Intercropping, the co-cultivation of two or more plant species in the same field, has several advantages over growing only one plant species, however, the role of plant-microbe interactions in such a setup is poorly understood. To investigate the influence of rhizosphere colonization by plant growth-promoting rhizobacteria (PGPR) in an intercropping system, a model legume-cereal intercropping system involving maize (Zea mays) and pigeon pea (Cajanus cajan) was assessed for colonization using three different bacterial strains Enterobacter sp. C1D, Pseudomonas sp. G22, Rhizobium sp. IC3109. Cross colonization experiments suggested bacterial movement from one plant species to another in the presence/absence of a mesh barrier, implicating the role of intercrop root exudates. In vitro assays and plant inoculation studies displayed that Enterobacter sp. C1D had a preference for monocropped plants while Rhizobium sp. IC3109 to intercropped plants and Pseudomonas sp. G22 was evenly colonized in both conditions. Organic acids like fumarate, malate, and succinate, as analyzed by LC/MS/MS (MRM), were found to be prominent in monocropped plant root exudates, while co-cultivation resulted in a decrease of the exudation of these metabolites. The PGPR strains showed differential behavioral responses in terms of chemotaxis and biofilm formation towards root exudates of intercropped and monocropped plants. Overall, our study provides pieces of evidence that co-cultivation of legume and cereal plants leads to the variation in root exudates and the response of plant beneficial bacteria.

间作，即在同一领域中两种或多种植物的共培养，与仅种植一种植物相比具有多个优势，但是，人们对植物-微生物相互作用在这种设置中的作用了解甚少。为了研究在间作系统中植物促生根瘤菌（PGPR）对根际定植的影响，使用三种不同细菌菌株评估了一个由玉米（Zea mays）和木豆（Cajanus cajan）组成的模型豆科谷物间作系统的定殖情况。肠杆菌属。C1D，假单胞菌属。G22，根瘤菌sp。IC3109。交叉定殖实验表明，在存在/不存在网状屏障的情况下，细菌从一种植物移到另一种，这暗示了作物间根系分泌物的作用。体外测定和植物接种研究表明肠杆菌属。C1D优先选择单季作物，而根瘤菌则优先。IC3109适用于间作植物和假单胞菌sp。在两种情况下，G22均被定殖。LC / MS / MS（MRM）分析表明，富马酸酯，苹果酸和琥珀酸酯等有机酸在单季种植的植物根系分泌物中尤为突出，而共培养导致这些代谢物的渗出减少。PGPR菌株在间作和单作植物的根系分泌物的趋化性和生物膜形成方面表现出不同的行为响应。总体而言，我们的研究提供了一些证据，表明豆类和谷类植物的共培养会导致根系分泌物的变化和植物有益细菌的反应。