Bödeker, Inga
- Southern Swedish Forest Research Centre, Swedish University of Agricultural Sciences
- Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences
Abstract
In northern forests, belowground sequestration of nitrogen (N) in complex organic pools restricts nutrient availability to plants. Oxidative extracellular enzymes produced by ectomycorrhizal fungi may aid plant N acquisition by providing access to N in macromolecular complexes. We test the hypotheses that ectomycorrhizal Cortinarius species produce Mn-dependent peroxidases, and that the activity of these enzymes declines at elevated concentrations of inorganic N.In a boreal pine forest and a sub-arctic birch forest, Cortinarius DNA was assessed by 454-sequencing of ITS amplicons and related to Mn-peroxidase activity in humus samples with- and without previous N amendment. Transcription of Cortinarius Mn-peroxidase genes was investigated in field samples. Phylogenetic analyses of Cortinarius peroxidase amplicons and genome sequences were performed.We found a significant co-localization of high peroxidase activity and DNA from Cortinarius species. Peroxidase activity was reduced by high ammonium concentrations. Amplification of mRNA sequences indicated transcription of Cortinarius Mn-peroxidase genes under field conditions. The Cortinarius glaucopus genome encodes 11 peroxidases - a number comparable to many white-rot wood decomposers.These results support the hypothesis that some ectomycorrhizal fungi - Cortinarius species in particular - may play an important role in decomposition of complex organic matter, linked to their mobilization of organically bound N.
Keywords
carbon sequestration; Class II peroxidases; decomposition; ectomycorrhizal fungi; high throughput sequencing; nitrogen limitation; priming effect; transcription
Published in
New Phytologist
2014, volume: 203, number: 1, pages: 245-256
SLU Authors
Clemmensen, Karina
- Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences
- Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences
Olson, Åke
- Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences
- Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences
Lindahl, Björn
- Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences
- Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences
UKÄ Subject classification
Microbiology
Forest Science
Publication identifier
- DOI: https://doi.org/10.1111/nph.12791
Permanent link to this page (URI)
https://res.slu.se/id/publ/53490