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A new genus, Tectobasidium, is described to accommodate T. chlamydosporum, comb. nov. (= Achroomyces chlamydosporus), and T. cornutum, sp. nov. Both species possess two-celled basidia and cylindrical basidiospores, as well as characteristic, thick-walled and cyanophilous chlamydospores. Tectobasidium spp. develop in the living basidiocarps of other basidiomycetes (Helicogloea and Myxarium) as intrahymenial fungi. No signs of the parasitic habit have been detected for them, although a mycoparasitic strategy cannot be completely ruled out. nc LSU rDNA-based phylogenetic inference places Tectobasidium at the very base of the subphylum Ustilaginomycotina, with moderate (BI) or strong (ML) support. Due to the lack of additional DNA, ultrastructural, and cultural data, we leave the suprageneric classification of Tectobasidium unresolved. [ABSTRACT FROM AUTHOR]

The mycorrhizal fungi of cultivated Vanilla spp. have mainly been studied in America, while a recent study has investigated them on Réunion Island (Indian Ocean). However, there are many different types of cultivation on Réunion, from shade-house crops to forest farms of endemic or exotic trees. Here we fill a gap in the study of the root mycobiome of Vanilla by sampling vines in forest plantations on recent lava flows in the southeast of Réunion. Specifically, we aimed to characterize the fungal communities between terrestrial and epiphytic roots, between forest farms that differ mainly in the species of trees, and between Vanilla roots and ECM-like roots of nearby trees. By sequencing fungal ITS2, we showed that the Vanilla root mycobiome is diverse and differed between the root types and forest farms. Epiphytic and terrestrial roots host endophytic fungi, while a putative rust with visible urediniospores was abundant in terrestrial roots mainly. Other pathogens were detected in epiphytic roots (Colletotrichum) with no sign of disease. Following sequencing and electron microscopy, Tulasnellaceae, characterized by imperforate parenthesomes and cell wall expansion with an amorphous matrix, were shown to be the main mycorrhizal fungi in both vanilla root types. Interestingly, the dominant Tulasnellaceae OTU was found in ECM-type roots of trees belonging to the ectomycorrhizal family Sapotaceae. Further observations are needed to confirm the ectomycorrhizal association of endemic trees with Tulasnella. Moreover, labeling experiments will be instrumental in investigating the transfer of nutrients between the trees and the Vanilla through the network of mycorrhizal associations in the soil. [ABSTRACT FROM AUTHOR]

Mycoparasites in Basidiomycota comprise a diverse group of fungi, both morphologically and phylogenetically. They interact with their hosts through either fusion-interaction or colacosome-interaction. Colacosomes are subcellular structures formed by the mycoparasite at the host-parasite interface, which penetrate the parasite and host cell walls. Previously, these structures were detected in 19 fungal species, usually by means of transmission electron microscopy. Most colacosome-forming species have been assigned to Microbotryomycetes (Pucciniomycotina, Basidiomycota), a highly diverse class, comprising saprobic yeasts, mycoparasites, and phytoparasites. In general, these myco- and phytoparasites are dimorphic organisms, with a parasitic filamentous morph and saprobic yeast morph. We investigated colacosome-forming mycoparasites based on fungarium material, freshly collected specimens, and cultures of yeast morphs. We characterised the micromorphology of filamentous morphs, the physiological characteristics of yeast morphs, and inferred phylogenetic relationships based on DNA sequence data from seven loci. We outline and employ an epifluorescence-based microscopic method to assess the presence and organisation of colacosomes. We describe five new species in the genus Colacogloea, the novel dimorphic mycoparasite Mycogloiocolax gerardii, and provide the first report of a sexual, mycoparasitic morph in Colacogloea philyla and in the genus Slooffia. We detected colacosomes in eight fungal species, which brings the total number of known colacosome-forming fungi to 27. Finally, we revealed three distinct types of colacosome organisation in Microbotryomycetes. [ABSTRACT FROM AUTHOR]

