Further Evidence of Polar Movement of Nutrients in Plants

Abstract

IN two earlier papers I showed that there was good evidence for postulating polar rather than transverse movement of materials in plants^1a,b. This conclusion was supported by later work on the movement of fluorescein in the xylem system^1c, of labelled carbon² and of labelled phosphorus³. The two last papers describe experiments which show that carbon-14 or phosphorus-32 when introduced on one side into the leaves or the roots respectively of plants pass freely and rapidly up to the tissues on that side, but do not move transversely across the plant.