oru.sePublikationer
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Quantitative analysis of exudates from soil-living basidiomycetes in pure culture as a response to lead, cadmium and arsenic stress
Örebro University, School of Science and Technology. (MTM)
Department of Forest Mycology and Pathology, Swedish University of Agricultural Sciences.
Department of Forest Mycology and Pathology, Swedish University of Agricultural Sciences.
Örebro University, School of Science and Technology. (MTM)
2008 (English)In: Soil Biology and Biochemistry, ISSN 0038-0717, E-ISSN 1879-3428, Vol. 40, no 9, 2225-2236 p.Article in journal (Refereed) Published
Abstract [en]

Six different ectomycorrhizal fungi (Hebeloma velutipes, Piloderma byssinum, Paxillus involutus, Rhizopogonroseolus, Suillus bovinus and Suillus variegatus) and two saprotrophic fungi (Hypholoma fasciculare andHypholoma capnoides) were exposed to metal stress induced by Pb, Cd and As. After pre-growth ina nutrient solution in Petri dishes, metal exposure was performed either in a nutrient rich solution or ina nutrient poor solution for seven days. The fungi were exposed to two different metal concentrations,low and high (Pb: 10 þ 100 mM; Cd: 1 þ 10 mM; As: 1 þ 10 mM). Exudation of low molecular weightorganic compounds (low molecular weight organic acids (LMWOA), amino acids and dissolved monosaccharides),as well as dissolved organic carbon was quantified as a potential response to the metalstress. The main LMWOA identified was oxalate. Oxalate exudation increased significantly in response toboth low and high Pb and Cd concentrations, as well as low As exposure, relative to nutrient controls.Exposure to As and mixtures of metals (Pb þ Cd, Pb þ As) did not result in any significant increase inoxalate production compared to controls. The presence of a carbon source (glucose) in this study islikely to have been important for exudation of organic compounds. For the nutrient rich (þ1mMglucose) metal treatments exposure to Pb and Cd mainly increased exudation of oxalate and total aminoacids. Production of dissolved monosaccharides, as well as DOC, did not increase significantly in responseto metal exposure, irrespective of nutrient conditions. This may be explained by re-absorption ofthe organic compounds by the mycelium or by the fact that metals had no effect on exudation of thesecompounds.

Place, publisher, year, edition, pages
Amsterdam: Elsevier , 2008. Vol. 40, no 9, 2225-2236 p.
Keyword [en]
Amino acids, Ectomycorrhiza, Exudation, Fungi, LMWOA, Metals, Oxalate, Pure culture, Saprotrophic fungi
National Category
Natural Sciences
Research subject
Environmental Chemistry
Identifiers
URN: urn:nbn:se:oru:diva-11838DOI: 10.1016/j.soilbio.2008.04.016OAI: oai:DiVA.org:oru-11838DiVA: diva2:351510
Available from: 2010-09-14 Created: 2010-09-14 Last updated: 2017-12-12Bibliographically approved
In thesis
1. Impact of root and mycorrhizal exudation on soil carbon fluxes: influence of elevated CO2 and metals
Open this publication in new window or tab >>Impact of root and mycorrhizal exudation on soil carbon fluxes: influence of elevated CO2 and metals
2009 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The thesis concerns the behavior of root and ectomycorrhizal (ECM) exudates. In particular, the dynamics of soluble low molecular weight (LMW) organic compounds such as organic acids (LMWOAs), amino acids, monosaccharides, and dissolved organic carbon (DOC) have been studied. Our knowledge of exudation rates for tree roots and especially associated ECM is limited, and also factors influencing exudation rates. Two environmental factors, metal stress and elevated atmospheric CO2 level, have been investigated. Both are of great environmental concern, but function in different ways (detoxification and C allocation) and may be highly important for the C flux caused by root/ECM exudation. The project has been carried out with mycorrhizal and nonmycorrhizal (NM) Scots pine seedlings, or saprotrophic fungi, under both sterile and non-sterile (soil) conditions. Analytical determination of exudates and calculation of exudation rates have been major tools for assessment. Assessing the possibility of using naturally occurring chelating agents (e.g. citrate and oxalate) for bioremediation of metals contaminated soils and development and validation of analytical techniques have been additional foci. The results show that from soil-living fungi and ectomycorrhizal roots exudation rates of especially LMWOAs increase significantly at Cd and Pb stress (1-100 μM), while As (as arsenate) and mixtures of metals with As have little effect. The impact of ECM fungi is large and much higher exudation rates are found when the symbionts are present both for controls and metal treatments compared to NM plants. In soil systems there was a significant mobilization of metals from soils under presence of saprotrophic fungi. Both N as well as elevated CO2 (700 ppm) causes sizable increases in exudation rates, independent of biomass, and is a finding that suggests that the availability of easily degradable carbon in soil raises, which may be highly important for the carbon flux in soil. Mycorrhizal seedlings (10 months old) increased total soil respiration ~50% compared to controls without plants in non-sterile soil systems. Key words: amino acids, 13C, carbon cycle, ectomycorrhiza, elevated CO2, exudation, DOC, LMWOA, metal stress, monosaccharides, oxalate, Pinus sylvestris, saprotrophic fungi, soil respiration

Place, publisher, year, edition, pages
Örebro: Örebro universitet, 2009. 68 p.
Series
Örebro Studies in Environmental Science, ISSN 1650-6278 ; 14
Keyword
amino acids, 13C, carbon cycle, ectomycorrhiza, elevated CO2, exudation, DOC, LMWOA, metal stress, monosaccharides, oxalate, Pinus sylvestris, saprotrophic fungi, soil respiration
National Category
Natural Sciences Environmental Sciences
Research subject
Enviromental Science
Identifiers
urn:nbn:se:oru:diva-11848 (URN)978-91-7668-692-8 (ISBN)
Public defence
2009-11-13, Hörsal HSM, Fakultetsgatan 1, Örebro, 11:15 (English)
Opponent
Supervisors
Available from: 2010-09-15 Created: 2010-09-15 Last updated: 2017-10-18Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text

Authority records BETA

Johansson, Emma M.van Hees, Patrick A. W.

Search in DiVA

By author/editor
Johansson, Emma M.van Hees, Patrick A. W.
By organisation
School of Science and Technology
In the same journal
Soil Biology and Biochemistry
Natural Sciences

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 130 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf