Enhancing Wheat Growth and Yield through Salicylic Acid-Mediated Regulation of Gas Exchange, Antioxidant Defense, and Osmoprotection under Salt Stress

Abstract

Salinity is a major challenge for agricultural productivity, adversely affecting crop growth and yield. In recent years, various techniques have been developed to increase crop tolerance to salinity, including seed priming. This study was carried out to assess the effects of salicylic acid (SA) priming (0-, 10- and 20-mM) in comparison with hydropriming on growth, physio-biochemical activities, and yield of two wheat varieties (AARI-11 and Ujala-15) under 0- and 170-mM sodium chloride (NaCl) toxicity. The exposure of wheat plants to NaCl led to a significant reduction in various growth factors, including fresh weight (40%), total chlorophyll (39%), stomatal conductance (42%), shoot Ca2+ (39%), and 1000-grain weight (34%). In contrast, salt stress triggered the activities of POD, SOD, CAT, glycine-betaine, phenolics, and proline. The application of 20 mM SA through seed priming was found to greatly improve the fresh root weight, chlorophyll b, POD activities, shoot Ca2+, and overall yield (up to 71, 66, 35, 57, and 44%, respectively) under salt stress. While hydropriming also enhanced wheat tolerance to salinity.

Contribution of Antioxidant System Components to the Long-Term Physiological and Protective Effect of Salicylic Acid on Wheat under Salinity Conditions

“…Salicylic acid (SA), a phytohormone of phenolic nature, plays a fundamental role in regulating plant growth and development. A review of the literature data confirms the effectiveness of seed priming with SA in increasing the resistance of wheat to various stresses [ 4 , 6 , 12 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 ]. In previous research, we determined that a concentration of 50 µM SA had a stimulating and protective effect on wheat plants [ 26 ].…”

Putting Biochar in Action: A Black Gold for Efficient Mitigation of Salinity Stress in Plants. Review and Future Directions

“…Saline conditions also increase the production of reactive oxygen species (ROS) that disrupt the cell redox balance and cause damage to essential molecules and cell organelles . However, plants have excellent systems, including a reduction in the uptake of toxic ions, the compartment of toxic ions in vacuoles, the production of various osmolytes, and increased enzymatic and nonenzymatic antioxidant activities, that can counter the toxic effects of salinity . Nonetheless, when salinity stress is severe, plants cannot protect themselves from the damaging effects of salinity.…”

Synergistic Effects of Rhizobacteria and Salicylic Acid on Maize Salt-Stress Tolerance

“…Additionally, detrimental effects of salinity increase the production of reactive oxygen species (ROS) by disrupting the redox balance of plant cells, causing damage to essential molecules and organelles within the cells [16]. Plants have a natural defense system that includes limiting the uptake of toxic ions, storing toxic ions in vacuoles, producing osmoprotective compounds, and regulating stomata to maintain water levels in salt-stressed plants generating both enzyme-based and non-enzyme-based antioxidants [17][18][19][20]. However, when salinity stress is severe, plants cannot protect themselves as effectively, and are more susceptible to the damage caused by salt.…”

“…Exogenous application of SA has demonstrated tremendous potential to improve salt tolerance in various plant species [24][25][26]. By regulating stomatal behavior and hormonal status and increasing osmolytes, antioxidants, proteins, and secondary metabolites, SA treatment alleviates the harmful effects of salinity [20,27]. Moreover, it can function as an antioxidant, scavenging accumulated ROS [28].…”