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Seed‐borne pathogens can inhabit the rhizosphere and infect the plant after germination. The rhizosphere microbiome plays critical roles in defending against seed‐borne pathogens. However, the assembly of a core rhizosphere microbiome to suppress seed‐borne pathogens is unknown. Here, the root‐associated microbiome is infested with seed‐borne Fusarium in sterile environment, while the root‐associated microbiome is not infested when it interacts with the native soil microbiome across maize cultivars, suggesting that a core rhizosphere microbiome assembles to suppress seed‐borne Fusarium. Two strategies of progressive dilution and rhizodepositional attraction are applied to identify the core rhizobacteria. A synthetic microbiota (SynM) is constructed using the isolates of the core rhizobacteria and optimized according to superior community stability and Fusarium‐suppression capability, which surpasses the single strain and randomly formed microbiota. The optimized SynM (OptSynM) presents a distinctive cooperative pattern in which a key strain harbors the Fusarium suppression function by synthesizing the antagonistic substance fengycin, while other members intensify the functional performance by promoting the growth and the expression of the antagonistic and plant‐growth‐promoting related genes of the key strain. This study demonstrates innovative approaches to construct stable and minimal microbiota for sustainable agriculture and proposes a unique cooperative pattern to sustain community stability and functionality. [ABSTRACT FROM AUTHOR]

Chemotaxis, the ability of motile bacteria to direct their movement in gradients of attractants and repellents, plays an important role during the rhizosphere colonization by rhizobacteria. The rhizosphere is a unique niche for plant–microbe interactions. Root exudates are highly complex mixtures of chemoeffectors composed of hundreds of different compounds. Chemotaxis towards root exudates initiates rhizobacteria recruitment and the establishment of bacteria–root interactions. Over the last years, important progress has been made in the identification of root exudate components that play key roles in the colonization process, as well as in the identification of the cognate chemoreceptors. In the first part of this review, we summarized the roles of representative chemoeffectors that induce chemotaxis in typical rhizobacteria and discussed the structure and function of rhizobacterial chemoreceptors. In the second part we reviewed findings on how rhizobacterial chemotaxis and other root–microbe interactions promote the establishment of beneficial rhizobacteria-plant interactions leading to plant growth promotion and protection of plant health. In the last part we identified the existing gaps in the knowledge and discussed future research efforts that are necessary to close them. [ABSTRACT FROM AUTHOR]