Evaluation of various herbicides on the control of sheath blight disease (Rhizootonia solani Kuhn) on rice

Abstract

Both in vitro and in vivo studies on the effect of few common herbicides on Rhizoctonia solani and on sheath blight of rice, were carried out. The in vitro studies revealed that Propanil (Stam P.34) vras the most toxic herbicide to Rhizoctonia solani Kuhn, the rice sheath blight pathogen, which completely inhibited nycelial growth at a very low concentration of 125 ppm. Benthiocarb, Nitrofen (Tok E.25) and Butachlor also have high potentiality in decreasing radial growth and also in inhibiting the formation of sclerotia Soil borne sclerotia was found the major source of inoculam in initiating sheath blight diseases. Among the various herbicides tested, Nitrofen, Propanil and Butachlor reduced the degree of pathogenicity of soil borne sclerotia of R. solani* Propanil effected maximum reduction of sheath blight in pot culture experiments followed by Nitrofen. Butachlor and Nitrofen were equally effective in reducing sheath blight under pot culture, experiment. Nitrofen (Tok E.25) applied at 1.5 kg ai, 1.75 leg ai were equally effective as Hinosan in reducing sheath blight in field trial also.