A. flavus L-strainA. flavus L-strain.

The biocontrol strategy employs a mechanism called “competitive exclusion.” This is made possible by the presence in nature of A. flavus populations, not only of “toxigenic” types (strains), which produce copious amounts of aflatoxin, but also “atoxigenic” strains, which lack this capacity. In order for the strategy to work, it is necessary to identify and successfully introduce harmless atoxigenic strains that show a large competitive advantage over the dangerous ones. In the resulting biological struggle, the good strains of A. flavus virtually eliminate their highly toxic relatives and thereby reduce aflatoxin contamination.