Restored Photosystem I and II Functional Integrity Largely Accounts for the Mitigation of Salinity Impact on the Facultative Halophyte Sulla Carnosa when Inoculated with Bacillus Subtilis

Soil salinization is a major abiotic stress that impairs plant growth and damages the photosynthetic apparatus. Plant growth promoting rhizobacteria (PGPR) are known to enhance plant tolerance to salinity, despite their mechanistic effects on photosynthesis remain unclear. Therefore, this study investigates the effects of Bacillus subtilis inoculation on the photosynthetic activity of Sulla carnosa under salt stress, with a focus on the functional performance of photosystems I and II. Seeds were either inoculated or not and grown in sterilized soil for one month, before exposure to 0 or 200 mM NaCl salinity for an additional month. Salinity severely reduced shoot and root dry weights by 32