The protoplast intrinsic proteins (PIPs) form a large part of Aquaporin family of ancient origin and are found in bacteria,fungi,animals,and plants.PIPs act as channels in membranes to facilitate passive transport of water and some other substrates like CO2,glycerol or urea across the cell membrane.However,the majority of PIPs are characterized in rice and Arabidopsis,very few wheat members of the PIP family have been known and many more have to be identified.