Plant Physiol. Journal of Pharmacology and Experimental Therapeutics
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Plant Physiology 50:125-131 (1972)
© 1972 American Society of Plant Biologists

This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via CrossRef
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Apelbaum, A.
Right arrow Articles by Burg, S. P.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Apelbaum, A.
Right arrow Articles by Burg, S. P.
Agricola
Right arrow Articles by Apelbaum, A.
Right arrow Articles by Burg, S. P.
Articles

Effects of Ethylene and 2,4-Dichlorophenoxyacetic Acid on Cellular Expansion in Pisum sativum1

Akiva Apelbauma,2 and Stanley P. Burgb

a The Fairchild Tropical Garden, Miami, Florida 33156, b The Department of Biology, University of Miami, Coral Gables, Florida 33125

Ethylene inhibits growth in the subhook region of intact etiolated pea seedlings (Pisum sativum, var. Alaska) by reducing the capacity of the polar auxin transport system supplying auxin to the tissue. Application of 0.1 mM 2,4-dichlorophenoxyacetic acid reverses the growth inhibition caused by ethylene, and stimulates formation of sufficient gas to induce a swelling response in the absence of applied ethylene. Added ethylene causes a further swelling response but no change in growth rate when 0.1 mM 2,4-dichlorophenoxyacetic acid is present. If ethylene produced in response to 0.1 mM 2,4-dichlorophenoxyacetic acid is removed by hypobaric conditions, tissue swelling is prevented but the growth rate is not altered. Reducing the pressure also does not affect the growth rate of control plants. A higher concentration of 2,4-dichlorophenoxyacetic acid (1 mM) acts in a similar manner except that it also depresses growth through direct herbicidal action, whereas 0.1 mM 2,4-dichlorophenoxyacetic acid stimulates growth. Applied and auxin-induced ethylene prolong the phase of cellular expansion in both etiolated and light-grown seedlings. As long as ethylene is present, growth continues, glucose is incorporated into the cell wall, and the wall weight increases in proportion to tissue fresh weight. When ethylene is removed, glucose incorporation into the cell wall decreases and growth ceases.

2 Present address: Department of Horticulture, Michigan State University, East Lansing, Mich. 48823.

1 This work was supported by National Science Foundation Grant GB27424 to S. P. Burg.






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
ASPB Publications PLANT PHYSIOLOGY THE PLANT CELL
Copyright © 1972 by the American Society of Plant Biologists