Radioautographic and chemical studies of incorporation into sycamore vascular tissue walls.

There have been several recent electron-microscopic studies on the development of the vascular cambium (Bouck & Cronshaw, 1965; Buvat, 1963, 1964; Cronshaw, 1967; Esau & Cheadle, 1965; Srivastava & O'Brien, 1966; Northcote & Wooding, 1966; Wooding & Northcote, 1964; Wooding, 1966). The organelles involved have been tentatively identified and functions for each suggested. The present report is of a study using electron-microscope radioautography in parallel with a chemical analysis of sycamore vascular tissue, in order to define the functions of the organellar systems involved more closely. Tritiated glucose and phenylalanine were fed to allow a comparison of wall development including lignification.