Ectomycorrhizal <i><scp>C</scp>ortinarius</i> species participate in enzymatic oxidation of humus in northern forest ecosystems

Bödeker, Inga T. M.; Clemmensen, Karina E.; Boer, Wietse de; Martin, Francis; Olson, Åke; Lindahl, Björn D.

doi:10.1111/nph.12791

Cited by 269 publications

(266 citation statements)

References 55 publications

Supporting

Mentioning

249

Contrasting

Unclassified

Order By: Relevance

“…The genus Cortinarius can be important in the decomposition of complex organic matter and may mobilize organically bound N in boreal forest soils (75). This genus can also possess genes needed to degrade lignin-like recalcitrant organic substrates (75). Species of the ECM genus Piloderma are abundant in coniferous forests (76) and favor low-N conditions (77).…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Fungal Community Shifts in Structure and Function across a Boreal Forest Fire Chronosequence

Sun

Santalahti

Pumpanen

et al. 2015

Appl Environ Microbiol

129

View full text Add to dashboard Cite

Forest fires are a common natural disturbance in forested ecosystems and have a large impact on the microbial communities in forest soils. The response of soil fungal communities to forest fire is poorly documented. Here, we investigated fungal community structure and function across a 152-year boreal forest fire chronosequence using high-throughput sequencing of the internal transcribed spacer 2 (ITS2) region and a functional gene array (GeoChip). Our results demonstrate that the boreal forest soil fungal community was most diverse soon after a fire disturbance and declined over time. The differences in the fungal communities were explained by changes in the abundance of basidiomycetes and ascomycetes. Ectomycorrhizal (ECM) fungi contributed to the increase in basidiomycete abundance over time, with the operational taxonomic units (OTUs) representing the genera Cortinarius and Piloderma dominating in abundance. Hierarchical cluster analysis by using gene signal intensity revealed that the sites with different fire histories formed separate clusters, suggesting differences in the potential to maintain essential biogeochemical soil processes. The site with the greatest biological diversity had also the most diverse genes. The genes involved in organic matter degradation in the mature forest, in which ECM fungi were the most abundant, were as common in the youngest site, in which saprotrophic fungi had a relatively higher abundance. This study provides insight into the impact of fire disturbance on soil fungal community dynamics. Boreal forest soils play an important role in the global carbon cycle (1) and are a net sink for atmospheric CO 2 (2, 3). Approximately 16% of the terrestrial carbon (C) stock is estimated to be stored in the boreal forest ecosystem (1). Fire is a natural disturbance in most forest ecosystems (4), and about 1% of the boreal forest burns annually (5). The frequency of forest fires in the northern boreal zone is expected to increase because of rising temperatures and more frequent dry periods resulting from ongoing climate change (6).Soil microbes perform essential ecological functions in forested ecosystems via nutrient cycling and decomposition of organic matter. Microbial activities control the turnover of organic C in soil and thus contribute to global C cycling (7). Fungi are the predominant decomposers in boreal soils and play a central role in the turnover of carbon and nitrogen (8). Ectomycorrhizal fungi form symbioses with both trees and ground vegetation in boreal forests. Many species of ground vegetation can additionally form symbioses with ericoid mycorrhizal fungi. Boreal forest ecosystem productivity is linked to plant nutrient acquisition from the microbial community via soil organic matter (SOM) decomposition. Forest fires result in the loss of mycorrhizal host plants and may modify the SOM chemistry, leading to dramatic changes in soil microbial activity (9, 10). Fire disturbance often increases soil pH and causes changes in soil temperature due to loss of canopy cover, bo...

show abstract

Section: Discussionmentioning

confidence: 99%

“…This dominance strongly contributes to the low diversity and evenness at the 152y site. The genus Cortinarius can be important in the decomposition of complex organic matter and may mobilize organically bound N in boreal forest soils (75). This genus can also possess genes needed to degrade lignin-like recalcitrant organic substrates (75).…”

Section: Discussionmentioning

confidence: 99%

Fungal Community Shifts in Structure and Function across a Boreal Forest Fire Chronosequence

Sun

Santalahti

Pumpanen

et al. 2015

Appl Environ Microbiol

129

View full text Add to dashboard Cite

show abstract

“…They are portrayed as mutualists trading host photoassimilates for nutrients and having limited capacity to decompose soil lignocellulose 1-3 , as a result of their reduced repertoire of PCWDEs 4-6 . However, recent studies are challenging this view [7][8][9][10] . An improved understanding of the ability of ECM fungi to decompose lignocellulose is needed to resolve mechanisms of nutrient cycling in forests.…”

mentioning

confidence: 99%

“…In contrast, H. cylindrosporum has three POD genes encoding manganese peroxidases ( Supplementary Fig. 4), thus suggesting that it may possess ligninolytic capabilities similar to those in Cortinarius glaucopus 10 .…”

mentioning

confidence: 99%

Convergent losses of decay mechanisms and rapid turnover of symbiosis genes in mycorrhizal mutualists

