Biological and chemical management of web blight disease of urd bean caused by Rhizoctonia solani Kuhn.

Eight fungicides and one bio-control agent were screened in vitro against Rhizoctonia solani causal agent of web blight, of urd bean. Propiconazole, hexaconazole, carbendazim, tebuconazole and epoxiconazole were tested at 1.25, 2.5, 5.0 and 10 (ug/ml concentration whereas mancozeb, probineb and thiophanate methyl at 25, 50, 100 & 200 ug/ml concentration respectively. Epoxiconazole inhibited the growth at 2.5, 5.0, and 10 (ug/ml concentration while propiconazole at 5.0 and 10.0 ug/ml. Carbendazim was effective at 10.0 ug/ml and mancozeb at 200m g/ml where as thiophanate methyl was effective at lOOug/ml and 200ug/ml, tebuconazole and probineb showed non-significant effects. Bio-control agent Trichoderma virens inhibited the mycelial growth of R. solani to the extent of 59.1% in dual culture method and 52.17 % in volatile compound production method. Based on effectiveness of fungicides in vitro, they were further tested under field conditions. Propiconazole @ 0,1 % applied thrice as prophylactic spray showed lower disease severity, higher grain yield as well as maximum 1000 grain weight followed by carbendazim @ 0.1%, mancozeb c 0.25 % respectively.