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Background: As a genus within the Clavicipitaceae, Metarhizium exhibits rich morphological and ecological diversity, with a wide distribution and a variety of hosts. Currently, sixty-eight species of Metarhizium have been described. New information: A new species of Metarhizium, M.puerense (Hong Yu bis), was described in Pu'er City, Yunnan Province, south-western China. Based on morphological characteristics and multilocus phylogenetic analyses, Metarhiziumpuerense was confirmed to be phylogenetically related to M.album, but was clearly separated and formed a distinct branch. In contrast, the host of Metarhiziumalbum was plants and leafhoppers and that lepidopteran larvae were the host of M.puerense. The diagnostic features of M.puerense were solitary to multiple stromata and smooth-walled, cylindrical with rounded apices conidia.
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We evaluated the inclusion of a cryptic species in a Japanese Amanita caesareoides population. We sampled A. caesareoides specimens under various vegetation and climate conditions, and then conducted phylogenetic analyses on sequences from seven loci. The A. caesareoides specimens showed two distinct groups, except when the ITS phylogeny was considered. These two phylogroups showed different distributions: subalpine-cool temperate and temperate-subtropical areas. Although these two phylogroups overlapped in terms of basidiospore size, the latter tended to exhibit smaller basidiospores. In addition, only the former showed mycelial growth on nutrient agar. Based on these phylo-morpho-ecophysiological characteristics, we separated the specimens labeled with the name A. caesareoides into two species. As the lectotype of A. caesareoides showed similarity to the former by DNA analysis, the latter was described as a new species, namely A. satotamagotake. Based on the geographic patterns of the two species, A. satotamagotake may have invaded the natural habit of A. caesareoides because of global warming.
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During a survey of culturable microfungi from the bark of sugar maple (Acer saccharum), Atrocalyx glutinosus and Nigrograna rubescens, two novel species of Pleosporales (Dothideomycetes) were isolated from several locations in eastern Ontario, Canada. Formal species descriptions are presented based on unique colony phenotypes and micromorphological characteristics and supported using multi-locus molecular phylogenetic comparisons with similar species. Both A. glutinosus and N. rubescens produce pycnidial asexual morphs in culture. As their names imply, under specific culture conditions, A. glutinosus excretes large amounts of the glutinous polysaccharide pullulan and N. rubescens produces a dark red naphthoquinone pigment that diffuses in the culture medium. Citation: Mack JN, Sproule A, Shields SW, Seifert KA, Smith M, Overy DP (2024). Two novel Pleosporales species isolated from the bark of Acer saccharum . Fungal Systematics and Evolution 13: 1-14. doi: 10.3114/fuse.2024.13.01.
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Fungi are one of the most diverse groups of organisms on Earth, amongst which wood-inhabiting fungi play a crucial role in ecosystem processes and functions. Four new wood-inhabiting fungi, Xylodoncremeoparinaceus, X.luteodontioides, X.poroides and X.wumengshanensis are proposed, based on morphological features and molecular evidence. Xylodoncremeoparinaceus is distinguished by a cream hymenial surface with a pruinose hymenophore, a monomitic hyphal system with clamped generative hyphae and ellipsoid basidiospores. Xylodonluteodontioides is characterised by flavescens hymenophore surface with odontioid hymenophore, monomitic hyphal system with clamped generative hyphae and ellipsoid basidiospores. Xylodonporoides bears coriaceous basidiomata with a poroid hymenophore surface, monomitic hyphal system with clamped generative hyphae and ellipsoid basidiospores. Xylodonwumengshanensis is a distinct taxon by its grandinoid hymenophore surface, monomitic hyphal system with clamped generative hyphae and ellipsoid basidiospores. Sequences of ITS and nLSU rRNA markers of the studied samples were generated and phylogenetic analyses were performed using the Maximum Likelihood, Maximum Parsimony, and Bayesian Inference methods. The phylogram, based on the ITS+nLSU rDNA gene regions, included three genera within the Schizoporaceae as Fasciodontia, Lyomyces and Xylodon. The four new species were grouped into the genus Xylodon. The topology, based on the ITS sequences, revealed that Xylodoncremeoparinaceus was grouped closely with X.pruinosus, X.detriticus and X.ussuriensis. The taxon X.luteodontioides was sister to X.nesporii. The species X.poroides separated from X.pseudotropicus, while X.wumengshanensis was grouped with four taxa: X.patagonicus, X.radula, X.subtropicus and X.taiwanianus.
