Fusarium SPECIES AND TRICHOTHECENE MYCOTOXINS IN SUSPECT SAMPLES OF 1985 MANITOBA WHEAT

Abstract

In 1985, abnormally high summer rainfall in southern Manitoba resulted in a high incidence of fusarium head blight symptoms in some samples of wheat delivered to primary elevators. Fifty-three wheat samples, containing between 0.2 and 5.4% (wt/wt) pink kernels and white "tombstone" kernels, were examined for Fusarium species and trichothecene mycotoxins. Fusarium species were found in 48 of the samples with F. graminearum in 30, F. sporotrichioides in 38, F. poae in 21, F. acuminatum in 21, F. avenaceum in 21, F. equiseti in 25, F. culmorum in 3, and F. oxysporum, F. sambucinum and F. subglutinans in 1 each. The mycotoxin deoxynivalenol was found in 39 samples at concentrations ≤ 1.40 ppm and in 1 sample at 3.65 ppm, diacetoxyscirpenol in 20 samples at ≤ 0.08 ppm, HT-2 toxin in 10 samples at < 0.05 ppm, and T-2 toxin in 11 samples at ≤ 0.20 ppm.Key words: Fusarium, trichothecenes, mycotoxins, wheat