Benign Bacillus: decoding the genetic potential of native rhizosphere Bacillus spp. from rice, to induce plant growth and defense

Abstract

Three bacterial strains namely Bacillus velezensis Strain BIK2, B. cabrialesii Strain BIK3, and B. paralicheniformis Strain BIK4, were extracted from indigenous rice soils in India. These strains demonstrated potent efficacy against major pathogens while stimulating plant growth in rice. Their genomic analysis indicated a rich array of genes associated with secondary metabolite production, plant growth promotion, elicitation, and biocontrol activities. Biosynthetic gene clusters having different classes of secondary metabolites surfactin, macrolactinH, bacillaene, fengycin, difficidin, bacillibactin, and bacilysin were identified using various online tools. This information may be used as template for identification of novel bioactive antibacterial, antifungal, and organic plant growth-promoting compounds. Toxin-antitoxin gene pairs identified could play roles in their antibiotic resistance and prevention of harmful deletions in the bacterial genomes. CRISPRs detected in these isolates offer prospects for future gene editing and patenting endeavors. Notably, the genomic profiles of BIK2, BIK3, and BIK4 underscore their emphasis on plant growth enhancement, evident through the presence of genes facilitating nitrogen fixation, phosphate, and potassium solubilization, and siderophore production. This comprehensive genomic insight paves the way for tailored Bacillus strains, facilitating the industrial production of efficacious biomolecules for enhancing plant growth, controlling pathogens, and advancing pharmacological applications.

Keywords

• microbial secondary metabolites
• biostimulants
• bacillus velezensis
• bacillus cabrialesii
• bacillus paralicheniformis