Arbuscular mycorrhizal fungi have a greater role than root hairs of maize for priming the rhizosphere microbial community and enhancing rhizosphere organic P mineralization

Root hairs, arbuscular mycorrhizal (AM) fungi and rhizosphere microbiome all play important roles in mycorrhizal plant phosphorus (P) absorption. However, how the plant-AM fungi-rhizosphere microbiome continuum interacts efficiently to promote the use of soil P is still unclear. Here, we present results of a controlled environment experiment to reveal the effect of root hair, AM fungi and their interaction on rhizosphere microbial Po cycles. Compared to root hairs, AM fungi contributed more to active microbial community assembly, functional gene recruitment and Po mineralization. The rhizosphere microbial Po mineralizing process contributed more than half of plant P assimilation in the P limited condition. The application of inorganic P (Pi) reduced the effect of root hairs and AM fungi on rhizosphere microbial community assembly and Po mineralizing ability. Our findings demonstrate the importance of AM fungi for maize as a driving force for rhizosphere microbial recruitment and function. • AM fungi and root hairs are functionally redundant in maize. • AM fungi had a greater impact on microbial structure than root hairs. • AM fungi had a greater role on microbial P mineralization than root hairs. • Microbial Po mineralization contributed more than half of plant P nutrient. • Application of Pi reduced rhizosphere microbial network and Po mineralization.