Effects of Chemigation with Chlorothalonil and Diniconazole on Soil Fungi and Pod, Peg, and Stem Diseases of Peanut. Donald R. Sumner, Professor, Plant Pathology Department, University of Georgia Coastal Plain Experiment Station, Tifton 31793-0748. Robert H. Littrell, Professor Emeritus, Plant Pathology Department, University of Georgia Coastal Plain Experiment Station, Tifton 31793-0748. Plant Dis. 73:642-646. Accepted for publication 17 February 1989. Copyright 1989 The American Phytopathological Society. DOI: 10.1094/PD-73-0642.

Chlorothalonil and diniconazole were applied to peanut in microplots through irrigation water with hand sprinklers or by conventional sprays for control of leaf spots. Soil was infested with Sclerotium rolfsii or Rhizoctonia solani anastomosis group 4 (AG-4) or was noninfested. Foliage disease caused by Cercosporidium personatum, populations of R. solani AG-4 in soil, and the number of lesions on pods, pegs, and stems were usually reduced by treatments with fungicides (compared with no fungicide) but there were usually no differences between application methods. Chlorothalonil reduced the severity of pod rot in soil infested with S. rolfsii.