Skip Navigation



AOBPreview published online on April 27, 2007
Annals of Botany, doi:10.1093/aob/mcm061
This Article
Right arrow Full Text Freely available
Right arrow FREE Full Text (PDF) Freely available
Right arrow Content Select
Right arrow All Versions of this Article:
99/6/1101    most recent
mcm061v1
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 Paul, L. R.
Right arrow Articles by Chanway, C. P.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Paul, L. R.
Right arrow Articles by Chanway, C. P.
Agricola
Right arrow Articles by Paul, L. R.
Right arrow Articles by Chanway, C. P.
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

Nitrogen Fixation Associated with Suillus tomentosus Tuberculate Ectomycorrhizae on Pinus contorta var. latifolia

L. R. Paul1,3,*, B. K. Chapman2 and C. P. Chanway1

1 Department of Agroecology, University of British Columbia, 2357 Main Mall, Vancouver, BC, V6T 1Z4, Canada
2 Cariboo Forest Region, Ministry of Forests, 200–640 Borland St., Williams Lake, BC, V2G 4T4, Canada
3 Department of Forest Mycology and Pathology, Swedish University of Agricultural Sciences, Box 7036, SE-750 07 Uppsala, Sweden

* For correspondence. E-mail les.paul{at}mykopat.slu.se

Received: 28 August 2006    Returned for revision: 29 October 2006    Accepted: 12 February 2007   

Background and Aims: Tuberculate ectomycorrhizae are a unique form of ectomycorrhiza where densely packed clusters of mycorrhizal root tips are enveloped by a thick hyphal sheath to form a tubercle. The functional significance of such a unique structure has not previously been established. The purpose of the present study was to investigate and measure the potential nitrogenase activity associated with Suillus tomentosus/Pinus contorta tuberculate ectomycorrhizae in two stand ages, young and old, and across a range of nitrogen-poor soil conditions.

Methods: Short roots were compared with other mycorrhizae and non-mycorrhizal secondary roots using tuberculate ectomycorrhizae. Assessment of nitrogenase activity was determined and quantitative measurements were taken on tuberculate ectomycorrhizae in situ in a variety of different circumstances, by using an adaptation of the acetylene reduction assay.

Key Results: Significant nitrogenase activity was measured associated with S. tomentosus/P. contorta tuberculate ectomycorrhizae whereas no nitrogenase activity was measured with non-tuberculate mycorrhizae or secondary roots without mycorrhizae. Average nitrogenase activity ranged from undetectable to 5696·7 nmol C2H4 g–1 tubercle 24 h–1. Maximum nitrogenase activity was 25 098·8 nmol C2H4 g–1 tubercle 24 h–1. Nitrogenase activity was significantly higher in young stands than in old stands of P. contorta. Season or some covariate also seemed to affect nitrogenase activity and there was suggestion of a site effect.

Conclusions Suillus tomentosus/P. contorta: tuberculate ectomycorrhizae are sites of significant nitrogenase activity. The nitrogenase activity measured could be an important contribution to the nitrogen budget of P. contorta stands. Season and stand age affect levels of nitrogenase activity.

Key words: Nitrogenase activity, Suillus tomentosus, tuberculate ectomycorrhizae, Pinus contorta, nitrogen budgets, acetylene reduction assay


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


This article has been cited by other articles:


Home page
 Am. J. Bot.Home page
M. E. Smith and D. H. Pfister
Tuberculate ectomycorrhizae of angiosperms: The interaction between Boletus rubropunctus (Boletaceae) and Quercus species (Fagaceae) in the United States and Mexico
Am. J. Botany, September 1, 2009; 96(9): 1665 - 1675.
[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.