Girdling Affects Ectomycorrhizal Fungal (EMF) Diversity and Reveals Functional Differences in EMF Community Composition in a Beech Forest

Lade...
Vorschaubild
Dateien
Zu diesem Dokument gibt es keine Dateien.
Datum
2010
Autor:innen
Pena, Rodica
Offermann, Christine
Naumann, Pascale Sarah
Gessler, Arthur
Holst, Jutta
Dannenmann, Michael
Mayer, Helmut
Kögel-Knabner, Ingrid
Rennenberg, Heinz
Herausgeber:innen
Kontakt
ISSN der Zeitschrift
Electronic ISSN
ISBN
Bibliografische Daten
Verlag
Schriftenreihe
Auflagebezeichnung
URI (zitierfähiger Link)
ArXiv-ID
Internationale Patentnummer
Angaben zur Forschungsförderung
Projekt
Open Access-Veröffentlichung
Sammlungen
Core Facility der Universität Konstanz
Gesperrt bis
Titel in einer weiteren Sprache
Forschungsvorhaben
Organisationseinheiten
Zeitschriftenheft
Publikationstyp
Zeitschriftenartikel
Publikationsstatus
Published
Erschienen in
Applied and Environmental Microbiology. 2010, 76(6), pp. 1831-1841. ISSN 0099-2240. eISSN 1098-5336. Available under: doi: 10.1128/AEM.01703-09
Zusammenfassung

The relationships between plant carbon resources, soil carbon and nitrogen content, and ectomycorrhizal fungal (EMF) diversity in a monospecific, old-growth beech (Fagus sylvatica) forest were investigated by manipulating carbon flux by girdling. We hypothesized that disruption of the carbon supply would not affect diversity and EMF species numbers if EM fungi can be supplied by plant internal carbohydrate resources or would result in selective disappearance of EMF taxa because of differences in carbon demand of different fungi. Tree carbohydrate status, root demography, EMF colonization, and EMF taxon abundance were measured repeatedly during 1 year after girdling. Girdling did not affect root colonization but decreased EMF species richness of an estimated 79 to 90 taxa to about 40 taxa. Cenococcum geophilum, Lactarius blennius, and Tomentella lapida were dominant, colonizing about 70% of the root tips, and remained unaffected by girdling. Mainly cryptic EMF species disappeared. Therefore, the Shannon-Wiener index (H') decreased but evenness was unaffected. H' was positively correlated with glucose, fructose, and starch concentrations of fine roots and also with the ratio of dissolved organic carbon to dissolved organic nitrogen (DOC/DON), suggesting that both H' and DOC/DON were governed by changes in belowground carbon allocation. Our results suggest that beech maintains numerous rare EMF species by recent photosynthate. These EM fungi may constitute biological insurance for adaptation to changing environmental conditions. The preservation of taxa previously not known to colonize beech may, thus, form an important reservoir for future forest development.
In temperate and boreal forest ecosystems, most tree species form ectomycorrhizal fungal (EMF) associations. EM fungi ensheathe the root tip, forming characteristic mantlelike structures (1). The presence and lengths of hyphae emanating from the mantle are characteristic of different EMF species and establish different soil exploration types (2). It has been assumed that EMF communities are adapted specifically to mobilize sparse soil nutrient resources in boreal and temperate forests (11, 50). Current estimates indicate that about 80% of all nitrogen and phosphorus present in plants has been taken up via mycorrhizas (30, 41, 63).
Unlike free-living soil microbes, EM fungi have direct access to reduced carbon from their host plants. More than 50 years ago, Melin and Nilsson (46) showed that 14C applied to leaves was recovered within one day in EM fungi, suggesting a strong dependence of fungal metabolism on host photosynthesis. Subsequent isotopic studies corroborated tight connections between current photosynthate and EM fungi (28, 42). EMF hyphae constitute the main path of plant-derived carbon into the soil (24, 29). Furthermore, EMF hyphae contribute substantially to soil respiration (25% from hyphae and 15% from roots) (27). As hyphal respiration decreases strongly in response to girdling of trees, a tight metabolic link between extramatrical mycelia and host photosynthetic activity must exist (5, 9, 32). In addition, fruiting body formation of EMF species was strongly dependent on host photosynthetic capacity (32, 40). In contrast, the significance of the current assimilate supply for EMF colonization of root tips and for community composition is not yet well understood. Since trees contain substantial stores of carbohydrates in the roots and stem (7), it may be expected that EM fungi can be maintained if this carbon resource is available. For example, defoliation experiments with conifers, which restricted but did not eliminate current photosynthate transfer to roots, showed no effects on root EMF colonization. Massive defoliation that negatively affected aboveground biomass production suppressed morphotypes with thick mantles compared to those with thin mantles, suggesting a shift to less-carbon-demanding EMF species (14, 40, 44, 54, 56). Earlier studies also reported decreased EMF colonization of root tips (21, 52).