Puccinia, which comprises 4000 species, is the largest genus of rust fungi and one of the destructive plant pathogenic rust genera that are reported to infect both agricultural and nonagricultural plants with severe illnesses. The presence of bi-celled teliospores is one of the major features of these rust fungi that differentiated them from Uromyces, which is another largest genus of rust fungi. In the present study, an overview of the current knowledge on the general taxonomy and ecology of the rust genus Puccinia is presented. The status of the molecular identification of this genus along with updated species numbers and their current statuses in the 21st century are also presented, in addition to their threats to both agricultural and nonagricultural plants. Furthermore, a phylogenetic analysis based on ITS and LSU DNA sequence data available in GenBank and the published literature was performed to examine the intergeneric relationships of Puccinia. The obtained results revealed the worldwide distribution of Puccinia. Compared with other nations, a reasonable increase in research publications over the current century was demonstrated in Asian countries. The plant families Asteraceae and Poaceae were observed as the most infected in the 21st century. The phylogenetic studies of the LSU and ITS sequence data revealed the polyphyletic nature of Puccinia. In addition, the presences of too short, too lengthy, and incomplete sequences in the NCBI database demonstrate the need for extensive DNA-based analyses for a better understanding of the taxonomic placement of Puccinia. [ABSTRACT FROM AUTHOR]

Leucosporidium egoroviorum f.a., sp. nov., a new anamorphic species of the basidiomycetous yeasts, was isolated as an endophyte from the fruits of Cucurbita pepo subsp. pepo (zucchini). According to its genetic, physiological, and morphological characteristics, the new species differed significantly from the closely related species L. fellii, L. intermedium, and L. krtinense. The holotype of the new species, KBP Y-6804T, is preserved in a metabolically inactive state; its isotype strains are VKM Y-3065, DSM 113574, and CBS 17590. The MycoBank number is MB 842805. [ABSTRACT FROM AUTHOR]

The type strain Rhodotorula pinalis VKM Y-2963 has been characterized genetically and phylogenetically. The rDNA sequences obtained for the ITS region and D1/D2 domains of LSU have been deposited to NCBI GenBank (OM666053). Strains from the Moscow region, Fellozyma sp. KBP 3851 from Sphagnum mosses and Rh. pinalis VKM Y-2963 from dead conifer needles, were found to be conspecific. The results of phylogenetic analysis suggested that the species Rh. pinalis should be reassigned to the genus Fellozyma. The new combination, Fellozyma pinalis comb. nov., is proposed, MycoBank MB842988. [ABSTRACT FROM AUTHOR]

Uromyces is the second-largest plant pathogenic rust genus, is responsible for numerous diseases, and has major effects on both agricultural and non-agricultural plants. The genus is generally characterized by its unicellular teliospores that help to characterize it and distinguish it from another important rust genus, Puccinia. In this study, a global overview of the diversity and distribution of Uromyces is presented based on both online and offline resources. The information obtained was analyzed for numerical and graphical summaries to provide the diversity and distribution of the genus by country and continent. Besides this, broad taxonomical aspects, a brief life cycle, and other comparative aspects on diversity and distribution were also provided. In addition, a phylogenetic analysis based on the ITS and nLSU DNA sequence data available in GenBank and published literature was performed to examine the intergeneric relationships of Uromyces. The results obtained revealed that the rust genus is found distributed over 150 countries, territories, and occupancies of the world on around 647 plant genera belonging to 95 plant families. Phylogenetic studies based on LSU and ITS sequence data revealed that Uromyces species are polyphyletic and require more DNA-based analyses for a better understanding of their taxonomic placement. [ABSTRACT FROM AUTHOR]

Plants play important roles as habitat and food for a tremendous diversity of specialist animals and fungi. The disappearance of any plant species can lead to extinction cascades of its associated biota. In consequence, documenting the diversity and specificity of plant‐associated organisms is of high practical relevance in biodiversity conservation. Here, we present the first large‐scale molecular investigation into the diversity, host specificity, and cophylogenetic congruence of an especially rich plant–fungal association, the rust fungi (Pucciniaceae) of Cyperaceae and Juncaceae. Using the largest rust fungi DNA barcoding dataset published to date (252 sequences, 82 taxa), we reject the presence of a global ITS2‐28S barcode gap, but find a local gap in Cyperaceae–Juncaceae rusts, and suggest the existence of many cryptic species in North America, with some broadly circumscribed species possibly corresponding to >10 cryptic species. We test previous hypotheses of correlations between the phylogenies of rust fungi and their Cyperaceae–Juncaceae hosts using a combination of global‐fit and event‐based cophylogenetic methods. A significant cophylogenetic signal is detected between rusts and their hosts, but the small number of cospeciations argues for preferential host jumps as the driving process behind these correlations. In addition, temporal congruence between the origin of major Carex clades and their rusts suggests that host diversification may have promoted parasite diversification. Finally, we discuss the relevance of rust infection patterns to the systematics of Cyperaceae, highlight some taxonomic problems uncovered by the analyses, and call attention to the promise of DNA barcoding for bridging knowledge gaps in poorly studied plant‐associated microorganisms. [ABSTRACT FROM AUTHOR]

