Control of Fusarium moulds and fumonisin B1 in seeds by gamma-irradiation

The distribution of naturally occurring Fusarium moulds producing fumonisin B, in seeds was determined. Fusarium infection of seed samples ranged from 10%, to 60%, Fusarium moniliforme was the predominant species. Fusarium counts in wheat seeds were 8.1 x 10(4) CFU/g, 6.3 x 10(6) CFU/g in maize and 4.8 x 10(3) CFU/g in barley. Wheat, maize and barley seeds naturally contaminated with varying levels of fumonisin B-1 1.4-5.8, 8.0-13.8 and 0.1-0.5 Erg/g, respectively. F. moniliforme and Fusarium proliferatum were major Fusariunr contaminants producing fumonisin B-1. The effect of gamma irradiation on Fusarium moulds and levels of fumonisin B-1 was also determined. The viable counts of Fusarium in seeds decreased by increasing the radiation dose levels and the growth of Fusarium spp. was inhibited at 4.0 kGy for barley and 6.0 kGy for wheat and maize. Application of radiation dose at 5 kGy inactivated fumonisin Br by 96.6%, 87.1% and 100% for wheat, maize and barley, respectively, and a dose of 7 kGy was sufficient for complete destruction of fumonisin B, in wheat and maize. (c) 2006 Elsevier Ltd. All rights reserved.