Peanut Foliar Fungicides: Relationships Between Leafspot Control and Kernel Quality

Abstract

Abstract The effectiveness of foliar fungicides for control of peanut leafspot caused by Cercospora arachidicola Hori and Cercosporidium personatum (Berk. & Curt.) Deight, was evaluated from 1971–1974. Benomyl, chlorothalonil, triphenyl-tin-hydroxide and copper hydroxide were applied at recommended rates by conventional ground sprayer at 14-day intervals. Leaf-spot severity was rated by determining percent defoliation and infection. All fungicide-treated plots had less defoliation and infection than the untreated control plots. Kernel quality was determined using Federal-State Inspection Service procedures. Plots sprayed with chlorothalonil had better quality kernels than those from any other fungicide treatment. However, kernels harvested from the untreated control plots had significantly better quality than those from the chlorothalonil-treatment. Kernels harvested from the benomyl and copper hydroxide treatments were slightly inferior in quality than the chlorothalonil treatment. Kernels from the triphenyl-tin-hydroxide treated plots were significantly inferior in quality than those from plots treated with other fungicides. These data indicate that while kernel quality is not related to leafspot control, certain foliar fungicides adversely affect peanut kernel quality probably by altering the ecology of the geocarposphere.