Austropuccinia psidii, originating in South America, is a globally invasive fungal plant pathogen that causes rust disease on Myrtaceae. Several biotypes are recognized, with the most widely distributed pandemic biotype spreading throughout the Asia-Pacific and Oceania regions over the last decade. Austropuccinia psidii has a broad host range with more than 480 myrtaceous species. Since first detected in Australia in 2010, the pathogen has caused the near extinction of at least three species and negatively affected commercial production of several Myrtaceae. To enable molecular and evolutionary studies into A. psidii pathogenicity, we assembled a highly contiguous genome for the pandemic biotype. With an estimated haploid genome size of just over 1Gb (gigabases), it is the largest assembled fungal genome to date. The genome has undergone massive expansion via distinct transposable element (TE) bursts. Over 90% of the genome is covered by TEs predominantly belonging to the Gypsy superfamily. These TE bursts have likely been followed by deamination events of methylated cytosines to silence the repetitive elements. This in turn led to the depletion of CpG sites in TEs and a very low overall GC content of 33.8%. Compared to other Pucciniales, the intergenic distances are increased by an order of magnitude indicating a general insertion of TEs between genes. Overall, we show how TEs shaped the genome evolution of A. psidii and provide a greatly needed resource for strategic approaches to combat disease spread. [ABSTRACT FROM AUTHOR]

Kuehneola japonica and K. warburgiana are the only species of genus Kuehneola that parasitize plants belonging to genus Rosa (Rosaceae). Systematic revision of the genus Phragmidium and related genera by molecular phylogenetic analyses using nuc rDNA internal transcribed spacer (5.8S-ITS2 = ITS2) and nuc rDNA 28S (28S) sequences indicated that K. japonica and K. warburgiana belong to a group of Phragmidium species that also occur on Rosa. Morphological and molecular phylogenetic analyses revealed that these Kuehneola species were transferred to Phragmidium and renamed as P. japonicum and P. warburgianum. Two new Phragmidium species were also discovered on Rosa from China that could be distinguished from other species in the genus based on aeciospore or urediniospore morphology and phylogenetic placement. The first species, P. jiangxiense, is characterized by a urediniospore surface structure with stout spines that are basally embedded in the wrinkled spore wall. The second species, P. leucoaecium, is characterized by an aeciospore surface structure with irregularly elongated verrucae. Taxonomic descriptions and illustrations are provided. [ABSTRACT FROM AUTHOR]

Abstract Background Rhodotorula toruloides is an outstanding producer of lipids and carotenoids. Currently, information on the key metabolic pathways and their molecular basis of regulation remains scarce, severely limiting efforts to engineer it as an industrial host. Results We have adapted Agrobacterium tumefaciens-mediated transformation (ATMT) as a gene-tagging tool for the identification of novel genes in R. toruloides. Multiple factors affecting transformation efficiency in several species in the Pucciniomycotina subphylum were optimized. The Agrobacterium transfer DNA (T-DNA) showed predominantly single-copy chromosomal integrations in R. toruloides, which were trackable by high efficiency thermal asymmetric interlaced PCR (hiTAIL-PCR). To demonstrate the application of random T-DNA insertions for strain improvement and gene hunting, 3 T-DNA insertional libraries were screened against cerulenin, nile red and tetrazolium violet respectively, resulting in the identification of 22 mutants with obvious phenotypes in fatty acid or lipid metabolism. Similarly, 5 carotenoid biosynthetic mutants were obtained through visual screening of the transformants. To further validate the gene tagging strategy, one of the carotenoid production mutants, RAM5, was analyzed in detail. The mutant had a T-DNA inserted at the putative phytoene desaturase gene CAR1. Deletion of CAR1 by homologous recombination led to a phenotype similar to RAM5 and it could be genetically complemented by re-introduction of the wild-type CAR1 genome sequence. Conclusions T-DNA insertional mutagenesis is an efficient forward genetic tool for gene discovery in R. toruloides and related oleaginous yeast species. It is also valuable for metabolic engineering in these hosts. Further analysis of the 27 mutants identified in this study should augment our knowledge of the lipid and carotenoid biosynthesis, which may be exploited for oil and isoprenoid metabolic engineering.

