Bacterial wilt caused by Ralstonia solanacearum, a genetically diverse soil-borne pathogen with a wide host range, is a devastating plant vascular disease (Hayward, 1991). No effective chemical product is available for Ralstonia-induced wilt. Alternative methods such as biological control agents (BCAs) have shown effectiveness. Bacillus subtilis is a non-pathogenic bacterium that lives in soil, often in association with roots of higher plants and it also produces a variety of biologically active compounds with a broad spectrum of activities towards phytopathogens and that are able to induce host systemic resistance. Thirty Bacillus subtilis isolates were isolated from rhizospheric soil of healthy brinjal plants from Hyderabad Karnataka region. These isolates were evaluated by screening their antagonistic ability to reduce incidence of bacterial wilt of brinjal caused by Ralstonia solanacearum in vitro. All the isolates showed the varied level of inhibition of Ralstonia solanacearum. Among different isolates, BS6 showed highest inhibition zone of 19.5mm diameter followed by BS-10 showed 18.16 mm and least zone of inhibition was produced by an isolate BS-11 of 5.5 mm diameter.

Download this article as