In vitro evaluation of plant extracts and biocontrol agents against Sclerotium rolfsii Sacc. Causing wilt of betelvine

Betelvine (Piper betle Linn.) is most prone to infestation by several soil borne pathogens, among them wilt disease caused by Sclerotium rolfsii Sacc. is one of the most destructive one. The present study was carried out to evaluate aqueous extract of eight different plant species and four antagonistic biocontrol agents under in vitro condition for their inhibitory effect on mycelial growth of S. rolfsii. Among the plant extracts tested at three different concentrations, 15 per cent concentration of all plant extracts were significantly found superior to 5 and 10 per cent. At 15 per cent concentration of plant extracts, maximum 62.19 per cent inhibition of mycelial growth was recorded in tulsi leaf extract followed by marigold leaf extract (57.11%). Among the biocontrol agents tested Trichoderma harzianum I showed maximum antagonistic effect and found to be significantly superior in inhibiting the mycelial growth of S. rolfsii (62.64%).