The genus Bannoa consists of four described species associated with dead leaves in southwestern Japan. In this study, we describe three new species, Bannoa guamensis, B. rosea, and B. tropicalis, from the South Pacific island of Guam and Guyana in South America. Isolates were obtained from surfaces of diseased and healthy leaves of plants in the Euphorbiaceae, Asteraceae, and Poaceae. DNA sequences from four gene regions, including nuc rDNA internal transcribed spacer ITS1‐5.8S‐ITS2 (ITS), D1–D2 domains of nuc 28S rDNA (28S), nuc 18S rDNA (18S), and a portion of tef1, which encodes translation elongation factor 1-alpha, were produced for phylogenetic analysis. Intercompatibility tests were performed, and subsequent development of clamp connections and basidia were documented for B. tropicalis. Potential life history strategies and association with diseased leaves, including rust-infected leaves, were evaluated across the genus. This is the first report of a species of Bannoa from South America. [ABSTRACT FROM AUTHOR]

The diversity of yeasts has grown rapidly as the discovery of new species has benefited from intensified sampling and largely improved identification techniques. An environmental study typically reports the isolation of yeast species, some of which are new to science. Rare species represented by a few isolates often do not result in a taxonomic description. Nucleic acid sequences from these undescribed yeasts remain in public sequence databases, often without a proper taxonomic placement. This study presents a constrained phylogenetic analysis for many rare yeasts from unpublished but publicly available DNA sequences and from studies previously conducted by the authors of this work. We demonstrate that single isolates are an important source of taxonomic findings such as including new genera and species. Independent surveys performed during the last 20 years on a large geographic scale yielded a number of single strains, which were proved to be conspecific in the phylogenetic analyses presented here. The following new species were resolved and described: Vustinia terrea Kachalkin, Turchetti & Yurkov gen. nov. et sp. nov.; Udeniomyces caspiensis Kachalkin sp. nov.; Udeniomyces orazovii Kachalkin sp. nov.; Tausonia rosea Kachalkin sp. nov.; Itersonilia diksonensis Kachalkin sp. nov.; Krasilnikovozyma fibulata Glushakova & Kachalkin, Kwoniella fici Turchetti sp. nov.; Heterocephalacria fruticeti f.a. Carvalho, Roehl, Yurkov & Sampaio sp. nov.; Heterocephalacria gelida f.a. Turchetti & Kachalkin sp. nov.; Heterocephalacria hypogea f.a. Carvalho, Roehl, Yurkov & Sampaio sp. nov.; Heterocephalacria lusitanica f.a. Inacio, Carvalho, Roehl, Yurkov & Sampaio sp. nov.; Piskurozyma arborea Yurkov, Kachalkin, Mašínová & Baldrian sp. nov.; Piskurozyma silvicultrix Turchetti, Mašínová, Baldrian & Yurkov sp. nov.; Piskurozyma stramentorum Yurkov, Mašínová & Baldrian sp. nov.; Naganishia nivalis Turchetti sp. nov.; and Yurkovia nerthusi Yurkov & Begerow, sp. nov. In addition, two new combinations were proposed Krasilnikovozyma curviuscula (Babeva, Lisichkina, Reshetova & Danilevich) Yurkov, Kachalkin & Sampaio comb. nov. and Hannaella taiwanensis (F.L. Lee & C.H. Huang) Yurkov comb. nov. The order Cyphobasidiales T. Spribille & H. Mayrhofer is rejected in favor of the older name Erythrobasidiales R. Bauer, Begerow, J.P. Sampaio, M. Weiss & Oberwinkler. Other potential novel species identified in this paper await future description. Phylogenetic placement of yet unpublished sequences is believed to facilitate species descriptions and improve classification of yeasts from environmental sequence libraries. [ABSTRACT FROM AUTHOR]

Classicula sinensis, isolated from decaying leaves from Mozigou, Chongqing Municipality, China, is described as a new species. The new species is a member of basidiomycetous aquatic hyphomycetes which represent a small proportion of all aquatic hyphomycetes. This species falls within the genus Classicula (Classiculaceae, Pucciniomycotina) and is closely related to C. fluitans, based on multiple gene sequence analyses. Morphologically, it is characterised by the apical, hyaline, obclavate or navicular conidia with several hair-like lateral appendages and by its holoblastic and monoblastic conidiogenesis, with a flat un-thickened conidiogenous locus. Clamp connections and haustorial branches were often observed in culture. [ABSTRACT FROM AUTHOR]

