Breeding Maize for Resistance to Mycotoxins

Maize can host several fungi that produce mycotoxins.Despite decades of research, preventing the infection of maize kernels by toxigenic fungi remains a challenging problem. One approach to reducing mycotoxins in maize grain is to identify germplasm with increased resistance to fungal infection and lower levels of accumulated toxins. We review field and laboratory techniques that measure these two aspects of the disease and the application of these techniques to the identification of resistant maize genotypes and to the evaluation of quantitative inheritance of resistance to ear rot and mycotoxin accumulation. Sources of resistance to Fusarium verticillioides, Fusarium graminearum, and Aspergillus flavus have been identified and incorporated into public and private breeding programs. Recently described genes and quantitative trait loci providing resistance to fungal infection and their application to breeding for resistance to mycotoxin accumulation are reviewed. Genomic and transgenic approaches to preventing mycotoxin accumulation in maize also are discussed.