|Zitomer, Nicholas -|
|Zimeri, Anne Marie -|
Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: February 13, 2014
Publication Date: February 13, 2014
Repository URL: http://handle.nal.usda.gov/10113/58702
Citation: Baldwin, T.T., Zitomer, N.C., Mitchell, T.R., Zimeri, A., Bacon, C.W., Riley, R.T., Glenn, A.E. 2014. Maize seedling blight induced by Fusarium verticillioides: accumulation of fumonisin B1 in leaves without colonization of the leaves. Journal of Agricultural and Food Chemistry. 62:2118-2125. doi: 10.1021/jf5001106. Interpretive Summary: The fungus Fusarium verticillioides is a common pathogen of maize. The infected plant is often contaminated with mycotoxins produced by the fungus. Studies have concentrated on the most common mycotoxins, fumonisin B1 (FB1), FB2, and FB3. FB1 is the most toxic and has been implicated in a number of farm animal diseases and in some human diseases. Previous research demonstrated that FB1 is also a plant toxin contributing to maize seedling blight disease. In this study we thoroughly analyze plant tissue and soil samples to understand the relationship between fungal colonization of the plant and co-occurrence of the fumonisin mycotoxins in the plant during maize seedling infection. We conclude that a mechanism for fumonisin movement from the roots into the leaves requires the fungus, but actual colonization of those leaves by the fungus is not necessary. Further study will attempt to identify the unknown mechanism of fumonisin movement.
Technical Abstract: Fusarium verticillioides produces fumonisin mycotoxins during the colonization of maize, and fumonisin B1 (FB1) production is necessary for manifestation of maize seedling blight disease. The objective of this study was to assess the in planta occurrence of fumonisin, fungal colonization, and disease symptom development in seedlings grown from seed inoculated with F. verticillioides. Tissue and soil samples were analyzed to compare wild-type F. verticillioides against an aconidial mutant. Inoculation with either strain caused accumulation of FB1 in the first and second leaves, but the mutants were unable to colonize aerial tissues. FB1, FB2 and FB3 were detected in the soil and seedling roots, but only FB1 was detected in the leaves of any treatment. Our data suggest infection by F. verticillioides is necessary for accumulation of FB1 in leaves, but the mechanism for accumulation does not require colonization of the leaf.