Ion Uptake in Relation to the Development of a Root Hypodermis

SUMMARY The suberization of the outer cortical cells in the basal zones of maize roots to form a hypodermis reduced the radial movement of phosphate towards the stele. Suberization of these cells appeared to place a far greater restriction on the translocation of phosphate to the shoot than the suberization of the endodermis. Under the same conditions as were used for growing maize, barley roots did not develop a hypodermis, and phosphate movement from the basal zones of the root axes was not restricted.