Evaluation of plant extracts on mycelial growth and viability of the sclerotia of Rhizoctonia solani Kuhn In vitro and in soil

In the present study, efforts were made to explore the efficacy of plant extracts against R. solani. Efficacy of six extracts viz., neem, garlic, pongamia, datura, lantana and calotropis were tested. The neem (A. indica) leaf extract and clove extract of A. sativum recorded maximum mycelia growth inhibition by 85.18 and 72.59 percent respectively at 20 percent concentration. The viability of sclerotia was also tested and among them only two viz., neem and garlic were found to be effective in inhibiting sclerotial germination even at lower incubation period of 30 min. both in soil application and in vitro. Lantana and datura inhibited sclerotial germination at higher incubation periods i. e., 18 h and 24 h. rest of the plant extracts tested were ineffective in inhibiting sclerotial germination.