will be evaluated alone or in combination with the low permeability films to enhance fumigant decomposition thus reducing emission potential and protect air quality. Application of fumigants with irrigation systems will be tested in comparison with shank injection methods and potential for deep percolation and surface runoff will be evaluated. Impact of soil organic and inorganic amendments on air and water quality will also be measured. 3.Progress Report This SCA was created to support ARS research effort on methyl bromide alternatives with expertise from the University of California at Riverside. Soil fumigation is used in grape replant to control soil-borne nematodes and plant pathogens. New state and federal regulations also imposed strong limitations on reducing air and water quality risks when soil fumigants are used in the open field. Field trials are carried out in the central valley of California to measure air emissions of methyl bromide alternative chemicals. Techniques for reducing emissions are water seal and low permeability films. Soil moisture was also monitored to determine if any potential leaching of fumigant chemicals would occur. Additional field experiments are planned for the coming fall when new fumigation trials will be carried out. The project is monitored by regular conference calls between ARS and the university investigators on the project.