首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Tuberculate ectomycorrhizae (TECM) are unique structures in which aggregates of ectomycorrhizal roots are encased in a covering of fungal hyphae. The function of TECM is unknown, but they probably enhance the nitrogen nutrition and disease resistance of host plants. Trees in the Pinaceae form TECM with species of Rhizopogon and Suillus (Suillineae, Boletales). Similar tubercules are found with diverse angiosperms, but their mycobionts have not been phylogenetically characterized. We collected TECM in Mexico and the USA that were similar to TECM in previous reports. We describe these TECM and identify both the plant and fungal symbionts. Plant DNA confirms that TECM hosts are Quercus species. ITS sequences from tubercules and sclerotia (hyphal aggregations that serve as survival structures) matched sporocarps of Boletus rubropunctus. Phylogenetic analyses confirm that this fungus belongs to the suborder Boletineae (Boletales). This is the first published report of TECM formation in the Boletineae and of sclerotia formation by a Boletus species. Our data suggest that the TECM morphology is an adaptive feature that has evolved separately in two suborders of Boletales (Suillineae and Boletineae) and that TECM formation is controlled by the mycobiont because TECM are found on distantly related angiosperm and gymnosperm host plants.  相似文献   

2.
Feng B  Xu J  Wu G  Zeng NK  Li YC  Tolgor B  Kost GW  Yang ZL 《PloS one》2012,7(5):e37567
The wild gourmet mushroom Boletus edulis and its close allies are of significant ecological and economic importance. They are found throughout the Northern Hemisphere, but despite their ubiquity there are still many unresolved issues with regard to the taxonomy, systematics and biogeography of this group of mushrooms. Most phylogenetic studies of Boletus so far have characterized samples from North America and Europe and little information is available on samples from other areas, including the ecologically and geographically diverse regions of China. Here we analyzed DNA sequence variation in three gene markers from samples of these mushrooms from across China and compared our findings with those from other representative regions. Our results revealed fifteen novel phylogenetic species (about one-third of the known species) and a newly identified lineage represented by Boletus sp. HKAS71346 from tropical Asia. The phylogenetic analyses support eastern Asia as the center of diversity for the porcini sensu stricto clade. Within this clade, B. edulis is the only known holarctic species. The majority of the other phylogenetic species are geographically restricted in their distributions. Furthermore, molecular dating and geological evidence suggest that this group of mushrooms originated during the Eocene in eastern Asia, followed by dispersal to and subsequent speciation in other parts of Asia, Europe, and the Americas from the middle Miocene through the early Pliocene. In contrast to the ancient dispersal of porcini in the strict sense in the Northern Hemisphere, the occurrence of B. reticulatus and B. edulis sensu lato in the Southern Hemisphere was probably due to recent human-mediated introductions.  相似文献   

3.
The Boletus edulis species complex includes ectomycorrhizal fungi producing edible mushrooms appreciated worldwide. However, species delineation is very difficult in these fungi, because it is based exclusively on a few, highly variable morphological features. As a consequence, a high number of taxa--including several varieties, subspecies and/or species sensu stricto--have been described in this species complex. In this paper we report on an extensive analysis of internal transcribed spacer of the nuclear rDNA region on a large sample of species of the B. edulis complex, mainly harvested in Italy, and representative of the European variability of this group. The molecular analysis allowed us to discriminate among and within B. edulis, B. aestivalis, B. pinophilus and B. aereus spp. and resolve their phylogenetic relationship.  相似文献   

4.
Boletus species belonging to the section Boletus are the most frequently eaten fungi among those harvested in natural conditions in Europe. This section groups 10 taxa which are hardly distinguishable on the basis of their morphology. Some of them have been shown to induce allergic IgE-mediated symptoms either through inhalation, ingestion or contact. Since questions relating to the presence of allergens in any of the species most in demand (B. edulis, B. aereus, B. pinophilus, B. aestivalis, all classified as B. edulis s.l.) remain open, together with the absence of tools which distinguish the species, we sequenced the ITS region of 28 Boletus samples and then we designed specific primers. These allowed the effective separation of the taxa. In addition, the phylogenetic tree obtained from the sequences alignment revealed that B. violaceofuscus, a spectacular Chinese fungus considered belonging to the section Boletus and often sold intermixed with B. edulis s.l. specimens, clusters outside the section Boletus.  相似文献   

