Biocontrol Potential of <i>Bacillus velezensis</i> <scp>ZF</scp> ‐10 Inhibiting Potato Virus Y and Promoting Growth of Tobacco Plant

ABSTRACT The viral disease caused by potato virus Y (PVY) poses a serious threat to tobacco plants worldwide. In this study, Bacillus velezensis ZF‐10, isolated from Panzhihua, China, exhibited an effective inhibitory effect against PVY. The presence of B. velezensis ZF‐10 significantly reduced the accumulation of PVY to 25.4% in plants and lowered the disease index to 15.23. Moreover, the infiltration of B. velezensis ZF‐10 on leaves of tobacco resulted in an increase in reactive oxygen species (ROS) and enhanced defence enzyme activity, leading to a decrease in malondialdehyde (MDA) accumulation and ultimately improving the tolerance of tobacco plants to PVY infection. Additionally, in a greenhouse environment, B. velezensis ZF‐10 promoted the growth of tobacco plants. Furthermore, B. velezensis ZF‐10 was found to exhibit activities such as ammonia production, cellulase, protease and siderophore production, and the ability to solubilise insoluble phosphates in soil. As a novel plant growth‐promoting bacterium (PGPB), B. velezensis ZF‐10 not only effectively suppressed the occurrence of PVY disease and enhanced tobacco growth but also demonstrated potent antifungal properties against various phytopathogens that cause diseases in tobacco plants and other crops. In conclusion, B. velezensis ZF‐10 is a potential biocontrol agent against PVY infection a supporter of plant growth for tobacco plant.