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1.
The order Ceraceosorales (Ustilaginomycotina) currently includes the single genus Ceraceosorus, with one species, Ceraceosorus bombacis, parasitic on Bombax ceiba in India. The diversity, biogeography, evolution, and phylogenetic relationships of this order are still relatively unknown. Here, a second species of Ceraceosorus is described from West Africa as a novel species, Ceraceosorus africanus, infecting Bombax costatum in Benin, Ghana, and Togo. This species produces conspicuous fructifications, similar to corticioid basidiomata when mature, but sorus-like in early stages of ontogenetic development. The fructifications cover much of the leaf surface and resemble leaf blight. This contrasts with the inconspicuous fructifications of C. bombacis comprising small spots scattered over the lower leaf surface that resemble leaf spot. Both species of Ceraceosorus differ in several micromorphological traits, infect different host plant species in widely separated geographical areas, and are separated by a considerable genetic distance in 28S rDNA and RPB2 genes. The distinct corticioid fructification of C. africanus is a unique morphological trait within the Ustilaginomycotina. Molecular phylogenetic analyses of a single gene dataset (D1/D2 28S rDNA) supported the monophyly of the two Ceraceosorus species and the Ceraceosorales and their placement within the Ustilaginomycotina. Molecular phylogenetic analyses of a multigene dataset (18S/5.8S/28S rDNA/RPB2/TEF1) revealed Exobasidium rhododendri (Exobasidiales) as the closest relative of Ceraceosorus, both clustering together with Entyloma calendulae (Entylomatales), indicating affinities to the Exobasidiomycetes. This phylogenetic placement is in agreement with ultrastructural characteristics (presence of local interaction zone and interaction apparatus) reported for the Ceraceosorales, Entylomatales, and Exobasidiales.  相似文献   

2.
The simple-septate basidiomycetes: a synopsis   总被引:1,自引:1,他引:0  
The simple-septate basidiomycetes comprise more than 8,000 species that show a high morphological and ecological heterogeneity. To gain insight in the phylogenetic relationships within this group, we compared several ultrastructural features such as septal pore apparatus, form, and behavior of the spindle pole bodies, types of host–parasite interaction, presence or absence of colacosomes, symplechosomes, atractosomes, and cystosomes as well as nuclear rDNA sequences coding for small- and large-subunit rRNA. Based on our integrated analysis, we propose a new classification system for the simple-septate basidiomycetes with the subphylum Pucciniomycotina and the classes Agaricostilbomycetes, Atractiellomycetes, Classiculomycetes, Cryptomycocolacomycetes, Cystobasidiomycetes, Microbotryomycetes, Mixiomycetes, and Pucciniomycetes. We also propose the pucciniomycotinous taxa Cystobasidiales, Erythrobasidiales, Helicobasidiales, Mixiales, Naohideales, Pachnocybales, Spiculogloeales, and Kondoaceae and the new subphyla Agaricomycotina (equivalent to the current Hymenomycetes) and Ustilaginomycotina (equivalent to the current Ustilaginomycetes).  相似文献   

3.
The evolutionary history, divergence times and phylogenetic relationships of Uleiella chilensis (Ustilaginomycotina, smut fungi) associated with Araucaria araucana were analysed. DNA sequences from multiple gene regions and morphology were analysed and compared to other members of the Basidiomycota to determine the phylogenetic placement of smut fungi on gymnosperms. Divergence time estimates indicate that the majority of smut fungal orders diversified during the Triassic–Jurassic period. However, the origin and relationships of several orders remain uncertain. The most recent common ancestor between Uleiella chilensis and Violaceomyces palustris has been dated to the Lower Cretaceous. Comparisons of divergence time estimates between smut fungi and host plants lead to the hypothesis that the early Ustilaginomycotina had a saprobic lifestyle. As there are only two extant species of Araucaria in South America, each hosting a unique Uleiella species, we suggest that either coevolution or a host shift followed by allopatric speciation are the most likely explanations for the current geographic restriction of Uleiella and its low diversity. Phylogenetic and age estimation analyses, ecology, the unusual life-cycle and the peculiar combination of septal and haustorial characteristics support Uleiella chilensis as a distinct lineage among the Ustilaginomycotina. Here, we describe a new ustilaginomycetous order, the Uleiellales to accommodate Uleiella. Within the Ustilaginomycetes, Uleiellales are sister taxon to the Violaceomycetales.  相似文献   