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Three new species belonging to Basidiomycota from southwestern China are described based on morphological and molecular data. Campanophyllummicrosporum is morphologically characterized by dorsally pseudostipitate, pale orange to brownish orange pileus, excentric to lateral pseudostipe, crowded lamellae, cylindrical-ellipsoid basidiospores 3.0-4.2 × 1.7-2.2 µm, narrowly clavate to clavate basidia 14.5-23.0 × 3.0-4.2 µm, and cylindrical to clavate cheilocystidia 22.0-55.0 × 5.0-10.8 µm. Caloceramultiramosa is morphologically characterized by stipitate, yellowish to orange, dendroid, and dichotomously branched basidiomata, cylindrical to clavate basidia 36.5-52.5 × 3.8-6.1 µm, navicular or reniform, 1-5-septate mature basidiospores 10.4-16.7 × 5.2-7.4 µm. Dacrymycesnaematelioides is morphologically characterized by stipitate and cerebriform, orange to light brown basidiomata, cylindrical to clavate, smooth or roughened basidia 38.5-79.5 × 6.5-10.6 µm, broadly and elliptic-fusiform, 7-septate mature basidiospores 18.5-28.6 × 8.9-13.8 µm. These three new species are supported by the phylogenetic analyses using maximum likelihood (ML) and Bayesian inference (BI) analyses with combined nuclear ribosomal DNA (rDNA) internal transcribed spacer (ITS) and large ribosomal subunit (LSU) sequences. Full descriptions and photographs of these new species are provided.
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Xenodidymella species have a wide range of hosts and can be found as pathogens and saprobes. In this study, two new species of Xenodidymella were found from leaf diseases of three pasture-medicinal plants in Ilam Province, in the west of Iran, and proposed here as X. ilamica and X. scandicis spp. nov. These species were identified based on morphological features and phylogenetic analyses of the internal transcribed spacer regions 1 & 2 and 5.8S nrDNA (ITS), partial beta-tubulin gene (tub2), and partial RNA polymerase II second largest subunit (rpb2) gene. The four Xenodidymella strains isolated in this study were delimited into two sister clades, with the two isolates of X. ilamica from the leaf spot of Colchicum speciosum and Ficaria kochii and two isolates of X. scandicis from leaf blight of Scandix pecten-veneris. Morphologically, X. scandicis produces larger, ostiolate or poroid pycnidia in vitro, while pycnidia in the cultures of X. ilamica are non-ostiolate and smaller. Some pycnidia in old cultures of X. scandicis produce a neck, but a distinct neck in X. ilamica has not been observed. Moreover, three plants under study are new hosts for the genus Xenodidymella.
Subject(s)
Phylogeny , Tubulin , Iran , Tubulin/genetics , Plants, Medicinal/microbiology , Plant Diseases/microbiology , Plant Leaves/microbiology , DNA, Fungal/genetics , RNA Polymerase II/genetics , Sequence Analysis, DNA , DNA, Ribosomal Spacer/geneticsABSTRACT
Anagyrus, a genus of Encyrtidae (Hymenoptera, Chalcidoidea), represents a successful group of parasitoid insects that attack various mealybug pests of agricultural and forestry plants. Until now, only 20 complete mitochondrial genomes have been sequenced, including those in this study. To enrich the diversity of mitochondrial genomes in Encyrtidae and to gain insights into their phylogenetic relationships, the mitochondrial genomes of two species of Anagyrus were sequenced, and the mitochondrial genomes of these species were compared and analyzed. Encyrtid mitochondrial genomes exhibit similarities in nucleotide composition, gene organization, and control region patterns. Comparative analysis of protein-coding genes revealed varying molecular evolutionary rates among different genes, with six genes (ATP8, ND2, ND4L, ND6, ND4 and ND5) showing higher rates than others. A phylogenetic analysis based on mitochondrial genome sequences supports the monophyly of Encyrtidae; however, the two subfamilies, Encyrtinae and Tetracneminae, are non-monophyletic. This study provides valuable insights into the phylogenetic relationships within the Encyrtidae and underscores the utility of mitochondrial genomes in the systematics of this family.