In a common garden experiment with young beech trees, strong shading over several years, which severely limited plant growth, suppressed EMF colonization and resulted in low EMF diversity (20). EMF community composition was affected strongly by shading and slightly by short-term girdling, suggesting that EMF taxa are sensitive to changes in plant internal carbohydrate resources (20). However, the overall EMF diversity was low, probably because the young trees were grown in nutrient-rich compost soil (20). The significance of photoassimilates for EMF abundance, diversity, and community composition, therefore, remains to be shown for adult forest trees, which usually have high EMF diversity and low nitrogen availability (10, 26, 53, 61).
The aim of this work was to test the hypothesis that EMF abundance and diversity are independent of the current photoassimilate supply and can be maintained by internal resources. To investigate this concept, old-growth beech trees (Fagus sylvatica L.) were girdled to suppress carbon allocation to roots. Since disruption of the current assimilate flux affects the carbohydrate source strength, we hypothesized that changes in EMF taxon composition would occur if EMF species had different carbon demands. Tree carbohydrate status, root demography, EMF colonization, and EMF taxon abundance were measured repeatedly during 1 year after girdling. Since girdling also affects carbon release into and probably nutrient uptake from soil, the influence of possible feedback by changes in the ratio of dissolved organic carbon to dissolved organic nitrogen (DOC/DON) in the soil on EMF diversity was also assessed.

Zusammenfassung in einer weiteren Sprache
Fachgebiet (DDC)
570 Biowissenschaften, Biologie
Schlagwörter
Konferenz
Rezension
undefined / . - undefined, undefined
Zitieren
ISO 690PENA, Rodica, Christine OFFERMANN, Judy SIMON, Pascale Sarah NAUMANN, Arthur GESSLER, Jutta HOLST, Michael DANNENMANN, Helmut MAYER, Ingrid KÖGEL-KNABNER, Heinz RENNENBERG, Andrea POLLE, 2010. Girdling Affects Ectomycorrhizal Fungal (EMF) Diversity and Reveals Functional Differences in EMF Community Composition in a Beech Forest. In: Applied and Environmental Microbiology. 2010, 76(6), pp. 1831-1841. ISSN 0099-2240. eISSN 1098-5336. Available under: doi: 10.1128/AEM.01703-09
BibTex
@article{Pena2010-03Girdl-43303,
  year={2010},
  doi={10.1128/AEM.01703-09},
  title={Girdling Affects Ectomycorrhizal Fungal (EMF) Diversity and Reveals Functional Differences in EMF Community Composition in a Beech Forest},
  number={6},
  volume={76},
  issn={0099-2240},
  journal={Applied and Environmental Microbiology},
  pages={1831--1841},
  author={Pena, Rodica and Offermann, Christine and Simon, Judy and Naumann, Pascale Sarah and Gessler, Arthur and Holst, Jutta and Dannenmann, Michael and Mayer, Helmut and Kögel-Knabner, Ingrid and Rennenberg, Heinz and Polle, Andrea}
}
RDF
<rdf:RDF
    xmlns:dcterms="http://purl.org/dc/terms/"
    xmlns:dc="http://purl.org/dc/elements/1.1/"
    xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
    xmlns:bibo="http://purl.org/ontology/bibo/"
    xmlns:dspace="http://digital-repositories.org/ontologies/dspace/0.1.0#"
    xmlns:foaf="http://xmlns.com/foaf/0.1/"
    xmlns:void="http://rdfs.org/ns/void#"
    xmlns:xsd="http://www.w3.org/2001/XMLSchema#" > 
  <rdf:Description rdf:about="https://kops.uni-konstanz.de/server/rdf/resource/123456789/43303">
    <dc:contributor>Pena, Rodica</dc:contributor>
    <dc:creator>Simon, Judy</dc:creator>
    <dc:creator>Naumann, Pascale Sarah</dc:creator>
    <void:sparqlEndpoint rdf:resource="http://localhost/fuseki/dspace/sparql"/>
    <dc:creator>Pena, Rodica</dc:creator>
    <dc:creator>Holst, Jutta</dc:creator>
    <dc:contributor>Kögel-Knabner, Ingrid</dc:contributor>
    <dc:creator>Kögel-Knabner, Ingrid</dc:creator>
    <dc:contributor>Mayer, Helmut</dc:contributor>
