Wednesday, May 2, 2018 at 12:20pm
Graduate Student Exit Seminar, PPPMB, Cornell University
Aflatoxin is the most potent mycotoxin known—it is the most tightly regulated mycotoxin by the U.S. Food and Drug Administration. Aflatoxin is produced by a few species in the genus Aspergillus (section Flavi), and contaminates maize, peanuts, cottonseed, tree nuts, and other seed crops. The long-term goal of my research is to reduce aflatoxin contamination in food by understanding the significance of aflatoxin in the ecology of Aspergillus flavus, the most common aflatoxin-producing species. My overarching hypothesis is that aflatoxin confers a fitness advantage to A. flavus under some conditions, but not others. More specifically, variation in selection for or against aflatoxin under different conditions maintains polymorphism in aflatoxin production in A. flavus, and explains the prevalence of naturally occurring A. flavus individuals that do not produce aflatoxin (referred to hereafter as nontoxigenic isolates). My goal, therefore, is to understand the ecological factors that select for and against aflatoxin production in agricultural systems. Ultimately I hope to get a better understanding of the ecological significance of A. flavus secondary metabolism in general, and may contribute to the improvement of biological control efforts for reducing aflatoxin contamination of agricultural products.