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Water hyacinth (Pontederia crassipes Mart.) is a monocotyledonous aquatic plant renowned for its rapid growth, extensive proliferation, biological invasiveness, and ecological resilience to variations in pH, nutrients, and temperature. The International Union for Conservation of Nature (IUCN) has listed P. crassipes among the top 100 invasive species. However, comprehensive genomic information, particularly concerning its mitochondrial genome (mitogenome), remains surprisingly limited. In this study, the complete mitogenome of P. crassipes was analyzed using bioinformatics approaches. The mitogenome is 399,263 bp long and contains 38 protein-coding genes (PCGs), 24 tRNA genes, and 3 rRNA genes. Sequence analysis revealed that the complete mitogenome of the species contains 3,289 dispersed repeats, and 765 RNA editing sites in protein-coding genes. The P. crassipes mitogenome possessed un-conserved structures, including extensive sequence transfer between its chloroplasts and mitochondria. Our study on the mitogenome of P. crassipes offers critical insights into its evolutionary patterns and phylogenetic relationships with related taxa. This research enhances our understanding of this invasive species, known for its significant biomass and rapid overgrowth in aquatic environments.
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Nairobi Sheep Disease (NSD) is a typical tick-borne syndrome characterized by severe hemorrhagic gastroenteritis, spontaneous abortion, and a high case fatality rate in small ruminants. The pathogenic agent, Nairobi sheep disease virus (NSDV), has also been associated with human infections, indicating its possible zoonotic potential. Prior to this study, NSDV has been detected from ticks collected in Jilin, Hubei, and Liaoning provinces in China. In the present study, a total of 343 ticks (Haemaphysalis longicornis) were collected in Shandong province, China in 2020, and pooled into 16 libraries. Analysis of the meta-transcriptomic sequencing data identified NSDV strains SDWL07, SDWL08, and SDWL16 from three pools. The SDWL07 and SDWL16 strains were detected from unfed ticks, while SDWL08 was detected from cattle-feeding ticks. Phylogenetic analyses showed higher sequence identities between the three strains and other Chinese NSDV strains than those from India and Kenya. Phylogenetic analyses also revealed that they clustered together and fell within the China lineage, suggesting no potential genetic reassortment among them. In summary, this is the first report of the identification of NSDV in Shandong province, highlighting the continually expanding endemic regions of this pathogen. Surveillance of NSDV should be intensified in China, especially in areas where H. longicornis is endemic.
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Hepatitis E virus (HEV) infection is prevalent among domestic pigs and wild boar in Europe. This study focused on the genetic diversity of HEV subtypes 3c, 3e and 3f among swine and wild boar in Europe as well as their circulation. Phylogenetic analysis and Bayesian phylogenetic inference were applied on the selected ORF2 capsid HEV sequences to co-estimate the viral circulation, the mean evolutionary rates and the dated trees. The estimated mean values of the HEV ORF2 capsid gene evolutionary rate were 8.29 x 10-3, 5.96 x 10-3, and 1.107 x 10-2 substitutions/site/year, respectively for 3c, 3e and 3f. The majority of the HEV 3c and 3e supported clusters did not show intermixing between swine and wild boar. Thus, although the intermixing observed in a minority of HEV 3c and 3e supported clusters suggests that transmission/circulation of these subtypes between swine and wild boar can potentially occur, 3c and 3e European wild boar HEV populations remained mainly segregated. In contrast, one half of the HEV 3f supported clusters showed intermixing between swine and wild boar, providing evidence for transfer/circulation to swine. The data suggest that continued virologic surveillance in swine and wild boar is necessary, together with targeted measures to reduce the chance of HEV transmission to humans.
