Plasma membrane H + ‐ ATPase OsA1 enhances soil organic phosphorus mineralization via Bacillus cereus recruitment in rice

Summary Organic phosphorus (P), which accounts for c. 50% of total soil P, is not directly available for plant uptake and must be first mineralized. Plasma membrane (PM) H + ‐ATPase facilitates the mobilization of insoluble inorganic P by energizing the release of organic anions from roots. However, its role in modulating the rhizosphere microbiome to facilitate soil organic P mineralization remains unclear. To address the gap, we investigated the role of PM H + ‐ATPase in recruiting microbiota for soil organic P mineralization through high‐throughput sequencing and metabolite analysis. Under low P (LP) conditions in nonsterilized soil, wild‐type (WT) rice seedlings exhibited 59%, 73%, and 66% greater shoot P concentration than three PM H + ‐ATPase gene OsA1 mutants, that is, osa1‐1 , osa1‐2 , and osa1‐3 , respectively. Such growth advantage reduced to 33%, 47%, and 39% in sterilized soil, suggesting a microbial contribution. Under LP conditions, organic P mineralization efficiency in the WT rhizosphere was four times greater than under normal P (NP) conditions, whereas no significant difference was observed in the osa1‐1 mutant. The abundance of Bacillus was significantly higher in the WT rhizosphere than in osa1‐1 under LP. Compared with the osa1‐1 rice, WT exhibits significantly higher malate concentration, which could stimulate the growth of Bacillus cereus . Inoculation with B. cereus significantly increased P uptake in both WT and OsA1 mutants compared with the uninoculated control under LP. Together, these findings suggest that OsA1 promoted soil organic P mineralization by recruiting Bacillus through malate exudation. This highlights a cooperative interaction between PM H + ‐ATPase and the rhizosphere microbiome, with important implications for enhancing soil organic P mineralization and P‐use efficiency in rice production.