Introduction Of Na～+/H～+ Transporter Gene NHX From Native Halophyte Salicornia Spp In Xinjiang Into Brassica Napus And Its Salt Tolerance

Xinjiang has the biggest poor soil area and salted region in China. 11million hectares of salted area occupy 1/3 of whole salted soil in the china and 6.6% of land area of Xinjiang. Currently there has 1/3 secondary salted soil of whole cultivation land in Xinjiang,the slight and middle degree of salted land would reduce production of 10%～50% and the heavy salted saline almost harvest nothing. This is the major cause of low yield and it also severe block of the economic development of Xinjiang.Advances in molecular genetics and plant transformation have made it feasible to utilize biotechnological strategies in improving the salt tolerance of crops,keeping steady-state growth and increasing the output in the saline environment. NHX1,a tonoplast Na+/H+ antiporter energized by the ?pH across the tonoplast,facilitates vacuolar compartmentalization of the cation. As a fundamental mechanism in salt tolerance,an active antiporter would function to sequester Na+ into the vacuole, which avoid of cytoplasmic Na+ toxicity and maintenance of a high cytoplasmic K+/Na+ ratio. In parallel, vacuolar Na+ would serve as an osmoticum necessary for cellular H2O homeostasis. Overexpressing AtNHX1 can accumulate the large numbers of antiporter in the transgenic Arabadopsis, oilseed rape and tomato, and improve their salt tolerance.Rape is widely distributed in China,America and Canada as the major oil crop. It is an important economic oil and vegetable crop,so developing transgenic varieties of rape has the potential value. So far,31% of high quality rape is...