Subject(s)
Hepatitis E virus , Hepatitis E , Phylogeny , Sus scrofa , Swine Diseases , Animals , Hepatitis E virus/genetics , Hepatitis E virus/classification , Hepatitis E virus/isolation & purification , Swine , Europe , Sus scrofa/virology , Hepatitis E/veterinary , Hepatitis E/virology , Hepatitis E/epidemiology , Swine Diseases/virology , Swine Diseases/epidemiology , Genetic VariationABSTRACT
Pestalotioid fungi are associated with a wide variety of plants around the world as pathogens, endophytes, and saprobes. In this study, diseased leaves and branches of plants were collected from Guizhou and Sichuan in China. Here, the fungal isolates were identified based on a phylogenetic analysis of the internal transcribed spacer region (ITS), the translation elongation factor 1-alpha (tef1-α) and the beta-tubulin (tub2) of ribosomal DNA, and the morphological characteristics. Ten Neopestalotiopsis isolates and two Pestalotiopsis isolates were obtained, and these isolates were further confirmed as four novel species (N. acericola, N. cercidicola, N. phoenicis, and P. guiyangensis) and one known species, N. concentrica.
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This study aims to report three new species of Conoideocrella and Moelleriella from Yunnan Province, Southwestern China. Species of Conoideocrella and Moelleriella parasitize scale insects (Coccidae and Lecaniidae, Hemiptera) and whiteflies (Aleyrodidae, Hemiptera). Based on the phylogenetic analyses of the three-gene nrLSU, tef-1α, and rpb1, it showed one new record species (Conoideocrella tenuis) and one new species (Conoideocrella fenshuilingensis sp. nov.) in the genus Conoideocrella, and two new species, i.e., Moelleriella longzhuensis sp. nov. and Moelleriella jinuoana sp. nov. in the genus Moelleriella. The three new species were each clustered into separate clades that distinguished themselves from one another. All of them were distinguishable from their allied species based on their morphology. Morphological descriptions, illustrations, and comparisons of the allied taxa of the four species are provided in the present paper. In addition, calculations of intraspecific and interspecific genetic distances were performed for Moelleriella and Conoideocrella.
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Rabbit coccidiosis is caused by infection with one or, more commonly, several Eimeria species that parasitize the hepatobiliary ducts or intestinal epithelium of rabbits. Currently, there are eleven internationally recognized species of rabbit coccidia, with the complete mitochondrial (mt) genomes of six species commonly infecting rabbits having been sequenced and annotated. Eimeria kongi was initially discovered in 2011 and prompted a preliminary study on this species. Through traditional morphological analysis, E. kongi was identified as a novel species of rabbit coccidia. To further validate this classification, we sequenced and annotated its mitochondrial genome. The complete mt genome of E. kongi spans 6258 bp and comprises three cytochrome genes (cytb, cox1, cox3), fourteen gene fragments for the large subunit (LSU) rRNA, and nine gene fragments for the small subunit (SSU) rRNA, lacking transfer RNA (tRNA) genes. Moreover, phylogenetic analysis of the mitochondrial genome sequence of E. kongi revealed its clustering with six other species of rabbit coccidia into a monophyletic group. Additionally, E. irresidua and E. flavescens were grouped within the lineage lacking oocyst residuum, consistent with their morphological characteristics. Consistent with multiple molecular phylogenies, in this investigation, E. kongi was further confirmed as a new species of rabbit coccidia. Our research findings are of great significance for the classification of coccidia and for coccidiosis prevention and control in rabbits.
