Please use this identifier to cite or link to this item: http://hdl.handle.net/1942/2467
Title: Nitrogen availability and colonization by mycorrhizal fungi correlate with nitrogen isotope patterns in plants
Authors: Hobbie, EA
COLPAERT, Jan 
Issue Date: 2003
Publisher: BLACKWELL PUBLISHING LTD
Source: NEW PHYTOLOGIST, 157(1). p. 115-126
Abstract: Nitrogen isotope (delta(15)N) patterns in plants may provide insight into plant N dynamics. Here, two analytical models of N-isotope cycling in plants and mycorrhizal fungi were tested, as dominant plants in many forest ecosystems obtain most of their N through intereactions with mycorrhizal fungi. Fungi were treated either as a single well-mixed N pool, or as two N pools (one available, plus one not available, for transfer to the host). Models were compared against complete biomass and (15) N budgets from culture studies of nonmycorrhizal and ectomycorrhizal Pinus sylvestris (colonized with Suillus luteus or Thelephora terrestris) grown exponentially at low and high N supply. Fungal biomass and N increased at low N relative to high N supply, whereas needle delta(15) N decreased. Needle delta(15)N correlated strongly and negatively with biomass of extraradical hyphae. Our data and models suggest that low plant delta(15) N values in low productivity and N-limited environments result partly from high retention of (15) N-enriched N by mycorrhizal fungi; this retention was driven by increased C flux to fungi under N-limited conditions. The two-pool model of fungal N accounted for greater variability in plant delta N-15 than the one-pool model. Plant delta (15) N patterns may indicate relative allocation of fixed C from plants to mycorrhizal fungi under some conditions. Studies are needed on whether patterns observed in culture can be applied to interpret field measurements of delta(15) N.
Notes: Max Planck Inst Biogeochem, D-07701 Jena, Germany. Limburgs Univ Ctr, B-3590 Diepenbeek, Belgium.Hobbie, EA, Univ New Hampshire, Complex Syst Res Ctr, Morse Hall, Durham, NH 03824 USA.
Keywords: nitrogen isotope (delta N-15) patterns; Pinus sylvestris; mycorrhizal fungi; N cycling; C flux; biomass
Document URI: http://hdl.handle.net/1942/2467
ISSN: 0028-646X
e-ISSN: 1469-8137
DOI: 10.1046/j.1469-8137.2003.00657.x
ISI #: 000179945400013
Category: A1
Type: Journal Contribution
Validations: ecoom 2004
Appears in Collections:Research publications

Show full item record

SCOPUSTM   
Citations

159
checked on Sep 3, 2020

WEB OF SCIENCETM
Citations

186
checked on May 21, 2022

Page view(s)

60
checked on May 27, 2022

Google ScholarTM

Check

Altmetric


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.