A comparative study of strobilurin and triazole treatments in relation to the incidence of fusarium head blight in winter wheat, grain quality and safety

Field experiments were conducted over 3 years to assess the effects of fungicides (F) containing strobilurins (alone and in mixture with morpholine, triazoles) and triazoles (epoxiconazole or propiconazole) on winter wheat 'Zentos' grain quality, incidence of Fusarium head blight (FHB) in the field, grain contamination with fungi and mycotoxins. The effect of strobilurins and triazoles on the parameters tested was more dependent on the weather conditions of the growing season than on the F applied. The incidence of FHB was low in 2002 and 2003, but high in 2004. Averaged data suggest that strobilurin treatments decreased (lie level of FHB. In 2002, grain contamination with fungi was lower than in 2003 and 2004. The data on the impact of fungicides on post-harvest grain infection with Fusarium spp. and contamination with mycotoxins deoxynivalenol (DON), zearalenone (ZEN) and T-2 were controversial. The fungicides only insignificantly affected protein and gluten concentration in grain, as well as sedimentation and falling number. All grain quality components were especially dependent on the year (significant at P<0.01). However, fungicide application significantly, at P<0.01, increased grain protein and gluten yields: they were higher for the strobilurin-treated plots (with a small exception) than for the untreated and those treated with propiconazole.