Organic carbon (C) is often applied to agricultural soils to increase soil organic matter, however, its mechanistic effects on soil P transformations and availability resulting from stimulation of microbial activities and changes in microbial communities remain uncertain. This study investigated the responses of soil P availability, P fractions and phoD harboring bacterial and fungal communities to two dose rates (5 and 10 mg C g⁻¹ dry soil) of labile C (glucose) in bulk and rhizosphere soils planted with maize in a P-deficient soil (Oxisol). Both doses of glucose significantly increased available P concentrations (over a 47-day period) in soils without maize, and in the bulk and rhizosphere soils of maize, resulting in the promotion of maize growth. Glucose additions altered soil phoD harboring bacterial and fungal community composition and stimulated the growth of keystone P-solubilizing microorganisms, such as Bradyrhizobium and Eupenicillium, in soils with maize. Co-occurrence network analysis showed that glucose enhanced interactions between phoD harboring bacterial taxa relative to that of fungal taxa, whether in individual networks or in combined networks. Our results highlight the importance of labile C in facilitating changes in soil P-solubilizing bacterial and fungal communities of a P-deficient soil. These findings provide crucial information to guide P-cycling management strategies via microbial regulation in agro-ecosystems.

有机碳（C）通常用于农业土壤以增加土壤有机质，然而，其对微生物活动和微生物群落变化的刺激导致的土壤磷转化和有效性的机制影响仍然不确定。本研究调查了土壤 P 有效性、P 组分和含有细菌和真菌群落的phoD对两种剂量率（5 和 10 mg C g ^-1干土壤）的不稳定 C（葡萄糖）在种植玉米的散装和根际土壤中的响应。缺磷土壤（Oxisol）。两种剂量的葡萄糖都显着增加了不含玉米的土壤以及玉米块体和根际土壤中的有效磷浓度（超过 47 天），从而促进了玉米的生长。添加葡萄糖改变了土壤phoD含有细菌和真菌群落组成，并刺激了玉米土壤中关键的溶磷微生物的生长，如慢生根瘤菌和正青霉。共生网络分析表明，相对于真菌类群，葡萄糖增强了携带phoD 的细菌类群之间的相互作用，无论是在单个网络中还是在组合网络中。我们的结果强调了不稳定 C 在促进缺磷土壤中土壤溶磷细菌和真菌群落变化方面的重要性。这些发现为通过农业生态系统中的微生物调控指导 P 循环管理策略提供了重要信息。