    <dc:creator>Gessler, Arthur</dc:creator>
    <dc:creator>Dannenmann, Michael</dc:creator>
    <dc:contributor>Dannenmann, Michael</dc:contributor>
    <foaf:homepage rdf:resource="http://localhost:8080/"/>
    <dc:creator>Polle, Andrea</dc:creator>
    <dspace:isPartOfCollection rdf:resource="https://kops.uni-konstanz.de/server/rdf/resource/123456789/28"/>
    <dc:creator>Mayer, Helmut</dc:creator>
    <dcterms:issued>2010-03</dcterms:issued>
    <dc:contributor>Simon, Judy</dc:contributor>
    <dcterms:available rdf:datatype="http://www.w3.org/2001/XMLSchema#dateTime">2018-09-18T11:51:07Z</dcterms:available>
    <dc:creator>Rennenberg, Heinz</dc:creator>
    <dc:date rdf:datatype="http://www.w3.org/2001/XMLSchema#dateTime">2018-09-18T11:51:07Z</dc:date>
    <dcterms:abstract xml:lang="eng">The relationships between plant carbon resources, soil carbon and nitrogen content, and ectomycorrhizal fungal (EMF) diversity in a monospecific, old-growth beech (Fagus sylvatica) forest were investigated by manipulating carbon flux by girdling. We hypothesized that disruption of the carbon supply would not affect diversity and EMF species numbers if EM fungi can be supplied by plant internal carbohydrate resources or would result in selective disappearance of EMF taxa because of differences in carbon demand of different fungi. Tree carbohydrate status, root demography, EMF colonization, and EMF taxon abundance were measured repeatedly during 1 year after girdling. Girdling did not affect root colonization but decreased EMF species richness of an estimated 79 to 90 taxa to about 40 taxa. Cenococcum geophilum, Lactarius blennius, and Tomentella lapida were dominant, colonizing about 70% of the root tips, and remained unaffected by girdling. Mainly cryptic EMF species disappeared. Therefore, the Shannon-Wiener index (H') decreased but evenness was unaffected. H' was positively correlated with glucose, fructose, and starch concentrations of fine roots and also with the ratio of dissolved organic carbon to dissolved organic nitrogen (DOC/DON), suggesting that both H' and DOC/DON were governed by changes in belowground carbon allocation. Our results suggest that beech maintains numerous rare EMF species by recent photosynthate. These EM fungi may constitute biological insurance for adaptation to changing environmental conditions. The preservation of taxa previously not known to colonize beech may, thus, form an important reservoir for future forest development.&lt;br /&gt;In temperate and boreal forest ecosystems, most tree species form ectomycorrhizal fungal (EMF) associations. EM fungi ensheathe the root tip, forming characteristic mantlelike structures (1). The presence and lengths of hyphae emanating from the mantle are characteristic of different EMF species and establish different soil exploration types (2). It has been assumed that EMF communities are adapted specifically to mobilize sparse soil nutrient resources in boreal and temperate forests (11, 50). Current estimates indicate that about 80% of all nitrogen and phosphorus present in plants has been taken up via mycorrhizas (30, 41, 63).&lt;br /&gt;Unlike free-living soil microbes, EM fungi have direct access to reduced carbon from their host plants. More than 50 years ago, Melin and Nilsson (46) showed that &lt;sup&gt;14&lt;/sup&gt;C applied to leaves was recovered within one day in EM fungi, suggesting a strong dependence of fungal metabolism on host photosynthesis. Subsequent isotopic studies corroborated tight connections between current photosynthate and EM fungi (28, 42). EMF hyphae constitute the main path of plant-derived carbon into the soil (24, 29). Furthermore, EMF hyphae contribute substantially to soil respiration (25% from hyphae and 15% from roots) (27). As hyphal respiration decreases strongly in response to girdling of trees, a tight metabolic link between