Seed Priming with Salicylic Acid Alleviates Salt Stress Toxicity in Barley by Suppressing ROS Accumulation and Improving Antioxidant Defense Systems, Compared to Halo- and Gibberellin Priming

Plants are highly sensitive to various environmental stresses, which can hinder their growth and reduce yields. In this study, we investigated the potential of seed priming with salicylic acid (SA), gibberellic acid (GA₃), and sodium chloride (NaCl) to mitigate the adverse effects of salinity stress in <i>Hordeum vulgare</i> at the germination and early seedling stages. Exposing <i>H. vulgare</i> seeds to salt stress reduced the final germination percentage and seedling shoot and root growth. Interestingly, all seed treatments significantly improved salt-induced responses, with GA₃ being more effective in terms of germination performance, plant growth, and photosynthesis. SA priming exhibited promising effects on antioxidant defense mechanisms, proline, sugar, and ascorbic acid production. Notably, SA priming also suppressed reactive oxygen species accumulation and prevented lipid peroxidation. These findings highlight the ability of SA to manage crosstalk within the seed, coordinating many regulatory processes to support plant adaptation to salinity stress.