Alleviation of Salinity Stress in Spring Wheat by Hormonal Priming with ABA, Salicylic Acid and Ascorbic Acid

Effects of hormonal priming with abscisic acid (ABA), salicylic acid (SA), or ascorbic acid on wheat (Triticum aestivum cv. Auqab 2000) germination and seedling growth under normal (4 dS/ cm) and saline (15 dS/ cm) conditions were studied to determine their usefulness in increasing relative salt-tolerance. During germination test, most of treatments were effective in improving germination and seedling vigor of wheat during salinity stress. Seeds primed with 50 ppm ascorbic acid and 50 ppm SA not only improved final germination count but also reduced the germination time under saline conditions. Seedling raised from primed seeds with 50 ppm SA followed by 50 ppm ascorbic acid had significantly higher lengths and fresh and dry weight of shoot than other treated or non-primed seeds under non-saline and saline conditions. But all hormonal priming treatments decreased the electrolyte leakage of steep water as compared to that of non-primed seeds even after 12 h of soaking. Hormonal priming with 50 ppm SA induced maximum decrease in electrolyte leakage, while an increase in electrolyte leakage was observed by 10 ppm ABA and 100 ppm ascorbic acid. It is concluded that hormonal priming has reduced the severity of the effect of salinity but the amelioration was better due to 50 ppm SA and 50 ppm ascorbic acid treatments as these showed best results on seedling growth, fresh and dry weights under non-saline and saline conditions whereas hormonal priming with ABA as not effective in inducing salt tolerance under present experimental material and conditions.