This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Morgan, P. W. Articles by Durham, J. I. Search for Related Content PubMed PubMed Citation Articles by Morgan, P. W. Articles by Durham, J. I. Agricola Articles by Morgan, P. W. Articles by Durham, J. I.

Articles

Abscission: Potentiating Action of Auxin Transport Inhibitors ¹

^a Department of Plant Sciences, Texas A&M University, College Station, Texas 77843

Reduction in petiolar auxin transport has been proposed as one of the functional actions of endogenous or exogenous ethylene as it regulates intact leaf abscission. If this hypothesis is correct, auxin-transport inhibitors should hasten the rate or amount of abscission achieved with a given level of ethylene. Evidence presented here indicates that the hypothesis is correct. Three auxin transport inhibitors promoted ethylene-induced intact leaf abscission when applied to specific petioles or the entire cotton plant (Gossypium hirsutum L., cv. Stoneville 213). In addition, the transport inhibitors caused rapid abscission of leaves which usually do not abscise under the conditions employed. No stimulation of abscission occurred during the initial 3 to 5 days after plants were treated with transport inhibitors unless such treatments were coupled with exogenous ethylene or that derived from 2-chloroethylphosphonic acid. However, vegetative cotton plants did abscise some of their youngest true leaves during the 2nd and 3rd weeks of exposure to transport inhibitor alone. Taken as a whole, the results indicate that reducing the auxin supply to the abscission zone materially increases sensitivity to ethylene, a condition which favors a role of endogenous ethylene in abscission regulation. Such a role of ethylene indicates the importance of auxin-ethylene interactions in the over-all hormone balance of plants and specific tissues.

This article has been cited by other articles:

				M. K. Pedersen, J. D. Burton, and H. D. Coble Effect of Cyclanilide, Ethephon, Auxin Transport Inhibitors, and Temperature on Whole Plant Defoliation Crop Sci., June 20, 2006; 46(4): 1666 - 1672. [Abstract] [Full Text] [PDF]