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The giant triton snail, Charonia tritonis (Linnaeus, 1758), crucial for coral reef ecosystems as a primary predator of the crown-of-thorns sea star, is experiencing a significant decline due to overfishing for its ornamental shell, underscoring the urgent need for conservation and deeper understanding of its role within marine biodiversity. This study presents the first complete mitogenome sequence of C. tritonis. Spanning 15,346 bp, the C. tritonis mitogenome comprises 13 protein-coding genes (PCGs), 22 tRNA genes, and two rRNA genes. Phylogenetic analysis of 88 Littorinimorpha mitogenomes confirms C. tritonis and C. lampas are grouped together within the family Charoniidae as a sister group to the remaining Tonnoidea families. This research not only enhances the taxonomic classification and conservation efforts for marine gastropods but also serves as a vital reference for future evolutionary and genetic studies within the Caenogastropoda.
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BACKGROUND: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease. SFTS virus (SFTSV) is transmitted by tick bites and contact with the blood or body fluids of SFTS patients. Animal-to-human transmission of SFTS has been reported in Japan, but not in China. In this study, the possible transmission route of two patients who fed and cared for farm-raised fur animals in a mink farm was explored. METHOD: An epidemiological investigation and a genetic analysis of patients, animals and working environment were carried out. RESULTS: It was found that two patients had not been bitten by ticks and had no contact with patients infected with SFTS virus, but both of them had skinned the dying animals. 54.55% (12/22) of the farm workers were positive for SFTS virus antibody. By analyzing the large, medium and small segments sequences, the viral sequences from the two patients, animals and environments showed 99.9% homology. CONCLUSION: It is suspected that the two patients may be directly infected by farm-raised animals, and that the virus may have been transmitted by aerosols when skinning dying animals. Transmission by direct blood contacts or animal bites cannot be ignored.
Subject(s)
Phlebovirus , Severe Fever with Thrombocytopenia Syndrome , Animals , Humans , Antibodies, Viral/blood , China/epidemiology , Farmers , Farms , Mink/virology , Phlebovirus/genetics , Phlebovirus/isolation & purification , Phlebovirus/classification , Phylogeny , RNA, Viral/genetics , Severe Fever with Thrombocytopenia Syndrome/transmission , Severe Fever with Thrombocytopenia Syndrome/virology , Severe Fever with Thrombocytopenia Syndrome/epidemiologyABSTRACT
AIMS: Neocosmospora species are saprobes, endophytes, and pathogens belonging to the family Nectriaceae. This study aims to investigate the taxonomy, biosynthetic potential, and application of three newly isolated Neocosmospora species from mangrove habitats in the southern part of Thailand using phylogeny, bioactivity screening, genome sequencing, and bioinformatics analysis. METHODS AND RESULTS: Detailed descriptions, illustrations, and a multi-locus phylogenetic tree with large subunit ribosomal DNA (LSU), internal transcribed spacer (ITS), translation elongation factor 1-alpha (ef1-α), and RNA polymerase II second largest subunit (RPB2) regions showing the placement of three fungal strains, MFLUCC 17-0253, MFLUCC 17-0257, and MFLUCC 17-0259 clustered within the Neocosmospora clade with strong statistical support. Fungal crude extracts of the new species N. mangrovei MFLUCC 17-0253 exhibited strong antifungal activity to control Colletotrichum truncatum CG-0064, while N. ferruginea MFLUCC 17-0259 exhibited only moderate antifungal activity toward C. acutatum CC-0036. Thus, N. mangrovei MFLUCC 17-0253 was sequenced by Oxford nanopore technology. The bioinformatics analysis revealed that 49.17 Mb genome of this fungus harbors 41 potential biosynthetic gene clusters. CONCLUSION: Two fungal isolates of Neocosmospora and a new species of N. mangrovei were reported in this study. These fungal strains showed activity against pathogenic fungi causing anthracnose in chili. In addition, full genome sequencing and bioinformatics analysis of N. mangrovei MFLUCC 17-0253 were obtained.
