Submitted to: Journal of Food Protection
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/17/1999
Publication Date: N/A
Interpretive Summary: Serious, and often fatal, health problems develop in animals and humans eating corn products contaminated with toxins produced by Fusarium moniliforme, a fungus. We need to develop methods to restrict the growth of this fungus because no fungicide, resistant cultivar, or cultural practice is available that can effectively control F. moniliforme growth in ncorn. The objective of our studies was to determine whether another fungus, Trichoderma viride, isolated from corn root segments would be an effective biocontrol agent for F. moniliforme growth and/or production of FB1. Researchers at Russell Research Center discovered that T. viride reduced F. moniliforme growth by 46% after 6 days and by 90% after 14 days and FB1 production by greater than 80%. Thus, T. viride may be useful in biological control as a pre-harvest agent to inhibit F. moniliforme growth during kernel development and/or as a post-harvest agent to suppress FB1 accumulation when kernels are dried inadequately
Technical Abstract: Biocontrol activity against Fusarium moniliforme was analyzed for a Trichoderma viride strain isolated from root segments of corn plants grown in piedmont Georgia. The isolate suppressed radial extension of F. moniliforme colonies during co-cultivation on potato dextrose agar and fumonisin B2 (FB1) production during incubation of both fungi on corn kernels. T. viride decreased radial extension of F. moniliforme by 46% after 6 days and by 90% after 14 days. Furthermore, the colony diameter of F. moniliforme was less at 14 days than at 5 days, suggesting that F. moniliforme mycelia were undergoing lysis. FB1 production by F. moniliforme on corn kernels decreased by >80% when both organisms were inoculated the same day onto corn kernels, and by >70% when inoculation of T. viride was delayed by 7 days after F. moniliforme inoculation. These results are the first to demonstrate that T. viride can suppress FB1 production by F. moniliforme, thereby functioning to control mycotoxin production. Thus, this isolate may be useful in biological control as a pre-harvest agent to inhibit F. moniliforme growth during kernel development and/or as a post-harvest agent to suppress FB1 accumulation when kernels are dried inadequately.