The growth-promoting effects of sodium alginate-montmorillonite immobilized phosphate-solubilizing bacteria on bermudagrass under salt stress

This field study evaluated the ecological effects of immobilized phosphate solubilizing bacteria (PSB) on the remediation of saline-alkali soil. Using Staphylococcus succinus YJ, we developed a sodium alginate-montmorillonite immobilized agent and applied it to bermudagrass grown on saline soil in Dongying City, Shandong Province. Compared to free bacterial liquid and control treatments, both PSB applications significantly altered the structure of the rhizosphere microbial community without reducing species richness. In particular, the immobilized agent outperformed free bacteria by specifically enhancing soil moisture and total nitrogen content, while enriching functional taxa (eg, Pseudomonas, Shewanellaceae) and metabolic pathways related to nitrogen cycling. Although the prediction of FAPROTAX indicated a potential risk of enriching pathogenic functions, immobilized PSB proved more effective in constructing a stable, growth-promoting microecological niche. We conclude that this immobilization technology is a promising strategy for improving nutrient cycling and microenvironment quality in the restoration of saline-alkali land.