Complete genome analysis and antimicrobial mechanism of <i>Bacillus velezensis</i> GX0002980 reveals its biocontrol potential against mango anthracnose disease

Post-harvest anthracnose significantly affects the yield and quality of mangoes. In this study, an antagonist bacterium, GX0002980, with strong inhibitory effect against <i>Colletotrichum gloesporioides</i>, the pathogen of mango anthracnose, was isolated from the rhizosphere soil of plants. Based on morphological characteristics, physiological and biochemical tests, and 16S rRNA gene and <i>gyrB</i> gene sequencing analysis, the strain was identified as <i>Bacillus velezensis</i>. Strain GX0002980 exhibits broad-spectrum antibacterial capabilities, and its volatile substances and sterile fermentation filtrate also demonstrate antagonistic effects against <i>C. gloesporioides</i>. This strain can produce antimicrobial substances that inhibit pathogen growth, such as amylase, cellulase, protease, pectinase, and siderophores, and has plant-growth-promoting characteristics, such as nitrogen fixation, NH₃ production, and phosphate solubilization. Whole-genome sequencing results show that the genome size of GX0002980 is 3,907,381 bp with a guanine and cytosine content of 47.44%. The antiSMASH analysis predicts 14 antimicrobial biosynthesis gene clusters within the GX0002980 genome, including surfactin, fengycin, bacilysin, macrolactin H, bacillaene, difficidin, and bacillibactin. Liquid chromatography-mass spectrometry analysis revealed that the antimicrobial active substances secreted by GX0002980 include surfactin, bacilysin, butirosin A, and more. Strain GX0002980 has an <i>in vitro</i> control efficiency of 52% against mango anthracnose, and it can effectively suppress the occurrence of post-harvest diseases in mangoes, extending their storage time. In conclusion, <i>B. velezensis</i> GX0002980 possesses multiple biocontrol mechanisms and has potential for application in the biological control of mango anthracnose.IMPORTANCE<i>Bacillus velezensis</i> GX0002980 showed biocontrol potential against <i>Colletotrichum gloesporioides</i>, a causative agent of mango anthracnose. <i>B. velezensis</i> GX0002980 produces a variety of secondary metabolites with antibacterial properties. Whole-genome sequencing revealed potential active metabolite synthesis gene clusters of <i>B. velezensis</i> GX0002980. <i>B. velezensis</i> GX0002980 has a significant effect on the control of post-harvest disease in mango fruits.