Fungicide resistant Frogeye Leaf Spot (Cercospora sojina) is found in several soybean production regions in North Carolina. This study identified fungicide resistance in the counties assayed in 2017. The mechanism for fungicide resistance development is still poorly understood; however, the effects of resistance may be mitigated by using integrated pest management strategies. Rotation of fungicide chemistries, use of mixed modes of action, and other cultural disease management practices can reduce losses to disease like Frogeye Leaf Spot.
This trial has demonstrated that strobilurin resistant populations of Cercospora sojinaare present in North Carolina, and producers should select fungicides that utilize multiple modes of action or not utilize single FRAC 11 fungicides to avoid control failures. Additionally, this project will provide information about the mechanism for development of fungicide resistance, which may be used to prevent fungicide resistance in other fungal pests of soybean.