Submitted to: Plant Disease
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 25, 1997
Publication Date: N/A
Interpretive Summary: A fungus, Fusarium moniliforme, grows within corn plants and produces toxins that cause severe food safety problems. Poultry, swine and horses eating contaminated corn may develop deadly diseases. Methods must be developed to prevent these toxins in our food and feed supply. Some kinds of F. moniliforme, do not cause visible diseases on corn; this is referred to as a symptomless endophytic infection. Corn plants with this symptomless endophytic infection may still accumulate toxins which enter the food chain. This endophytic infection has a parallel in tall fescue grass where many resources were devoted to developing fungal-free fescue, but the fungus was later discovered to benefit plant growth by enhancing vigor, pest resistance, and stress tolerance. We do not know if removing the fungus from corn will be like fescue. The objective of this study was to determine the effects of fthe symptomless endophytic infection on the growth performance of corn plants. Growth of corn plants with and without F. moniliforme were analyzed for 28 days after planting. Researchers at the Russell Research Center determined that corn growth was superior for plants with the fungus than in those without it. These studies suggest that eliminating the fungus might reduce corn productivity. Thus, control methods that prevent the grow of F. moniliforme in corn plants must be augmented by management practices designed to increase plant growth offset by the fungus removal.
Technical Abstract: Kernels of corn, Zea mays, were artifically infected with a symptomless endophytic strain of the fungus, Fusarium moniliforme. Germination was monitored the first 6 days post planting (DPP) as coleoptile emergence. Seedling development, expressed as plant height, dry weight, shoot diameter and leaf length as well as in planta F. moniliforme distribution were analyzed weekly for 28 DPP. Seedling development, but not germination, wa affected by F. moniliforme infection. Growth of infected seedlings was less at 7 DPP, but equalled or exceeded non-infected seedlings by 28 DPP. Leaf initials were two-fold greater in infected than non-infected seedlings at 7 DPP. Another developmental modification was acceletated lignin deposition in stems of infected seedlings. F. moniliforme was isolated from most organs from the first until the last sampling, with the exception of never being isolated from the youngest leaves. Thus development and morphology of Z. mays seedlings were altered by a strain of F. moniliforme causing symptomless infection.