Improved Environmental and Crop Safety by Modification of the Aspergillus flavus Population Structure

1. Optimize and expand use of biological control of aflatoxins based on atoxigenic strains of Aspergillus flavus in order to improve access, affordability, and areawide management. Sub-objective 1.1. Evaluate area-wide influences where atoxigenic biopesticides are widely used and develop strategies to increase cost-savings and efficacy based on area-wide effects. Sub-objective 1.2. Evaluate the potential to adapt hydropriming from seed technology to use with atoxigenic strain products to increase atoxigenic strain release under low humidity. Sub-objective 1.3. Advance biological control products based on atoxigenic strains of A. flavus with commercial field testing. Sub-objective 1.4. Improve access to atoxigenic strain biopesticides by assisting stakeholders to reduce costs of manufacture and distribution and expand biopesticide products while engaging USEPA in dialogue on biocontrol regulatory issues and public sector roles. 2. Develop an understanding of the distribution of Aspergillus flavus genetic haplotypes and vegetative compatibility groups worldwide in order to improve selection of biological control agents. Sub-objective 2.1. Identify A. flavus endemic in and adapted to target agroecosystems. Sub-objective 2.2. Determine utility of SSRs in tracking mechanisms and histories of divergences within A. flavus. Sub-objective 2.3. Develop an SSR database to support global efforts to delineate distributions of A. flavus genotypes and relationships among strains under investigation in diverse locations. 3. Improve understanding of development, evolution, and stability of populations of Aspergillus flavus, including phenomena occurring both within and between VCGs, in order to inform to inform optimization of long-term beneficial effects of atoxigenic strain biocontrol. Sub-objective 3.1. Determine the nature of clonal evolution in A. flavus with genomic analyses. Sub-objective 3.2. Assess mutation rate in an A. flavus genome during asexual reproduction in controlled laboratory evolution studies.