Subject(s)
Avicennia , Colletotrichum , Phylogeny , Plant Diseases , Antifungal Agents/pharmacology , Ascomycota/genetics , Biological Control Agents , Colletotrichum/genetics , DNA, Fungal/genetics , Genome, Fungal , Plant Diseases/microbiology , Plant Diseases/prevention & control , Thailand , Avicennia/microbiologyABSTRACT
Fusarium spp. are commonly associated with the root rot complex of soybean (Glycine max). Previous surveys identified six common Fusarium species from Manitoba, including F. oxysporum, F. redolens, F. graminearum, F. solani, F. avenaceum, and F. acuminatum. This study aimed to determine their pathogenicity, assess host resistance, and evaluate the genetic diversity of Fusarium spp. isolated from Canada. The pathogenicity of these species was tested on two soybean cultivars, 'Akras' (moderately resistant) and 'B150Y1' (susceptible), under greenhouse conditions. The aggressiveness of the fungal isolates varied, with root rot severities ranging from 1.5 to 3.3 on a 0-4 scale. Subsequently, the six species were used to screen a panel of 20 Canadian soybean cultivars for resistance in a greenhouse. Cluster and principal component analyses were conducted based on the same traits used in the pathogenicity study. Two cultivars, 'P15T46R2' and 'B150Y1', were consistently found to be tolerant to F. oxysporum, F. redolens, F. graminearum, and F. solani. To investigate the incidence and prevalence of Fusarium spp. in Canada, fungi were isolated from 106 soybean fields surveyed across Manitoba, Saskatchewan, Ontario, and Quebec. Eighty-three Fusarium isolates were evaluated based on morphology and with multiple PCR primers, and phylogenetic analyses indicated their diversity across the major soybean production regions of Canada. Overall, this study contributes valuable insights into host resistance and the pathogenicity and genetic diversity of Fusarium spp. in Canadian soybean fields.
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Species of the family Polycephalomycetaceae grow on insects or entomopathogenic fungi and are distributed from tropical to subtropical regions. This study proposed four new species of hyperparasitic fungi from China based on six molecular markers (ITS, SSU, LSU, TEF-1α, RPB1 and RPB2) phylogenetic analyses and morphological characteristics. The four new species, i.e. Pleurocordycepslitangensis, Polycephalomycesjinghongensis, Po.multiperitheciatae and Po.myrmecophilus, were described and illustrated. Pl.litangensis, exhibiting a hyperparasitic lifestyle on Ophiocordycepssinensis, differed from Pleurocordyceps other species in producing subulate ß-phialides and ovoid or elliptic α-conidia. Po.jinghongensis was distinct from Polycephalomyces other species, being parasitic on Ophiocordyceps sp., as producing oval or long oval-shaped α-conidia and columns of ß-conidia. Po.multiperitheciatae differed from Polycephalomyces other species as having synnemata with fertile head, linear ß-conidia and parasitic on Ophiocordycepsmultiperitheciata. Po.myrmecophilus was distinct from Polycephalomyces other species, being parasitic on the fungus Ophiocordycepsacroasca, as producing round or ovoid α-conidia and elliptical ß-conidia without synnemata from the colonies. These four species were clearly distinguished from other species in the family Polycephalomycetaceae by phylogenetic and morphological characteristics. The morphological features were discussed and compared to relevant species in the present paper.