Species of Coleosporium ( Pucciniales ) are rust fungi that typically alternate between pines and angiosperms. In North America, species of Coleosporium often infect Solidago (goldenrods), although their taxonomy on these hosts is unresolved. Joseph. C. Arthur and George B. Cummins regarded these as a single species, Coleosporium solidaginis (fide Arthur) or C. asterum (fide Cummins), but later inoculation studies demonstrated the presence of more than one species, distinguishable by their aecial hosts. A more recent taxonomic study of Coleosporium found that specimens on Solidago identified as C. asterum in North America were not conspecific with the type, which is from Japan, prompting the present study. Herein, we conducted a systematic study on ca. 60 collections of Coleosporium infecting species of Asteraceae from North America using regions of ribosomal DNA and morphology of teliospores and basidia. Our data indicate at least three species of Coleosporium occur on Solidago in North America, C. solidaginis , C. montanum comb. nov., which is proposed for the taxon that has commonly been identified as C. asterum in North America, and C. delicatulum , all of which can be differentiated by morphology of their basidia. In addition, the challenges of marker selection for molecular barcoding of rust fungi is discussed. [ABSTRACT FROM AUTHOR]

The anther smuts of the genus Microbotryum are known from host plant species belonging to the Caryophyllaceae, Dipsacaceae, Lamiaceae, Lentibulariaceae, Montiaceae, and Primulaceae. Of these, the anther smuts on Caryophyllaceae, in particular on Silene spp., are best known because they include model organisms studied in many disciplines of fungal biology. For Microbotryum species parasitic on Caryophyllaceae, a high degree of host specificity was revealed and several cryptic species were described. In contrast, the host specificity within Microbotryum pinguiculae occurring in anthers of different Pinguicula species (Lentibulariaceae) has not been investigated in detail until now. The anther smuts on Pinguicula alpina, P. villosa, and P. vulgaris, on which M. pinguiculae was described, were analyzed using nuc rDNA ITS1-5.8S-ITS2 and nuc rDNA 28S D1-D2 sequences and morphology to determine if they belong to one polyphagous species or rather represent three host-specific species. The results of the morphological investigations revealed no decisive differences between the anther smuts on different Pinguicula species. However, genetic divergence and molecular phylogenetic analyses, which split the specimens according to host plant species, supported host specificity of the anther smuts on different Pinguicula species. Accordingly, in addition to Microbotryum pinguiculae s. str. on Pinguicula vulgaris, M. alpinum sp. nov. on P. alpina from Europe and M. liroi sp. nov. on P. villosa from Asia are described and illustrated. [ABSTRACT FROM AUTHOR]

Rust fungi (Pucciniales) are the most speciose and the most complex group of plant pathogens. Historically, rust taxonomy was largely influenced by host and phenotypic characters, which are potentially plastic. Molecular systematic studies suggest that the extant diversity of this group was largely shaped by host jumps and subsequent shifts. However, it has been challenging to reconstruct the evolutionary history for the order, especially at deeper (family-level) nodes. Phylogenomics offer a potentially powerful tool to reconstruct the Pucciniales tree of life, although researchers working at this vanguard still face unprecedented challenges working with nonculturable organisms that possess some of the largest and most repetitive genomes now known in kingdom fungi. In this chapter, we provide an overview of the current status and special challenges of rust genomics, and we highlight how phylogenomics may provide new perspectives and answer long-standing questions regarding the biology of rust fungi. [ABSTRACT FROM AUTHOR]

Microbotryum bistortum, M. dianthorum, M. superbum and M. langerheimii, rare species of smut fungi are reported from new localities in Poland, mostly in protected areas. Dianthus superbus subsp. superbus is a new host for M. superbum observed. Taxonomical status of M. carthusianorum and M. superbum is discussed in the paper.

