Fungicide inhibition of aflatoxins, diacetoxyscirpenol and zearalenone production.

The effect of fungicides on the production of aflatoxin by Aspergillus flavus IMI 89717, diacetoxyscirpenol and zearalenone by Fusarium graminearum was studied. In a yeast extract-sucrose medium, dicloran, iprodione and vinclozolin fungicides significantly inhibited mycelial growth of A. flavus at 250 ppm and significantly decreased aflatoxin production at 100, 250 and 500 ppm, respectively. In potato-dextrose broth, these fungicides diminished the mycelial growth of F. graminearum and production of diacetoxyscirpenol and zearalenone at 100 ppm. Sensitivity of toxigenic mycelia to fungicides increased approximately five-fold in a yeast extract-starch medium with an appreciable reduction in sugar uptake and alpha-amylase activity.