Genomic and Functional Characterization of Bacillus amyloliquefaciens H6: A Potent Fengycin-Producing Biocontrol...

Fusarium graminearum is a prominent pathogen responsible for global wheat scab, which not only leads to reduced yield and seed quality but also results in the production of diverse mycotoxins that persist on seeds, posing significant threats to both animal and human health. A bacterial strain, which exhibited a potent inhibitory effect on F. graminearum, was meticulously selected through dual culture and subsequently identified as Bacillus amyloliquefaciens H6 based on its morphological and physiological characteristics, as well as its whole-genome analysis. The antagonistic activity of H6 had been further studied antagonistic activity was further studied. Scanning electron microscopy and fluorescence microscopy revealed that the hypha in the inhibitory region was disrupted, resulting in contraction and deformation of the mycelium. Four out of seven lipopeptide extracts derived from the culture supernatant of B. amyloliquefaciens H6 demonstrated inhibitory effects on the growth of F. graminearum mycelium. MALDI-TOF-MS analysis revealed that the samples predominantly consisted of fengycin mixtures exhibiting diverse glycoside chains and configurations. The above results demonstrated that fengycin, produced by B. amyloliquefaciens H6, effectively inhibits F. graminearum. The biocontrol potential of this strain was further predicted by genomic analysis. The strain H6 exhibited significant potential for biological control in agriculture, making it a promising candidate for future applications.