subtilis PPB9 improved seed germination and tomato seedling vigour. They showed the potential to solubilize phosphate and fix nitrogen. The strains produced hydrogen cyanide, chitinases, siderophores, biofilm, and indole acetic acid.

rolfsii was significantly inhibited by both rhizobacteria and supported their growth as a carbon source. rolfsii in dual culture (PPB3 88% and PPB9 71% inhibition), and culture filtrate assays (PPB3 53–100% and PPB9 54–100% inhibition at various concentrations). Of the six strains screened, Stenotrophomonas maltophilia PPB3 and Bacillus subtilis PPB9 showed the superior performance displaying the highest antagonism against S. The selected promising strains were tested further for plant-growth-promoting and biocontrol potentials under in vitro, greenhouse, and field conditions. rolfsii in dual culture and culture filtrate assays. The present study screened six rhizobacterial strains for antagonism against S. Although rhizobacteria are prolific candidates, comprehensive reports regarding their use in tomato disease management are limited.

The use of rhizobacteria for the biological control of Southern blight disease is a potent alternative to chemical fungicides. Southern blight of tomato caused by Sclerotium rolfsii can cause severe plant mortality and yield losses.

Fungicide for southern blight