Effects of Seed Soaking with Spermidine on the Germination of Tomato Seeds under NaCl Stress

The tomato cultivar 'Baiguoqiangfeng' were chose as material,tomato seed were soaked with different concentration of Spd(0,0.1,0.25,0.35,0.5 mmol/L),we studied the effect of Spd on the germination rate,germination vigor,germination index,vigor index,MDA concentration and relative electrolytic leakage of seed under 100 mmol/L NaCl stress.The results showed,in the range of low concetration,the germination rate,germination vigor,germination index and vigor index were increased,and MDA concentration and relative electrolytic leakage were decreased gradually with the rise of Spd concentration in seed soaking.However,MDA content and relative electrolytic leakage were increased,and the germination rate,germination vigor,germination index and vigor index were lower than CK when seeds were treated with too higher concent of Spd.When the concentration of Spd reached 0.25 mmol/L,the effect was best.