The Effect of Weather and Agronomic Practice on Deoxynivalenol Mycotoxin in Durum Wheat

Deoxynivalenol (DON) produced by Fusarium graminearum and F. culmorum in durum wheat (Triticum turgidum L. var. durum) is an important food safety issue for the cereal chain. A number of agronomic practices are known to affect the infection and mycotoxin production by these Fusarium species in cereal grains. A field study was conducted to compare the natural occurrence of DON in durum wheat grown under conventional (n = 67 samples) and organic (n = 50) farming conditions during two consecutive crop years. DON mean levels were 95 and 194 µg/kg in conventional and organic durum wheat, respectively. The incidence and levels of DON were higher in the second crop year due to higher rainfall (> 100 mm) during flowering. Overall, organically managed farming system may provide some reduction in DON levels in durum wheat, which could be attributable to the lower intensity of cultivation in addition to the different system of cropping rotation. However, favourable weather conditions are likely to be more important for DON contamination than crop system.