Isolation and assessment of genetic diversity of plant growth promoting and abiotic stress tolerant chickpea mesorhizobia

A study was conducted to isolate plant-growth-promoting and abiotic stress tolerant chickpea Mesorhizobia from arid and semi-arid zone soils of Rajasthan. Fifty-one cultures were isolated from chickpea root nodules and identifed based on cultural, morphological, and biochemical characteristics. These strains were screened for plant growth-promoting activities and 17 strains were able to produce IAA, nine strains could solubilize phosphate, and 30 strains exhibited siderophore production activity whereas, 20 strains showed a positive result for ammonia production. Abiotic stress tolerance was tested in isolated cultures using different pH, temperature, and salt concentrations. ARDRA based fngerprinting profiles in chickpea mesorhizobial isolates revealed genetic variation among the cultures. Rhizobial inoculation has promising effects on the establishment and symbiotic performance of legumes so, developing microbial formulations of compatible rhizobia with multiple PGP activities and stress-tolerant traits will prove very benefcial for arid and semi-arid areas where native rhizobial strains are not predominant.