Impact of fungicides on Rhizoctonia solani Kuhn causing sheath blight disease of rice

Abstract

Rhizoctonia solani Kuhn, is an important pathogen of rice causing sheath blight disease. The pathogen thrives in soil and is polyphagous in nature. Till date no resistant variety has been registered against the disease which is the main reason of dependence on chemical management of the disease. In the present study six chemicals with different concentrations viz. 50 ppm, 100 ppm and 200 ppm along with control were evaluated in vitro against the pathogen. The chemicals were also tested in vivo for management of sheath blight. The in vitro study was conducted using the ‘poisoned food technique’ and the in vivo study was done in the field condition during kharif season in two subsequent years (2018 and 2019). Spraying of the fungicides was advocated twice after the natural infection i.e. at 45 and 60 days after transplanting. The observations revealed that all the fungicides were capable for significant inhibition of the fungus in ‘in vitro’ and the disease in ‘in vivo’ conditions.