Tuberculina species represent the asexual life stage of the plant-parasitic sexual genus Helicobasidium . Tuberculina species are distributed all over the world, living in antagonistic symbiosis with over 150 rust species from at least 15 genera. Within the Basidiomycota , besides the spermogonia of rust fungi, only Tuberculina species develop distinct fructifications in the haplophase. However, the knowledge of conidiogenesis in Tuberculina is meagre. Therefore, conidial development in Tuberculina maxima, Tuberculina persicina, and Tuberculina sbrozzii was studied using transmission electron microscopy, and compared to each other as well as to spermatia formation in rust fungi. Significant ultrastructural characteristics such as the movement of nuclei in the process of conidium formation, and formation of the initial and late stages of conidiogenesis are documented. The mode of conidiogenesis of Tuberculina species is unique within the Basidiomycota in that (1) it is realized by haploid fructifications, (2) it is holoblastic, without annellidic proliferation, (3) the nucleus of the conidiogenous cell moves towards the forming conidium, divides, and no daughter nucleus remains inside the conidiogenous cell, and (4) the conidiogenous cell retains only cytoplasmic residues after the development of a single conidium, and a successive conidium is not produced. [ABSTRACT FROM AUTHOR]

Background: Rust fungi are obligate pathogens with multiple life stages often including different spore types and multiple plant hosts. While individual rust pathogens are often associated with specific plants, a wide range of plant species are infected with rust fungi. To study the interactions between these important pathogenic fungi and their host plants, one must be able to differentiate fungal tissue from plant tissue. This can be accomplished using the In situ hybridization (ISH) protocol described here. Results: To validate reproducibility using the ISH protocol, samples of Chrysanthemum x morifolium infected with Puccinia horiana, Gladiolus x hortulanus infected with Uromyces transversalis and Glycine max infected with Phakopsora pachyrhizi were tested alongside uninfected leaf tissue samples. The results of these tests show that this technique clearly distinguishes between rust pathogens and their respective host plant tissues. Conclusions: This ISH protocol is applicable to rust fungi and potentially other plant pathogenic fungi as well. It has been shown here that this protocol can be applied to pathogens from different genera of rust fungi with no background staining of plant tissue. We encourage the use of this protocol for the study of plant pathogenic fungi in paraffin embedded sections of host plant tissue. [ABSTRACT FROM AUTHOR]

Background: Patulin is a mycotoxin produced by Penicillium expansum, the causal agent of blue mold of stored pome fruits, and several other species of filamentous fungi. This mycotoxin has genotoxic, teratogenic and immunotoxic effects in mammals, and its presence in pome fruits and derived products represents a serious health hazard. Biocontrol agents in the Pucciniomycotina, such as the yeasts Sporobolomyces sp. strain IAM 13481 and Rhodosporidium kratochvilovae strain LS11, are able to resist patulin and degrade it into the less toxic compounds desoxypatulinic acid and ascladiol. Results: In this investigation we applied a transcriptomic approach based on RNAseq to annotate the genome of Sporobolomyces sp. IAM 13481 and then study the changes of gene expression in Sporobolomyces sp. exposed to patulin. Patulin treatment leads to ROS production and oxidative stress that result in the activation of stress response mechanisms controlled by transcription factors. Upregulated Sporobolomyces genes were those involved in oxidation-reduction and transport processes, suggesting the activation of defense mechanisms to resist patulin toxicity and expel the mycotoxin out of the cells. Other upregulated genes encoded proteins involved in metabolic processes such as those of the glutathione and thioredoxin systems, which are essential to restore the cellular redox homeostasis. Conversely, patulin treatment decreased the expression of genes involved in the processes of protein synthesis and modification, such as transcription, RNA processing, translation, protein phosphorylation and biosynthesis of amino acids. Also, genes encoding proteins involved in transport of ions, cell division and cell cycle were downregulated. This indicates a reduction of metabolic activity, probably due to the high energy requirement by the cells or metabolic arrest while recovering from the insult caused by patulin toxicity. Conclusions: Complex mechanisms are activated in a biocontrol yeast in response to patulin. The genes identified in this study can pave the way to develop i) a biodetoxification process of patulin in juices and ii) a biosensor for the rapid and cost-effective detection of this mycotoxin. [ABSTRACT FROM AUTHOR]

Zealand. Marine yeasts were isolated from various seaweed surfaces sampled at three locations in the Wellington Region. DNA sequencing of the internal transcribed spacer (ITS) regions was conducted, and the resultant sequence data were used in isolate identification. Yeasts isolated during this investigation were not unique; 71 isolates that are frequently detected in marine and terrestrial environments worldwide were identified from a range of seaweed genera. Furthermore, high ITS sequence similarity was observed between yeasts isolated during this investigation and those from geographically distant locations. These findings may indicate that marine yeasts are ubiquitous at a global level, although evidence is insufficient as to whether yeasts demonstrate biogeographic distribution patterns. Yeasts isolated during this investigation may have ecological implications in New Zealand's marine environment. Yeast isolates identified from seaweed genera have been demonstrated to have beneficial properties and applications and their potential should be explored. [ABSTRACT FROM AUTHOR]