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Vararia is a species-rich genus in the family Peniophoraceae and has been shown to be polyphyletic. In this study, sequences of ITS and LSU rRNA markers of the studied samples were generated and phylogenetic analyses were performed with the maximum likelihood, maximum parsimony, and Bayesian inference methods. Seventeen lineages including six new species from China, i.e., V.fissurata, V.lincangensis, V.punctata, V.isabellina, V.sinensis, and V.yaoshanensis were recognized, in which V.fissurata is characterized by the brittle basidiomata with pruinose and cracking hymenophore having white to olivaceous buff hymenial surface, the clamped generative hyphae, presence of the two types gloeocystidia; V.lincangensis is characterized by the simple-septa generative hyphae, and thick-walled skeletal hyphae, and ellipsoid basidiospores; V.punctata is delimited by its thin to slightly thick-walled generative hyphae, and thick-walled skeletal hyphae, present thick-walled, clavate to cylindrical gloeocystidia; V.isabellina is characterized by having the cream to isabelline to slightly brown hymenial surface, thin to slightly thick-walled generative hyphae, and sub-fusiform to navicular basidiospores; V.sinensis is distinguishable by its white to slightly pink hymenial surface, thick-walled skeletal hyphae, and sub-fusiform to navicular basidiospores; V.yaoshanensis is characterized by cream to pinkish buff to cinnamon-buff hymenial surface, slightly thick-walled generative hyphae, the presence of two types gloeocystidia, and slightly thick-walled, ellipsoid basidiospores. Phylogram based on the ITS+nLSU rDNA gene regions included nine genera within the family Peniophoraceae as Amylostereum, Asterostroma, Baltazaria, Dichostereum, Michenera, Peniophora, Scytinostroma and Vararia, in which the six new wood-inhabiting fungi species were grouped into genus Vararia. The phylogenetic tree inferred from the combined ITS and LSU tree sequences highlighted that V.fissurata was found to be the sister to V.ellipsospora with strong supports. Additionally, V.lincangensis was clustered with V.fragilis. Furthermore, V.punctata was retrieved as a sister to V.ambigua. Moreover, V.sinensis was grouped with five taxa as V.breviphysa, V.pirispora, V.fusispora, V.abortiphysa and V.insolita. The new species V.isabellina formed a monophyletic lineage, in which it was then grouped closely with V.daweishanensis, and V.gracilispora. In addition, V.yaoshanensis was found to be the sister to V.gallica with strong supports. The present results increased the knowledge of Vararia species diversity and taxonomy of corticioid fungi in China. An identification key to 17 species of Vararia in China is provided.
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Head blight (HB) of oat (Avena sativa) has caused significant production losses in oats growing areas of western China. A total of 314 isolates, associated with HB were collected from the major oat cultivating areas of Gansu, Qinghai, and Yunnan Provinces in western China. Based on morphological characters, the isolates were initially classified into three genera, as differentiation to species was a bit difficult. Taxonomic analysis of these isolates based on muti-gene phylogenetic analyses (ITS, TEF1, TUB2, and RPB2) revealed four known Fusarium species, F. proliferatum, F. avenaceum, F. poae, and F. sibiricum, and one Acremonium specie (A. sclerotigenum). In addition, a new genus Neonalanthamala gen. nov., similar to genus Nalanthamala was introduced herein with a new combination, Neonalanthamala graminearum sp. nov., to accommodate the HB fungus. The molecular clock analyses estimated the divergence time of the Neonalanthamala and Nalanthamala based on a dataset (ITS, TUB2, RPB2), and we recognized the mean stem ages of the two genera are 98.95 Mya, which showed that they evolved from the same ancestor. N. graminearum was the most prevalent throughout the surveyed provinces. Pathogenicity test was carried out by using two different methods: seed inoculation and head inoculation. Results showed that F. sibiricum isolates were the most aggressive on the seed and head. A. sclerotigenum isolates were not pathogenic to seeds, and were developed less symptoms to the head compared to other species. Data analyses showed that the correlation of the germination potential, germination index, and dry weight of seed inoculation and disease index of plant inoculation had a highly significant negative correlation (P < 0.001). These results showed that the development of HB might be predicted by seed tests for this species. A. sclerotigenum and N. graminearum causing HB are being firstly reported on oat in the world. Similarly, F. proliferatum, F. avenaceum, F. poae and F. sibiricum causing oat HB are firstly reported in China.