5.
A study was conducted in a Castanea sativa forest that produces large quantities of the edible mushroom porcini (Boletus edulis sensu lato). The primary aim was to study porcini mycelia in the soil, and to determine if there were any possible ecological and functional interactions with other dominant soil fungi. Three different approaches were used: collection and morphological identification of fruiting bodies, morphological and molecular identification of ectomycorrhizae by rDNA-ITS sequence analyses and molecular identification of the soil mycelia by ITS clone libraries. Soil samples were taken directly under basidiomes of Boletus edulis, Boletus aestivalis, Boletus aereus and Boletus pinophilus. Thirty-nine ectomycorrhizal fungi were identified on root tips whereas 40 fungal species were found in the soil using the cloning technique. The overlap between above- and below-ground fungal communities was very low. Boletus mycelia, compared with other soil fungi, were rare and with scattered distribution, whereas their fruiting bodies dominated the above-ground fungal community. Only B. aestivalis ectomycorrhizae were relatively abundant and detected as mycelia in the soil. No specific fungus-fungus association was found. Factors triggering formation of mycorrhizae and fructification of porcini appear to be too complex to be simply explained on the basis of the amount of fungal mycelia in the soil.  相似文献   

6.
The family Cyprinidae is the largest freshwater fish group in the world, including over 200 genera and 2100 species. The phylogenetic relationships of major clades within this family are simply poorly understood, largely because of the overwhelming diversity of the group; however, several investigators have advanced different hypotheses of relationships that pre- and post-date the use of shared-derived characters as advocated through phylogenetic systematics. As expected, most previous investigations used morphological characters. Recently, mitochondrial DNA (mtDNA) sequences and combined morphological and mtDNA investigations have been used to explore and advance our understanding of species relationships and test monophyletic groupings. Limitations of these studies include limited taxon sampling and a strict reliance upon maternally inherited mtDNA variation. The present study is the first endeavor to recover the phylogenetic relationships of the 12 previously recognized monophyletic subfamilies within the Cyprinidae using newly sequenced nuclear DNA (nDNA) for over 50 species representing members of the different previously hypothesized subfamily and family groupings within the Cyprinidae and from other cypriniform families as outgroup taxa. Hypothesized phylogenetic relationships are constructed using maximum parsimony and Basyesian analyses of 1042 sites, of which 971 sites were variable and 790 were phylogenetically informative. Using other appropriate cypriniform taxa of the families Catostomidae (Myxocyprinus asiaticus), Gyrinocheilidae (Gyrinocheilus aymonieri), and Balitoridae (Nemacheilus sp. and Beaufortia kweichowensis) as outgroups, the Cyprinidae is resolved as a monophyletic group. Within the family the genera Raiamas, Barilius, Danio, and Rasbora, representing many of the tropical cyprinids, represent basal members of the family. All other species can be classified into variably supported and resolved monophyletic lineages, depending upon analysis, that are consistent with or correspond to Barbini and Leuciscini. The Barbini includes taxa traditionally aligned with the subfamily Cyprininae sensu previous morphological revisionary studies by Howes (Barbinae, Labeoninae, Cyprininae and Schizothoracinae). The Leuciscini includes six other subfamilies that are mainly divided into three separate lineages. The relationships among genera and subfamilies are discussed as well as the possible origins of major lineages.  相似文献   

