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1.
J Fungi (Basel) ; 9(9)2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37755050

RESUMO

Thirty-one alpine species of Cortinarius (Agaricales, Cortinariaceae) were described from the alpine zone of the Alps during the second half of the XX century, by the Swiss mycologist Jules Favre, and by the French mycologists Denise Lamoure and Marcel Bon. Notoriously difficult to identify by macro- and microscopical characters, most of these species, which belong to subgen. Telamonia, have been thoroughly revised in global publications based on type sequencing. Recent surveys in the alpine areas of France (Savoie) and Italy (Lombardy), as well as the sequencing of D. Lamoure's collections, identified three new species that are here described and illustrated: C. dryadophilus in sect. Castanei, C. infidus in sect. Verni, and C. saniosopygmaeus in sect. Saniosi. The holotypes of C. caesionigrellus Lamoure and C. paleifer var. brachyspermus Lamoure could be sequenced. A recent collection of the former is described and illustrated here for the first time, and based on available data, the latter name is recombined as Cortinarius flexipes var. brachyspermus comb. nov. Lastly, C. argenteolilacinus var. dovrensis is reported from the alpine zone for the first time and a new combination, Thaxterogaster dovrensis comb. & stat. nov. is introduced in the present work.

3.
J Fungi (Basel) ; 8(9)2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36135651

RESUMO

Large datasets are highly valuable resources to investigate multi-scale patterns of organisms, and lay foundations for citizen science-based conservation strategies. Here, we used 1,043,262 records from 1708 to 2021 to explore the geography, taxonomy, ecology and distribution patterns of 11,556 fungal taxa in metropolitan France. Our analysis reveals a four-phase pattern of temporal recording, with a main contribution of post-1977 observations in relation with the structuration of associative mycology. The dataset shows an uneven geography of fungal recording. Four clusters of high-intensity sampling scattered across France contrast with poorly documented areas, including the Mediterranean. Basidiomycota and Agaricales highly dominate the dataset, accounting for 88.8 and 50.4% of records, respectively. The dataset is composed of many rare taxa, with 61.2% of them showing fewer than 100 records, and 20.5% recorded only once. The analysis of metadata brings to light a preponderance of the mycorrhizal guild (44.6%), followed by litter saprotrophs (31.6%) and wood saprotrophs (18.1%). Highly documented forests (76.3% of records) contrast with poorly investigated artificial (6.43%) and open habitats (10.1%). This work provides the first comprehensive overview of fungal diversity in France and identifies the Mediterranean area and open habitats as priorities to integrate into a global strategy for fungal conservation in France.

4.
New Phytol ; 236(2): 698-713, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35811430

RESUMO

The biogeography of neotropical fungi remains poorly understood. Here, we reconstruct the origins and diversification of neotropical lineages in one of the largest clades of ectomycorrhizal fungi in the globally widespread family Russulaceae. We inferred a supertree of 3285 operational taxonomic units, representing worldwide internal transcribed spacer sequences. We reconstructed biogeographic history and diversification and identified lineages in the Neotropics and adjacent Patagonia. The ectomycorrhizal Russulaceae have a tropical African origin. The oldest lineages in tropical South America, most with African sister groups, date to the mid-Eocene, possibly coinciding with a boreotropical migration corridor. There were several transatlantic dispersal events from Africa more recently. Andean and Central American lineages mostly have north-temperate origins and are associated with North Andean uplift and the general north-south biotic interchange across the Panama isthmus, respectively. Patagonian lineages have Australasian affinities. Diversification rates in tropical South America and other tropical areas are lower than in temperate areas. Neotropical Russulaceae have multiple biogeographic origins since the mid-Eocene involving dispersal and co-migration. Discontinuous distributions of host plants may explain low diversification rates of tropical lowland ectomycorrhizal fungi. Deeply diverging neotropical fungal lineages need to be better documented.


Assuntos
Basidiomycota , Micorrizas , Micorrizas/genética , Filogenia , Filogeografia , América do Sul
5.
J Fungi (Basel) ; 8(6)2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35736106

RESUMO

We studied the taxonomy of Pluteus insidiosus and similar species using morphological and molecular (nrITS, TEF1-α) data, including a detailed study of the type collection of P. insidiosus. Based on our results, we recognize five species in this group: P. insidiosus sensu stricto and four other taxa: P. assimilatus; P. farensis; P. flavostipitatus; and P. pseudoinsidiosus; described here as new. All these taxa are distinct from each other based on molecular data, but some of them are semi-cryptic based on morphology and co-occur in the Palaearctic region. An additional molecular lineage, phylogenetically separates from the P. insidiosus complex, but with many morphological similarities, was recognized in the molecular phylogenies. Based on the revision of available type collections, the name Pluteus reisneri Velen., was adopted for this Clade. Pluteus reisneri was validly published in 1921, but it has barely been used since its original description. A modern epitype, with molecular data, was selected for P. reisneri.

