Infection and fumonisin production by Fusarium verticillioides in developing maize kernels

Fusarium ear rot and fumonisin contamination are serious problems for maize growers, particularly in the southeastern United States. The lack of maize genotypes highly resistant to infection by Fusarium verticillioides or to fumonisin contamination emphasizes the need for management strategies to prevent contamination by this mycotoxin. Information on the initial appearance of infection and fumonisin contamination of kernels and their increase over time is needed to determine if early harvest may be an appropriate control strategy. Maize ears from replicated studies at two locations in eastern North Carolina were harvested weekly, starting 2 weeks after pollination and continuing for 14 weeks. The percentage of kernels infected with E verticillioides and the fumonisin contamination in the harvested samples were determined. Kernel infection by F. verticillioides and fumonisin contamination appeared as kernels neared physiological maturity and increased up to the average harvest date for maize in North Carolina. Beyond this date, the concentrations of fumonisin fluctuated. Under years conducive for fumonisin contamination. early harvest (greater than 25% grain moisture) may help reduce the level of contamination.