Title: Salicylic acid supply alleviates salt stress in durum wheat

Abstract

Salicylic acid (SA) is an important signal molecule in alleviating the negative impact of abiotic stress, including salt stress, on several crops especially durum wheat. This study highlights the effect of SA exogenous addition (0, 0.7, 1.2 and 2.7 mmol), on morphological and physiological attributes of five durum wheat varieties (‘Karim’, Maali’, Salim’ ‘INRAT 100’, and ‘Dhahbi’) under salt stress (100, 200 and 300 mmol NaCl) compared to control (0 mmol NaCl). A pot experiment was contemplated to assess the foliar supply benefits of this molecule on morpho-physiological attributes of durum wheat, using the same concentration under stressed and unstressed conditions. Our results depict that salt stress inflicted marked reductions physiologic and phenotypic performances. The supply of SA stimulated the plant height, leaf area, leaf number, tall number and chlorophyll content especially in stressed conditions. This analysis also allowed the identification of genotypes exhibiting various levels of tolerance to NaCl with SA addition under salt conditions. In fact, among the five genotypes Salim and INRAT 100 were the most performed ones. However, when the plants were grown in severe stress (300 mmol NaCl), no significance difference were noted between SA-treated and non-SA-treated plants. Therefore, results showed suggest that exogenous SA can effectively alleviate the adverse effect of moderate salt stress on durum wheat growth and development.