Fusarium and fumonisin occurrence in Argentinian cool at different ear maturity stages

The distribution of Fusarium species (Liseola section) and fumonisins B-1, B-2, and B-3 (FB1, FB2, and FB3) in corn at the field stage to harvest time has been investigated. Corn samples were obtained from the 45th day after flowering to harvest stage, with 15 day intervals. A good correlation between fungal species and fumonisin contamination was observed. In particular, fumonisin contamination was higher in samples with fungal infection represented mainly by Fusarium moniliforme and Fusarium proliferatum, two well-known producers of fumonisins. Low levels of fumonisins were detected at the first and second samplings, when mainly Fusarium subglutinans, a fumonisin nonproducer species, was recorded. The three samplings after physiological maturity showed predominant F. moniliforme and F. proliferatum infection and a considerable contamination with fumonisins. In these samples the levels of FB1 averaged above 1 mu g/g and FB2 and FB3 levels showed similar values but lower than FB1 values. This is the first report of fumonisins in Argentinian corn at field stages.