Synergistic effects of soil treatment with Serendipita indica and Azotobacter chroococcum on physiological parameters and yield of rice (Oryza sativa L.)

The study aims to investigate out the effects of Azotobacter chroococcum and Serendipita indica inoculation, individually and in combination, on photosynthetic pigments, relative water content (RWC), and morpho-agronomic traits in rice varieties 1718 and 1121. A. chroococcum and S. indica were cultured on 4% (w/v) Jaggery broth under shake flask conditions for bulk multiplication and chlamydospores production. Field studies were conducted to assess their individual and combined effects on plant features such as photosynthetic pigments, leaf water content, plant height, leaf length, panicle count, grain production, and root length. Statistical analysis was performed using analysis of variance (Duncan’s test) at a 5% significance level. The combined treatment yielded the highest improvements, with a notable increase in chlorophyll content, RWC (up to 100%), and plant growth parameters. Rice variety 1718 responded better overall, while variety 1121 showed specific improvements in certain traits. The combined treatment also resulted in the highest grain yield, with a synergistic effect leading to increased biomass production. These findings suggest the potential of co-inoculation with A. chroococcum and S. indica for sustainable rice cultivation.