Abstract
The effect of ethylene on the distribution of applied indoleacetic acid in the petiole of Coleus blumei Benth. X C. frederici G. Taylor has been investigated during the development of epinastic curvature. Using intact plants, 14C-IAA was applied to the distal region of the leaf lamina and the accumulation of label in the abaxial and adaxial halves of 5 mm petiole sections was determined after 1.5, 3, and 6 hours. Over this period the label was transported out of the lamina into the petiole at a rate of at least 66 mm hr−1. Of the total amount of label in the petiole sections, 24 to 30% was located in the adaxial half and this distribution was not altered significantly by exposing plants to an atmosphere containing 50 μl/l ethylene. Thus when epinastic curvature is induced by ethylene there is no associated increase in the IAA content of the expanding adaxial half. The role of endogenous IAA in petiole epinasty was studied by restricting its movement with DPX 1840 (3,3a-dihydro-2-[p-methoxyphenyl]-8H-pyrozolo{5,1-a}isoindol-8-one). The leaf petioles still showed an initial epinastic response to ethylene. It is concluded that ethylene-induced epinasty is not dependent upon either any change in the transport of IAA or its redistribution within the petiole.
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- Beyer E. M. Auxin transport: a new synthetic inhibitor. Plant Physiol. 1972 Sep;50(3):322–327. doi: 10.1104/pp.50.3.322. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Leather G. R., Forrence L. E. Increased Ethylene Production during Clinostat Experiments May Cause Leaf Epinasty. Plant Physiol. 1972 Feb;49(2):183–186. doi: 10.1104/pp.49.2.183. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lyon C. J. Ethylene inhibition of auxin transport by gravity in leaves. Plant Physiol. 1970 May;45(5):644–646. doi: 10.1104/pp.45.5.644. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Morgan P. W., Gausman H. W. Effects of ethylene on auxin transport. Plant Physiol. 1966 Jan;41(1):45–52. doi: 10.1104/pp.41.1.45. [DOI] [PMC free article] [PubMed] [Google Scholar]