Study On Construction And Function Of TaNHX₂ Gene Plant Expression Vector And Plant RNAi Vector Of Na～+/H～+ Antiporter Protein Gene

The plant often suffer from adverse environmental stresses during the growth such as salinity, drought and low temperature etc. Among them, salt stress badly influences in the yields of the plant. In order to reduce harmness of salt stress, in the long run of evolution process, the plant has formed a set of endure the mechanism of salt. The plant increase the Na⁺ of outside row, or limit the Na⁺ of absorption, or Na⁺ is sequestered in vacuole. So far, we have known that some plants mainly sequester Na⁺ in vacuole in order to reduce Na⁺ harmness by the function of Na⁺/H⁺ antiport protein in vacuole. So Na⁺/H⁺ antiport protein in vacuole play an important part in protesting salt stress. With cultivated land being more and more limited, and the population continuously increasing, breeding relatively high salt resisting plant is one of targets in plant molecule breeding project.In this research, TaNHX₂ in wheat was used as experimental material, we constructed one plant expression vector, which contained TaNHX₂ gene. Using RNA interference technique to constructed one plant expression vector, which contained Na⁺/H⁺ antiport protein gene fragment. The completion of this program gets the salt resisting transgenic Arabidopsis thaliana by vacuum infiltration method. And also we have the mechanism research and physiology research backloging data for the plant anti-salt. The main test method and conclusion of this thesis are as follows:1. Using plant bivalent expression vector pBIN438 as the basic component, one plant expression vector, which contained TaNHX₂ gene. The TaNHX₂ gene was introduced into Arabidopsis thaliana and transgenic plantlets were obtained by vacuum infiltration method. The successful integration and expression of the gene was identified by PCR, Southern blot and RT-PCR. Wild type and transgenic lines were moved into MS medium. Salt and drought tolerance analysis showed that overexpression of TaNHX₂ gene in Arabidopsis thaliana could improve the growth status at 3%, 5%, 7% PEG6000 and 100mmol/L, 150mmol/L, and 200mmol/LNaCl medium compared with the wild type. The results indicated that the adverse resistance of transgenic plants was...