6.
Biology (Basel) ; 11(5)2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35625498

RESUMO

In Europe, amatoxin-containing mushrooms are responsible for most of the deadly poisonings caused by macrofungi. The present work presents a multidisciplinary revision of the European species of Amanita sect. Phalloideae based on morphology, phylogeny, epidemiology, and biochemistry of amatoxins and phallotoxins. Five distinct species of this section have been identified in Europe to date: A. phalloides, A. virosa, A. verna, the recently introduced North American species A. amerivirosa, and A. vidua sp. nov., which is a new name proposed for the KOH-negative Mediterranean species previously described as A. verna or A. decipiens by various authors. Epitypes or neotypes are selected for species lacking suitable reference collections, namely A. verna and A. virosa. Three additional taxa, Amanita decipiens, A. porrinensis, and A. virosa var. levipes are here considered later heterotypic synonyms of A. verna, A. phalloides, and A. amerivirosa, respectively.

7.
Commun Biol ; 4(1): 871, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34267314

RESUMO

Fungal biotechnology is set to play a keystone role in the emerging bioeconomy, notably to address pollution issues arising from human activities. Because they preserve biological diversity, Biological Resource Centres are considered as critical infrastructures to support the development of biotechnological solutions. Here, we report the first large-scale phenotyping of more than 1,000 fungal strains with evaluation of their growth and degradation potential towards five industrial, human-designed and recalcitrant compounds, including two synthetic dyes, two lignocellulose-derived compounds and a synthetic plastic polymer. We draw a functional map over the phylogenetic diversity of Basidiomycota and Ascomycota, to guide the selection of fungal taxa to be tested for dedicated biotechnological applications. We evidence a functional diversity at all taxonomic ranks, including between strains of a same species. Beyond demonstrating the tremendous potential of filamentous fungi, our results pave the avenue for further functional exploration to solve the ever-growing issue of ecosystems pollution.


Assuntos
Biotecnologia/métodos , Corantes/metabolismo , Fungos/metabolismo , Microbiologia Industrial/métodos , Lignina/metabolismo , Plásticos/metabolismo , Ascomicetos/classificação , Ascomicetos/genética , Ascomicetos/metabolismo , Basidiomycota/classificação , Basidiomycota/genética , Basidiomycota/metabolismo , Fungos/classificação , Fungos/genética , Variação Genética , Geografia , Humanos , Fenótipo , Filogenia , Especificidade da Espécie
8.
Nat Commun ; 11(1): 1509, 2020 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-32198346

RESUMO

Nonsense mutations cause about 10% of genetic disease cases, and no treatments are available. Nonsense mutations can be corrected by molecules with nonsense mutation readthrough activity. An extract of the mushroom Lepista inversa has recently shown high-efficiency correction of UGA and UAA nonsense mutations. One active constituent of this extract is 2,6-diaminopurine (DAP). In Calu-6 cancer cells, in which TP53 gene has a UGA nonsense mutation, DAP treatment increases p53 level. It also decreases the growth of tumors arising from Calu-6 cells injected into immunodeficient nude mice. DAP acts by interfering with the activity of a tRNA-specific 2'-O-methyltransferase (FTSJ1) responsible for cytosine 34 modification in tRNATrp. Low-toxicity and high-efficiency UGA nonsense mutation correction make DAP a good candidate for the development of treatments for genetic diseases caused by nonsense mutations.


Assuntos
2-Aminopurina/análogos & derivados , 2-Aminopurina/farmacologia , Códon sem Sentido/efeitos dos fármacos , Descoberta de Drogas , Ensaios de Seleção de Medicamentos Antitumorais , Mutação/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genes p53/genética , Células HEK293 , Células HeLa , Humanos , Lepisma/química , Camundongos , Camundongos Nus , RNA de Transferência/genética , tRNA Metiltransferases/metabolismo
9.
Data Brief ; 25: 104115, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31453275

RESUMO

The data presented here was obtained during a decade-long macromycete inventory on the island of Cyprus and is supplementary to the research article "Present status and future of boletoid fungi (Boletaceae) on the island of Cyprus: cryptic and threatened diversity unravelled by ten-year study" [1]. A new, rainfall-based sampling protocol for documenting fungal diversity in Mediterranean ecosystems, is described in detail.

