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 CrossRef Citing Articles via Web of Science (11) Citing Articles via Google Scholar Google Scholar Articles by Black, R. C. Articles by Hamilton, R. H. Search for Related Content PubMed PubMed Citation Articles by Black, R. C. Articles by Hamilton, R. H. Agricola Articles by Black, R. C. Articles by Hamilton, R. H.

Articles

Indoleacetic Acid Synthesis in Soybean Cotyledon Callus Tissue ¹

^a Department of Biology, The Pennsylvania State University, Media, Pennsylvania 19063, University Park, Pennsylvania 16802

Growth of an auxin-requiring soybean cotyledon callus tissue (Glycine max L., Merr. var. Acme) was promoted by tryptophan, tryptamine, indole, indoleacetamide and, to a very slight degree, anthranilic acid. When tryptophan-3-¹⁴C was supplied in the growth medium, labeled indoleacetic acid (IAA) was found in both the tissue and the medium. Medium, from which the cells had been removed, was also found to convert labeled tryptophan to IAA. Soybean callus contained 0.044 µmole/g free tryptophan, but this is apparently not available for conversion to IAA. These results suggest that while exogenously supplied trytophan could elevate a specific internal pool where IAA synthesis occurs some of the growth on a tryptophan medium can be accounted for by external conversion.