Unveiling the potential of silicon as seed priming agent to improve the tolerance in alfalfa against salinity stress

Alfalfa (Medicago sativa L.) is a perennial crop which is primarily cultivated as livestock feed worldwide. Among abiotic stresses, salinity affects its productivity by inhibiting key physiological processes, including photosynthesis, nutrient uptake, and water relations, ultimately reducing plant growth. A pot experiment was conducted during the Rabi season of 2023 to improve the salinity tolerance in alfalfa by silicon (Si) application. The treatments comprised three salinity levels [Control (S0), 5 dS m-1 (S1) and 10 dS m-1 (S2)] and four seed priming levels [Control (NP), hydropriming (HP), 2 mM Si (Si2) and 4 mM Si (Si4) solution] replicated thrice in a completely randomized design (CRD) with factorial arrangements. The morphological parameters, physiological parameters and quality parameters were collected and subjected to Fisher’s analysis of variance method for analysis, and the means of treatment were analyzed by the Tukey's HSD at 5% probability level. The results indicated that priming treatment with Si4 significantly influenced various growth, yield and quality parameters including maximum plant height, fresh fodder yield, dry matter yield, acid detergent fiber and neutral detergent fiber. The study concluded that seed priming with Si4 solution improved growth, yield and quality parameters of alfalfa up to 10 dS m-1 salinity stress. Thus, application of Si can facilitate the plants to continue the normal growth and development even under episode of salinity stress.