ARS | Publication request: Grain Yield and Fusarium Ear Rot of Maize Hybrids Developed From Lines With Varying Levels of Resistance

Submitted to: Maydica
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 1, 2009
Publication Date: July 15, 2009
Citation: Eller, M.S., Robertson-Hoyt, L., Payne, G., Holland, J.B. 2009. Grain Yield and Fusarium Ear Rot of Maize Hybrids Developed From Lines With Varying Levels of Resistance. Maydica. 53:231-237.

Interpretive Summary: Fusarium ear rot, caused by the fungus Fusarium verticillioides is common in the southern United States, and found in all U.S. maize growing regions. Affected grain often contains fumonisins, suspected carcinogens which cause disease in animals. In previous research, we identified inbred lines that had distinctly different levels of resistance to the disease. In this study, we tested the hypothesis that inbred lines with greater resistance to fumonisin contamination could be crossed to produce hybrids with greater ear rot resistance and greater resistance to yield loss under artificial inoculation with Fusarium spp. Our results disproved this hypothesis. There was no difference between hybrids created from lines with low and high levels of resistance. We believe that this was observed because of generally low levels of disease in the experiments. The hypothesis still may be true under higher levels of fungal infection.

Technical Abstract: Fusarium ear rot, caused by Fusarium verticillioides and other Fusarium spp. is found in all U.S. maize growing regions. Affected grain often contains carcinogenic mycotoxins called fumonisins. We tested the hypothesis that inbred lines with greater resistance to fumonisin contamination would produce hybrids with greater ear rot resistance and greater resistance to yield loss under artificial inoculation with Fusarium spp. Grain yield and Fusarium ear rot were measured under artificially inoculated and uninoculated conditions in two groups of hybrids created by topcrossing lines which exhibited either high or low levels of ear rot and fumonisin accumulation as inbreds per se in a previous study. Our results demonstrated that the hypothesis is not generally valid: the two groups of hybrids did not have significantly different ear rot or yield, perhaps because of generally low levels of ear rot observed in the testing environments.