Enhancing soil quality and yield through microbial assisted in-situ residue management in rice-rice cropping system in Odisha, Eastern India.

Crop residue management has become more challenging with intensive agricultural operations. Zero tillage and crop residue returns, along with the enhancement of in-situ residue decomposition through microbial intervention, are essential measures for preserving and enhancing soil quality. To address this problem in view of stubble burning, field experiments were conducted in rice-rice (variety Swarna) cropping systems under lowland conditions, wherein the following different residue management practices were adopted viz., conventional cultivation (CC), residue incorporation (RI @ 6 t paddy straw ha-1), residue retention (RR @6 t paddy straw ha-1), and zero tillage (ZT). In this experiment, two microbial products i.e. solid microbial consortium (SMC) at 2.0 kg ha-1) and capsule (10 numbers ha-1), were evaluated in both Rabi (dry) and Kharif (wet) seasons under different residue management practices. The results on soil microbial properties showed that application of either SMC or capsule based formulation could significantly improve the soil organic carbon (SOC) content in ZT (9.51 g/kg), followed by RI (9.36 g/kg), and RR (9.34 g/kg) as compared to CC (7.61 g/kg). There were significant differences in the soil functional properties (AcP, AkP, FDA, and DHA) with microbial interventions across all residue management practices. SOC was significantly positive correlated with cellulase (R2 = 0.64, p < 0.001), ß-glucosidase (R2 = 0.61, p < 0.001), and laccase (R2 = 0.66, p < 0.001) activity; however, the regression coefficients varied significantly with microbial intervention. Moreover, the availability of N, P, and K in soil was significantly (p < 0.05) improved under microbial treatments with either RR or RI practices. Among the different methods of residues management practices, RI with microbial intervention registered a consistent yield improvement (8.4-17.8%) compared to conventional practices with microbial intervention. The present findings prove that the application of decomposing microbial consortia for in-situ rice residue management under field conditions significantly enhances soil quality and crop yield compared to conventional practices.

Rhizobacteria mediated seed bio-priming triggers the resistance and plant growth for sustainable crop production.

Advanced technologies are commonly used in modern agriculture to break the yield barriers and increase crop productivity. Seeds treated with plant growth-promoting rhizobacteria (PGPR) are an effective bio-priming method to introduce beneficial microbial inocula into the rhizosphere or soil. Bio-priming is a type of seed treatment that employs biological entities, which involves the hydration of seeds and inoculation with beneficial microorganisms. Mainly, the seed bio-priming technique improves the seed quality, germination, viability, vigor index, growth promotion, production, and subsequent disease resistance by enhancing the uniform speed of germination and production of others growth regulators. In the majority of cases, bacterial inoculants mostly PGPR are used for seed bio-priming, it is an ecologically comprehensive strategy that uses selected PGPR to promote plant growth by producing regulatory substances, enhancing uptake of nutrients, protecting seedlings/plants from seed or soil-borne pathogens. Bio-priming methods using PGPR inoculants are becoming more common in modern agriculture as an alternative to chemical treatments. They are more environmentally sustainable and safer for future agriculture apart from improving plants and soil health.