Na+ transport in plants.

The ability of plants to grow in high NaCl concentrations is associated with the ability of the plants to transport, compartmentalize, extrude, and mobilize Na(+) ions. While the influx and efflux at the roots establish the steady state rate of entry of Na(+) into the plant, the compartmentation of Na(+) into the cell vacuoles and the radial transport of Na(+) to the stele and its loading into the xylem establish the homeostatic control of Na(+) in the cytosol of the root cells. Removal of Na(+) from the transpirational stream, its distribution within the plant and its progressive accumulation in the leaf vacuoles, will determine the ability to deal with the toxic effects of Na(+). The aim of this review is to highlight and discuss the recent progress in understanding of Na(+) transport in plants.