Abstract: The review summarizes variations in ATPase activity under NaCl stress conditions and the possible regulation mechanisms in higher plants. Vacuolar H+_ATPase showed higher correlation with plant salinity tolerance because of its contribution to salt ion compartmentation. In general, V-H+_ATPase activity is increased in salt-tolerant plant species, which presumably results from the increased genetic expression and synthesis of tonoplast H+_ATPase subunits under saline conditions. Salinity results in a decreased activity of plasma membrane H+_ATPase, which is the result of reduced H+_ATPase synthesis. However, the effects of salt stress on plasma membrane H+_ATPase activity depend on the intensity and duration of salt stress. In addition, the effect of salt stress-induced signal transduction on ATPase control and relevance to salinity tolerance is elucidated. Collectively, understanding ATPase responses to NaCl stress is favorable for elucidating plant adaptation mechanisms and subsequent plant breeding.

Key words: Salt stress, Vacuolar H+_ATPase, Plasma membrane H+_ATPase, Ca2+-ATPase, Salt tolerance