1PHD candidate of Plant Physiology, Department of Biology, Faculty of Science, Bu-Ali Sina university, Hamadan, Iran
2Prof. of Plant Physiology, Department of Biology, Faculty of Science, Bu-Ali Sina university, Hamadan, Iran
Creeping savory (Satureja spicigera (C. Koch) Boiss.) is a wild edible and medicinal plant that is use in food industry and preparation of herbal drugs. To investigate the effects of Nano-selenium on photosynthetic pigments, antioxidant enzymes, osmolytes, and relative water contents in S. spicigera under NaCl stress conditions, a factorial experiment was conducted at the greenhouse of the Kermanshah Research Center of Agricultural and Natural Resources, Iran, based on a Completely Randomized Design (CRD). The experiment was conducted in 2019 and each experimental unit had 3 replications in one treatment. Factor A included four levels of NaCl (0-50-100-150 mM NaCl) and Factor B included two levels of Nano-selenium (control and 50 PPM). The results showed that there are significant differences between the different NaCl treatments for all studied traits (P<0.01). Also significant differences were observed between Nse treatments for SOD enzymatic activity and RWC (P<0.01) and for protein content, Chl b and enzymatic activities of POD and CAT (P<0.01). The interaction effect of salinity × NSe was significant for all studied traits except Chl b. Increasing salinity levels caused a significant reduction in relative water content, chlorophyll a, b, total chlorophyll, and carotenoid content. Salinity drastically enhanced the antioxidant activities of superoxide dismutase, peroxidase, and catalase. Also, salinity increased cell proline content. Foliar application of NSe (50 PPM) decreased chlorophyll b, proline content, and antioxidant activity of super oxide dismutase but improved antioxidant activities of peroxidase and catalase and enhanced chlorophyll an and carotenoid content under salt stress conditions. Also, NSe decreased protein content in moderate salt stress conditions (50 to 100 mM NaCl) but increased it under sever salinity stress (150 mM NaCl). NSe reduced the destructive effects of salinity on physiological and biochemical characteristics in creeping savory. 50 PPm Nse, has negative effects on the Chl a, carotenoid, total chlorophyll, soluble proteins, and RWC at the low NaCl stress conditions but it improved these traits in high NaCl stress conditions. Appropriate concentrations of Nano-selenium promote plant growth and help plant resistance to stresses, but high concentrations may induce oxidative stress and reduce plant growth.