Differences Between Barley, Oats and Wheat in the Occurrence of Deoxynivalenol and Other Trichothecenes in Norwegian Grain

The amount of the Fusarium toxins deoxynivalenol (DON). 3-acetyIDON, nivalenol and fusarenon-X have been determined in about 3000 samples of barley, oats and wheat grown in Norway, The samples were collected in the period 1988-1994. and grouped according to grain species, year of production, district and sample category. The DON content was found to be significantly higher in oats than both barley and wheat in grain produced by ordinary grain producers in Norway, Of samples collected from grain silos. 68,7% of the barley, 97.1% of the oats and 66,3% of the wheat samples were found to contain 30 ;ig,kg of DON or more. The proportion containing 1000 ^g kg or more was 2.1.13.4andO.O% inbarley, oats and wheat, respectively. However, these variations in contamination level were not reflected in the results from two field trials, where the grain species were grown side-by-side in the same fields. The dilferences in contamination level between the grain species seem to be due partly to edaphic and agrotechnical factors and partfy to variation in the susceptibility to different Fu.sarium species in interaction with climatic factors. Nivaienol (^ 50 fig kg) was detected in 8.3% of the barley samples, 8.2% of the oats and 0.4% of the wheat samples. Samples collected at the grain silos were then not included