10.
PLoS One ; 14(2): e0211388, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30726262

RESUMO

Taxonomy of Geastrum species in the neotropics has been subject to divergent opinions among specialists. In our study, type collections were reassessed and compared with recent collections in order to delimit species in Geastrum, sect. Myceliostroma, subsect. Epigaea. A thorough review of morphologic features combined with barcode and phylogenetic analyses (ITS and LSU nrDNA) revealed six new species (G. neoamericanum, G. rubellum, G. brunneocapillatum, G. baculicrystallum, G. rubropusillum and G. courtecuissei). In additon, the presence of hairs on the exoperidium, a commonly used feature to diagnose Geastrum species, proved to be ineffective because it is a derived character within subsect. Epigaea.


Assuntos
Basidiomycota/classificação , Basidiomycota/genética , América , Basidiomycota/citologia , Código de Barras de DNA Taxonômico , DNA Fúngico/genética , Variação Genética , Filogenia , Filogeografia , Especificidade da Espécie , Clima Tropical
11.
IMA Fungus ; 10: 5, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32647614

RESUMO

The Russula globispora lineage is a morphologically and phylogenetically well-defined group of ectomycorrhizal fungi occurring in various climatic areas. In this study we performed a multi-locus phylogenetic study based on collections from boreal, alpine and arctic habitats of Europe and Western North America, subalpine collections from the southeast Himalayas and collections from subtropical coniferous forests of Pakistan. European and North American collections are nearly identical and probably represent a single species named R. dryadicola distributed from the Alps to the Rocky Mountains. Collections from the southeast Himalayas belong to two distinct species: R. abbottabadensis sp. nov. from subtropical monodominant forests of Pinus roxburghii and R. tengii sp. nov. from subalpine mixed forests of Abies and Betula. The results suggest that speciation in this group is driven by a climate disjunction and adaptation rather than a host switch and geographical distance.

12.
New Phytol ; 219(1): 336-349, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29377140

RESUMO

We investigated whether the diversity, endemicity and specificity of alder symbionts could be changed by isolation in a Mediterranean glacial refugium. We studied both ectomycorrhizal (EM) fungi and nitrogen-fixing actinobacteria associated with alders, and compared their communities in Corsica and on the European continent. Nodules and root tips were sampled on the three alder species present in Corsica and continental France and Italy. Phylogenies based on internal transcribed spacer (ITS) and a multilocus sequence analysis approach were used to characterize fungal and Frankia species, respectively. Patterns of diversity, endemism and specialization were compared between hosts and regions for each symbiont community. In Corsica, communities were not generally richer than on the mainland. The species richness per site depended mainly on host identity: Alnus glutinosa and Alnus cordata hosted richer Frankia and EM communities, respectively. Half of the Frankia species were endemic to Corsica against only 4% of EM species. Corsica is not a hotspot of diversity for all alder symbionts but sustains an increased frequency of poor-dispersers such as hypogeous fungi. Generalist EM fungi and host-dependent profusely sporulating (Sp+) Frankia were abundantly associated with Corsican A. cordata, a pattern related to a more thermophilic and xerophylic climate and to the co-occurrence with other host trees.


Assuntos
Alnus/microbiologia , Biodiversidade , Raízes de Plantas/microbiologia , França , Frankia/genética , Frankia/fisiologia , Itália , Micorrizas/fisiologia , Filogenia , Nódulos Radiculares de Plantas/microbiologia , Microbiologia do Solo , Simbiose/fisiologia
13.
IMA Fungus ; 9: 271-290, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30622883

RESUMO

In this study, eight species of Chroogomphus are recognized from Europe: C. britannicus, C. aff. filiformis 1, C. fulmineus, C. cf. helveticus, C. mediterraneus, C. cf. purpurascens, C. rutilus, and C. subfulmineus. Different candidates for the application of the name C. rutilus are evaluated and the best fit to the description is selected; lecto- and epitypes are chosen to fix the name. Chroogomphus fulmineus and C. mediterraneus are also epitypified and a new species, C. subfulmineus, is described. The infrageneric classification is revised and a new subgenus Siccigomphus and three new sections, Confusi, Filiformes, and Fulminei are introduced. The former sections Chroogomphus and Floccigomphus are elevated to subgeneric level. Comparison of the ITS regions (nuc rDNA ITS1-5.8S-ITS2) of all species studied shows that there is a minimum interspecific difference of 1.5 %, with the exception of the two species belonging to sect. Fulminei which differ by a minimum of 0.9 %. Ecological specimen data indicate that species of Chroogomphus form basidiomes under members of Pinaceae, with a general preference for species of Pinus. Five European species have been recorded under Picea, while Abies and Larix have also been recorded as tree associates, although the detailed nutritional relationships of the genus, involving other suilloid fungi in particular, have yet to be fully clarified.