The sexual morph of Aecidium goyazense collected in the Brazilian Cerrado was morphologically characterized by light microscopy and SEM, and shown to be a species of Uromyces, for which the name Uromyces hawksworthii nom. nov. is introduced, and designated as its epitype. This is the second Uromyces species known to infect the tropical genus Phthirusa (Loranthaceae). DNA sequences were generated from the ITS and 28S rRNA (LSU) regions of DNA recovered from aeciospores as well as teliospores. This fungus is compared with other Uromyces species known from Loranthaceae. [ABSTRACT FROM AUTHOR]

Many species of dimorphic basidiomycetes are known only in their asexual phase and typically those pigmented in different hues of red have been classified in the large polyphyletic genus Rhodotorula. These yeasts are ubiquitous and include a few species of some clinical relevance. The phylogenetic distribution of Rhodotorula spans three classes: Microbotryomycetes, Cystobasidiomycetes and Exobasidiomycetes. Here, the presented multi-gene analyses resolved phylogenetic relationships between the second largest group of Rhodotorula and the mycoparasite Cystobasidium fimetarium (Cystobasidiales, Cystobasidiomycetes, Pucciniomycotina). Based on the results, we propose the transfer of nine species belonging to the Rhodotorula minuta clade into the genus Cystobasidium. As a result, the clinically relevant species R. minuta will be renamed Cystobasidium minutum. This proposal follows ongoing reassessments of the anamorphic genus Rhodotorula reducing the polyphyly of this genus. The delimitation of the R. minuta clade from Rhodotorula species comprised in Sporidiobolales including the type species Rhodotorula glutinis is an important step to overcome obsolete generic placements of asexual basidiomycetous yeasts. Our proposal will also help to distinguish most common red yeasts from clinical samples such as members of Sporidiobolales and Cystobasidiales. The diagnosis of the genus Cystobasidium is amended by including additional characteristics known for the related group of species. The taxonomic change enables us to classify two novel species with the phylogenetically related members of the R. minuta clade in Cystobasidium. The recently from natural environments isolated species are described here as Cystobasidium psychroaquaticum f.a. sp. nov. (K-833 = KBP 3881 = VKPM Y-3653 = CBS 11769 = MUCL 52875 = DSM 27713) and Cystobasidium rietchiei f.a. sp. nov. (K-780 = KBP 4220 = VKPM Y-3658 = CBS 12324 = MUCL 53589 = DSM 27155). The new species were registered in MycoBank under MB 809336 and MB 809337, respectively. [ABSTRACT FROM AUTHOR]

Systematic relationships between the rusts on Goodeniaceae and Stylidiaceae were examined using phylogenetic analyses with two loci (internal transcribed spacer, large subunit region) from ribosomal DNA. Fresh specimens and herbarium material of four rust species ( Puccinia dampierae, P. gilgiana, P. saccardoi and Uromyces scaevolae) from the Goodeniaceae and one ( P. stylidii) from the Stylidiaceae were examined. A further species ( P. lagenophorae) that is reported from hosts in Goodeniaceae and Asteraceae was included in our analysis. Our phylogenetic analysis recovered the rusts on Goodeniaceae and Stylidiaceae in clades sister to P. lagenophorae on Asteraceae. This supported a taxonomy in which P. lagenophorae is restricted to Asteraceae. Descriptions or taxonomic notes are provided for all of the known rusts on Goodeniaceae and Stylidiaceae. [ABSTRACT FROM AUTHOR]

Paratritirachium is a recently described, monotypic, basidiomycete genus in the Pucciniomycotina with one described asexual species, P. cylindroconium. Three strains of an undescribed species of Paratritirachium were isolated from flare pit soils from Alberta, Canada, using a heat treatment method. Both asexual and sexual propagules were produced in culture. Asexual reproduction was characterized by unbranched or sparingly branched conidiophores and sympodial, slightly vesicular conidiogenous cells producing aseptate conidia. Distinctive curved basidia were commonly produced in culture, yielding two pale brown, thick-walled and oval basidiospores. The basidiospores were heat-resistant and germinated only when exposed to heat. Phylogenetic analyses using the internal transcribed spacer (ITS) region and the combined small and large ribosomal subunits confirmed that these isolates are a new species of Paratritirachium, described in this study as P. curvibasidium, and that Paratritirachium should be classified in the class Tritirachiomycetes, order Tritirachiales, and family Tritirachiaceae. Transmission electron microscopy revealed simple, uniperforate septa, similar to those of a Tritirachium species, supporting the placement of Paratritirachium in the class Tritirachiomycetes. This study provides the first description of sexual reproduction in the Tritirachiomycetes and the first report of basidiospore germination after heat treatment at a high temperature (75 °C). [ABSTRACT FROM AUTHOR]

