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 Web of Science 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 Web of Science (31) Citing Articles via Google Scholar Google Scholar Articles by Evans, M. L. Search for Related Content PubMed PubMed Citation Articles by Evans, M. L. Agricola Articles by Evans, M. L.

Articles

A New Sensitive Root Auxanometer

Preliminary Studies of the Interaction of Auxin and Acid pH in the Regulation of Intact Root Elongation ¹

^a Department of Botany, The Ohio State University, Columbus, Ohio 43210

A new sensitive root auxanometer is described. The auxanometer represents an adaption of the position-sensor transducer method to measurement of intact root elongation and has the advantages of simplicity and high sensitivity. Experiments with the auxanometer show that auxin begins to inhibit intact pea root elongation within 10 minutes and continues to inhibit elongation for at least 1 hour following a 1-hour treatment with the hormone. Exposure of pea roots to pH 4 results in a 2- to 3-fold increase in elongation rate beginning about 1 minute after acid treatment. Acid-induced elongation continues at a steady rate for at least 160 minutes and can be reinitiated repeatedly by shifting between pH 4 and 6.5. Auxin inhibits acid-induced elongation whether given before or after acidification, and a transient exposure to auxin renders intact roots relatively insensitive to acid for at least 1 hour after withdrawal of the hormone.

This article has been cited by other articles:

				A. J. BLOOM, J. FRENSCH, and A. R. TAYLOR Influence of Inorganic Nitrogen and pH on the Elongation of Maize Seminal Roots Ann. Bot., May 1, 2006; 97(5): 867 - 873. [Abstract] [Full Text] [PDF]

				A. Liszkay, E. van der Zalm, and P. Schopfer Production of Reactive Oxygen Intermediates (O2{middle dot}-, H2O2, and {middle dot}OH) by Maize Roots and Their Role in Wall Loosening and Elongation Growth Plant Physiology, October 1, 2004; 136(2): 3114 - 3123. [Abstract] [Full Text] [PDF]

				J. M. Fasano, S. J. Swanson, E. B. Blancaflor, P. E. Dowd, T.-h. Kao, and S. Gilroy Changes in Root Cap pH Are Required for the Gravity Response of the Arabidopsis Root PLANT CELL, April 1, 2001; 13(4): 907 - 922. [Abstract] [Full Text]

				G. T.S. Beemster and T. I. Baskin STUNTED PLANT 1 Mediates Effects of Cytokinin, But Not of Auxin, on Cell Division and Expansion in the Root of Arabidopsis Plant Physiology, December 1, 2000; 124(4): 1718 - 1727. [Abstract] [Full Text]

				W. S. Peters and H. H. Felle The Correlation of Profiles of Surface pH and Elongation Growth in Maize Roots Plant Physiology, November 1, 1999; 121(3): 905 - 912. [Abstract] [Full Text]