In recent years, high levels of mycotoxins such as deoxynivalenol (DON) in Michigan maize (Zea mays L) grain have been an issue for growers. This is caused by the interaction between hybrid susceptibility to ear rot, ideal weather conditions, and western bean cutworm (WBC) damage. In 2017 and 2018, field experiments were conducted at nine locations to determine best management strategies for mycotoxins in Michigan and the Great Lakes region. Treatments included three host plant resistance levels, fungicide application, and three insect trait packages. A subset of four site-years with DON levels greater than 2 μg g-1 were used for in-depth analysis. Host plant resistance and fungicide application did not lower DON levels across any of the site-years. Data from this research provided further evidence that the Cry1F Bt trait is ineffective against WBC in the Great Lakes region. Hybrids with the Vip3a Bt protein lowered WBC incidence although DON control was limited to one out of three site-years. Western bean cutworm incidence showed a significant correlation with ear rot incidence at two of four site-years where the environment was not conducive to fungal infection. In order to evaluate the occurrence of multiple mycotoxins across Michigan environments, samples from one hybrid with no fungicide application were selected from each of the nine locations across two years and analyzed for 26 different mycotoxins. Contamination from multiple mycotoxins was found in every sample with all samples having at least four mycotoxins present. Overall, mycotoxin contamination continues to be a problem in the Great Lakes Region and limited options are available to growers for their management.
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