Vegetos

Abstract

Bacterial wilt of tomato triggered by soil-born pathogen Ralstonia solanacearum (Smith) cause plant death and significant yield loss. Plant growth promoting rhizobacteria (PGPRs) are the potential biological agents for disease control in crops as PGPRs elicit induced systematic resistance to bacterial and fungal diseases. Among these PGPRs, the strains of Pseudomonas and Bacillus on broad spectrum are highly effective. To investigate potential outcomes to control bacterial wilt, 120 rhizobacteria were screened against R. solanacearum. In-vitro screening confirmed the three strains (PR3, PR9, and PR25) showed the maximum inhibitory potential for the disease. Rhizosphere soil and tomato seedlings were treated with the antagonists and their effects were studied under in-situ conditions. The study revealed that PR25 (Enterobactor) and PR9 (Enterobactor) strains significantly diminished disease incidence and augmented vegetative growth of tomato plants. Plant dry weight showed an upsurge through the inoculation of PR25 and PR9 strains respectively. Strain PR25 was found to be the most regulatory strain in disease suppression and also growth promotion resulting in 76% fresh weight increase compared to control. The study revealed that PR25 and PR9 strains are promising strains.