soil sequencing

To clarify how arbuscular mycorrhizal fungi (AMF) shape the root metabolome and microbiome, particularly regarding Cd and phosphorus (P) allocation, in a hyperaccumulator-crop intercropping system. We measured the rhizosphere microbial diversity and metabolite profiles of co-planted Sedum alfredii (a Cd-hyperaccumulator) and maize mediated by AMF in Cd-contaminated soil. AMF increased maize biomass by 50.29% and P uptake by 43.82%, while promoting S. alfredii biomass by 52.89% and P accumulation by 36.63%. The elevated available P concentration in the rhizosphere enhanced P acquisition. Notably, AMF reduced Cd concentration in maize by 43.14% but increased it in S. alfredii by 51.89%. AMF induced pH changes, leading to a decrease in the S. alfredii rhizosphere and a reduction in the maize rhizosphere. AMF inoculation decreased DTPA-extractable Cd, indicating lower Cd availability, especially in S. alfredii. This highlights the enhanced competitive uptake of soil Cd by S. alfredii. Additionally, AMF promoted beneficial bacterial genera, such as TM7a, Massilia, Sphingomonas, and Pedobacter, which supported maize under Cd stress. Key metabolites, including terpenoids, eicosanoids, linoleic acids, fatty acids, and flavones, were crucial in shaping the microbial community. These findings highlight the potential of AMF to facilitate safe maize cultivation and effective phytoremediation in moderately Cd-contaminated soils.