Incidência fúngica e contaminações por micotoxinas em grãos de híbridos comerciais de milho em função da umidade de colheita

Abstract

The objective of this work was to evaluate the incidence of Aspergillus, Fusarium and Penicillium fungi, and the contaminations with mycotoxins in grains of five corn commercial hybrids due to harvest humidity. The work was conducted in Astorga, Paraná State, during the autumn/fall harvest of 2007 and the summer harvest of 2007/2008. The corn grain samples were collected in five distinguished periods and also in five replications, subjected to humidity content determination at an oven heated to 103 ± 1°C for 72h. The blotter test and the mycotoxins presence were evaluated by thin layer chromatography, using a completely randomized design. The data were submitted to analyses of variance and regression. The genera Fusarium presented linear increasing incidence due to humidity increasing, whereas Aspergillus spp. and Penicillium spp. had their incidences decreased. It was observed that the possible production of aflatoxins, associated to corn grains, still in the field, and, that the anticipation of the crop harvesting, followed by immediate drying assures the sanitary quality of the corn grains.