Kohler¹,

Kuo²,

Nagy³

et al. 2015

Nat Genet

Self Cite

900

1,063

View full text Add to dashboard Cite

l e t t e r sTo elucidate the genetic bases of mycorrhizal lifestyle evolution, we sequenced new fungal genomes, including 13 ectomycorrhizal (ECM), orchid (ORM) and ericoid (ERM) species, and five saprotrophs, which we analyzed along with other fungal genomes. Ectomycorrhizal fungi have a reduced complement of genes encoding plant cell walldegrading enzymes (PCWDEs), as compared to their ancestral wood decayers. Nevertheless, they have retained a unique array of PCWDEs, thus suggesting that they possess diverse abilities to decompose lignocellulose. Similar functional categories of nonorthologous genes are induced in symbiosis. Of induced genes, 7-38% are orphan genes, including genes that encode secreted effector-like proteins. Convergent evolution of the mycorrhizal habit in fungi occurred via the repeated evolution of a 'symbiosis toolkit', with reduced numbers of PCWDEs and lineage-specific suites of mycorrhiza-induced genes.Fungi are often described as either saprotrophs, which degrade complex organic substrates, or biotrophs, which obtain carbon compounds from living hosts. Among the latter, ECM fungi provide crucial ecological services in interacting with forest trees. They are portrayed as mutualists trading host photoassimilates for nutrients and having limited capacity to decompose soil lignocellulose 1-3 , as a result of their reduced repertoire of PCWDEs 4-6 . However, recent studies are challenging this view [7][8][9][10] . An improved understanding of the ability of ECM fungi to decompose lignocellulose is needed to resolve mechanisms of nutrient cycling in forests. The ECM lifestyle in Laccaria bicolor is associated with the expression of new mycorrhizainduced small secreted proteins (MiSSPs) that are required for establishment of symbiosis 11,12 . Mycorrhizal symbioses have arisen repeatedly during fungal evolution and include not only ECM associations but also those with ERM and ORM mycorrhizae 13 . It is not known whether these symbioses share the genomic features found in L. bicolor 4 and Tuber melanosporum 5 . Here we assess whether there Convergent losses of decay mechanisms and rapid turnover of symbiosis genes in mycorrhizal mutualists

show abstract

“…In the reference forests with intact organic layer, EMF communities of sapling roots were significantly more diverse and even, consisting of typical coniferous forest symbiont species, such as Piloderma, Cortinarius and Russula (Hansen and Knudsen, 1992), which are suggested to mobilize organically bound nutrients from soil humus (Buée et al, 2007;Bö deker et al, 2014;Velmala et al, 2014). In the intact forest soil, trees and saplings are typically connected by a shared EMF mycelial network (Simard et al, 2012).…”

Section: Discussionmentioning

confidence: 99%

Short-term impacts of energy wood harvesting on ectomycorrhizal fungal communities of Norway spruce saplings

Huusko

Tarvainen²,

Saravesi

et al. 2014

The ISME Journal

View full text Add to dashboard Cite

The increased demand for harvesting energy wood raises questions about its effects on the functioning of the forest ecosystems, soil processes and biodiversity. Impacts of tree stump removal on ectomycorrhizal fungal (EMF) communities of Norway spruce saplings were studied with 454-pyrosequencing in a 3-year field experiment replicated in 3 geographical areas. This is possibly the most thorough investigation of EMF communities associated with saplings grown on sites subjected to energy wood harvesting. To separate impacts of tree stump and logging residue removal on EMF and plant variables, we used three harvesting treatments with increasing complexity from patch mounding alone (P) to patch mounding combined with logging residue removal (RP), and patch mounding combined with both logging residue and stump removal (SRP). Saplings grown in uncut forests (F) served as references for harvesting treatments. A majority of sequences (492%) and operational taxonomic units (OTUs, 55%) were assigned as EMF. EMF OTU richness, fungal community composition or sapling growth did not differ between harvesting treatments (P, RP and SRP), while EMF OTU richness, diversity and evenness were highest and sapling growth lowest in the undisturbed reference forests (F). The short study period may partially explain the similarities in fungal and sapling variables in different harvesting treatments. In conclusion, our results indicate that neither stump removal nor logging residue removal have significant additional negative impacts on EMF communities or growth of Norway spruce saplings in the short-term compared with the impacts of more conventional harvesting methods, including clear cutting and patch mounding.

show abstract

Ectomycorrhizal Cortinarius species participate in enzymatic oxidation of humus in northern forest ecosystems

Cited by 269 publications

References 55 publications

Fungal Community Shifts in Structure and Function across a Boreal Forest Fire Chronosequence

Fungal Community Shifts in Structure and Function across a Boreal Forest Fire Chronosequence

Convergent losses of decay mechanisms and rapid turnover of symbiosis genes in mycorrhizal mutualists

Short-term impacts of energy wood harvesting on ectomycorrhizal fungal communities of Norway spruce saplings

Contact Info

Product

Resources

About