Investigating of growth and some antioxidant activities of Suaeda fruticosa under salinity stress and glycine betaine

Salt stress, as one of the most important factors reducing agricultural production, that increasingly threats for arid and semi-arid regions. In order to investigate the effect of glycine betaine (GB) on increasing of salinity tolerant of Suaeda fruticosa, a factorial experiment was conducted based on a completely randomized design with 3 replications during the 2017-18 growing season. The treatments were four levels of salinity stress: 3, 10, 30 and 60 dS.m and 2 levels of GB consisted of without application and spraying with 50 mM GB. The results revealed the significant effect of salinity stress and GB on all of the studied characteristics except the effect of GB on catalase. Also, the interactions effects of salinity stress and GB were significant on all of the characteristics except catalase and peroxidase. The application of GB at all levels of salinity stress increased stem length, root length, ratio of root to shoot, plant yield and leaf area than non-application of GB, so that, in shoot dry weight, the highest dry weight was observed in GB application at levels of 3 and 10 dS.m, which increased the plant dry weight by 58.48 and 47.25 percentage rather than non-application of GB, respectively. Proline, malondialdehyde, catalase and peroxidase compounds increased by increasing stress level from 3 to 60 dS.m. The production of proline, malondialdehyde and peroxidase in treated plants with GB was significantly reduced compared to non-application of GB. Generally, the results showed the positive role of GB in decreasing the effects of salinity stress on Suaeda fruticosa.