Foliar magnesium enhances rice salt tolerance by improving photosynthesis and regulating ion homeostasis

This study found that magnesium sulfate could enhance the salt tolerance of rice in coastal saline-alkali soils, whereas the effects vary significantly among different concentrations. Under 20 g L^-¹ of MgSO₄ treatment, rice leaves exhibited the highest net photosynthetic rate and total chlorophyll content, while the incidence of leaf tip wilt and the accumulation of toxic sodium ions (Na⁺) were minimized, resulting in the highest yield and total biomass. Therefore, 20 g L^-¹ of MgSO₄ is likely to be recommended as the optimal application concentration in saline-alkali areas.