Improving Tolerance of Tomato Plants to NaCl Toxicity for Agricultural Sustainability

Plant growth and yield are affected by salinity. Symbiotic interactions between plants and endophytic fungi are a promising approach to promoting crop growth under salt-stress conditions. Here, the tolerance of the endophytic fungus Pleosporaceae sp. was verified under diverse NaCl levels (0, 50, 100, 150, and 200 mM). Subsequently, Pleosporaceae sp. production of indole acetic acid (IAA) was assessed in vitro at various salinity levels (0, 50, 100, 150, and 200 mM). Additionally, the effect of Pleosporaceae sp. inoculation on germination, growth, and biochemical characteristics of tomato (Solanum lycopersicum L.) under five levels of salinity (0, 20, 50, 100, 150, and 200 mM NaCl) was investigated. The results indicated that Pleosporaceae sp. exhibited strong salt tolerance and produced approximately 138.6 ± 0.7 μg/ml of IAA under 100 mM NaCl. Moreover, the results showed that this symbiotic fungus significantly enhanced germination and growth under salinity. Pleosporaceae sp. also significantly improved proline and sugar accumulation under salt treatment. This study suggests that the endophytic fungus Pleosporaceae sp. can be employed to mitigate sodium chloride-induced stress in plants, thereby improving plant growth and productivity.