Journal
ANNALS OF BOTANY
Volume 91, Issue 4, Pages 465-471Publisher
OXFORD UNIV PRESS
DOI: 10.1093/aob/mcg043
Keywords
auxin; bioassay; 2,4-D; epinasty; IAA; inhibition; leaf curvature; Nicotiana tabacum; tobacco
Categories
Ask authors/readers for more resources
It has been reported that auxin induces an epinastic growth response in plant leaf tissues. Leaf strips of tobacco (Nicotiana tabacum L. 'Bright Yellow 2') were used to study the effects of indole-3-acetic acid (IAA), the principal form of auxin in higher plants, and a synthetic auxin, 2,4-dichlorophenoxyacetic acid (2,4-D), on epinastic, leaf curvature. Incubation of leaf strips with 10 mu m LAA resulted in a marked epinastic, curvature response. Unexpectedly, 2,4-D showed only a weak IAA-like activity in inducing epinasty. Interestingly, the presence of 2,4-D resulted in inhibition of the IAA-dependent epinastic curvature. In vivo Lineweaver-Burk kinetic analysis clearly indicated that the interaction between IAA and 2,4-D reported here is not a result of competitive inhibition. Using kinetic analysis, it was not possible to determine whether the mode of interaction between IAA and 2,4-D was non-competitive or uncompetitive. 2,4-D inhibits the IAA-dependent epinasty via complex and as yet unidentified mechanisms. (c) 2003 Annals of Botany Company.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available