14.
PeerJ ; 5: e3479, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28729950

RESUMO

BACKGROUND: Recent climatic history has strongly impacted plant populations, but little is known about its effect on microbes. Alders, which host few and specific symbionts, have high genetic diversity in glacial refugia. Here, we tested the prediction that communities of root symbionts survived in refugia with their host populations. We expected to detect endemic symbionts and a higher species richness in refugia as compared to recolonized areas. METHODS: We sampled ectomycorrhizal (EM) root tips and the nitrogen-fixing actinomycete Frankia communities in eight sites colonized by Alnus glutinosa subsp. barbata close to the Caucasus in Georgia. Three sites were located in the Colchis, one major Eurasian climatic refugia for Arcto-Tertiary flora and alders, and five sites were located in the recolonized zone. Endemic symbionts and plant ITS variants were detected by comparing sequences to published data from Europe and another Tertiary refugium, the Hyrcanian forest. Species richness and community structure were compared between sites from refugia and recolonized areas for each symbionts. RESULTS: For both symbionts, most MOTUs present in Georgia had been found previously elsewhere in Europe. Three endemic Frankia strains were detected in the Colchis vs two in the recolonized zone, and the five endemic EM fungi were detected only in the recolonized zone. Frankia species richness was higher in the Colchis while the contrary was observed for EM fungi. Moreover, the genetic diversity of one alder specialist Alnicola xanthophylla was particularly high in the recolonized zone. The EM communities occurring in the Colchis and the Hyrcanian forests shared closely related endemic species. DISCUSSION: The Colchis did not have the highest alpha diversity and more endemic species, suggesting that our hypothesis based on alder biogeography may not apply to alder's symbionts. Our study in the Caucasus brings new clues to understand symbioses biogeography and their survival in Tertiary and ice-age refugia, and reveals that isolated host populations could be of interest for symbiont diversity conservation.

15.
Fungal Biol ; 120(5): 711-28, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27109368

RESUMO

Paxillus rubicundulus P.D. Orton has been shown to be a complex of at least three ectomycorrhizal taxa strictly associated with alders (Alnus) in Europe, P. rubicundulus s. str., and two undescribed clades. To assess the taxonomic status of these three clades and their phylogenetic relationships, phylogenetic analyses of two independent gene regions (ITS and gpd), combined with macro- and micromorphological comparisons of genetically identified specimens, were carried out. A total of 85 sequences were successfully obtained from basidiomata and alder mycorrhizae collected in France and Algeria and combined with GenBank and UNITE sequences. The phylogenetic results and estimates of genetic diversity confirmed that the three clades are distinct species, often found in sympatry. As a result, P. rubicundulus s. str. was redefined based on the revision of type material, and Paxillus adelphus and Paxillus olivellus are introduced as new Linnaean names. The often used name Paxillus filamentosus is rejected since it could not be applied to any of the new species. The three species are distinguished micromorphologically by spore size and shape. They are widely distributed in Europe, North Africa and western Asia; P. rubicundulus is rare, and all species have a limited host range.


Assuntos
Alnus/microbiologia , Basidiomycota/classificação , Basidiomycota/isolamento & purificação , Micorrizas/classificação , Micorrizas/isolamento & purificação , Filogenia , Argélia , Basidiomycota/genética , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , França , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/genética , Micorrizas/citologia , Micorrizas/genética , Análise de Sequência de DNA
16.
Front Plant Sci ; 6: 881, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26539201

