Plants must cope with the stress conditions to survive. Plant growth promoting rhizobacteria can improve plant growth either directly or indirectly under stress conditions. However, the possible mechanisms remain unclear. Here we report that Bacillus megaterium strain A12 (BMA12) maintains hormonal and redox homeostasis and restores the photosynthetic efficacy of tomato plants through multiple mechanisms to survive under salinity stress conditions. Tomato plants were co-cultivated with BMA12 under saline conditions. The application of BMA12 significantly increased plant growth and photosynthetic capacity. BMA12 decreased production of ROS and ethylene but increased expression levels of selected genes responsible for repairing of damaged photosynthetic apparatus and maintenance of redox homeostasis. Furthermore, BMA12 significantly altered metabolic profile to restore perturbations of tomato plant physiology impaired with salinity stress. This study proves that BMA12 can be used in the conventional agriculture system in the salinity effected fields.

植物必须应付胁迫条件才能生存。促进根瘤菌生长的植物可以在胁迫条件下直接或间接改善植物的生长。但是，可能的机制仍不清楚。在这里我们报道巨大芽孢杆菌菌株A12（BMA12）维持激素和氧化还原稳态，并通过多种机制恢复番茄植物的光合功效，以在盐分胁迫条件下存活。在盐水条件下将番茄植物与BMA12共培养。BMA12的应用显着提高了植物的生长和光合能力。BMA12减少了ROS和乙烯的产生，但增加了负责修复受损的光合作用和维持氧化还原稳态的所选基因的表达水平。此外，BMA12显着改变了代谢特性，以恢复盐分胁迫损害的番茄植物生理的扰动。这项研究证明BMA12可以在盐分影响领域的常规农业系统中使用。