A. flavus and A. parasiticus, naturally-occurring soil fungi, can invade food and feed crops, contaminating them with aflatoxin. Aflatoxin is a human carcinogen produced by the fungi and is also toxic to pets, livestock, and wildlife. Researchers with the Agricultural Research Service have confirmed that Afla-Guard, a biological control used to thwart the growth of fungi on peanuts, can be used on corn as well.
Afla-Guard is composed of hulled barley coated with spores of a nontoxic strain of A. flavus. The nontoxic Aspergillus fungi successfully compete against the toxic species for the limited space and nutrients each needs to grow and thrive. In peanuts, Afla-Guard reduced aflatoxins by an average of 85% in farmers' stock peanuts and up to 97% in shelled, edible-grade peanuts. After a two year study, it was found that Afla-Guard was effective in reducing aflatoxin levels in corn, showing an overall reduction of 85%, when compared to control fields.