Moderate Phosphorus Application Reshapes Rhizosphere Microbial Ecology and Coordinates Host Metabolic Responses to Improve Sweet Potato Yield and Quality: A Multiomics System-Level Analysis

Sweet potato is an important food, feed, and industrial crop whose storage root development and quality depend on phosphorus (P) availability, yet plant–soil–microbe responses to P fertilization remain unclear. We integrated agronomic, metagenomic, transcriptomic, metabolomic, and WGCNA analyses comparing moderate P application (P110; 110 kg P2O5 ha–1) with no P (P0). P110 increased soil organic carbon by 45.03% and available potassium by 9.58%; organic/inorganic P declined, while available P remained unchanged. Rhizosphere shifts included higher Acidobacteriota, Basidiomycota, and fungal diversity. P-cycling genes pckA, gcd, and ppk were higher, indicating altered metagenomic potential for soil P turnover. P110 increased storage roots per plant by 20.31–27.83%, yield by 31.88–41.45%, and plant P accumulation by 134.01%. Multiomics-linked hub genes (ARR6, LRR4, LRR3, FKF1, TIC100) and pathways to root traits, yield, and quality. Moderate P coordinates rhizosphere microbial ecology with host transcriptional and metabolic responses, improving P-use, yield, and quality.