Effect of soil solar!zation and biofumigation on stem rot disease of potato caused by sclerotium rolfsii

Abstract

Abstract : The role of soil solarization and biofumigation on stem rot disease of potato caused by Sclerotium rolfsii was investigated through the present study conducted during July 2015 to June 2016. Soil solarization was done by covering soil with transparent polyethylene sheet for four weeks. Appropriate antifungal biofumigant was selected by in vitro screening of cabbage, cauliflower, mustard and broccoli leaf extracts against a virulent isolate of S. rolfsii. Mustard leaf extract was found to be the most effective in inhibiting the radial growth (78.79%) and sclerotia formation (83.13%) of S. rolfsii. Selected biofumigant plant was grown, chopped and incorporated into the soil. The stem rot susceptible potato variety Cardinal was used as host plant. Soil solarization and biofumigant were applied alone or in combination to manage the stem rot disease of potato in the field. Among the different treatments, combined application of soil solarization and biofumigation (T5) was appeared to be superior in reducing the pre- and post-emergence mortality of potato seedlings. The lowest disease incidence (26.67%) and plant disease index (PDI) (29.86%) were found in the treatment T5 followed by that of T3 (Biofumigant). Maximum increase (121.67%) of potato yield was also found in plots treated with combined use of soil solarization and biofumigation followed by that of biofumigant (83.02%) over control. The results suggested that combined use of soil solarization and biofumigation is the most effective for the management of S. rolfsii compared to the individual treatment either with soil solarization or biofumigation.