Bacillus velezensis SF-10 modulates the rhizosphere core microbiome by stimulating the probiotic community to control...

Tomato wilt disease, caused by Fusarium spp., is one of the most harmful soil-borne diseases globally. Biological control is an environmentally friendly and effective strategy, but its success largely depends on the type of bacterial strain used and its ability to regulate rhizosphere soil microorganisms. In this study, a new bacterium Bacillus velezensis SF-10 was from rhizosphere of healthy tomato plants grown in wilt-infested fields, which showed a high control effect of 74.14 % against wilt disease in tomato seedlings. The SF-10 can produce amylase, cellulase, siderophores, and IAA, and has demonstrated stable colonization via a constructed rifampicin resistance marker system. However, it is currently unknown how SF-10 inoculation regulates soil microbial communities and plant metabolites to achieve disease resistance, especially during the seedling stage. Here, we used amplicon sequencing and metabolite profiling revealed that B. velezensis SF-10 significantly altered the structure of the rhizosphere microbiota in plants challenged with the wilt pathogen. During this process, B. velezensis SF-10 recruits various beneficial soil bacteria, particularly Sphingomonas and Flavobacterium, to suppress F. oxysporum. These beneficial bacteria exhibited significant positive correlations with secondary metabolites such as total phenols, flavonoids, and lignin. In summary, B. velezensis SF-10 enhancing plant resistance by regulating the rhizosphere microbial community and increasing secondary metabolite content, providing valuable insights for the biological control of soil-borne diseases in vegetables.