Quality Parameters in Small Grains from Minnesota Affected by Fusarium Head Blight

Recent epidemics of Fusarium head blight (FHB) severely damaged the hard red spring wheat and barley crops in Minnesota. Samples of commercial grain were analyzed in 1993 and 1994 to determine the effects of FHB on several quality parameters. Wheat test weight (TW) averaged 832 kg m^-3 (55.4 lb/bu), thousand kernel weight (TKW) averaged 27.4 g, and the proportion of visually scabby kernels (VSK) averaged 11.0%. Deoxynivalenol (DON) was detected in 493 of 500 samples (98.6%). The mean concentration was 8.3 μg/g (range = 0.0 to 44.7 μg/g). Scab in wheat could rapidly be estimated using easy-to-prepare visual comparison standards. Scores of percent VSK were correlated with DON concentration at r = 0.897 and 0.908 in 1993 and 1994, respectively. TW and TKW were less effective estimators of DON (r = -0.622 and -0.550, respectively). DON was detected in 100 of 100 six-row barley samples collected during the survey and averaged 10.4 μg/g (range = 0.5 to 39.7 μg/g). DON concentration in barley could not be effectively estimated with grading parameters including TW, TKW, percent plump kernels, or a visual index of kernel discoloration. In 28 samples of oats, DON averaged 1.4 μg/g (range = 0.0 to 6.4 μg/g). Nivalenol was not detected in any of the 628 samples analyzed during the two-year study.