Effect of Salicylic Acid on Vegetative and Physiological Parameters of Bitter Almond Seedlings under NaCl Stress

Almond trees have been grown in Iran for many years. Despite almond has been classified as salt semi-tolerant plant, poor quality of irrigation water in association with salt has reduced the yields of almond over recent years. Salicylic acid (SA) is responsible for inducing tolerance to a number of biotic and abiotic stresses. Thas, an experiment was conducted to study the effect of SA on salinity stress alleviation of bitter almond seedling. The experiment was set up as factorial experiment in completely randomized design with two factors including NaCl concentration (0, 40 or 80 mM) and SA at three levels (0, 0.5 or 1 mM). The results showed that salt stress decreased some vegetative growth parameters and relative water content and increased ion leakage and leaf proline content in almond seedlings. Application of SA improved vegetative growth parameters, decreased proline concentration, increased water relative content and leaf chlorophyll index. Improved stress indexes in SA- treated seedlings showed that applied of SA ameliorated the adverse effects of injury caused by salt stress.