Cultural Characteristics of Rhizoctonia solani Causing Sheath Blight of Rice

Abstract

Sheath blight of rice caused by Rhizoctonia solani Kuhn is emerging as a very destructive disease causing heavy yield losses. The present study was conducted at Department of Plant pathology, JNKVV, College of Agriculture, Rewa, (M.P.) with eight culture media viz., Potato Dextrose Agar (PDA), Czapek’s Dox Agar (CDA),Richards medium (RMA), Corn Meal Agar (CMA), Oat meal agar (OMA), Rice leaf extract agar (30%),Rice seed extract agar (10%) and Rice seed extract (10%)+ (2%) sucrose were evaluated against R. solani. It can be concluded that Potato dextrose agar (88.0 mm) and Czapek’s dox agar (87.7 mm) medium supported maximum mycelial growth of R. solani isolated from rice. Whereas, least mycelial growth (75.8 mm) was observed in Rice seed extract agar and Richards agar medium. Mycelial growth was excellent fast, abundant and off white on Potato dextrose agar. Whereas it was fast, abundant and on Czapek’s dox agar. Sclerotia of the fungus initiated within 3 - 4 days in different culture media. Maximum number of sclerotia was produced in Oat meal agar (54.0) closely followed by Potato dextrose agar (51.2) and Czapek’s dox agar (44.6). Maximum weight of 10 sclerotia was recorded in potato dextrose agar (1030.6 mg) followed by Czapek’s dox agar (920.3 mg) and Oat meal agar (884.7 mg). Maximum size of sclerotia were formed in Potato dextrose agar followed by Rice seed extract agar and Corn meal agar.