Sources of Resistance to Fumonisin Accumulation in Grain and Fusarium Ear and Kernel Rot of Corn

Clements, M. J., Maragos, C. M., Pataky, J. K., and White, D. G. 2004. Sources of resistance to fumonisin accumulation in grain and Fusarium ear and kernel rot of corn. Phytopathology 94:251-260. Fumonisin is a group of homologous mycotoxins produced by several species of Fusarium. Fumonisin has been associated with Fusarium ear and kernel rot of corn (Zea mays) and several toxicoses of animals and humans. Corn inbreds with a high level of resistance to fumonisin production and accumulation in grain have not been identified. The objective of this study was to evaluate a genetically diverse collection of inbreds as potential sources of resistance to fumonisin production and accumulation in grain and Fusarium ear and kernel rot when crossed with a commercial “B73-type” line. F1 hybrids developed with the inbred FR1064 and 1,589 and 1,030 inbreds were evaluated in inoculated and naturally infected trials, respectively, in 2000. Thirty-five F1 hybrids with fumonisin concentration in grain of ≤5 µg/g in both trials were selected. Inbreds from which these 35 F1 hybrids were produced included yellow-, white-, and red-kernelled lines; flint and dent lines; and early- through late-maturing lines. In 2001, low fumonisin concentration in grain and low ear rot severity were associated with several of the F1 hybrids and their distinct F2, and backcross to FR1064 generations. This suggests that several dominant genes are involved in resistance and that alleles for resistance from these inbreds can be transferred to FR1064. A group of homologous mycotoxins known as fumonisin is produced by several species of Fusarium Link. Fumonisin is synthesized in corn (Zea mays L.) grain by Fusarium verticillioides (Sacc.) Nirenberg (Syn. = F. moniliforme J. Sheld.) and F. proliferatum (Matsushima) Nirenberg. These two species cause Fusarium ear and kernel rot of corn. Fumonisin is a causal agent