4.
Two fungal-like organisms (class Oomycetes) and 263 species of fungi from 111 genera, 42 families, 23 orders, and 7 classes have been found on the territory of Aksu-Zhabagly Nature Reserve. Twenty-two species are found for the first time. The vast majority of species are parasitic (202 species), 56 species belong to saprotrophs, and 7 to symbiotrophs. Classes Taphrinomycetes, Urediniomycetes, and Ustilaginomycetes are represented exclusively by parasites. There have been found 21 saprotrophic, 27 parasitic, and 4 symbiotrophic species in the class Ascomycetes. The most numerous group in the class Basidiomycetes is the group of humus saprotrophs; it contains 15 species. Groups of litter saprotrophs and parasites contain four species each, symbiotrophic species have three species, coprotrophs and xylotrophs have two species each, and litter and humus saprotrophs have one species each. Anamorphic fungi are represented by 91 parasitic and 11 saprotrophic species. In comparison with closely located Sairam-Ugam National Park and the Karatau Nature Reserve, the mycobiota of Aksu-Zhabagly is characterized by a significant number of species in the classes Basidiomycetes, Urediniomycetes, Hyphomycetes, and Coelomycetes. Thirty-one species are common to these protected areas. The most numerous group is parasites.  相似文献   

5.
格氏梅拉菌Meira geulakonigii最早是在柑桔锈螨病的枯枝中发现的,它是一种担子菌类酵母样无性态真菌,归属于黑粉菌纲外担子菌亚纲。目前仅了解这种真菌在植物中的生长状态,关于它的宿主范围、区域分布和生长特性依然知之甚少。首次从竹子中分离了两株新的Meira geulakonigii菌株(PM1和PM2),并且更深一步地描述了他们的生理特性,尤其着重表述了菌丝体的独特生长现象。与先前报导的两株M.geulakonigii菌株PFS004和AS004相比较,PM1和PM2在分子系统上与AS004更相近,而生理现象与PFS004更相似。这两株菌株的成功分离可能有助于毛竹中Meira真菌菌丝体形成和功能的进一步研究。  相似文献   

6.
The genus Meira currently contains three recently described species of mite-associated basidiomycete yeasts from Israel and Japan and is placed in the Exobasidiomycetes (Ustilaginomycotina) Incertae sedis. A previously undescribed species of Meira was isolated from the phylloplane of a magnolia leaf in Louisiana, USA. Herein, we describe Meira miltonrushii sp. nov. and include phylogenetic analyses from three rDNA loci to resolve the placement of Meira. This study provides evidence that Meira belongs to the family Brachybasidiaceae in the Exobasidiales and supports the placement of another mite-associated yeast genus, Acaromyces, within Cryptobasidiaceae (Exobasidiales). We also examine sequences produced by numerous environmental studies that suggest Meira species can be found as endophytes of many plant species. To our knowledge, this is the first record of a member of the genus Meira in North America.  相似文献   

7.
A group of holobasidiate mycoparasites, growing on Basidiomycetes, was studied by light– and electron microscopy. The parasites develop haustoria which penetrate the host–cells. Often a hypertrophic, gall–like growth of the host is induced by this parasitic interaction. Ana– and teleomorph stages and functions are highly diverse and not yet fully understood. Two species produce unique zygoconidia. The mechanism of spore abstriction on apically sterigmate holobasidia is hymenomycet–ous or gasteromycetous, and the basidiospores usually germinate by budding. Doli–pores without parenthesomes were found in three species. A heterobasidiomycetous relationship is proposed for the three genera, Christiansenia, Syzygospora , and Car–cinomyces gen. nov. Taxonomic considerations led to the proposal of a new family, the Carcinomycetaceae.
This is Part 11 of a series, "Studies in Heterobasidiomycetes" of the Institut für Biologie I, Lehrstuhl Spezielle Botanik, Universitat Tubingen and the Department of Botany, University of British Columbia.  相似文献   

8.
The systematic position of two strains of a yeast-like fungus isolated from plant remnants on the Kharg Island in the Persian Gulf of Iran is evaluated using morphological, physiological and phylogenetic analyses. In culture, this fungus produced cylindrical cells that reproduced by polar budding on short stalks. Production of ballistoconidia and blastospores was observed. The carbon source assimilation spectrum was broad, but fermentation ability was absent. Phylogenetic analyses of the nuclear SSU, LSU (D1/D2 domain), and ITS rDNA revealed that this fungus represents a new lineage in the Urocystidales of the subphylum Ustilaginomycotina. Based on the comparison of phenotypic characters, physiology, and DNA sequences, a new genus and species Fereydounia khargensis (IBRC-M 30116T?=?CBS 13305T) is described for this fungus and accommodated in the novel family Fereydouniaceae. This is the first report of anamorphic saprobic fungus residing in the Urocystidales, stressing the remarkable evolutionary diversity in the subphylum Ustilaginomycotina.  相似文献   

