Integrated Management of Fusarium Head Blight of Wheat Including Organically Allowed Fungicides in the Midwest United States

Globally, Fusarium head blight (FHB) is an economically important disease of wheat. Although several studies have compared disease levels of wheat produced using organic versus conventional management, few studies on FHB have considered specific organic management practices and how integrated management techniques best apply in these systems. Trials in Wisconsin and Indiana were designed to evaluate the management techniques currently available to organic farmers for their efficacy in reducing FHB and deoxynivalenol (DON) content while balancing yield and test weight. The practices evaluated included the use of a moderately resistant cultivar and the application of Organic Materials Review Institute–listed foliar fungicides. In both trial locations, Harpoon, the moderately resistant cultivar, significantly reduced the FHB index, FHB severity, and DON level compared with Kaskaskia, the susceptible cultivar ( P < 0.05). In Wisconsin, Harpoon also significantly reduced the FHB incidence and foliar disease severity while providing increased yield protection ( P < 0.01). Fungicide treatment did not significantly affect the FHB index, DON level, or yield in either location ( P > 0.05). In Indiana, Reynoutria sachalinensis 12.0% (formulated as Pacesetter WS) significantly reduced the FHB incidence in the susceptible wheat cultivar ( P < 0.05). Additional research is needed to evaluate treatments under higher disease pressure.