Frogeye leafspot (FELS), caused by Cercospora sojina, and Septoria brown spot (SBS), caused by Septoria glycines, are foliar diseases that impact soybean ( Glycine max L. Merr.) production annually. These diseases may cause leaf necrosis, premature leaf drop, or plant death when symptoms are advanced, though significant yield loss is rarely observed in Pennsylvania. This trial tests the effectiveness of foliar fungicide treatments applied at the R3 growth stage on overall plant health yield. This trial was conducted at the Russell E. Larson Agricultural Research Center in Pennsylvania Furnace, PA. Results from the trial help inform soybean growers on the best management to prevent foliar disease in soybeans.
McFeaters et al. (2025) studied this question.