Mitigation of salinity stress effects on Vicia faba L. growth and productivity using proline and salicylic acid foliar application

High soil salinity causes a negative impact on plant growth and lowers crop yields. Thus, pot experiments were conducted to investigate the impact of foliar application of salicylic acid (SA) and proline (Pro), separately and combined, on enhancing salinity tolerance in broad beans. Salinity stress (4.69 ds/m and 6.25 ds/m) significantly reduced plant growth (plant height, leaf area, number of leaf/plant, plant dry weight), chlorophyll pigment content (chlorophyll a, b or total), relative water content, K/Na ratio, seed yield per plant, and N, P, K, and crude protein content in broad bean seeds. Foliar application of Pro and SA, either individually or in combination, enhanced plant growth parameters, chlorophyll pigment content, endogenous proline levels, phenol content, and the activities of antioxidant enzymes [antioxidant enzymes including catalase (CAT), peroxidase (POD) and superoxide dismutase (SOD)]. Additionally, these treatments enhanced plant seed yield, N, P, K, and crude protein levels in the seeds. The combined foliar application of Pro and SA was more effective in mitigating salinity stress’s harmful effects than using either substance alone. These findings indicate that foliar application of SA and Pro, either individually or in combination, alleviated the adverse effects of salinity on broad beans, with the combined application proving to be the most effective.