Response to Salt Stress of Seed Germination and System of Anti-oxidation of Grewia. biloba G. Don var. parviflora.

The seeds of G.biloba G.Don var.parviflora treated with different concentration of NaCl solution,what were observed of seed germination,the root length,wet weight of seedlings and system of anti-oxidation.The results showed that:(1)under low concentration of salt stress(50 mmol/L),its seed germination rate and the control were not significant,root length and wet weight of seedlings were higher than the control,with the salt stress strengthened,seed germination Rate,Root length and seedling fresh weight showed a downward trend.while salt stress reached 200 mmol/L,tatal rate of seed germination was only 13.8 percent.(2)under low concentration of salt stress,SOD activity was significantly higher than the control,while the salt stress reached 200 mmol/L,SOD activity started to decline;CAT activity had the same changing trend with SOD activity;POD activity increased with salt stress increasing,particularly when SOD activity declined,POD activity was still increasing.(3)with the salt stress up to the 50 mmol/L and 100 mmol/L,the content of MDA and that of the control were not significant,but when the salt stress reached 200 mmol/L,the content of MDA is 2.35 times than that of the control.