Skip Navigation



JXB Advance Access published online on February 27, 2004
Journal of Experimental Botany, doi:10.1093/jxb/erh092
© 2004 by Oxford University Press
This Article
Right arrow FREE Full Text (PDF) Freely available
Right arrow All Versions of this Article:
55/398/919    most recent
erh092v1
Right arrow E-letters: Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when E-letters are posted
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 Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Right arrow Disclaimer
Google Scholar
Right arrow Articles by Gitz III, D. C.
Right arrow Articles by Huerta, A. J.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Gitz III, D. C.
Right arrow Articles by Huerta, A. J.
Agricola
Right arrow Articles by Gitz III, D. C.
Right arrow Articles by Huerta, A. J.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

Received September 3, 2003; accepted December 19, 2003
© 2004 Society for Experimental Biology

RESEARCH PAPER

Effects of a PAL inhibitor on phenolic accumulation and UV-B tolerance in Spirodela intermedia (Koch.)

Dennis C. Gitz III 1, Lan Liu-Gitz 2, Jerry W. McClure 3, and Alfredo J. Huerta 3*

1 Cropping Systems Research Laboratory, ARS-USDA, Lubbock, TX 79415, USA
2 Natural Resource Sciences and Landscape Architecture, University of Maryland, College Park, MD 20741, USA
3 Department of Botany; 392 Pearson Hall; Miami University, Oxford, OH 45056, USA

* To whom correspondence should be addressed. E-mail: huertaaj{at}muohio.edu.


  Abstract

Duckweed (Spirodela intermedia) was grown axenically on 1/2 strength Hutner’s nutrient solution plus 1% sucrose, with the L-phenylalanine ammonia-lyase (PAL) inhibitor 2-aminoindan-2-phosphonic acid (AIP) at 0.0, 0.05, or 10 µM, at constant 25 °C and a light intensity of 300 µmol m-2 s-1 photosynthetically active radiation from CW fluorescent lamps. Growth with 10 µM AIP led to decreased frond area and fresh weight, but dry weight was unchanged. Microscopic examination of fronds revealed increased frond thickness and a lack of reticulate aerenchyma. Ultraviolet epifluorescence microscopy and UV-Vis spectroscopy of methanolic extracts confirmed the dose-dependent inhibition of secondary phenolic synthesis with the near total elimination of secondary phenolic accumulation at the 10 µM level. AIP-treated plants showed increased sensitivity to UV-B as shown by a reduced Fv/Fm. The results provided direct evidence of the working hypothesis that phenols function to screen UV radiation from reaching photosynthetic tissues or damaging other sensitive tissues. A novel histochemical method employing zirconyl chloride to visualize phenols is discussed.

Key words: AIP, aminophosphonic acid, duckweed, flavonoid, PAL, phenolic, Spirodela, ultraviolet-B, UV.


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?




Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.