ISSN:
1399-3054
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Biology
Notes:
Lanolin containing 3H-IAA was applied to apical cut ends of stem segments and decapitated plants of Cordyline terminalis, a monocotyledon possessing true secondary growth. Distribution of extracted label showed that: 1) in horizontal stems up to 7 times as much label accumulates in the lower surface compared to the upper surface, and this ratio increases with distance from the cut apical surface; 2) in upright stems most label (62%) occurs in the cambial and cortical regions, external to the primary and secondary vascular tissues; and 3) in upright stems having the cambium and cortical regions removed by a girdle, label accumulates above the girdle (c. 10 times greater than the control). These data are in accord with a theory of branch dimorphism derived from morphological studies, which suggested that high auxin levels initiate and maintain rhizomes and low levels initiate leafy shoots.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1399-3054.1974.tb03707.x
