Resistance of Sorghum to Colletotrichum graminicola. A. S. Ferreira, Graduate Student, Botany and Plant Pathology Department, Purdue University, West Lafayette, IN 47907. H. L. Warren, Research Plant Pathologist, Botany and Plant Pathology Department, Purdue University, West Lafayette, IN 47907. Plant Dis. 66:773-775. Accepted for publication 19 December 1981. This article is in the public domain and not copyrightable. It may be freely reprinted with customary crediting of the source. The American Phytopathological Society, 1982. DOI: 10.1094/PD-66-773.

Twenty-three sorghum (Sorghum bicolor) cultivars were evaluated in the greenhouse and at the Purdue Agronomy Farm for resistance to Colletotrichum graminicola. Seedling blight reactions in the greenhouse were significantly correlated with leaf blight reactions of adult plants in the field (r = 0.87**, P<0.01), although leaf anthracnose severity was usually higher in the field than in the greenhouse. None of the sorghum seedlings inoculated with C. graminicola 15 days after planting produced anthracnose symptoms; however, seedlings inoculated 25 or 35 days after planting in the greenhouse produced typical anthracnose lesions. Susceptibility or resistance to C. graminicola could be determined 25–35 days after planting at the four- to seven-leaf stages. The fungus sporulated in lesions on cultivars susceptible and resistant to C. graminicola but not in lesions on cultivars that were hypersensitive-resistant.

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