ECOLOGICAL BASIS FOR AFLATOXIN REDUCTION THROUGH CROP MANAGEMENT AND BIOLOGICAL CONTROL

(1) Improve manufacture and formulation of ATOX for management of aflatoxin contamination. Specifically address problems in applying atoxigenic strain technology to commercial practice and optimize formulation for successful delivery of biocontrol agents. (2) Characterize influences of agronomic practices (tillage, irrigation, crop rotation, application strategy) on biocontrol of aflatoxin contamination and optimize field use of ATOX on a commercial scale. (3) Develop an epidemiological model to explain formation of aflatoxins in Texas and Arizona, with emphasis on the contamination after crop maturation (the second phase of contamination). (4) Characterize the major vegetative compatibility groups (VCGs) associated with Arizona and Texas agriculture and associated niches, and test geographical and niche specialization in order to improve understanding of the etiology of contamination and selection of ATOX with improved competitive ability in target crops/areas. Develop both a single nucleotide polymorphism (SNP) database and molecular tracking techniques useful in characterizing the composition of A. flavus communities, at both the strain and VCG level on crops and in the environment. (5) Characterize A. flavus responses to varying environments and ecological niches (including animal and plant hosts) to assess fungal adaptations leading to niche competence and to facilitate selection of elite biocontrol strains and development of management practices. Data will be used to contribute to select elite biocontrol strains with improved efficacy and safety.