Transposable elements (TEs) are ubiquitous genomic parasites that have prompted the evolution of genome defense systems that restrict their activity. Repeat-induced point mutation (RIP) is a homology-dependent genome defense that introduces C-to-T transition mutations in duplicated DNA sequences and is thought to control the proliferation of selfish repetitive DNA. Here, we determine the taxonomic distribution of hypermutation patterns indicative of RIP among basidiomycetes. We quantify C-to-T transition mutations in particular di- and trinucleotide target sites for TE-like sequences from nine fungal genomes. We find evidence of RIP-like patterns of hypermutation at TpCpG trinucleotide sites in repetitive sequences from all species of the Pucciniomycotina subphylum of the Basidiomycota, Microbotryum lychnidis-dioicae, Puccinia graminis, Melampsora laricis-populina, and Rhodotorula graminis. In contrast, we do not find evidence for RIP-like hypermutation in four species of the Agaricomycotina and Ustilaginomycotina subphyla of the Basidiomycota. Our results suggest that a RIP-like process and the specific nucleotide context for mutations are conserved within the Pucciniomycotina subphylum. These findings imply that coevolutionary interactions between TEs and a hypermutating genome defense are stable over long evolutionary timescales. [ABSTRACT FROM AUTHOR]

In this paper, we review historical and contemporary species concepts and species recognition criteria for plant pathogenic fungi. Previous incongruent and unstable classification based on subjective and changing criteria have led to some confusion, especially amongst plant pathologists. The goal of systematics is to provide an informative and robust framework that stands the test of time. The taxonomic histories of Cercospora, Colletotrichum, Fusarium, as well as the rust and smut fungi, are used as examples, to show how concepts and criteria used to delimit and recognize species have changed. Through these examples we compare the Genealogical Concordance Phylogenetic Species Recognition, an extension of the Phylogenetic Species Criterion, with other species recognition criteria and show that it provides a better discrimination for delimiting species. A rapidly increasing number of cryptic species are being discovered amongst plant pathogenic fungi using the Genealogical Concordance Phylogenetic Species Recognition, and it is important to determine their host range, the severity of diseases they cause and their biosecurity significance. With rapidly expanding global trade it has become imperative that we develop effective and reliable protocols to detect these previously unrecognized pathogens. [ABSTRACT FROM AUTHOR]

Abstract: Recent collections of Microbotryum (Pucciniomycotina, Basidiomycota) specimens inhabiting anthers of different caryophyllaceous host plants were analysed using LM and electron microscopy, as well as molecular phylogenetic analyses using rDNA (ITS and LSU) sequences. The phylogenetic relationships of caryophyllaceous anther parasites are discussed. Three new species, Microbotryum adenopetalae, M. minuartiae, and M. silenes-acaulis, are described based on morphological, ecological, and molecular characteristics. New host plants are reported for Microbotryum dianthorum (Dianthus jacquemontii and Petrorhagia saxifraga) and M. lychnidis-dioicae (Cucubalus baccifer and Silene zawadskii). For Microbotryum violaceum, a neotype is selected. [Copyright &y& Elsevier]

Abstract: The phylogeny of Auriculoscypha anacardiicola, an associate of scale insects in India, is investigated using subcellular characters and MP and Bayesian analyses of combined nuLSU-rDNA, nuSSU-rDNA and 5.8S rDNA sequence data. It has simple septa with a pulley-wheel-shaped pore plug, which is diagnostic of phytoparasitic members of the Pucciniomycetes, and hyphal wall break on branching, a phenomenon unique to some simple septate heterobasidiomycetes. The septal ultrastructure of A. anacardiicola is similar to that of the genus Septobasidium. The close relationship to Septobasidium is also confirmed by rDNA sequence analyses. The polyphyletic nature of the order Platygloeales, noted in earlier studies, is evident from the present molecular analysis as well. The placement of Auriculoscypha in the Platygloeales can no longer be justified and both ultrastructural and molecular evidence strongly support the placement of Auriculoscypha in the Septobasidiales. [Copyright &y& Elsevier]