Plant growth-promoting bacteria delayed wilting and improved tomato yield when grown under water stress condition

Drought is a major setback to global agriculture. To achieve sustainable agriculture, water stress needs to be effectively managed. Tomato seedlings were screened using Host-Mediated Artificial Selection approach to select microbiota that can confer tolerance to water stress. Rhizospheric bacteria identified from the microbiota were assayed in vitro and in a greenhouse for stress tolerance and tomato growth promotion. The study was conducted in triplicates using a completely randomized design. Results from the study revealed that tomato plants inoculated with microbiota under water stress delayed wilting from rounds 1 to 4 of planting than the control for 3, 5, 6, and 8 days, respectively. Of all the bacterial species isolated from each round, only four strains of Bacillus genus survived till the fourth round. These organisms exhibited stress tolerance and growth-promoting characteristics in vitro. Under stressed soil, tomato plants treated with microbiota (141 g) increased (>) fruit weight than Bacillus cereus AN14 (123 g) > Bacillus thuringiensis AN10 (104 g) > B. sp. AN22 (98 g) > B. sp. ANP (91 g) and the control (77 g), respectively. These inoculants were effective in promoting tomato growth and yield of tomatoes under water stress.