title: Carbon and nitrogen fluxes between beech and their ectomycorrhizal assemblage.
abstract: To determine the exchange of nitrogen and carbon between ectomycorrhiza and host plant, young beech (Fagus sylvatica) trees from natural regeneration in intact soil cores were labelled for one growing season in a greenhouse with (13)CO2 and (15)NO3 (15)NH4. The specific enrichments of (15)N and (13)C were higher in ectomycorrhizas (EMs) than in any other tissue. The enrichments of (13)C and (15)N were also higher in the fine-root segments directly connected with the EM (mainly second-order roots) than that in bulk fine or coarse roots. A strict, positive correlation was found between the specific (15)N enrichment in EM and the attached second-order roots. This finding indicates that strong N accumulators provide more N to their host than low N accumulators. A significant correlation was also found for the specific (13)C enrichment in EM and the attached second-order roots. However, the specific enrichments for (15)N and (13)C in EM were unrelated showing that under long-term conditions, C and N exchange between host and EMs are uncoupled. These findings suggest that EM-mediated N flux to the plant is not the main control on carbon flux to the fungus, probably because EMs provide many different services to their hosts in addition to N provision in their natural assemblages.
authors.affiliation: Büsgen Institute, Forest Botany and Tree Physiology, Georg August University Göttingen, Büsgenweg 2, 37077, Göttingen, Germany.
authors.forename: Kerttu
authors.initials: K
authors.lastname: Valtanen
authors.forename: Verena
authors.initials: V
authors.lastname: Eissfeller
authors.forename: Friderike
authors.initials: F
authors.lastname: Beyer
authors.forename: Dietrich
authors.initials: D
authors.lastname: Hertel
authors.forename: Stefan
authors.initials: S
authors.lastname: Scheu
authors.forename: Andrea
authors.initials: A
authors.lastname: Polle
mesh_terms: D002244:Carbon / Q000378:metabolism*; D029964:Fagus / Q000378:metabolism* / Q000382:microbiology*; D038821:Mycorrhizae / Q000378:metabolism*; D009584:Nitrogen / Q000378:metabolism*; D013559:Symbiosis
chemical_list: D002244:Carbon; D009584:Nitrogen
references.citation: New Phytol. 2012 Oct;196(2):367-382
references.pmid: 22963677
references.citation: Mycorrhiza. 2008 Oct;18(8):413-427
references.pmid: 18719949
references.citation: ISME J. 2014 Feb;8(2):321-30
references.pmid: 24030593
references.citation: Oecologia. 2000 Jun;123(4):550-559
references.pmid: 28308764
references.citation: Ecol Lett. 2009 Jan;12(1):13-21
references.pmid: 19019195
references.citation: FEMS Microbiol Ecol. 2002 Feb 1;39(2):147-56
references.pmid: 19709194
references.citation: Mycorrhiza. 2011 May;21(4):297-308
references.pmid: 20886243
references.citation: Plant Cell Environ. 2009 Aug;32(8):992-1003
references.pmid: 19344334
references.citation: Appl Environ Microbiol. 2010 Mar;76(6):1831-41
references.pmid: 20097809
references.citation: New Phytol. 2013 Jul;199(2):520-528
references.pmid: 23594339
references.citation: New Phytol. 2008;177(1):220-228
references.pmid: 17944822
references.citation: New Phytol. 2010 Jul;187(2):485-493
references.pmid: 20456043
references.citation: Oecologia. 2013 Dec;173(4):1439-50
references.pmid: 23912260
references.citation: Proc Natl Acad Sci U S A. 2012 Feb 14;109(7):2666-71
references.pmid: 22308426
references.citation: New Phytol. 2013 Apr;198(1):214-221
references.pmid: 23356503
references.citation: Mycorrhiza. 2011 Jan;21(1):35-51
references.pmid: 20393757
references.citation: Ecology. 2006 Apr;87(4):892-902
references.pmid: 16676533
references.citation: FEMS Microbiol Ecol. 2004 Jan 1;47(1):31-7
references.pmid: 19712344
references.citation: Tree Physiol. 2011 May;31(5):531-8
references.pmid: 21636693
references.citation: Tree Physiol. 2012 Jun;32(6):776-98
references.pmid: 22700544
references.citation: New Phytol. 2005 Jun;166(3):1063-8
references.pmid: 15869663
references.citation: Science. 2011 Aug 12;333(6044):880-2
references.pmid: 21836016