Methyl jasmonate improves physiological and biochemical responses of Anchusa italica under salinity stress

Jasmonates are key signaling compounds in plant responses to biotic and abiotic stresses as well as in development. We studied the salt-tolerance capacity and the role of methyl jasmonate (MeJA) in alleviating NaCl-induced salt stress of Anchusa italica through evaluating its growth, physiological and biochemical attributes in a pot-culture. Accordingly, plants were exposed to the salinity concentrations of 1.86 (control), 5, 10 and 15 dS m−1 for 2 weeks, 24 h after foliar application of 0, 60 and 120 µM MeJA. Salt stress induced a significant reduction in leaf fresh weight, leaf area, leaf relative water content (RWC) and concentrations of chlorophyll a (Chl a), total chlorophyll (TChl), soluble sugars, total protein and K+, while an increase in proline, Na+ and Ca2+ contents. However, exogenous application of MeJA enhanced contents of Chl a, TChl, proline, soluble sugars, protein, K+ and Ca2+ while declined Na+ content in salt-stressed plants. In addition, pretreatment with 120 µM MeJA improved the growth attributes such as leaves and roots fresh weights, leaves and plant dry weights, leaf area and RWC. In summary, our results indicated that A. italica could tolerate the moderate levels of salinity (5 and 10 dS m−1). Also, foliar application of MeJA could reduce the adverse effects of salinity stress in A. italica. © 2020 SAAB