9.
Environmental sampling yielded two yeast species belonging to Microstromatales (Exobasidiomycetes, Ustilaginomycotina). The first species was collected from a leaf phylloplane infected by the rust fungus Coleosporium plumeriae, and represents a new species in the genus Jaminaea, for which the name Jaminaea rosea sp. nov. is proposed. The second species was isolated from air on 50% glucose media and is most similar to Microstroma phylloplanum. However, our phylogenetic analyses reveal that species currently placed in Microstroma are not monophyletic, and M. phylloplanum, M. juglandis and M. albiziae are not related to the type species of this genus, M. album. Thus, Pseudomicrostroma gen. nov. is proposed to accommodate the following species: P. glucosiphilum sp. nov., P. phylloplanum comb. nov. and P. juglandis comb. nov. We also propose Parajaminaea gen. nov. to accommodate P. albizii comb. nov. and P. phylloscopi sp. nov. based on phylogenetic analyses that show these are not congeneric with Jaminaea or Microstroma. In addition, we validate the genus Jaminaea, its respective species and two species of Sympodiomycopsis and provide a new combination, Microstroma bacarum comb. nov., for the anamorphic yeast Rhodotorula bacarum. Our results illustrate non-monophyly of Quambalariaceae and Microstromataceae as currently circumscribed. Taxonomy of Microstroma and the Microstromataceae is reviewed and discussed. Finally, analyses of all available small subunit rDNA sequences for Jaminaea species show that J. angkorensis is the only known species that possess a group I intron in this locus, once considered a potential feature indicating the basal placement of this genus in Microstromatales.  相似文献   

10.
Põldmaa K 《Mycologia》2003,95(5):921-933
Of the eight species of Hypomyces that occur on basidiomata of Stereum species, only H. sympodiophorus grows exclusively on members of this genus. Morphologically similar fungi were found on species of Xylobolus, a genus closely related to Stereum. These are described as two new species of Hypomyces: H. thailandicus, collected on Xylobolus cf. illudens in Thailand; and H. xyloboli, on X. frustulatus and X. subpileatus in the eastern United States. These three species are unusual in Hypomyces because of their almost indistinguishable anamorphs. In parsimony analysis of LSU nuclear rDNA sequences, the three species growing only on Stereaceae do not form a monophyletic group but their constrained monophyly is not rejected either. A morphologically similar anamorphic species, Sibirina gamsii, included in the study, is transferred to the genus Cladobotryum.  相似文献   

11.
Pollen and orbicule morphology of 84 species, representing 52 genera from all tribes and subfamilies are investigated, in order to assess the systematic value of palynological data and to determine palynological evolutionary trends in Cyperaceae. A total of 90% of the species are examined for the first time with scanning electron microscopy. Pollen grains of Cyperaceae are oblate spheroidal to perprolate in shape, inaperturate to polyporate with opercula or pontopercula on pori or colpi. We distinguished seven different sexine ornamentation patterns. Orbicules occur in all species investigated. Pollen morphological variation within Cyperaceae is considerable and includes dispersal unit; number, location and degree of differentiation of apertural zones; and sexine ornamentation patterns. In subfamily Mapanioideae both tribes can be characterized by palynological synapomorphies. However, in subfamily Cyperoideae, the observed pattern of variation does not fit the most recent molecular phylogeny due to high levels of homoplasy and polymorphism in major pollen characters.  相似文献   

12.
Relationships among species assigned to the ascosporic yeast genera Sporopachydermia, Stephanoascus, Trichomonascus, Wickerhamiella and Zygoascus, and to the associated anamorphic genera Arxula, Blastobotrys, Sympodiomyces and Trigonopsis, were determined from phylogenetic analyses of gene sequences from the nearly complete large-subunit rRNA gene, the mitochondrial small-subunit rRNA gene, and cytochrome oxidase II. The genus Stephanoascus is polyphyletic, resulting in reassignment of two species to the older genus Trichomonascus and the third to Sugiyamaella gen. nov. (type species Sugiyamaella smithiae). The genera Sporopachydermia, Wickerhamiella and Zygoascus appear to be monophyletic. The species Pichia ofunaensis and P. tannicola are proposed for transfer to Zygoascus. Arxula, Blastobotrys and Sympodiomyces are members of the Trichomonascus clade, with the genus Blastobotrys having taxonomic priority for anamorphic states. Trigonopsis variabilis and three species of Candida represent a distinct clade. From the foregoing gene sequence analyses, the new ascosporic genus Sugiyamaella is proposed, as are 14 new species combinations and the new family Trichomonascaceae.  相似文献   