7.
8.
We present a phylogenetic hypothesis and novel, rank-free classification for all extant species of softshell turtles (Testudines:Trionychidae). Our data set included DNA sequence data from two mitochondrial protein-coding genes and a approximately 1-kb nuclear intron for 23 of 26 recognized species, and 59 previously published morphological characters for a complimentary set of 24 species. The combined data set provided complete taxonomic coverage for this globally distributed clade of turtles, with incomplete data for a few taxa. Although our taxonomic sampling is complete, most of the modern taxa are representatives of old and very divergent lineages. Thus, due to biological realities, our sampling consists of one or a few representatives of several ancient lineages across a relatively deep phylogenetic tree. Our analyses of the combined data set converge on a set of well-supported relationships, which is in accord with many aspects of traditional softshell systematics including the monophyly of the Cyclanorbinae and Trionychinae. However, our results conflict with other aspects of current taxonomy and indicate that most of the currently recognized tribes are not monophyletic. We use this strong estimate of the phylogeny of softshell turtles for two purposes: (1) as the basis for a novel rank-free classification, and (2) to retrospectively examine strategies for analyzing highly homoplasious mtDNA data in deep phylogenetic problems where increased taxon sampling is not an option. Weeded and weighted parsimony, and model-based techniques, generally improved the phylogenetic performance of highly homoplasious mtDNA sequences, but no single strategy completely mitigated the problems of associated with these highly homoplasious data. Many deep nodes in the softshell turtle phylogeny were confidently recovered only after the addition of largely nonhomoplasious data from the nuclear intron.  相似文献   

9.
Nationalization and Globalization Trends in the Wild Mushroom Commerce of Italy with Emphasis on Porcini ( Boletus edulis and Allied Species). This paper presents an historical overview of wild mushroom commerce in Italy, with a focus on recent trends in the production of porcini (Boletus edulis and closely allied species). Over the past century, two major trends—nationalization and globalization—have been apparent in the wild mushroom commerce of Italy. First, a simplified national mushroom menu has emerged through processes of governmental regulation and culinary fashion, but it has come at the expense of differing, localized mushroom traditions which may suffer under the European Union’s free trade principles. Second, Italy has emerged as a focal point of a global market for a small number of mushroom species—particular porcini. While the name porcini has become synonymous with Italian cuisine, and in spite of a vibrant tradition of recreational mushroom collecting in Italy, most of the porcini commercially available in Italy or exported by Italy are no longer of Italian origin. Porcini and other mushrooms now flow into Italy from all over the world—especially from China and eastern Europe—and are then often exported as “Italian porcini.” This globalization of the wild mushroom trade, while offering significant income to rural producers and processors around the globe, has other effects as well, for example, a kind of national branding as “Italian” of globally-produced products, of which porcini is one, that is in direct opposition to some of the European Union’s rules for regional denominations.
Processi di Nazionalizzazione e Globalizzazione nel Commercio Italiano dei Funghi spontanei, con Particolare Riguardo ai Porcini ( Boletus edulis e Specie Affini). Questo articolo presenta una panoramica storica sul commercio dei funghi spontanei in Italia, con particolare riguardo alle recenti tendenze nella produzione dei porcini (Boletus edulis e specie affini). Nello scorso secolo si sono osservate due tendenze principali—di nazionalizzazione e di globalizzazione—nel commercio dei funghi spontanei in Italia. In primo luogo si è affermata nel territorio nazionale una tradizione limitata al consumo di un numero contenuto di specie, sia per effetto di alcune normative che di mode culinarie, ma ciò è avvenuto a discapito di tradizioni locali più ricche, che potrebbero ulteriormente risentire dei principi per il libero scambio all’interno dell’Unione Europea. In secondo luogo, l’Italia si è posta in evidenza come un punto nodale per il mercato globale di alcune specie fungine, in particolare dei porcini. Nonostante quest’ultimo termine sia tradizionalmente associato alla cucina italiana, e nonostante esista in Italia una vivace e radicata tradizione nella raccolta amatoriale dei funghi, la maggior parte dei porcini ivi commercializzati (allo stato fresco, essiccati o variamente conservati) o esportati verso altri paesi non sono più di origine locale. I porcini e altre specie fungine giungono attualmente in Italia da ogni parte del mondo—in modo particolare dalla Cina e dall’Europa orientale—e sono successivamente spesso esportati come “prodotti Italiani.” Questo processo di globalizzazione del mercato dei funghi spontanei, pur offrendo un significativo introito ai raccoglitori e commercianti rurali su tutto il globo, è responsabile di altri effetti, come per l’appunto una sorta di marchio nazionale “Italiano” su alcuni prodotti di provenienza globale, come per l’appunto i porcini, cosa che contrasta con alcune delle regole dell’Unione Europea in materia di denominazioni regionali.
  相似文献   

