Isolation and Activity Analysis of Different Length ThVHAc1 Promoters Cloning and Expression Analysis of a Plasma Membrane Na+/H+ Antiporter Gene in Tamarix hispida Reactive Oxygen Metabolism of the TheIF1A Transgenic Tobacco under Methyl Viologen Stress The Expression of VATPase Subunits in Overexpression ThVHAc1 Arabidopsis under Salt Stress