On the several sclerotial fungi isolated from the sheath blight like lesions of rice plants in Japan

Abstract

Recently several sclerotial fungi other than causal pathogen of sheath blight, Pellicularia sasakii, were frequently isolated from sheath blight like lesions of rice plants. Average isolation rates of sheath blight fungus and other sclerotial fungi from the lesions collected from different areas in Japan were 82.6 (256 isolates) and 13.2 (41 isolates) percent respectively. Species of sclerotial fungi other than P. sasakii were as follows: Rhizoctonia oryzae, Sclerotium fumigatum, Sclerotium oryzae-sativae, Rhizoctonia solani (culture type III-B) and Sclerotium hydrophilum. In the Tohoku area sclerotial fungi other than P. sasakii accounted for 40 percent (26 isolates) of 65 isolates tested. Brown sheath blight fungus, R. solani (culture type III-B), was identified by means of hyphal anastomosis.