Controlling Aflatoxin and Fumonisin in Maize by Crop Management

Maize is a vital food and feed grain worldwide. Aflatoxin and fumonisin, mycotoxins produced primarily by the fungi Aspergillus flavus and Aspergillus parasiticus Speare, and Fusarium moniliforme J. Sheld, respectively, are very potent carcinogens in both humans and livestock and can readily contaminate maize grain in the field and in storage. Stress on developing maize, particularly during reproductive growth, facilitates infection by the fungi, production of mycotoxins and contamination of the grain. Drought, excessive heat, inadequate plant nutrition, insect feeding on developing kernels, weeds, excessive plant populations, and other plant diseases can produce plant stress and facilitate the infection of maize grain by mycotoxin producing fungi. Timely planting of adapted hybrids, proper plant nutrition, irrigation, and insect control either by insecticides or the use of transgenic hybrids all assist in curbing mycotoxin contamination. Production practices that produce high yields are basically the same ones that help control mycotoxins. Care must also be exercised in harvesting and handling grain in transport and storage to reduce kernel breakage and prevent contamination. Harvesting early and artificial drying helps reduce the incidence of mycotoxins as well as preventing kernel breakage and stored‐grain insect infestations.