Contents of trichothecenes in oats during official variety, organic cultivation and nitrogen fertilization trials in Finland

Summary

Natural toxins, such as mycotoxins, have emerged as a significant factor affecting the safety image of cereal grains as a raw material for the food and feed industry. The aim of the present study was to investigate the contents of trichothecenes in representative samples of oats during official variety, nitrogen fertilization and organic farming trials in Finland, 1997–1999. Further objectives were to promote industry and commerce by selection of high-quality oat varieties for various applications. The official variety trials conducted at 8–10 locations were managed following standard protocol. There were 2 types of agronomy trial, the first included comparison of oat cultivars grown in conventional and organic farming systems at 6 locations, and the second used 5 nitrogen rates (0, 40, 80, 120 and 160 kg N ha-1) at 2 locations. Regardless of wet cold summer occurring in Finland during 1998, the concentrations of Fusarium toxins were lowest during this 3 year monitoring period. More mycotoxins were produced during the warm, dry summers of 1997 and 1999 than in 1998. In all, 55% of the oat samples in the official variety trials contained deoxynivalenol (DON) within the range of 50– 896 µ g kg-1. The differences in DON concentrations between organic and conventional cultivation were small. The results showed also that the use of various nitrogen fertilization levels only slightly affected the trichothecene concentrations. The contents of trichothecenes in Finnish grains appeared to be similar to or lower than those reported earlier in the Northern Hemisphere.