10.
Xanthophyceae are a group of heterokontophyte algae. Few molecular studies have investigated the evolutionary history and phylogenetic relationships of this class. We sequenced the nuclear-encoded SSU rDNA and chloroplast-encoded rbcL genes of several xanthophycean species from different orders, families, and genera. Neither SSU rDNA nor rbcL genes show intraspecific sequence variation and are good diagnostic markers for characterization of problematic species. New sequences, combined with those previously available, were used to create different multiple alignments. Analyses included sequences from 26 species of Xanthophyceae plus three Phaeothamniophyceae and two Phaeophyceae taxa used as outgroups. Phylogenetic analyses were performed according to Bayesian inference, maximum likelihood, and maximum parsimony methods. We explored effects produced on the phylogenetic outcomes by both taxon sampling as well as selected genes. Congruent results were obtained from analyses performed on single gene multiple alignments as well as on a data set including both SSU rDNA and rbcL sequences. Trees obtained in this study show that several currently recognized xanthophycean taxa do not form monophyletic groups. The order Mischococcales is paraphyletic, while Tribonematales and Botrydiales are polyphyletic even if evidence for the second order is not conclusive. Botrydiales and Vaucheriales, both including siphonous taxa, do not form a clade. The families Botrydiopsidaceae, Botryochloridaceae, and Pleurochloridaceae as well as the genera Botrydiopsis and Chlorellidium are polyphyletic. The Centritractaceae and the genus Bumilleriopsis also appear to be polyphyletic but their monophyly cannot be completely rejected with current evidence. Our results support morphological convergence at any taxonomic rank in the evolution of the Xanthophyceae. Finally, our phylogenetic analyses exclude an origin of the Xanthophyceae from a Vaucheria-like ancestor and favor a single early origin of the coccoid cell form.  相似文献   

11.
Phylogenetic relationships of mushrooms and their relatives within the order Agaricales were addressed by using nuclear large subunit ribosomal DNA sequences. Approximately 900 bases of the 5' end of the nucleus-encoded large subunit RNA gene were sequenced for 154 selected taxa representing most families within the Agaricales. Several phylogenetic methods were used, including weighted and equally weighted parsimony (MP), maximum likelihood (ML), and distance methods (NJ). The starting tree for branch swapping in the ML analyses was the tree with the highest ML score among previously produced MP and NJ trees. A high degree of consensus was observed between phylogenetic estimates obtained through MP and ML. NJ trees differed according to the distance model that was used; however, all NJ trees still supported most of the same terminal groupings as the MP and ML trees did. NJ trees were always significantly suboptimal when evaluated against the best MP and ML trees, by both parsimony and likelihood tests. Our analyses suggest that weighted MP and ML provide the best estimates of Agaricales phylogeny. Similar support was observed between bootstrapping and jackknifing methods for evaluation of tree robustness. Phylogenetic analyses revealed many groups of agaricoid fungi that are supported by moderate to high bootstrap or jackknife values or are consistent with morphology-based classification schemes. Analyses also support separate placement of the boletes and russules, which are basal to the main core group of gilled mushrooms (the Agaricineae of Singer). Examples of monophyletic groups include the families Amanitaceae, Coprinaceae (excluding Coprinus comatus and subfamily Panaeolideae), Agaricaceae (excluding the Cystodermateae), and Strophariaceae pro parte (Stropharia, Pholiota, and Hypholoma); the mycorrhizal species of Tricholoma (including Leucopaxillus, also mycorrhizal); Mycena and Resinomycena; Termitomyces, Podabrella, and Lyophyllum; and Pleurotus with Hohenbuehelia. Several groups revealed by these data to be nonmonophyletic include the families Tricholomataceae, Cortinariaceae, and Hygrophoraceae and the genera Clitocybe, Omphalina, and Marasmius. This study provides a framework for future systematics studies in the Agaricales and suggestions for analyzing large molecular data sets.  相似文献   

