Mitigation of N₂O emission from granular organic fertilizer with alkali- and salt-resistant plant growth-promoting rhizobacteria.

This article focuses on screening alkali- and salt-resistant plant growth-promoting rhizobacteria (PGPR) strains to mitigate nitrous oxide (N2O) emissions from granular organic fertilizers applied to agricultural soils. Among 29 candidate strains from genera including Bacillus, Achromobacter, Paenibacillus, and Pseudomonas, eleven significantly reduced N2O emissions in microcosm studies, with seven strains demonstrating tolerance to alkaline pH (up to pH 10) and salinity (up to 4%). When inoculated into two types of agricultural soils (Anthrosol and Cambisol), most of these tolerant strains decreased cumulative N2O emissions by 22%–81%, with four Bacillus strains (B. albus, B. licheniformis, B. amyloliquefaciens, and B. subtilis) showing the highest efficiency. The study suggests these PGPR strains have potential for developing bio-organic fertilizers that reduce greenhouse gas emissions, though further research is needed to confirm their effectiveness under field conditions, varying salinity, pH levels, and in the presence of plants.