The Adaptation of Suaeda physophora Seedlings to Salinity and Drought Environments

We investigated the effect of combined salinity and drought stress on ion accumulation, membrane permeability in leaves, and seedling survival and shoot dry weight of Suaeda physophora seedlings after they were rewatered. The results showed that drought stress increased leaf Na+ and Cl- content, especially at 400mmol.L-1 NaCl pretreatment, while drought treatment had no effect on leaf K+ content after seedlings were pretreated with either 1 or 400mmol.L-1 NaCl. Shoot dry weight of seedlings decreased during drought treatment compared to control (without drought treatment) regardless the concentrations of salinity after seedlings were rewatered. Drought treatment had less adverse effect on the seedling and leaf survival in seedlings pretreated at 400mmol.L-1 NaCl than at 1 mmol.L-1 NaCl after seedlings were rewatered. The present results indicate that seedlings of S. physophora pretreated with salinity can increase seedling survival, and this can help them to adapt to combined salinity and drought stress in arid areas.