Legume/cereal intercropping is an example of classic nitrogen-efficient planting that can effectively improve crop yield and nutrient-utilization efficiency. However, the interaction between rhizosphere microorganisms and rhizodeposition and the related ecological mechanisms remain unclear. We conducted a pot experiment using ¹³CO₂ continuous labeling, DNA stable isotope probe technology, high-throughput sequencing, and the carbon-nitrogen-phosphorus functional gene chip to effectively track rhizosphere-deposited C and compare the microorganisms that utilize this C pool in the rhizosphere of a soybean/maize intercropping system at 21 days after labeling. The relative abundance of Caldalkalibacillus and Nesterenkonia that use rhizosphere-deposited C was significantly higher in the soybean/maize intercropping system than in monocropped soybean, but there were no significant differences between intercropped and monocropped maize. The soybean/maize intercropping system altered the composition of the microbial community that utilizes rhizosphere-deposited C and reduced the community richness. Moreover, intercropping improved the expression of functional genes associated with carbon fixation (acsH and exg) and nitrous oxide reduction (nosZ1). Overall, by tracking the flow of C from plant photosynthetic products to root exudates, our research provides new insights into identifying the microbial communities that assimilate and deposit carbon in soil.

豆类/谷物间作是经典的氮高效种植的一个例子，可以有效提高作物产量和养分利用效率。然而，根际微生物与根际沉积之间的相互作用以及相关的生态机制仍不清楚。我们利用 ¹³ CO ₂ 连续标记、DNA稳定同位素探针技术、高通量测序以及碳氮磷功能基因芯片进行盆栽实验，有效追踪根际-沉积 C 并比较标记后 21 天在大豆/玉米间作系统根际利用该 C 库的微生物。大豆/玉米间作系统中利用根际沉积碳的 Caldalkalibacillus 和 Nesterenkonia 的相对丰度显着高于单作大豆，但间作玉米和单作玉米之间没有显着差异。大豆/玉米间作系统改变了利用根际沉积碳的微生物群落的组成，并降低了群落丰富度。此外，间作提高了与碳固定（acsH和exg）和一氧化二氮还原（nosZ1）相关的功能基因的表达。总体而言，通过跟踪碳从植物光合产物到根系分泌物的流动，我们的研究为识别土壤中同化和沉积碳的微生物群落提供了新的见解。