Screening native Bacillus strains as potential biological control agents against ginger bacterial wilt and for promoting plant growth

• DOI: 10.1016/j.biocontrol.2024.105510
• Publication Date: 2024-04-16T15:20:58Z
• Authors: Wenyan Cui; Jiajia Zhang; Wenjia Wang; Xiaoyun Wu; Xiyan Luo; Yuan Zou; Kunxiu Chen; Pengjie He
• Keywords: Bacterial wilt; Ralstonia solanacearum; Wilt disease; Biopreservation

Bacterial wilt, caused by Ralstonia solanacearum, is a destructive disease that causes significant loss in ginger productivity. This notoriously difficult to control chemical measures, prompting the exploration of biological as more sustainable and effective alternative strategy. In our research, we aimed develop microbial agents combat R. solanacearum-induced bacterial wilt ginger. Initially, 307 Bacillus-like strains were isolated from rhizosphere soil. Among these, ten exhibited antibacterial activity after extensive vitro screening, with isolate F18 being most effective. Further tests co-culture assay revealed six isolates, notably L70, significantly reduced pathogen's fitness. To further assess their effectiveness, isolates L3, L72, L73, F18, HC-5, L70 then subjected hydroponics assay, where they substantially lowered incidence seedlings, especially L73. These three identified Bacillus velezensis, exhibiting beneficial traits such IAA production, siderophore secretion, phosphate potassium solubilization. Additionally, also harbored genes related production dipeptide bacilysin polyketides macrolactin, bacillaene difficidin. greenhouse experiments, these B. velezensis strains, particularly demonstrated remarkable efficacy controlling wilt. Tubers soaked biocontrol showed severity pathogen population. Moreover, treatments promoted growth, tuber fresh weight, HC-5 showing greatest improvement. Conclusively, this study suggests highly efficient strategy for biologically emerging promising agents.