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Collars rot disease of brinjal caused by Sclerotium rolfsii is a threatening disease in eastern coastal regions of Odisha. Due to its soil borne nature, this disease is very difficult to be managed by chemical fungicides. Rhizosphere soil of healthy brinjal plants was used for isolation and screening of native bacterial antagonists for probing their biocontrol efficacy and plant growth promotion potential. Among 54 bacterial strains isolated from rhizoplane and rhizosphere of brinjal roots, five isolates viz. isolate-01, isolate-17, isolate-23, isolate-24 and isolate-32 were found highly inhibitory against mycelial growth of S. rolfsii in dual cultures. Highest inhibition of radial mycelial growth of pathogen in dual culture was induced by isolate-32 (77.8%) followed by isolate-24 (74.8%). In greenhouse experiments percent disease incidence (PDI) was lower in artificially inoculated brinjal plants treated with isolate-32 (6.3%) and isolate-24 (8.6%), with percent disease reduction over control of 88.5% and 84.3%, respectively. These isolates also exhibited plant growth promoting characteristics as evident by significant increase in plant height, fresh and dry weight of treated brinjal plants as evident by higher vigour index of 798 and 781.3 of the plants treated respectively with isolate-32 and isolate-24 as compared to vigour index of 297.2 in non-treated plants. The study concluded that the two native rhizobacteria isolated from root zone of healthy brinjal plants could successfully protect the brinjal plants from the lethal infection by Sclerotium sp. while enhancing the overall growth of the treated plants.

Key words: Brinjal, Biocontrol, PGPR, Sclerotium rolfsii.