Combined pangenomics and transcriptomics reveals core and redundant virulence processes in a rapidly evolving fungal plant pathogen.

BACKGROUND: Studying genomic variation in rapidly evolving pathogens potentially enables identification of genes supporting their "core biology", being present, functional and expressed by all strains or "flexible biology", varying between strains. Genes supporting flexible biology may be considered to be "accessory", whilst the "core" gene set is likely to be important for common features of a pathogen species biology, including virulence on all host genotypes. The wheat-pathogenic fungus Zymoseptoria tritici represents one of the most rapidly evolving threats to global food security and was the focus of this study. RESULTS: We constructed a pangenome of 18 European field isolates, with 12 also subjected to RNAseq transcription profiling during infection. Combining this data, we predicted a "core" gene set comprising 9807 sequences which were (1) present in all isolates, (2) lacking inactivating polymorphisms and (3) expressed by all isolates. A large accessory genome, consisting of 45% of the total genes, was also defined. We classified genetic and genomic polymorphism at both chromosomal and individual gene scales. Proteins required for essential functions including virulence had lower-than average sequence variability amongst core genes. Both core and accessory genomes encoded many small, secreted candidate effector proteins that likely interact with plant immunity. Viral vector-mediated transient in planta overexpression of 88 candidates failed to identify any which induced leaf necrosis characteristic of disease. However, functional complementation of a non-pathogenic deletion mutant lacking five core genes demonstrated that full virulence was restored by re-introduction of the single gene exhibiting least sequence polymorphism and highest expression. CONCLUSIONS: These data support the combined use of pangenomics and transcriptomics for defining genes which represent core, and potentially exploitable, weaknesses in rapidly evolving pathogens.

First Report of Leaf blight Caused by Stagonosporopsis citrulli on Garden Geranium in China.

Garden geranium (Pelargonium × hortorum L.H. Bailey, Geraniaceae) is a popular ornamental plant cultivated worldwide, whose extracts are used in cosmetics and medicine (Jugulam et al. 2001). On the University of Electronic Science and Technology of China campus (Chengdu, China), leaf blight on the garden geranium was observed during April-September 2021. The average disease incidence was around 40%-50%, which caused severe loss of ornamental value. Initially, circular, brown necrotic areas appear on the margin of the leaves. In the advanced stage of infection, lesions may enlarge rapidly, become irregular in shape, with the central portion of the lesion falling out and defoliation. To isolate the pathogen, symptomatic tissues obtained from diseased leaves were surface-sterilized for 1 min with 0.3% NaClO, rinsed in sterile distilled water, and plated onto potato dextrose agar (PDA). The inoculated plates were incubated for 7 days at 25°C. Successively, pure cultures were obtained by transferring hyphal tips to new PDA plates. A total of 20 isolates were obtained across 25 garden geranium plants investigated. The colonies on the PDA plates reached a diameter of 60-70 mm after 10 days at 25°C, spreading with a regular margin, aerial mycelium white, and black mycelia on the undersides cottony and solitary and globose pycnidia were produced after ten days. Conidia were either cylindrical or short cylindrical, hyaline 4-11 µm × 2-5 µm. These morphologies corresponded to those of Stagonosporopsis species. Sequence data for the 28S nrDNA, the internal transcribed spacer, ß-tubulin, and RNA polymerase II subunit (White et al. 1990, Liu et al. 1999, Aveskamp et al. 2009) were obtained randomly for one of the pure isolates (P1-L4-1-L1-1), which resulted in the GenBank accession numbers ON667723, ON667722, ON677462, and ON677463, respectively. The RAxML analysis (Stamatakis 2014) of the combined sequence data of the isolate P1-L4-1-L1-1 and the reference sequences obtained from GenBank demonstrated that the isolate P1-L4-1-L1-1 formed a strongly support clade with the type isolates (C5-5) of Stagonosporopsis citrulli M.T. Brewer & J.E. Stewart, which has been found on cucurbits (Stewart et al. 2015). The procedure for Koch's postulates was followed to confirm fungal pathogenicity using 4-day-old mycelial disks. A total of 15 same-aged healthy leaves were divided into three groups, and each group received a different treatment. Artificial wounds were created on one group of leaves using a sterile pin, and a 5-mm mycelial plug of the fungus was placed on the injured tissues. Mycelial plugs were also placed on the surfaces of the sets of unwounded leaves. The remaining leaves were maintained as control and inoculated with sterile PDA plugs. The test was repeated three times. Both the wounded and non-wounded leaves exhibited symptoms after 4-9 days identical to those observed in the field. The control group remained asymptomatic, and the morphology of the fungus reisolated from the inoculated leaves was similar to that of S. citrulli. The phylogeny, together with morphological identification and inoculation results, confirmed the identity of the pathogen on garden geranium as S. citrulli. To our knowledge, this is the first report of leaf spot caused by S. citrulli in the garden geranium in the world. Our results may help to provide crucial information for studying the epidemiology and management of this disease.

