Salicylic acid (SA) is a plant signaling molecule, which regulates various metabolic processes and involves in eliciting specific responses against abiotic/biotic stresses. Present study investigated the effect of SA on seed germination and seedling growth of salt stressed wheat. Wheat seeds were primed with water and two concentrations of SA (0.5 and 1.0 mM) for 12 h. For In-vitro experiment, seeds were soaked in 0, 50 and 100 mM NaCl solutions and seed germination and seedling growth parameters were studied. Primed seeds (both 0.5 and 1.0 mM SA) significantly improved seed germination, rate of germination, total chlorophyll, soluble sugars, proteins and phenolic content, as compared to non-primed and hydro-primed controls. For greenhouse experiment, hydro-primed (control) and SA primed (0.5 and 1.0 mM) seeds were grown in plastic pots and irrigated with 0 and 100 mM NaCl for 4 weeks. Plants emerged from SA primed seeds showed better response to salinity in which higher contents of photosynthetic pigments, soluble sugars, proteins and phenols contributed to enhanced growth and biomass production, as compare to control plants. Seed priming with 1.0 mM SA was found most effective to protect plants from damaging effects of salinity as compare to hydro-priming and 0.5 mM SA priming. Therefore, it is suggested that the priming of seeds with 1.0 mM SA can be adopted as a strategy to enhance wheat growth especially in salt affected soils.

Secondary metabolites, such as phenolic compounds, play an important role in alleviating salinity-induced negative effects in plants. The present study focused on seed priming and foliar application of a potent phenolic compound, coumarin, to induce salinity tolerance in Sorghum bicolor var. SS-77. Based on pilot experiment, 100 mg L−1 concentration of coumarin was applied to mitigate the negative effects of salinity on Sorghum, grown at 0, 100, and 200 mM NaCl under netted greenhouse conditions. Coumarin was applied to each salinity treatment in four different ways (i) non-primed control (NP), (ii) seed priming (COP), (iii) foliar application (COF), and (iv) a combination of seed priming and foliar application (COPF). Salinity stress significantly reduced the plant growth, biochemical attributes, and photosynthetic efficiency of Sorghum, whereas coumarin treatments (COP, COF, and COPF) showed a significant increase (P< 0.01) in above-mentioned parameters at all salinities. Among all, the combined treatment (COPF) showed maximum increase in growth, biochemicals, photosynthetic pigments, antioxidant enzymes, and photosynthetic efficiency parameters. Therefore, it is suggested that a combination of seed priming and foliar spray of 10 mg L−1 coumarin is more suitable than their individual applications. It is an environment friendly and economically feasible approach that will be used to improve salinity tolerance of Sorghum and helpful to get considerable biomass from saline degraded lands to fulfill food, fodder, and energy demands of the ever-growing population.

No abstract

No abstract