THE EFFECT OF OSPHF1 ON THE COMPOSITION AND STRUCTURE OF RHIZOSPHERE SOIL MICROORGANISMS IN RICE

Plant-microbe interactions represent a pivotal strategy for optimizing crop growth, and phosphorus (P) nutrition-related genes can mediate this process by regulating the composition of the rhizosphere microbial community. To investigate the effects of OsPHF1 ( Phosphate Transporter Traffic Facilitator 1 ) on the rhizosphere microbiota, we analyzed the differences in rhizobacterial community structures between OsPHF1 functional loss mutants ( Osphf1 ) and wild-type (WT) rice plants. High-throughput sequencing of 16S rRNA gene amplicons was performed to characterize the composition of the rhizosphere microbial community. The colonization abundances of Bacillus and Paenibacillus were quantified using the plate counting method, and pot experiments were conducted to verify the growth-promoting effects of Bacillus subtilis . The results show that the rhizobacterial community structure of Osphf1 mutants undergoes significant alterations, with distinct enrichment of taxa such as the phyla Pseudomonadota, Bacillota, Bacteroidota and Verrucomicrobiota. Within the phylum Bacillota, the abundances of the genera Bacillus and Paenibacillus in the rhizosphere of Osphf1 mutants are significantly higher than those in the rhizosphere of WT plants. The colonization amounts of Bacillus subtilis , Paenibacillus mucilaginosus and Paenibacillus polymyxa in the rhizosphere of Osphf1 mutants are all significantly increased. Inoculation with Bacillus subtilis significantly improves the aboveground fresh weight of rice plants, with an increase of 22.7% in WT plants and a more prominent increase of 31.6% in Osphf1 mutants. In conclusion, the OsPHF1 gene is involved in regulating the rhizosphere microbial community structure of rice, and specifically affects the rhizosphere enrichment and colonization of Bacillus species. These findings provide novel insights into the interaction mechanisms among plant nutrient-related genes, the microbiome and plant growth.