Research on the Aflatoxin Problem in Groundnut at ICRISAT

Aflatoxin contamination of groundnuts is a serious problem in most groundnut producing countries and as such is given high research priority at ICRISAT. Since 1979, we have concentrated on selecting cultivars resistant to seed invasion and colonization by toxigenic strains of Aspergillus flavus, and/or to aflatoxin production. Resistance to invasion and colonization by A. flavus of rehydrated, mature seed has been found, and confirmed, in some cultivars. Such resistance is of value in the event of the stored groundnuts absorbing sufficient moisture to permit fungal growth. We have also screened cultivars for field resistance to invasion of seeds by A. flavus, both under natural conditions and with inoculum of the fungus added to the soil in the pod zone. Some cultivars with resistance to seed colonization also showed resistance to field invasion by A. flavus. None of the cultivars tested has yet shown complete resistance to aflatoxin production, but significant differences occurred in amounts of aflatoxin produced in seeds inoculated with a toxigenic strain of A. flavus