12.
Zhu Q  Ge S 《The New phytologist》2005,167(1):249-265
The A-genome group in Oryza consists of eight diploid species and is distributed world-wide. Here we reconstructed the phylogeny among the A-genome species based on sequences of nuclear genes and MITE (miniature inverted-repeat transposable elements) insertions. Thirty-seven accessions representing two cultivated and six wild species from the A-genome group were sampled. Introns of four nuclear single-copy genes on different chromosomes were sequenced and analysed by both maximum parsimony (MP) and Bayesian inference methods. All the species except for Oryza rufipogon and Oryza nivara formed a monophyletic group and the Australian endemic Oryza meridionalis was the earliest divergent lineage. Two subspecies of Oryza sativa (ssp. indica and ssp. japonica) formed two separate monophyletic groups, suggestive of their polyphyletic origin. Based on molecular clock approach, we estimated that the divergence of the A-genome group occurred c. 2.0 million years ago (mya) while the two subspecies (indica and japonica) separated c. 0.4 mya. Intron sequences of nuclear genes provide sufficient resolution and are informative for phylogenetic inference at lower taxonomic levels.  相似文献   

13.
Yeasts of the artificial genus Candida include plant endophytes, insect symbionts, and opportunistic human pathogens. Phylogenies based on rRNA gene and actin sequences confirmed that the genus is not monophyletic, and the relationships among Candida species and allied teleomorph genera are not clearly resolved. Protein-coding genes have been useful to resolve taxonomic positions among a broad range of fungi. Over 70 taxa of the genus Candida and its allied sexually reproducing genera were therefore selected, and their phylogenetic relationships were investigated using nuclear sequences of the largest subunit and second largest subunit of RNA polymerase II gene, actin, the second subunit of the mitochondrial cytochrome oxidase gene, and D1/D2 LSU rRNA gene. The DNA sequences were analysed by maximum parsimony and Bayesian inference, resulting in the recognition of six major phylogenetic groups (A-F). Group A contains six facultative pathogenic Candida species, which seem to have derived from nonpathogenic species, while Group B contains species of Clavispora, Metschnikowia, and Pichia guilliermondii. Species of Debaryomyces form an independent group C that is related to groups A and B. Pichia fermentans and other environmental species are concentrated in Group D. Group E, containing Pichia anomala, may be a sibling to group F, which is represented by the Saccharomyces species complex.  相似文献   

14.
With ~1000 species distributed pantropically, the genus Piper is one of the most diverse lineages among basal angiosperms. To rigorously address the evolution of Piper we use a phylogenetic analysis of sequences of the internal transcribed spacers (ITS) of nuclear ribosomal DNA based on a worldwide sample. Sequences from a total of 51 species of Piper were aligned to yield 257 phylogenetically informative sites. A single unrooted parsimony network suggested that taxa representing major geographic areas could potentially form three monophyletic groups: Asia, the South Pacific, and the Neotropics. The position of Pothomorphe was well supported among groups of New World taxa. Simultaneous phylogenetic analysis of an expanded alignment including outgroups suggested that taxa from the South Pacific and Asia formed a monophyletic group, provisionally supporting a single origin of dioecy. Within the Neotropical sister clade, resolution was high and strong bootstrap support confirmed the monophyly of several traditionally recognized infrageneric groups (e.g., Enckea [including Arctottonia], Ottonia, Radula, Macrostachys). In contrast, some of the species representing the highly polytypic subgroup Steffensia formed a clade corresponding to the previously recognized taxon Schilleria, while others were strongly associated with several of the more specialized groups of taxa. The distribution of putatively derived inflorescence and floral character states suggested that both umbellate and solitary axillary inflorescences have multiple origins. Reduction in anther number appears to be associated with highly packaged inflorescences or with larger anther primordia per flower, trends that are consistent with the suppression of later stages of androecial development.  相似文献   

