Skip Navigation


Tree Physiology Advance Access originally published online on February 13, 2009
Tree Physiology 2009 29(5):725-736; doi:10.1093/treephys/tpp009
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow All Versions of this Article:
29/5/725    most recent
tpp009v1
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 Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Google Scholar
Right arrow Articles by Behnke, K.
Right arrow Articles by Schnitzler, J.-P.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Behnke, K.
Right arrow Articles by Schnitzler, J.-P.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© The Author 2009. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oxfordjournals.org

RNAi-mediated suppression of isoprene biosynthesis in hybrid poplar impacts ozone tolerance

Katja Behnke1, Einhard Kleist2, Ricarda Uerlings2, Jürgen Wildt2, Heinz Rennenberg3 and Jörg-Peter Schnitzler1,4

1 Research Centre Karlsruhe GmbH, Institute for Meteorology and Climate Research, 82467 Garmisch-Partenkirchen, Germany
2 Research Centre Jülich GmbH, Institute of Chemistry and Dynamics of the Geosphere, ICG-3, Phytosphere, 52428 Jülich, Germany
3 Institute for Forest Botany and Tree Physiology, Albert-Ludwigs-University Freiburg, 79110 Freiburg, Germany
4 Corresponding author (joerg-peter.schnitzler{at}imk.fzk.de)


  Abstract

Isoprene is the most abundant volatile compound emitted by vegetation. It influences air chemistry and is thought to take part in plant defense reactions against abiotic stress such as high temperature or ozone. However, whether or not isoprene emission impacts ozone tolerance of plants is still in discussion. In this study, we exploited the transgenic non-isoprene emitting grey poplar (Populus x canescens (Aiton) Sm.) in a biochemical and physiological model study to investigate the effect of acute ozone stress on the elicitation of defense-related emissions of plant volatiles, on photosynthesis and on the antioxidative system. We recorded that non-isoprene emitting poplars were more resistant to ozone as indicated by less damaged leaf area and higher assimilation rates compared to ozone-exposed wild-type (WT) plants. The integral of green leaf volatile emissions was different between the two poplar phenotypes and was a reliable early marker for subsequent leaf damage. For other stress-induced volatiles, such as mono-, homo- and sesquiterpenes and methyl salicylate, similar time profiles, pattern and emission intensities were observed in both transgenic and WT plants. However, unstressed non-isoprene emitting poplars are characterized by elevated levels of ascorbate and {alpha}-tocopherol as well as by a more effective de-epoxidation ratio of xanthophylls than the WT. Since ozone quenching properties of ascorbate are much higher than those of isoprene and furthermore {alpha}-tocopherol is also an essential antioxidant, non-isoprene emitting poplars might benefit from changes within the antioxidative system by providing them with enhanced ozone tolerance.

Keywords: antioxidants, ascorbate, biogenic volatile organic compounds, green leaf volatiles, photosynthesis, {alpha}-tocopherol

Received December 18, 2008; Accepted January 22, 2009


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.