VIEW ARTICLE

Disease Control and Pest Management

Cultural Practices and the Incidence of Sorghum Downy Mildew in Grain Sorghum. D. M. Tuleen, Research associate, Department of Plant Sciences, Texas A&M University, College Station, TX 77843; R. A. Frederiksen(2), and P. Vudhivanich(3). (2)(3)Professor, and graduate student, respectively, Department of Plant Sciences, Texas A&M University, College Station, TX 77843. Phytopathology 70:905-908. Accepted for publication 11 March 1980. Copyright The American Phytopathological Society. DOI: 10.1094/Phyto-70-905.

Several cultural practices that reduce the incidence of sorghum downy mildew (SDM) in grain sorghum were evaluated in field and greenhouse studies. Growth of oats, barley, flax, sudangrass, or cowpea for 15 days and maize for 17 days in soils infested with Peronosclerospora sorghi significantly reduced SDM inoculum potential. The results suggest merit for short-term crop rotations. Deep-plowing of infested plant residue with a moldboard plow reduced the incidence of infection within the field and significantly increased the grain yield of a commercial hybrid incurring >20% infection with conventional plowing. Delaying planting until April reduced the incidence of disease in two hybrids in a 1979 field test.