Phenotypic characterization and sampling
For the first month of salt treatment, we used a steremicroscope M165 FC (Leica, Germany) to find out whether the axillary bud was initiated by removing the leaf sheath enclosed the culm. In order to calculate the percentage of tillering, 3 plots (at least 10 seedlings) were randomly selected to determine whether the tillering was happening or not. The percentage of tillering and number of tillers per seedling were recorded every 10 days. In the same time, the plant height was measured. Each experiment was performed by three replicates. After measurement, the different tissues of S. alterniflora seedlings were cut and directly frozen in liquid nitrogen and stored in -80oC for further analysis.