Evaluation of Selected Systemic and Non Systemic Fungicides In Vitro and In Vivo condition against Web Blight Disease of Urd Bean caused by Rhizoctonia solani Kuhn SANTOSH KUMAR*, HS TRIPATHI AND DEEPAK SINGH Department of Plant Pathology, G.B. Pant university of Agriculture and Technology, Pantnagar 263 145 (U.K.). ABSTRACT Six fungicides were tested at different concentration in in vitro and in vivo for the management web blight of urd bean. Tilt, contaf, and bavistin were screened against R. solani at 1.0, 5.0, 10.0, 15.0 and 20.0ppm concentrations for their antifungal activity where as captaf, sulphur, and mancozeb at 1.0, 25.0, 50.0, 100.0 and 400.0ppm concentrations, respectively. At 15ppm concentration bavistin (0.1%), tilt (0.1%) completely checked the growth of the fungus. Based on effectiveness of fungicides in vitro, they were further tested under in vivo conditions. Bavistin @ 0.1% applied as seed treatment followed by foliar spray showed lowest disease severity, highest grain yield as well as maximum 1000 grain weight followed by tilt @ .1 per cent. Keywords : Web blight, Rhizoctonia solani, urd bean, fungicides *Corresponding Author E-mail : santosh35433@gmail.com INTRODUCTION Urd Bean or Blackgram (Vigna mungo L.) is one of the ancient pulse crop and extensively grown in India. Among the fungal diseases web blight of urd bean caused by Rhizoctonia solani Kuhn is a serious problem and causes yield losses up to 20- 30 % (Shailbala and Tripathi 2007). It is considered one of the important causes for stagnated productivity of the crop in the country (Dubey and Patel, 2001). The first symptoms appear as small circular brown spot on the leaves. These spot enlarge often show concentric banding and surrounded by irregular water soaked areas. The mycelium on infected leaves appear as spider web thus suggested the name web blight disease. The present study was conducted to evaluate different systemic as well as non-systemic fungicides for effective management of this disease MATERIALS AND METHODS Cultures of R. solani was isolated from naturally infected urd bean leaves on PDA medium and then it was further purified by hyphal tip method and maintained on PDA in culture tubes at 28 + 1°C in BOD incubator for further studies. Desired concentrations of fungicides were screened using “poison food technique”. Stock solution of each fungicide was prepared by dissolving weighted quantity of fungicide in a measured volume of sterilized distilled water and added to double concentrated sterilized PDA medium. The stock solution was thereafter added to double strength sterilized PDA. The amount of stock solution to be added to medium was calculated using following formula(Eq.1): C 1 V 1 = C 2 V 2 (Eq.1) Where, C 1 = Concentration of stock solution, C 1 = Concentration of stock solution, V 1 = Desired Concentration (μg/ml), C 2 = Volume (ml) of the stock solution to be added and V 2 = Measured volume (ml) of the medium Medium amended with desired concentration of selected fungicides was poured into sterilized Petri plates (90 mm diam). For each concentration of fungicide, three replication was maintained. After solidification of medium, the plates were centrally inoculated with 5 mm disc of fungus cut from edge ARTICLE INFO Received on : 20.01.2014 Revised received on : 20.02.2014 Accepted on : 27.02.2014 Published online : 27.03.2014 ISSN : 2348-8808 (Print ), 2348-8867 (Online) Journal of AgriSearch 1(1):45-48