EFFECT OF FOLIAR APPLICATIONS OF SALICYLIC ACID AND POTASSIUM SILICATE ON TOLERANCE OF WHEAT PLANTS TO SOIL SALINITY

A pot experiment was carried out under greenhouse conditions to investigate the effect of salicylic acid (SA) and potassium silicate (KSi) foliar applications in alleviating the salt stress of soil salinity (S) on wheat plants. Three soil salinity levels i.e., 3, 6 and 12 dS/m were developed. Foliar spray of salicylic acid with rates of 0, 50,100 and 150 mg/L were applied. Also, K- silicate were applied exogenously with sprayer using two levels 0 and 2 ml/L. Plants were harvested at maturity stage, then yield components and nutrients content of wheat grains and straw were determined. Salinity stress (S) significantly reduced yield components i.e., grain and straw yields of wheat plants as well as weight of 1000 grains with varying degrees. However, salinity decreased grains and straw contents of potassium (%), calcium (%) and phosphorus (%) while; sodium (%) and chloride (%) were increased positively with soil salinity.Plants treated with salicylic acid (SA) showed increasing yield components of wheat plants. Also, remarkable increases in potassium (%) calcium (%) and phosphorus (%) of grains and straw were noticed in plants sprayed with salicylic acid (SA). Meanwhile, salicylic acid application caused reduction in sodium (%) and chloride (%) in both of grains and straw. Moreover, K-silicate (KSi) application significantly improved yield components of wheat and also increased their contents of potassium (%), calcium (%) and phosphorus (%). While, adverse effects were shown with respect to the contents of sodium (%) and chloride (%) for both of grains and straw. In general, both of salicylic acid and K-silicate have enhancement role in increasing tolerance of wheat plants to salinity.