University of Guilan Iranian Journal of Seed Sciences and Research 2476-3780 12 3 2025 09 23 Evaluation of seed priming with salycilic acid on salt stress tolerance during germination and seedling growth stages of tomato (Solanum lycopersicum L. cv. Brivio hybrid) Evaluation of seed priming with salycilic acid on salt stress tolerance during germination and seedling growth stages of tomato (Solanum lycopersicum L. cv. Brivio hybrid) 66 80 9428 10.22124/jms.2025.9428 FA Reza Rezvani Ph.D. Student of Crop Physiology Department of Plant Production, Faculty of Agriculture and Natural Resources, Gonbad Kavous University, Gonbad Kavous, Iran. Abbas Biabani University of Gonbad Kavoos Zahra Taghizadeh Tabari Ph.D. in Crop Ecology and Postdoctoral Researcher, Iran National Science Foundation (INSF), Tehran, Iran. Masoumeh Naeemi Assistant Professor, Department of Plant Production, Faculty of Agriculture and Natural Resources, Gonbad Kavous University, Gonbad Kavous, Iran. Journal Article 2025 10 23 The germination is crucial for the early growth and establishment of the plant and the seed priming technique, by inducing physiological and biochemical changes, prepares seed for effective germination prior to placement the planting medium. This study, conducted in 2025, aimed to assess the influence of salycilic acid pretreatment on the germination indices and growth parameters of tomato (Solanum lycopersicum L.) under salt stress. Two experiments, one in the laboratory and the other in a greenhouse, were performed using a factorial design based on a completely randomized design with three replications at the Faculty of Agriculture and Natural Resources, Gonbad Kavous University. The experimental factors included salicylic acid priming at four concentrations (0, 2, 2.5, and 3 mg/l-1) and salinity at five levels (0, 30, 60, 90, and 120 mM NaCl). The results of a 14-day germination test under laboratory conditions indicated that seed priming with salicylic acid under salt stress conditions, in comparison to the control, resulted in enhancements in germination and growth traits of tomato plants, including germination percentage and rate, seedling length, dry weight, seed vigor index, and the contents of chlorophyll a, b and total chlorophyll. The highest germination rate (8.22 seeds per day) and seedling vigor index (9.80) were observed in the treatment with 3 mg/l-1 salicylic acid under without saline conditions. In the greenhouse experiment, application of salicylic acid for five weeks after sowing tomato seeds in seedling trays enhanced growth traits, including plant dry weight and chlorophyll a, b, and total chlorophyll content. The interaction between salicylic acid and salinity indicated that the application of this compound, particularly at concentrations of 2.5 and 3 mg/l-1, mitigated the negative effects of salt stress on total chlorophyll content, such that no significant changes were observed at salinity levels up to 60 mM NaCl. In conclusion priming tomato seeds with salicylic acid, as a cost-effective, accessible, and practical approach, can enhance plant tolerance to salt stress and contribute to the sustainability of tomato production in saline soils, which account for approximately 25% of Iran's arable lands. The germination is crucial for the early growth and establishment of the plant and the seed priming technique, by inducing physiological and biochemical changes, prepares seed for effective germination prior to placement the planting medium. This study, conducted in 2025, aimed to assess the influence of salycilic acid pretreatment on the germination indices and growth parameters of tomato (Solanum lycopersicum L.) under salt stress. Two experiments, one in the laboratory and the other in a greenhouse, were performed using a factorial design based on a completely randomized design with three replications at the Faculty of Agriculture and Natural Resources, Gonbad Kavous University. The experimental factors included salicylic acid priming at four concentrations (0, 2, 2.5, and 3 mg/l-1) and salinity at five levels (0, 30, 60, 90, and 120 mM NaCl). The results of a 14-day germination test under laboratory conditions indicated that seed priming with salicylic acid under salt stress conditions, in comparison to the control, resulted in enhancements in germination and growth traits of tomato plants, including germination percentage and rate, seedling length, dry weight, seed vigor index, and the contents of chlorophyll a, b and total chlorophyll. The highest germination rate (8.22 seeds per day) and seedling vigor index (9.80) were observed in the treatment with 3 mg/l-1 salicylic acid under without saline conditions. In the greenhouse experiment, application of salicylic acid for five weeks after sowing tomato seeds in seedling trays enhanced growth traits, including plant dry weight and chlorophyll a, b, and total chlorophyll content. The interaction between salicylic acid and salinity indicated that the application of this compound, particularly at concentrations of 2.5 and 3 mg/l-1, mitigated the negative effects of salt stress on total chlorophyll content, such that no significant changes were observed at salinity levels up to 60 mM NaCl. In conclusion priming tomato seeds with salicylic acid, as a cost-effective, accessible, and practical approach, can enhance plant tolerance to salt stress and contribute to the sustainability of tomato production in saline soils, which account for approximately 25% of Iran's arable lands.