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 (26) Citing Articles via Google Scholar Google Scholar Articles by Ludwig-Müller, J. Articles by Epstein, E. Search for Related Content PubMed PubMed Citation Articles by Ludwig-Müller, J. Articles by Epstein, E. Agricola Articles by Ludwig-Müller, J. Articles by Epstein, E.

Development and Growth Regulation

Occurrence and in Vivo Biosynthesis of Indole-3-Butyric Acid in Corn (Zea mays L.) ¹

Botanisches Institut, Goethe-Universität, Siesmayerstrasse 70, 6000 Frankfurt am Main 11, Federal Republic of Germany, Agricultural Research Organization, The Volcani Center, Bet Dagan 50250, Israel

Indole-3-butyric acid (IBA) was identified as an endogenous compound in leaves and roots of maize (Zea mays L.) var Inrakorn by thin layer chromatography, high-performance liquid chromatography, and gas chromatography-mass spectrometry. Its presence was also confirmed in the variety Hazera 224. Indole-3-acetic acid (IAA) was metabolized to IBA in vivo by seedlings of the two maize varieties. The reaction product was identified by thin layer chromatography, high performance liquid chromatography, and gas chromatography-mass spectrometry after incubating the corn seedlings with [¹⁴C]IAA and [¹³C₆]IAA. The in vivo conversion of IAA to IBA and the characteristics of IBA formation in two different maize varieties of Zea mays L. (Hazera 224 and Inrakorn) were investigated. IBA-forming activity was examined in the roots, leaves, and coleoptiles of both maize varieties. Whereas in the variety Hazera 224, IBA was formed mostly in the leaves, in the variety Inrakorn, IBA synthesis was detected in the roots as well as in the leaves. A time course study of IBA formation showed that maximum activity was reached in Inrakorn after 1 hour and in Hazera after 2 hours. The pH optimum for the uptake of IAA was 6.0, and that for IBA formation was 7.0. The K_m value for IBA formation was 17 micromolar for Inrakorn and 25 micromolar for Hazera 224. The results are discussed with respect to the possible functions of IBA in the plant.

This article has been cited by other articles:

				J. J. Campanella, A. F. Olajide, V. Magnus, and J. Ludwig-Muller A Novel Auxin Conjugate Hydrolase from Wheat with Substrate Specificity for Longer Side-Chain Auxin Amide Conjugates Plant Physiology, August 1, 2004; 135(4): 2230 - 2240. [Abstract] [Full Text] [PDF]

				B. K. Zolman, A. Yoder, and B. Bartel Genetic Analysis of Indole-3-butyric Acid Responses in Arabidopsis thaliana Reveals Four Mutant Classes Genetics, November 1, 2000; 156(3): 1323 - 1337. [Abstract] [Full Text]