extramatrical mycelia and host photosynthetic activity must exist (5, 9, 32). In addition, fruiting body formation of EMF species was strongly dependent on host photosynthetic capacity (32, 40). In contrast, the significance of the current assimilate supply for EMF colonization of root tips and for community composition is not yet well understood. Since trees contain substantial stores of carbohydrates in the roots and stem (7), it may be expected that EM fungi can be maintained if this carbon resource is available. For example, defoliation experiments with conifers, which restricted but did not eliminate current photosynthate transfer to roots, showed no effects on root EMF colonization. Massive defoliation that negatively affected aboveground biomass production suppressed morphotypes with thick mantles compared to those with thin mantles, suggesting a shift to less-carbon-demanding EMF species (14, 40, 44, 54, 56). Earlier studies also reported decreased EMF colonization of root tips (21, 52).&lt;br /&gt;In a common garden experiment with young beech trees, strong shading over several years, which severely limited plant growth, suppressed EMF colonization and resulted in low EMF diversity (20). EMF community composition was affected strongly by shading and slightly by short-term girdling, suggesting that EMF taxa are sensitive to changes in plant internal carbohydrate resources (20). However, the overall EMF diversity was low, probably because the young trees were grown in nutrient-rich compost soil (20). The significance of photoassimilates for EMF abundance, diversity, and community composition, therefore, remains to be shown for adult forest trees, which usually have high EMF diversity and low nitrogen availability (10, 26, 53, 61).&lt;br /&gt;The aim of this work was to test the hypothesis that EMF abundance and diversity are independent of the current photoassimilate supply and can be maintained by internal resources. To investigate this concept, old-growth beech trees (Fagus sylvatica L.) were girdled to suppress carbon allocation to roots. Since disruption of the current assimilate flux affects the carbohydrate source strength, we hypothesized that changes in EMF taxon composition would occur if EMF species had different carbon demands. Tree carbohydrate status, root demography, EMF colonization, and EMF taxon abundance were measured repeatedly during 1 year after girdling. Since girdling also affects carbon release into and probably nutrient uptake from soil, the influence of possible feedback by changes in the ratio of dissolved organic carbon to dissolved organic nitrogen (DOC/DON) in the soil on EMF diversity was also assessed.</dcterms:abstract>
    <bibo:uri rdf:resource="https://kops.uni-konstanz.de/handle/123456789/43303"/>
    <dc:contributor>Rennenberg, Heinz</dc:contributor>
    <dcterms:title>Girdling Affects Ectomycorrhizal Fungal (EMF) Diversity and Reveals Functional Differences in EMF Community Composition in a Beech Forest</dcterms:title>
    <dcterms:isPartOf rdf:resource="https://kops.uni-konstanz.de/server/rdf/resource/123456789/28"/>
    <dc:language>eng</dc:language>
    <dc:creator>Offermann, Christine</dc:creator>
    <dc:contributor>Naumann, Pascale Sarah</dc:contributor>
    <dc:contributor>Polle, Andrea</dc:contributor>
    <dc:contributor>Offermann, Christine</dc:contributor>
    <dc:contributor>Gessler, Arthur</dc:contributor>
    <dc:contributor>Holst, Jutta</dc:contributor>
  </rdf:Description>
</rdf:RDF>
Interner Vermerk
xmlui.Submission.submit.DescribeStep.inputForms.label.kops_note_fromSubmitter
Kontakt
URL der Originalveröffentl.
Prüfdatum der URL
Prüfungsdatum der Dissertation
Finanzierungsart
Kommentar zur Publikation
Allianzlizenz
Corresponding Authors der Uni Konstanz vorhanden
Internationale Co-Autor:innen
Universitätsbibliographie
Nein
Begutachtet
Ja
Diese Publikation teilen