Effect of salinity stress on some morphology and physiology indices of Damask Rose ‎Kashan genotype ‎

To investigate the effect of NaCl salinity (0, 4, 8 and 12 dS m-1) on some morpho-physiological indices of Rosa damascenea Kashan genotype, a factorial pot experiment was designed based on randomized complete block design with four replications and three pots per replication (with total of 48 pots) on open air countineued for two years, and results of the second year data are reported. The results showed that salinity stress reduced fresh and dry weight of leaves and shoots. Also, the relative water content (RWC) of leaf and shoot decreased under salinity stress. Mean comparison showed that chlorophylls and carotenoids content were inversely associated with increasing salinity levels. The lowest levels of chlorophyll and carotenoids were observed in 12 dS m-1 treatment. Antioxidant enzymes activity such as superoxide dismutase (SOD), catalase (CAT) and guaiacolytic peroxidase (GPX) increased by increasing salt stress, although the lowest activity was observed in control treatment. Total phenol content of the leaves was also affected by increased salinity stress, but there was no significant difference between treatments. In addition, the results showed that by increasing salinity stress, the amount of soluble proteins decreased and its lowest amount was observed with 12 dS m-1 treatment. According to the results, salinity stress reduced plant growth by its effects on physiological and biochemical characteristics of Rosa damascena. Thus, it seems that the Damask Rose can tolerate a salinity level of up to 8 dS m-1, without detrimental effects on plant growth.