Reduction of salinity effects caused by magnesium salts

This study explores the impact of salicylic acid (SA) on salt stress tolerance in two tomato varieties (Solanum lycopersicum), Saint-Pierre and Semillas de Alta Selecci n. The experiments were conducted under controlled and semi-controlled conditions, exposing seeds and seedlings to media enriched with MgCl₂ and MgSO₄ (50 and 100 mM), combined or not with salicylic acid (0.25 and 0.5 mM). The results reveal that the application of SA, particularly at 0.25 mM, significantly improves germination, morphological growth and physiological responses. In the presence of 50 mM MgSO₄, the germination rate reached 100% in Semillas de Alta Selecci n and 70% in Saint-Pierre, compared to 73% and 37% respectively under salt stress alone. AS also stimulated chlorophyll production and promoted proline accumulation, enhancing photosynthesis and stress tolerance. The combination of 0.25 mM AS and 50 mM MgSO₄ resulted in a significant increase in seedling height (+47.97% in Saint-Pierre and +46.41% in Semillas). These beneficial effects are less pronounced with 0.5 mM AS, indicating that a low concentration is more effective.