Abstract:

The aims were to investigate the salt tolerance of Quercus aliena var. pekingensis and Quercus aliena var. acuteserrata , and compare their mechanism difference. The two-year old seedlings of Quercus aliena var. pekingensis and Quercus aliena. var. acuteserrata were studied under salt stress. The seedlings were treated with different concentrations of NaCl (1‰-4‰). The growth, physiological response of seedlings and k+, Na+ distribution were detected. The results showed that with the increment of salt concentration, the total leaf area, fresh weight and dry weight of two varieties decreased significantly, Quercus aliena var. pekingensis reduced by 30%, and Quercus aliena var. acuteserrata decreased by more than 50%, while the relative permeability of plasma membrane in leaves of two varieties increased, Quercus aliena var. acuteserrata increased by 29%, compared with Quercus aliena var. pekingensis. The SOD activity, proline and soluble protein contents of Q. acuteserrata were significantly lower than that of Q.pekingensis. More K+ were transfered from root to stem and leaf, conversely more Na+ stayed in root with two varieties. However, Q.pekingensis could maintain constant K+ content in 15 mg/g, as compared with Q.acuteserrata. Therefore, a conclusion could be drawn that both varieties were tolerant to less than 3‰ substrate salt. Salt tolerance of Q. pekingensis was better than that of Q. acuteserrata.