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Soil salinization is a very important abiotic stress factors affecting agricultural production, global resources and environmental problems and ecological issues. Salicylic acid is a common kind of phenolic compounds of plants, plants under stress conditions and accumulation of salicylic acid. Today, salicylic acid as a plant Stress response signaling molecules studied extensively. In this study, a mutant Arabidopsis wild type (Columbia), high endogenous SA accumulation snc1, salicylate transgenic plants missing nahG, salicylic acid signal transduction deletion mutant npr1-1 and sid2, ethylene synthesis blocked mutant ein2-1 ein2-1/npr1-1 double mutant of the material in the laboratory under controlled conditions of NaCl stress, through the comparative study reveals a possible mechanism of action of endogenous salicylic acid in plants in response to salt stress as well as interaction with ethylene. 6 weeks of the test plants were randomly divided into four groups, i.e. a control group and three treatment groups. The treated NaCl concentrations were set to 100 mM, 200 mM and 300 mM NaCl 5 days after the physiological and biochemical characteristics. Including: blades of superoxide dismutase (superoxide dismutase, SOD) and peroxidase (peroxidase, POD) activity, lipid peroxidation product malondialdehyde (malondialdehyde, MDA) content, the ion permeability chlorophyll content and chlorophyll a / b value, proline content. SOD, POD and CAT isoenzymes polyacrylamide gel electrophoresis analysis of the differential expression of three different concentrations of salt stress. The results showed that salt stress inhibited the growth of all the tested plants, caused different degrees off the green, and water loss, however, compared with the wild type, snc1 mutant plants are all tested plants hurt the highest level, expressed as growth retardation, old leaves turn yellow. SA low accumulation of mutant, nahG, sid2, and signal transduction missing the mutant npr1 affected by the degree of injury is relatively low, and growth by inhibition of less chlorophyll content decreased more moderate, and only showed some wilting. Compared with the respective control, salt stress increased salicylic acid mutant SOD and POD activities, especially salicylic high accumulation of mutant snc1 plants in various concentration of NaCl Stress on SOD and POD activities are the biggest and type the NaCl dose response relationship. In addition, under salt stress, salicylic acid and another plant hormone ethylene there certain interactions. Activity of SOD and POD Isozymes polyacrylamide gel electrophoresis has good consistency with the spectrophotometric solution of SOD and POD activity measured. Snc1 mutation body can be different degrees of induced antioxidant isoenzyme expression, which further suggests that the mutants are more severe oxidative stress. Under the present experimental conditions, compared with the wild-type plants, SA high accumulation of mutant snc1 MDA accumulation increased in 100 mM and 200 mM NaCl stress, low SA accumulation of mutations the body, nahG, sid2, as well as signal transduction deletion mutant npr1 MDA content in all the tested NaCl concentration stress were lower than the wild-type. Ion membrane permeability and MDA trend is consistent. These results indicate that, under salt stress, SA accumulation of high oxidative stress injury aggravated plant, while the lack of concentration of SA or signal transduction missing it will help the plants tolerance to salt stress. Proline as an important osmotica also shows differences snc1 plants tested plant salt stress response proline content in different concentrations of NaCl stress than the wild-type low, while, nahG, sid2, and proline content of npr1 higher than that of wild-type and NaCl stress causes Morphological and physiological and biochemical indices trend is consistent that Proline plays an important role in the regulation of plant tolerance to salt stress. Ethylene as a physiological function negative regulator widely involved in the regulation of plants to various abiotic stresses, usually manifested as a positive role, so ethylene deletion mutants expected not conducive to plant salt stress tolerance, and the experimental results are also available A preliminary experimental evidence. Meanwhile, some results also show that ethylene and SA have a certain interaction mechanism. In conclusion, this study shows that, under NaCl stress, endogenous SA accumulation of high oxidative stress injury to strengthen the plant, specific performance to increase the level of lipid peroxidation, such as MDA increased membrane ion permeability increase. In addition, SA high to reduce the accumulation of the chlorophyll content of the mutant osmolytes proline content decreased, while accompanied by the antioxidant enzyme activities were induced. Endogenous SA content is missing or SA signal transduction missing conducive to plant salt stress tolerance, specific performance for the vast majority of the tested indicators are better than the wild-type. Therefore, we are missing from the high accumulation of SA and SA two aspects at the same time proved the presence of SA to enhance the damage of salt stress on plants, as far as we know, there is no same coverage.
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