RESUMO

The ectomycorrhizal (ECM) symbiosis connects mutualistic plants and fungal species into bipartite networks. While links between one focal ECM plant and its fungal symbionts have been widely documented, systemic views of ECM networks are lacking, in particular, concerning the ability of fungal species to mediate indirect ecological interactions between ECM plant species (projected-ECM networks). We assembled a large dataset of plant-fungi associations at the species level and at the scale of Corsica using molecular data and unambiguously host-assigned records to: (i) examine the correlation between the number of fungal symbionts of a plant species and the average specialization of these fungal species, (ii) explore the structure of the plant-plant projected network and (iii) compare plant association patterns in regard to their position along the ecological succession. Our analysis reveals no trade-off between specialization of plants and specialization of their partners and a saturation of the plant projected network. Moreover, there is a significantly lower-than-expected sharing of partners between early- and late-successional plant species, with fewer fungal partners for early-successional ones and similar average specialization of symbionts of early- and late-successional plants. Our work paves the way for ecological readings of Mediterranean landscapes that include the astonishing diversity of below-ground interactions.

17.
Mycologia ; 107(2): 359-82, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25550303

RESUMO

Applying early names, with or without original material, to genealogical species is challenging. For morels this task is especially difficult because of high morphological stasis and high plasticity of apothecium color and shape. Here we propose a nomenclatural revision of true morels (Morchella, Pezizales) from Europe and North America, based on molecular phylogenetic analyses of portions of the genes for RNA polymerase II largest subunit (RPB1) and second largest subunit (RPB2), translation elongation factor-1α (TEF1), the nuc rDNA region encompassing the internal transcribed spacers 1 and 2, along with the 5.8S rDNA (ITS), and partial nuc 28S rDNA D1-D2 domains (28S). The 107 newly sequenced collections were from both continents, including 48 types, together with previously published sequences. Names are applied to 30 of the 65 currently recognized genealogical species. Results of the present study revealed that the number of Morchella species in Europe (n = 21) is nearly identical to that in North America (n = 22). Only seven species were found on both continents, consistent with previous reports of high continental endemism within the genus. Presently it is not possible to tell whether the transoceanic disjunctions were due to human activities, migration across a Bering land bridge or long-distance dispersal. In an effort to stabilize the taxonomy, due in part to the recent publication of synonyms for 11 of the species, accepted names are presented together with their corresponding later synonyms. A new subclade that includes holotypes of M. castanea and M. brunneorosea is identified in sect. Morchella (Esculenta Clade). Lectotypes for Morchella deliciosa, M. eximia and M. tridentina are designated here, as well as epitypes for M. dunalii, M. eximia, M. purpurascens and M. vulgaris. Morchella conica was determined to be illegitimate, and further research is required to determine the identity of M. elata and M. inamoena.


Assuntos
Ascomicetos/genética , Ascomicetos/isolamento & purificação , Evolução Molecular , Ascomicetos/classificação , Europa (Continente) , Atividades Humanas , Humanos , Dados de Sequência Molecular , América do Norte , Filogenia
18.
PLoS One ; 8(5): e63926, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23704957

RESUMO

Mycophiles forage for and pick vast quantities of a wide variety of wild mushroom species. As a result, mushroom intoxications are comparatively frequent in such countries with mycophiles. Thus, national governments are forced to release guidelines or enact legislation in order to ensure the safe commerce of wild mushrooms due to food safety concerns. It is in these guidelines and laws that one can observe whether a country is indeed mycophobic or mycophilic. Furthermore, these laws and guidelines provide valuable information on mushroom preferences and on the consumption habits of each country. As such we were interested in the questions as to whether mushroom consumption behaviour was different within Europe, and if it was possible to discover the typical or distinctive culinary preferences of Slavic or Romanic speaking people, people from special geographical regions or from different zones. This work is based on the analysis of edible mushroom lists available in specific guidelines or legislation related to the consumption and commerce of mushrooms in 27 European countries. The overall diversity of edible mushrooms authorised to be commercialised in Europe is very high. However, only 60 out of a total 268 fungal species can be cultivated. This highlights the importance of guidelines or legislation for the safe commerce of wild mushrooms. The species richness and composition of the mushrooms listed for commerce is very heterogeneous within Europe. The consumption behaviour is not only language-family-related, but is strongly influenced by geographical location and neighbouring countries. Indicator species were detected for different European regions; most of them are widespread fungi, and thus prove culture-specific preferences for these mushrooms. Our results highlight tradition and external input such as trade and cultural exchange as strong factors shaping mushroom consumption behaviour.


