Effect of Carbon, Nitrogen and Vitamins on Epidemiological Components of Sheath Blight of Rice caused by Rhizoctonia solani Kühn

The rice crop is affected by various biotic and abiotic stresses. The fungal diseases come under major biotic stress, among fungal diseases sheath blight of rice is one of the major threat for cultivation of rice crops. The sheath blight pathogen (Rhizoctonia solani Kühn) is being affected by different sources of nutrients. In this regards, six carbon, eight nitrogen and eight vitamin source were screened against R. solani causing sheath blight of rice. Among the carbon sources maximum number of sheath blight lesions, largest size of sheath blight lesion were recorded when rice plants were inoculated with the inoculums grown on the medium supplemented with sucrose, fructose & lactose together as carbon source. Among the nitrogen sources, significantly, highest level of disease severity (52.09%) was recorded when the R. solani inoculums were provided with urea as a source of nitrogen, followed by calcium nitrate (42.48). In case of Vitamins, highest level of disease severity (43.21%) was recorded due to Thiamine, followed by the combination of three vitamins (Biotin+ Calcium pentothenate + Thiamine hydrochloride (30.62%). The results of present finding indicate that sources of carbon, nitrogen and vitamins are affecting the disease severity. Therefore, precautions should be taken when these are applying in the fields.