The niche complementarity driven by rhizosphere interactions enhances phosphorus‐use efficiency in maize/alfalfa mixture

Rhizosphere interactions between intercropping maize and alfalfa to increase phosphorus (P) acquisition remain largely unknown. This study aimed to investigate the mechanisms underlying niche complementarity to increase P acquisition in the maize/alfalfa mixture by influencing root/rhizosphere interactions. Maize was grown alone (single maize) or with maize (maize/maize) or alfalfa (maize/alfalfa) with low P (30 mg P kg−1 soil) and high P (150 mg P kg−1 soil) supplies. The target maize had greater shoot biomass and P content when grown with alfalfa than maize. Compared with maize, alfalfa had higher secretion of carboxylates and acid phosphatase, suggesting a stronger capacity to mobilize soil P. Phosphorus deficiency also increased the specific root length and the proportion of thin roots (diameter