Ameliorating Effect of Salicylic Acid on Physiological and Biochemical Characteristics of Satureja spicigera (C. Koch) Boiss. under NaCl Stress

Creeping savory is a wild plant that is used for comestible consumption, preparation of beverages, and production of sanitary ware and herbal drugs. To investigate the effects of salinity stress and salicylic acid on antioxidant enzymes, photosynthetic pigments, relative water content, proline, and soluble protein content in S. spicigera a factorial experiment was conducted based on a Completely Randomized Design (CRD) and three replications. The experiment was implemented at the greenhouse of Agriculture and Natural Resources Research and Education Center of Kermanshah, Iran (2019). Experimental treatments were four levels of salinity (0-50-100-150 mM NaCl) and two levels of salicylic acid (0 and 2 mM). Results showed that increasing salinity levels caused a significant reduction in relative water content, leaf fresh weight, leaf dry weight, chlorophyll a, chlorophyll b, total chlorophyll, and carotenoid content. Salinity drastically enhanced the antioxidant activities (SOD, POD, and CAT), and cell proline content. Salicylic acid considerably decreased proline content under salt stress conditions, but improved antioxidant activities of SOD, POD, and CAT, and enhanced chlorophyll a, chlorophyll b, total chlorophyll, carotenoid content, protein content, relative water content, and leaf fresh weight under salt stress. Salicylic acid reduced the destructive effect of salinity on some morphological, physiological, and biochemical characteristics in creeping savory.