Author(s):

Ritu Kumari and RK Ranjan

Abstract: Bacterial wilt or brown rot of potato caused by Ralstonia solanacearum, considered as a destructive disease of potato crops. In the present research work, the bacterial wilt infected potato plant samples were collected from different location of Samastipur district of Bihar (India). Twenty strains of R. solanacearum were isolated and identified based on different biochemical characteristics. The strains of R. solanacearum showed fluidal, irregular and creamy white with pink at the center on TZC medium after 48 h of incubation were selected. The strains of R. solanacearum showed a positive result for the pathogenicity test and produced brown rot symptoms in potato tubers. The results of biochemical studies showed that all the 20 isolates were gram-negative, rod-shaped and positive for potassium hydroxide test, oxidase test, catalase test, nitrate reduction test, production of hydrogen sulfide and citrate utilization test but they showed negative reaction for indole test. Based on the isolation study (colony characteristics on TZC media), ooze test, pathogenicity test, and different biochemical tests, the identity of potato wilt pathogen was established as R. solanacearum. Race characterization showed that strains of R. solanacearum, causing bacterial wilt disease in potato, belong to race 3. The result of biovar showed that the strain of R. solanacearum collected from different locations of Samastipur districts of Bihar belong to bv2 (80%) & bv2T (20%).

Pages: 1762-1767  |  1190 Views  711 Downloads

Download (806KB)