| It is reviewed of new progresses of salt influx, transport and accumulation by higher plant. There are maybe three pathways for Na+ influx. Two protein-mediated pathways can be distinguished by their sensitivity to additional added Ca2+, and a third pathway appears to be due to "leakage" into the roots via the apoplast. It is clearly that initial entry of Na+ from soil solution into root is passive, and exclusion of Na+ from root is active. The xylem loading of Na+ may be active or passive. The mechanisms of Na+ removal from xylem sap are unknown. It may be through the non-selective cation channel, or K+/ Na+, Na+/H+ antiporter. Management of Na+ movement within plant requires special cell types in special locations within the plant catalyzing transport in a coordinated manner. To further understand complex, whole plant adaptation to salinity, we need to know more information about cell specific transport processes and consequences of the manipulation of transporters and signaling elements in special cell types. |