Skip Navigation


AOBPreview originally published online on November 21, 2007
Annals of Botany 2008 101(1):153-164; doi:10.1093/aob/mcm274
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow All Versions of this Article:
101/1/153    most recent
mcm274v1
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 Related articles in Ann Bot
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 Sokoloff, D. D.
Right arrow Articles by Rudall, P. J.
PubMed
Right arrow PubMed Citation
Right arrow Articles by Sokoloff, D. D.
Right arrow Articles by Rudall, P. J.
Agricola
Right arrow Articles by Sokoloff, D. D.
Right arrow Articles by Rudall, P. J.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?


© The Author 2007. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oxfordjournals.org

Seedling Diversity in Hydatellaceae: Implications for the Evolution of Angiosperm Cotyledons

Dmitry D. Sokoloff1, Margarita V. Remizowa1, Terry D. Macfarlane2, Renee E. Tuckett3, Margaret M. Ramsay4, Anton S. Beer1, Shrirang R. Yadav5 and Paula J. Rudall4,*

1 Biological Faculty, Moscow State University, 119991 Moscow, Russia
2 Western Australian Herbarium, Science Division, Department of Environment & Conservation, Brain Street, 6258 Manjimup, WA, Australia
3 The University of Western Australia, Crawley, WA 6009 and Botanic Gardens and Parks Authority, Fraser Avenue, West Perth WA 6005 Australia
4 Royal Botanic Gardens, Kew, Richmond, Surrey TW9 3AB, UK
5 Shivaji University, Vidyanagar,Kolhapur 416 004, India

* For correspondence. E-mail p.rudall{at}kew.org

Received: 2 August 2007    Returned for revision: 30 August 2007    Accepted: 27 September 2007    Published electronically: 21 November 2007

Background and Aims: Cotyledon number has long been a primary morphological feature distinguishing monocots from other angiosperms. Recent placement of Hydatellaceae near the early-divergent angiosperm order Nymphaeales, rather than in the monocot order Poales, has prompted reassessment of seedling morphology in this poorly known family.

Methods: Seedlings of six species representing all eco-geographical groups of Hydatellaceae are described using light and scanning electron microscopy.

Key Results: Two seedling types were discovered. Material examined of Trithuria submersa, T. bibracteata, T. austinensis and T. filamentosa possess a transparent bilobed sheathing structure that surrounds the main axis below the first foliage leaf. The seed coat is attached to the sheathing structure. Seedlings of Trithuria lanterna and T. konkanensis lack a sheathing structure, and the seed coat is attached to a short, narrow lateral outgrowth on the main axis of the seedling.

Conclusions: The sheathing structure that is present in seedlings of some Hydatellaceae could be homologized with the two united cotyledons of water lilies. It also resembles the single cotyledon of some monocots, and hence demonstrates a possible pathway of the origin of a monocot-like embryo, though no homology is implied. The sheathing structure is reduced in Trithuria lanterna and T. konkanensis, and the short, narrow outgrowth of its seedling could represent a single cotyledon. This synapomorphy suggests that the only Indian species of Hydatellaceae, T. konkanensis, is closer to the northern Australian T. lanterna than to the south-western Australian T. bibracteata.

Key words: Seedling, cotyledon, monocot, dicot, Hydatellaceae, Trithuria


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

Related articles in Ann Bot:

ContentSnapshots

Ann Bot 2008 101: NP. [Extract] [Full Text]  



This article has been cited by other articles:


Home page
 ANN BOT (LOND)Home page
P. J. Rudall, M. V. Remizowa, A. S. Beer, E. Bradshaw, D. W. Stevenson, T. D. Macfarlane, R. E. Tuckett, S. R. Yadav, and D. D. Sokoloff
Comparative Ovule and Megagametophyte Development in Hydatellaceae and Water Lilies Reveal a Mosaic of Features Among the Earliest Angiosperms
Ann. Bot., May 1, 2008; 101(7): 941 - 956.
[Abstract] [Full Text] [PDF]


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.