Virulence of Anastomosis Groups of Rhizoctonia solani and Rhizoctonia-like Fungi on Selected Germ Plasm of Snap Bean, Lima Bean, and Cowpea. Donald R. Sumner, Department of Plant Pathology, University of Georgia, Coastal Plain Experiment Station, Tifton 31793. Plant Dis. 69:25-27. Accepted for publication 28 August 1984. Copyright 1985 The American Phytopathological Society. DOI: 10.1094/PD-69-25.

Rhizoctonia solani AG-4 and AG-2 type 2, indigenous to the Georgia coastal plain, were highly virulent on cultivars of snap bean, lima bean, pole bean, and cowpea. Snap bean breeding lines B4175, B4173-2X, 208-8R, 5181 R, and Venezuela 54 were more resistant to high inoculum densities (187 and 492 colony-forming units [cfu] per 100 g of soil) of AG-4 than Eagle snap bean, but at 16 cfu/100 g of soil, there were no significant differences. None of the snap bean breeding lines were resistant to R. solani AG-2 type 2. R. solani AG-2 type 1 was highly virulent on cowpea cultivars and slightly to moderately virulent on beans. Rhizoctonia-like CAG-5 was moderately virulent on PI 165426 and Jackson Wonder lima bean. CAG-3 was highly virulent on cowpea cultivars, and CAG-4 was avirulent.