Omics-driven research progress on phosphate activation mechanisms and stress adaptability regulation of Phosphate-Solubilizing Microorganisms (PSMs).

Phosphorus (P) is an indispensable macronutrient for crop growth and development, but most phosphorus in soil exists in insoluble forms with extremely low availability. Although the application of traditional chemical phosphorus fertilizers can meet the phosphorus demand of crop growth, the extensive exploitation of phosphate rock resources has led to problems such as phosphate rock depletion and environmental pollution, highlighting an urgent need for sustainable phosphorus management strategies. Phosphate-Solubilizing Microorganisms (PSMs) provide an environmentally friendly biological approach to address this challenge. Existing reviews mainly focus on the basic phosphate-solubilizing mechanisms and agricultural applications of PSMs, but lack integration of cutting-edge directions such as omics-based mechanism analysis, stress adaptability regulation, and compound microbial inoculant design. From the innovative perspective of "omics-driven mechanism analysis - stress adaptability regulation - multifunctional inoculant development," this review systematically summarizes: (1) the distribution characteristics of PSMs and environmental adaptability differences among functional groups; (2) the molecular regulatory networks of core phosphate activation mechanisms (acidification, organic acid secretion, phosphatase production) based on multi-omics, with a focus on comparing mechanism-specificity between bacteria and fungi; (3) the regulatory rules and adaptive mechanisms of PSMs activity under stress factors such as pH, heavy metals, and salinity; (4) the host-specific interaction mechanisms between PSMs and plants, as well as the regulatory effects on rhizosphere microenvironment; (5) the formulation development, field application bottlenecks, and large-scale promotion strategies of PSMs biofertilizers. Finally, the current research limitations (e.g., fragmented molecular mechanisms, significant differences between field and laboratory effects) are critically analyzed, and future research directions are proposed, including integrated multi-omics analysis, breeding of high-efficiency stress-tolerant strains, and long-term field validation. By integrating cutting-edge molecular mechanisms and practical application bottlenecks, this review provides a novel theoretical framework for the precise development and sustainable agricultural application of PSMs, which is of great significance for promoting the construction of an eco-friendly agricultural system.