The influence of NaCl and Na 2SO 4 on the germination rate and cotyledon outspread rate of Populus euphratica and P. pruinosa seeds from different seed sources was studied in this paper. The results showed that the seed relative germination rate and cotyledon outspread rate were negatively correlated with salt concentration significantly. The order of salt tolerance of P. euphratica seeds and P. pruinosa seeds from different seed sources was given respectively.In the same concentration,to the germination and cotyledon outspread rate of P. euphratica from different seed sources,NaCl was more influential than Na 2SO 4.In 0～0 4% concentration,to the relative seed germination rate and cotyledon outspread rate of P. pruinosa from different seed sources,NaCl was less influential than Na 2SO 4,and in 0 4%～1 5%, NaCl was more influential than Na 2SO 4 Compared with P. pruinosa, the salt tolerance of P. euphratica in seed germination period was better.