13.
The results of longstanding studies of yeasts inhabiting soil, plant surface, and plant residues in typical subboreal forests of the European part of Russia are summarized. The abundance and species diversity of yeast communities in the array of substrates corresponding to succession stages in plant residues decomposition are shown to steadily decline. Each stage is characterized by its specific set of dominating species. The yeast diversity in forest biogeocenoses is shown to surpass that in other geographic zones. This manifests itself in a greater number of species occurring in similar arrays of substrates, in the absence of conspicuous dominants on the biogeocenotic level, and in a higher differentiation of the yeast population with respect to its habitat type. The forest yeast populations are also characterized by high diversity of yeasts of ascomycetous affinity and of the anamorphic stages of Taphrinales and Tremellales, as well as by the presence of typical pedobiont species (except Lipomyces spp.).  相似文献   

14.
Summary The structure and development of the complex periplast, or cell covering, of cryptomonads is reviewed. The periplast consists of the plasma membrane (PM) plus an associated surface periplast component (SPC) and cytoplasmic or inner periplast component (IPC). The structure of the SPC and IPC, and their association with the PM, varies considerably between genera. This review, which concentrates on cryptomonads with an IPC of discrete plates, discusses relationships between periplast components and examines the development of this unique cell covering. Formation and growth of inner plates occurs throughout the cell cycle from specialized regions termed anamorphic zones. Crystalline surface plates, which comprise the SPC in many cryptomonad species, appear to form by self-assembly of disorganized subunits. InKomma caudata the subunits are composed of a high molecular weight glycoprotein that is produced within the endomembrane system and deposited onto the cell surface within anamorphic zones. The self-assembly of subunits into highly ordered surface plates appears closely associated with developmental changes in the underlying IPC and PM.  相似文献   

15.
16.
Malassezia is a unique lipophilic genus in class Malasseziomycetes in Ustilaginomycotina, (Basidiomycota, fungi) that otherwise consists almost exclusively of plant pathogens. Malassezia are typically isolated from warm-blooded animals, are dominant members of the human skin mycobiome and are associated with common skin disorders. To characterize the genetic basis of the unique phenotypes of Malassezia spp., we sequenced the genomes of all 14 accepted species and used comparative genomics against a broad panel of fungal genomes to comprehensively identify distinct features that define the Malassezia gene repertoire: gene gain and loss; selection signatures; and lineage-specific gene family expansions. Our analysis revealed key gene gain events (64) with a single gene conserved across all Malassezia but absent in all other sequenced Basidiomycota. These likely horizontally transferred genes provide intriguing gain-of-function events and prime candidates to explain the emergence of Malassezia. A larger set of genes (741) were lost, with enrichment for glycosyl hydrolases and carbohydrate metabolism, concordant with adaptation to skin’s carbohydrate-deficient environment. Gene family analysis revealed extensive turnover and underlined the importance of secretory lipases, phospholipases, aspartyl proteases, and other peptidases. Combining genomic analysis with a re-evaluation of culture characteristics, we establish the likely lipid-dependence of all Malassezia. Our phylogenetic analysis sheds new light on the relationship between Malassezia and other members of Ustilaginomycotina, as well as phylogenetic lineages within the genus. Overall, our study provides a unique genomic resource for understanding Malassezia niche-specificity and potential virulence, as well as their abundance and distribution in the environment and on human skin.  相似文献   

17.
A leaf survey of 59 tropical (43 African, and 16 South American) Cyperaceae showed that in addition to the expected flavonoid constituents, i.e. glycoflavones and tricin derivatives, a representative number of them (33%) contained luteolin 5-methyl ether. An equal sample of temperate Cyperaceae failed to show any species with this substance. Thus it appears that this rare 5-methylated flavone is restricted to tropical members of the family. In four species of the South American genus, Lagenocarpus, 6-hydroxyluteolin 7-glucoside was identified. This is the first report of this 6-hydroxyflavone in the Cyperaceae and in the monocotyledons. A new glycoside of iso-orientin, the 3'-glucuronide, was identified in Rhynchospora eximia. The new data have been collected in a revised summary of the leaf flavonoid pattern of the Cyperaceae and compared with those of the Gramineae and Juncaceae. The discovery of luteolin 5-methyl ether in the Cyperaceae brings it closer in chemical terms to the Juncaceae, from which family this compound was first isolated  相似文献   

