Isolation and Identification of Endophytic Bacterium B5 from <i>Mentha haplocalyx</i> Briq. and Its Biocontrol Mechanisms Against <i>Alternaria alternata</i>-Induced Tobacco Brown Spot.

ABSTRACT: The fungus Alternaria alternata, which causes tobacco brown spot disease, poses a serious threat to the tobacco industry. Beneficial microorganisms and their secondary metabolites have emerged as a promising green strategy for disease management. This study recovered 16 endophytic bacterial strains from Mentha haplocalyx Briq., a therapeutic herb. The study revealed that strain B5, with an inhibition rate of 82.76%, exhibited the highest antifungal activity against A. alternata. This strain exhibited broad-spectrum antifungal activity, with inhibition rates ranging from 66.34% to 87.23%. Phylogenetic analysis of 16S rDNA and gyrA gene sequences identified it as Bacillus velezensis (GenBank: PV168970 and PV173738). Further characterization revealed that st

SUBMITTER: Qin Q 

PROVIDER: S-EPMC12194751 | biostudies-literature | 2025 Jun

REPOSITORIES: biostudies-literature