Impact of the insecticide application to maize cultivated in different environmental conditions on emerging mycotoxins

Maize can be competitively colonized by several fungi that are capable of producing a variety of mycotoxins, mainly fumonisins B (FBs), with a negative impact on maize safety and quality. The aim of this study was to investigate the impact of the insecticide application against European Corn Borer on the contamination of “emerging” mycotoxins and other fungal metabolites co-occurring with the legislated ones in maize for human consumption in North-West Italy from 2009 to 2015. The insecticide application on average significantly increased the yield by 5%, and significantly reduced the ECB incidence and severity and the fungal ear rot incidence and severity compared to the untreated control. Overall, 25 Fusarium mycotoxins and metabolites were detected. The results underline that the use of the insecticide, the most common FBs control practice in temperate areas on food maize, also resulted in significant reductions of other mycotoxins produced by Fusarium spp. of the Liseola section. However, this practice was not generally able to reduce the contents of Fusarium spp. section Discolor and Roseum mycotoxins. In environmental and agronomic conditions that favor deoxynivalenol and other metabolites produced by the previous mentioned Fusarium spp., the insecticide treatment could even increase their contamination.