18.
Vascular epiphytes are widespread throughout the tropics where they are usually not restricted to particular phorophytes. In contrast to this the trunks of arborescent Cyperaceae and Velloziaceae are regularly colonised by vascular epiphytes with certain orchids showing a remarkably high degree of phorophyte specificity. Arborescent, desiccation-tolerant Cyperaceae (e.g. Afrotrilepis) and Velloziaceae (e.g. Vellozia, Xerophyta) form characteristic elements of rock outcrop vegetation in the Neotropics and Paleotropics where they frequently occur with mat-forming species. Their woody-fibrous stems mainly consist of persistent leaf bases and adventitious roots which possess a velamen radicum. In tropical Africa several species of Polystachya occur in mats and on stems of Cyperaceae (e.g. P. microbambusa on Afrotrilepis pilosa) and Velloziaceae (e.g. P. johnstonii on Xerophyta splendens). In Brazil a higher number of orchid species (e.g. Constantia cipoensis, Pseudolaelia vellozicola, Sophronites brevipedunculata) are largely restricted to the stems of Velloziaceae growing on rock outcrops. Moreover, in Brazil a number of non-phorophyte specific orchids (e.g. Epidendrum saxatile, Prosthechea vespa) grow on the trunks of Velloziaceae. Orchids restricted to the stems of Cyperaceae and Velloziaceae were derived from non-phorophyte specific, epiphytic/lithophytic ancestors and originated independently in South America and Africa. The exact nature of the relationship between arborescent Cyperaceae and Velloziaceae and epiphytic orchids growing exclusively on their trunks is not yet clear. In a number of areas both the highly host specific orchids and the arborescent Cyperaceae/Velloziaceae are seriously threatened by human lit fires and commercial collection.  相似文献   

19.
The Ustilaginomycotina, often collectively referred to as smut fungi, represent one of the three subphyla of the Basidiomycota. Smut fungi predominantly parasitize Angiosperms, are globally distributed, and contain several economically important pathogens. The most species-rich family of the smut fungi is the Ustilaginaceae. To investigate the molecular phylogeny of smut fungi, most studies rely on nrDNA loci, such as ITS and LSU. Protein coding genes, like rpb1, rpb2, TeF1a, atp6, and ß-tubulin, have been used in some studies. However, because of the huge diversity of smut fungi and the lack of dedicated primers, amplification of these loci has proven difficult for several groups. Thus, it was the aim of the current study to develop primers for new loci for the smut fungi with the focus on the largest family, the Ustilaginaceae. Here, the development and testing of new primers for nine loci based on protein-coding genes is reported (myosin, map, rpl3, tif2, ssc1, ß-tubulin, sdh1, rpl4A and atp2). A list of various primer combinations for the amplification of the new loci is given, with the corresponding PCR conditions and the best combinations for several genera of the Ustilaginaceae and some other Ustilaginomycetes. We hope that the primers presented in this study will be useful in overcoming the limitations of currently-used loci in terms of phylogenetic resolution, especially with respect to resolving species complexes and providing a better resolution of the higher-level phylogenetic relationships of smut fungi.  相似文献   

20.
A fundamental question in biology is how diversity evolves and why some clades are more diverse than others. Phenotypic diversity has often been shown to result from morphological adaptation to different habitats. The role of behavioral interactions as a driver of broadscale phenotypic diversity has received comparatively less attention. Behavioral interactions, however, are a key agent of natural selection. Antagonistic behavioral interactions with predators or with parasites can have significant fitness consequences, and hence act as strong evolutionary forces on the phenotype of species, ultimately generating diversity between species of both victims and exploiters. Avian obligate brood parasites lay their eggs in the nests of other species, their hosts, and this behavioral interaction between hosts and parasites is often considered one of the best examples of coevolution in the natural world. In this review, we use the coevolution between brood parasites and their hosts to illustrate the potential of behavioral interactions to drive evolution of phenotypic diversity at different taxonomic scales. We provide a bridge between behavioral ecology and macroevolution by describing how this interaction has increased avian phenotypic diversity not only in the brood parasitic clades but also in their hosts.  相似文献   

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