Skip Navigation



JXB Advance Access published online on January 21, 2008
Journal of Experimental Botany, doi:10.1093/jxb/erm286
This Article
Right arrow Full Text Freely available
Right arrow FREE Full Text (PDF) Freely available
Right arrow All Versions of this Article:
59/5/1081    most recent
erm286v1
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 Sprent, J. I.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Sprent, J. I.
Agricola
Right arrow Articles by Sprent, J. I.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© The Author [2008]. 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

SPECIAL ISSUE REVIEW PAPER

60Ma of legume nodulation: What's new? What's changing?

Janet I. Sprent*

Division of Applied and Environmental Biology, University of Dundee, Dundee DD1 4HN, Scotland, UK

* E-mail: jisprent{at}aol.com

Current evidence suggests that legumes evolved about 60 million years ago. Genetic material for nodulation was recruited from existing DNA, often following gene duplication. The initial process of infection probably did not involve either root hairs or infection threads. From this initial event, two branched pathways of nodule developmental processes evolved, one involving and one not involving the development of infection threads to ‘escort’ bacteria to young nodule cells. Extant legumes have a wide range of nodule structures and at least 25% of them do not have infection threads. The latter have uniform infected tissue whereas those that have infection threads have infected cells interspersed with uninfected (interstitial) cells. Each type of nodule may develop indeterminately, with an apical meristem, or show determinate growth. These nodule structures are host determined and are largely congruent with taxonomic position. In addition to variation on the plant side, the last 10 years have seen the recognition of many new types of ‘rhizobia’, bacteria that can induce nodulation and fix nitrogen. It is not yet possible to fit these into the emerging pattern of nodule evolution.

Key words: Burkholderia, Cupriavidus, legume, nitrogen fixation, nodule, rhizobia

Received 5 June 2007; Revised 22 October 2007 Accepted 23 October 2007


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.