Improved Salt Tolerance By Transformation Of Plants With BADH And SeNHX1 Genes

High concentrations of salts in soils account for large decreases in the yield of crops all over the world. Improving the salt tolerance of plants is the most effective alternate strategy to solve this problem.Transformation of plant with salt-related genes, can enhance the plant salt tolerance while having little or no impacts on other traits. Thus, genetic engineering is of great significance for improving plant salt tolerance and understanding the mechanisms underlying it. At present, the targets of salt tolerance genetic engineering have largely been compatible solutes and Na+ compartmentation in the vacuole, and some transgenic plants with increased salt tolerance have been obtained.In this study, BADH, gene encoding the key enzyme in betaine biosynthesis, which was isolated from Atriplex hortensis, and SeNHX1, a vacuole Na+/H+ anitiporter in Salicornia europhaea L., were used to transform the tobacco to improve the salt tolerance. It is commonly known that salt tolerance is a trait controlled by multigenes. A plasmid containing SeNHX1 and BADH was constructed to study whether dual gene transformted tobacco have better salt tolerance than the single one. In addition, the genetic stability and salt tolerance in different progenies of BADH transformed tomato was also studied.The BADH transformed tomato has inherited to the T4 progeny. Southern blot results of 5 transgenic tomato lines in progenies of T0, T3 and T4, showed that the copy number of BADH had no change, except for Line T4-3 which had 3 copies in T0 progeny and one copy in the T3 and T4 progeny. The BADH enzyme activity as well as betaine content were easily detected under slat stress,which indicated that most of the transgenic lines were genetically stable. The transgenic tomato lines had higher...