Assuntos
Agaricales/fisiologia , Comércio , Comportamento Alimentar , Guias como Assunto , Legislação como Assunto/economia , Biodiversidade , Europa (Continente) , Geografia , Humanos , Especificidade da Espécie
19.
New Phytol ; 198(4): 1228-1238, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23496225

RESUMO

· Global-scale analyses of ectomycorrhizal (ECM) fungi communities emphasize host plant families as the main drivers of diversity. This study aims to test, on Alnus-ECM communities, which fungi are said to be 'host-specific', to what extent host species, habitat and distance explain their alpha and beta diversity variations, and their specificity. · In France, ECM communities associated with two subgenera and five species of Alnus, were sampled on 165 trees from 39 lowland to subalpine sites. In all, 1178 internal transcribed spacer (ITS) sequences of ECM fungi clustered in 86 molecular operational taxonomic units (MOTUs). · The species richness was low but still variable, and the evenness of communities was lower on organic soils and in Corsica. Similarity between communities was influenced both by host, soil parameters, altitude and longitude, but not by climate and distance. A large majority of 'specific' fungi were shared between host species within a subgenus, and showed habitat preferences within the subgenus distribution range. · Our study confirms that Alnus ECM communities are low in diversity, highly conserved at a regional scale, and partly shared between congeneric host species. A large part of alpha and beta diversity variations remained unexplained, and other processes may shape these communities.


Assuntos
Alnus/microbiologia , Ecossistema , Geografia , Especificidade de Hospedeiro , Micorrizas/crescimento & desenvolvimento , Biodiversidade , França , Dados de Sequência Molecular , Análise Multivariada , Microbiologia do Solo
20.
BMC Evol Biol ; 11: 40, 2011 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-21306639

RESUMO

BACKGROUND: Mycorrhizal fungi form intimate associations with their host plants that constitute their carbon resource and habitat. Alnus spp. (Betulaceae) are known to host an exceptional species-poor and specialized ectomycorrhizal (ECM) fungal community compared to other tree species, but the host-specificity pattern and its significance in terms of fungal diversification and speciation remain poorly documented. The degree of parallel speciation, host switching, and patterns of biogeography were explored in the historical associations between alders and three ECM taxa of Basidiomycetes: Alnicola (Agaricales), Alpova (Boletales), and Lactarius (Russulales). The aim was to develop an evolutionary framework on host specificity and diversification of Basidiomycetes in this highly specialized plant-fungus symbiosis. RESULTS: Sporocarps of Alnicola (220), Lactarius (61) and Alpova (29) were collected from stands of the four European alder species (A. alnobetula including the endemic subsp. suaveolens in Corsica, A. cordata, A. glutinosa, A. incana) in Western Europe (mainly in France and Austria), from 1995 to 2009. Specimens were morphologically identified to the species level. From these, 402 sequences of four DNA regions (ITS, rpb2, gpd, and the V9 domain of the mit-SSU rDNA) were successfully obtained and analyzed in addition with 89 sequences available in GenBank and UNITE databases. Phylogenetic analyses were conducted on all sequence data sets (individual and combined) using maximum likelihood reconstruction and Bayesian inference. Fungal phylogenies are compared and discussed in relation to the host, with a focus on species boundaries by associating taxonomic, systematic and molecular information. CONCLUSIONS: Patterns of host specificity and phylogenies of Alnicola and Lactarius suggest coevolution as a basal factor of speciation in relation with the subgeneric diversification of Alnus, possibly due to the very selective pressure of the host. A second element of the historical associations between Alnus and its fungal symbionts is a host-dependent speciation (radiation without host change), here observed in Alnicola and Alpova in relation with Alnus subgen. Alnus. Finally host shifts from Alnus subgen. Alnus to A. alnobetula are found in most lineages of Alnicola (at least four times), Alpova (twice) and Lactarius (once), but they do not represent such a common event as could be expected by geographic proximity of trees from the two subgenera. However, active or very recent host extensions clearly occurred in Corsica, where some fungi usually associated with Alnus glutinosa on mainland Europe locally extend there to A. alnobetula subsp. suaveolens without significant genetic or morphological deviation.


Assuntos
Alnus/genética , Alnus/microbiologia , Especiação Genética , Micorrizas/classificação , Filogenia , Alnus/classificação , Basidiomycota/classificação , Basidiomycota/genética , Teorema de Bayes , DNA Fúngico/genética , DNA Mitocondrial/genética , DNA de Plantas/genética , DNA Espaçador Ribossômico/genética , Europa (Continente) , Funções Verossimilhança , Micorrizas/genética , Alinhamento de Sequência , Análise de Sequência de DNA , Especificidade da Espécie
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