Production of mycotoxins by Fusarium graminearum isolated from small cereals (wheat, triticale and barley) affected with scab disease in Southern Brazil

Abstract

Fusarium fungi are known to be pathogenic for plants and mycotoxin producers. The in vitro production of deoxynivalenol and zearalenone was qualitatively evaluated in 24 different isolates of Fusarium graminearum collected from small cereals associated with the scab disease, in southern Brazil. Isolates were cultivated in rice during 14 days at 28ºC. Cultivates were extracted with methanol:water (40:60 v/v) and analyzed by thin layer chromatography. Other trichothecenes (diacetoxyscirpenol, fusarenon-X, neosolaniol and nivalenol) and zearalenol, often produced by Fusarium, were also analyzed. In the conditions used, it was possible to detect zearalenone and deoxynivalenol in 67% and 33% of the isolates, respectively. The presence of zearalenol, diacetoxyscirpenol and fusarenone was also detected. None of the isolates was found to produce nivalenol or neosolaniol.