15.
The aim of this study was to compare the usefulness of complete small and large subunit rRNA, and a combination of both molecules, for reconstructing stramenopile evolution. To this end, phylogenies from species of which both sequences are known Acre constructed with the neighbor-joining, maximum parsimony, and maximum likelihood methods. Also the use of structural features of the rRNAs was evaluated. The large subunit rRNA from the diatom Skeletonema pseudocostatum was sequenced in order to have a more complete taxon sampling, and a group I intron was identified. Our results indicated that heterokont algae are monophyletic, with diatoms diverging first. However, as the analysis was restricted to a particular data set containing merely six taxa, the outcome has limited value for elucidating stramenopile relationships. On the other hand, this approach permits comparison of the performance of both rRNA molecules without interference from other factors, such as a different species selection for each molecule. For the taxa used, the large subunit rRNA clearly contained more phylogenetic information than the small subunit rRNA. Although this result can definitely not be generalized and depends on the phvlogeny to be studied, in some cases determining complete large subunit rRNA sequences certainly seems worthwhile.  相似文献   

16.
To understand the biogeography of truffle-like fungi, DNA sequences were analysed from representative taxa of Hysterangiales. Multigene phylogenies and the results of ancestral area reconstructions are consistent with the hypothesis of an Australian, or eastern Gondwanan, origin of Hysterangiales with subsequent range expansions to the Northern Hemisphere. However, neither Northern Hemisphere nor Southern Hemisphere taxa formed a monophyletic group, which is in conflict with a strictly vicariant scenario. Therefore, the occurrence and importance of long-distance dispersal could not be rejected. Although a pre-Gondwanan origin of Hysterangiales remains as a possibility, this hypothesis requires that Hysterangiales exist prior to the origin of the currently recognized ectomycorrhizal plants, as well as the arrival of mycophagous animals in Australia. This also requires that a basal paraphyletic assemblage represents parallel evolution of the ectomycorrhizal symbiosis, or that Hysterangiales was mycorrhizal with members of the extinct flora of Gondwana. Regardless, models for both ancient and more recent origins of Hysterangiales are consistent with truffle-like fungi being capable of transoceanic dispersal.  相似文献   

17.
The genera Neurospora and Gelasinospora are conventionally distinguished by differences in ascospore ornamentation, with elevated longitudinal ridges (ribs) separated by depressed grooves (veins) in Neurospora and spherical or oval indentations (pits) in Gelasinospora. The phylogenetic relationships of representatives of 12 Neurospora and 4 Gelasinospora species were assessed with the DNA sequences of four nuclear genes. Within the genus Neurospora, the 5 outbreeding conidiating species form a monophyletic group with N. discreta as the most divergent, and 4 of the homothallic species form a monophyletic group. In combined analysis, each of the conventionally defined Gelasinospora species was more closely related to a Neurospora species than to another Gelasinospora species. Evidently, the Neurospora and Gelasinospora species included in this study do not represent two clearly resolved monophyletic sister genera, but instead represent a polyphyletic group of taxa with close phylogenetic relationships and significant morphological similarities. Ascospore morphology, the character that the distinction between the genera Neurospora and Gelasinospora is based upon,was not an accurate predictor of phylogenetic relationships.  相似文献   

