Preliminary Research On Salt Tolerance Improvement Of GmsSOS1 Arabidopsis Thaliana By Enhancing Antioxidant Enzyme Activities

The transgenic GmsSOS1 Arabidopsis thaliana and its wild type(WT)were used as the experimental materials in this study.Under salt and oxidative stresses,the seed germination,seeding morphology,fresh weight,leaf area,relative electrolytic leakage,MDA content,relative chlorophyll content,contents of reactive oxygen species,antioxidant enzyme activities and Na+,K+ ions content of transgenic GmsSOS1 Arabidopsis thaliana and its wild type were investigated and compared.The results showed as follows:Seed germination of transgenic GmsSOS1 Arabidopsis thaliana was increased gradually with time increasing under stress of 150 mM NaC1 and was higher than its wild type.Seedlings morphology and leaf area of transgenic GmsSOS1 Arabidopsis thaliana was stronger than the wild type.Relative electrolytic leakage of transgenic GmsSOS1 Arabidopsis thaliana was lower 3.13%than the wild type.There was significant difference in MDA content of root or shoot for transgenic GmsSOS1 Arabidopsis thaliana and the wild type.Under stress of 150 mM NaCl,O2-content of shoot of the wild type was 2.3 times that of the transgenic GmsSOS1.CAT of shoot or root of the transgenic GmsSOS1 was stronger than the wild type.APX of shoot of the transgenic GmsSOS1 was 1.97 times that of the wild type.The difference of SOD of root was up to significant for the wild type and the transgenic GmsSOS1,while without significant difference in shoot.In general,there was no significant difference in POD of root with the wild type and the transgenic GmsSOS1.It’s visible that GmsSOS1 could obviously improve the salt resistance in Arabidopsis Thaliana by antioxidant enzyme activities.Arabidopsis thaliana seedlings of GmsSOS1 and WT were all obviously inhibited with stress of 120 mM NaC1 and the ones of WT were more serious,presenting plants less,leaf chlorosis,leaf area less and salt symptom more evident than that of GmsSOS1.However,seedlings of GmsSOS1 and WT were all obviously inhibited with stress of 4mM NaCl,multiple NaC1+ MV and NaC1+H2O2,presenting leaf chlorosis,leaf area less,those more serious with that of multiple stress,especially for the WT.Leaf relative electrolytic leakage of that was lower than the WT;MDA content of root or leaf for GmsSOSl was decreased significantly as compared to WT;H2O2 content(DAB staining)of the WT were just obviously increased in comparison with the others.Na+ content of GmsSOS1 and WT were all obviously greater and K+ content of that were all obviously lower than the control when treated by NaCl,MV,H2O2 and multiple stress.However,the rising amplitude of Na+content of GmsSOS1 and the descending of K+ were all lower than the WT.This suggested that Transgenic GmsSOS1 Arabidopsis on salt resistance improved significantly for salt or oxidative stress.