A Novel Rhizospheric Bacterium: Bacillus velezensis NKMV-3 as a Biocontrol Agent Against Alternaria Leaf Blight in Tomato.

A novel strain of Bacillus isolated from rhizosphere has shown to be an excellent biocontrol agent against various plant pathogens. In this study, a first report of a Bacillus strain NKMV-3 which effectively controls Alternaria solani, which cause the early blight disease in tomato. Based on the cultural and molecular sequencing of 16S rRNA gene sequence, the identity of the strain was confirmed as Bacillus velezensis NKMV-3. The presence of the lipopeptide which are antibiotic synthesis genes, namely iturin C, surfactin A and fengycin B and D, was confirmed through gene amplification. In addition, lipopeptides were also confirmed through liquid chromatography. The extract showed inhibitory effect against A. solani in vitro and detached tomato leaf assays. Bacillus velezensis strain NKMV-3-based formulations may provide an effective solution in controlling early blight disease in tomato and other crops.