Abstract

Seven plant growth-promoting rhizobacterial (PGPR) strains were isolated from the rhizoplane and rhizosphere of wheat from four different sites of Pakistan. These strains were analyzed for production of indole acetic acid (IAA), phosphorous solublization capability and inhibition of Rhizoctonia solani on rye agar medium. Strains WPR-51, WPR-42 and WM-30 were selected to test in planta antagonistic activity on two wheat verities infected with R. solani. These three strains belonging to Azotobacter and Azospirillum produced IAA ranging from 19.4 to 30.2 ug/ml and possessed phosphorus solublization capability. Out of these three strains WPR-51 and mixture of all three strains showed maximum inhibition of R. solani growth. These strains positively affected the germination of wheat as well as increased biomass and root shoot length by inhibiting R. solani growth when tested in pot experiments. PGPRs can be used as biocontrol agents that inhibit root rot and also strengthen the plant for better growth.

Key word: Biological control, plant growth-promoting rhizobacterial, Rhizoctoniasolani, antifungal activity, wheat.