18.
Molecular systematics and biological diversification of Boletales   总被引:2,自引:0,他引:2  
Binder M  Hibbett DS 《Mycologia》2006,98(6):971-981
Historical patterns of morphological evolution and ecology in the Boletales are largely unresolved but appear to involve extensive convergence. We studied phylogenetic relationships of Boletales based on two datasets. The nuc-lsu dataset is broadly sampled and includes roughly 30% of the described species of Boletales and 51 outgroup taxa across the Hymenomycetes. The multigene dataset (nuc-ssu, nuc-lsu, 5.8S, mt-lsu, atp6) sampled 42 key species of Boletales in a framework of 14 representative Hymenomycetes. The Boletales are strongly supported as monophyletic in our analyses on both datasets with parsimony, maximum likelihood and Bayesian approaches. Six major lineages of Boletales that currently are recognized on subordinal level, Boletineae, Paxillineae, Sclerodermatineae, Suillineae, Tapinellineae, Coniophorineae, received varied support. The backbone of the Boletales was moderately resolved in the analyses with the nuc-lsu dataset, but support was strong for most major groups. Nevertheless, most brown-rot producing forms were placed as a paraphyletic grade at the base of the Boletales. Analyses on the multigene dataset confirm sister group relationships among Boletales, Agaricales and Atheliales. Boletineae and Suillineae received the highest support values; Paxillineae and Sclerodermatineae were not consistently resolved as monophyletic groups. The Coniophorineae were not monophyletic in any analyses. The Tapinellineae consisting of morphologically diverse brown-rotting fungi forms the basal group in the Boletales. We performed ancestral state reconstruction with BayesMultiState, which suggested that the ancestor of the Boletales was a resupinate or polyporoid saprotrophic fungus, producing a brown-rot.  相似文献   

19.
One hundred and seventeen clades of euagarics   总被引:23,自引:0,他引:23  
This study provides a first broad systematic treatment of the euagarics as they have recently emerged in phylogenetic systematics. The sample consists of 877 homobasidiomycete taxa and includes approximately one tenth (ca. 700 species) of the known number of species of gilled mushrooms that were traditionally classified in the order Agaricales. About 1000 nucleotide sequences at the 5(') end of the nuclear large ribosomal subunit gene (nLSU) were produced for each taxon. Phylogenetic analyses of nucleotide sequence data employed unequally weighted parsimony and bootstrap methods. Clades revealed by the analyses support the recognition of eight major groups of homobasidiomycetes that cut across traditional lines of classification, in agreement with other recent phylogenetic studies. Gilled fungi comprise the majority of species in the euagarics clade. However, the recognition of a monophyletic euagarics results in the exclusion from the clade of several groups of gilled fungi that have been traditionally classified in the Agaricales and necessitates the inclusion of several clavaroid, poroid, secotioid, gasteroid, and reduced forms that were traditionally classified in other basidiomycete orders. A total of 117 monophyletic groups (clades) of euagarics can be recognized on the basis on nLSU phylogeny. Though many clades correspond to traditional taxonomic groups, many do not. Newly discovered phylogenetic affinities include for instance relationships of the true puffballs (Lycoperdales) with Agaricaceae, of Panellus and the poroid fungi Dictyopanus and Favolaschia with Mycena, and of the reduced fungus Caripia with Gymnopus. Several clades are best supported by ecological, biochemical, or trophic habits rather than by morphological similarities.  相似文献   

20.
Boletus roseoflavus is described as a new species based on morphological and molecular studies of the type collection and additional materials. Boletus roseoflavus is morphologically distinct from other related species (B. regius, B. appendiculatus, and B. speciosus) by its light pink, pink, or rosy pileus, lemon yellow or golden yellow context, and lemon yellow or light yellow, enlarged download stipe with yellow reticulation. Phylogenetic analyses based on ribosomal DNA internal transcribed spacer regions and nuclear large subunit ribosomal RNA indicate that B. roseoflavus belongs to Boletus section Appendiculati.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号