Inoculation with Bacillus cereus DW019 Modulates Growth, Yield and Rhizospheric Microbial Community of Cherry Tomato

Abstract

Plant growth-promoting rhizobacteria (PGPR) play an important role in promoting plant growth and increasing crop yield. Bacillus cereus DW019, which was previously isolated from an ion-absorbed rare-earth ore of Ganzhou in Southeastern China, has been considered as a PGPR due to its production of indole-3-acetic acid (IAA), ammonia and siderophore, but its promoting effect on plants remains poorly understood. In this study, autoclaved dead cells and viable cells of Bacillus cereus DW019 at different concentrations were inoculated into pot-cultivated cherry tomato (Lycopersicon esculentum) to investigate the promoting effect on plant growth and yield. A total of 70 days after inoculation, the plants and fruits of cherry tomato were harvested, and their growth indicators, yields, and nutrients were measured. The results showed that biomass, stem thickness, plant height and root length were significantly promoted and that the vitamin C, soluble sugar and soluble protein were significantly increased. Inoculation with Bacillus cereus also modulated the rhizospheric microbial community diversity and structure, especially the proportions of Proteobacteria and Actinobacteriota, which in turn improved the plant height, fresh weight, nutritional quality and rhizosphere soil bacterial diversity of cherry tomato. All the findings suggest that Bacillus cereus DW019 is beneficial to the growth of crops and improves the yield of cherry tomato, suggesting that Bacillus cereus DW019 could be developed into a potential biofertilizer to be used as an agricultural inoculant to increase crop yield and improve the soil ecosystem.