Fusarium head blight, caused by Fusarium spp. is a major threat to the wheat industry by affecting yield and grain quality. Additionally, production of the mycotoxin deoxynivalenol (DON) in infected grain is a cause of severe losses. A higher proportion of toxin accumulates in the outer layers of kernel which is often removed by milling. To evaluate genotypic differences for toxin accumulation in different tissues of infected grain, we compared 39 locally adapted soft winter lines (21 white and 18 red) representing range of FHB resistance. DON was quantified in a whole grain sample and milled fractions of bran and flour. On average, white lines accumulated significantly higher quantities of DON in all fractions compared to red, while the ratio DON-bran/ DON-flour was lower (p<0.05). The 39 lines were also evaluated for different measures of FHB resistance in the field using two different artificial inoculation methods. Since the amount and duration of moisture available to infected wheat heads influences visible infection and toxin accumulation, a bagging method after spray inoculation (SB) was compared with misting treatment that followed grain spawn inoculum (GS). The methods were compared based on measures of Incidence, Severity, Index, Fusarium damaged kernels (FDK) and DON accumulation in whole grain. The methods were significantly correlated (p<0.05) in ranking genotypes for DON accumulation and FDK, while environmental and genotypic effects were observed in the other measures.
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