Skip Navigation



JXB Advance Access published online on June 9, 2006
Journal of Experimental Botany, doi:10.1093/jxb/erj190
This Article
Right arrow FREE Full Text (PDF) Freely available
Right arrow All Versions of this Article:
57/10/2237    most recent
erj190v1
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 Tarkowski, P.
Right arrow Articles by Salopek-Sondi, B.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Tarkowski, P.
Right arrow Articles by Salopek-Sondi, B.
Agricola
Right arrow Articles by Tarkowski, P.
Right arrow Articles by Salopek-Sondi, B.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© The Author [2006]. Published by Oxford University Press [on behalf of the Society for Experimental Biology]. All rights reserved. For Permissions, please e-mail: journals.permissions@oxfordjournals.org
Received September 12, 2005
Accepted March 9, 2006

RESEARCH PAPER

Cytokinins in the perianth, carpels, and developing fruit of Helleborus niger L

Petr Tarkowski 1, Danuse Tarkowská 2, Ondrej Novák 2, Snjezana Mihaljevic 3, Volker Magnus 3, Miroslav Strnad 2, and Branka Salopek-Sondi 3 *

1 Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Umeå, Sweden; Present address: Department of Biochemistry, Faculty of Science, Palacky University, Slechtitelu 11, CZ-783 71 Olomouc, Czech Republic
2 Laboratory of Growth Regulators, Palacky University and IEB ASCR, Olomouc, Czech Republic
3 Rudjer Boskovic Institute, Zagreb, Croatia

* To whom correspondence should be addressed.
Branka Salopek-Sondi, E-mail: salopek{at}irb.hr


  Abstract

Reproductive development in the Christmas rose (Helleborus niger L.) differs from that in commonly investigated model plants in two important aspects: (i) the perianth develops a photosynthetic system, after fertilization, and persists until seed ripening; and (ii) the ripe seed contains an immature embryo which continues to mature off the mother plant. The possible roles of cytokinins in these processes are investigated here by analysing extracts of the perianth and the carpels/maturing fruit prepared during anthesis and four stages of post-floral development. trans-Zeatin, dihydrozeatin, N6-({Delta}2-isopentenyl)adenine, and their ribosides were identified by tandem mass spectrometry. Single ion monitoring in the presence of deuterated internal standards demonstrated the additional presence of the corresponding riboside-5'-monophosphates, O-glucosides, and 9-glucosides, and afforded quantitative data on the whole set of endogenous cytokinins. Fruit cytokinins were mostly localized in the seeds. Their overall concentrations increased dramatically during early seed development and remained high for 6-8 weeks, until shortly before seed ripening (the last time point covered in this work). Overall cytokinin levels in the perianth did not change markedly in the period covered, but the level of N6-({Delta}2-isopentenyl)adenine-type cytokinins appeared to increase slightly and transiently during the greening phase. The perianths of unpollinated or depistillated flowers, which survived, but did not pass through the complete greening process, contained significantly less cytokinins than observed in fruit-bearing flowers. This suggests that perianth greening requires defined cytokinin levels and supports the role of the developing fruit in their maintenance.

Keywords: Christmas rose; cytokinin identification and quantification; fruit and seed development; Helleborus niger L.; perianth greening.
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.