Fungal diversity notes 1512-1610: taxonomic and phylogenetic contributions on genera and species of fungal taxa.

This article is the 14th in the Fungal Diversity Notes series, wherein we report 98 taxa distributed in two phyla, seven classes, 26 orders and 50 families which are described and illustrated. Taxa in this study were collected from Australia, Brazil, Burkina Faso, Chile, China, Cyprus, Egypt, France, French Guiana, India, Indonesia, Italy, Laos, Mexico, Russia, Sri Lanka, Thailand, and Vietnam. There are 59 new taxa, 39 new hosts and new geographical distributions with one new combination. The 59 new species comprise Angustimassarina kunmingense, Asterina lopi, Asterina brigadeirensis, Bartalinia bidenticola, Bartalinia caryotae, Buellia pruinocalcarea, Coltricia insularis, Colletotrichum flexuosum, Colletotrichum thasutense, Coniochaeta caraganae, Coniothyrium yuccicola, Dematipyriforma aquatic, Dematipyriforma globispora, Dematipyriforma nilotica, Distoseptispora bambusicola, Fulvifomes jawadhuvensis, Fulvifomes malaiyanurensis, Fulvifomes thiruvannamalaiensis, Fusarium purpurea, Gerronema atrovirens, Gerronema flavum, Gerronema keralense, Gerronema kuruvense, Grammothele taiwanensis, Hongkongmyces changchunensis, Hypoxylon inaequale, Kirschsteiniothelia acutisporum, Kirschsteiniothelia crustaceum, Kirschsteiniothelia extensum, Kirschsteiniothelia septemseptatum, Kirschsteiniothelia spatiosum, Lecanora immersocalcarea, Lepiota subthailandica, Lindgomyces guizhouensis, Marthe asmius pallidoaurantiacus, Marasmius tangerinus, Neovaginatispora mangiferae, Pararamichloridium aquisubtropicum, Pestalotiopsis piraubensis, Phacidium chinaum, Phaeoisaria goiasensis, Phaeoseptum thailandicum, Pleurothecium aquisubtropicum, Pseudocercospora vernoniae, Pyrenophora verruculosa, Rhachomyces cruralis, Rhachomyces hyperommae, Rhachomyces magrinii, Rhachomyces platyprosophi, Rhizomarasmius cunninghamietorum, Skeletocutis cangshanensis, Skeletocutis subchrysella, Sporisorium anadelphiae-leptocomae, Tetraploa dashaoensis, Tomentella exiguelata, Tomentella fuscoaraneosa, Tricholomopsis lechatii, Vaginatispora flavispora and Wetmoreana blastidiocalcarea. The new combination is Torula sundara. The 39 new records on hosts and geographical distribution comprise Apiospora guiyangensis, Aplosporella artocarpi, Ascochyta medicaginicola, Astrocystis bambusicola, Athelia rolfsii, Bambusicola bambusae, Bipolaris luttrellii, Botryosphaeria dothidea, Chlorophyllum squamulosum, Colletotrichum aeschynomenes, Colletotrichum pandanicola, Coprinopsis cinerea, Corylicola italica, Curvularia alcornii, Curvularia senegalensis, Diaporthe foeniculina, Diaporthe longicolla, Diaporthe phaseolorum, Diatrypella quercina, Fusarium brachygibbosum, Helicoma aquaticum, Lepiota metulispora, Lepiota pongduadensis, Lepiota subvenenata, Melanconiella meridionalis, Monotosporella erecta, Nodulosphaeria digitalis, Palmiascoma gregariascomum, Periconia byssoides, Periconia cortaderiae, Pleopunctum ellipsoideum, Psilocybe keralensis, Scedosporium apiospermum, Scedosporium dehoogii, Scedosporium marina, Spegazzinia deightonii, Torula fici, Wiesneriomyces laurinus and Xylaria venosula. All these taxa are supported by morphological and multigene phylogenetic analyses. This article allows the researchers to publish fungal collections which are important for future studies. An updated, accurate and timely report of fungus-host and fungus-geography is important. We also provide an updated list of fungal taxa published in the previous fungal diversity notes. In this list, erroneous taxa and synonyms are marked and corrected accordingly.

Insights into taxonomic diversity and bioprospecting potential of Cerrado endophytic fungi: a review exploring an unique Brazilian biome and methodological limitations.

Cerrado is the second largest biome in Brazil, and it is known for harboring a wide variety of endemic plant and microbial species, among which are endophytic fungi. Endophytic fungi are microorganisms capable of colonizing the interior of plant tissues without causing disease in host plants. Especially in the Cerrado biome, this group of microorganisms is still poorly studied and information on species estimation, ecological and evolutionary importance is not accurate and remains unknown. Also, it is extremely important to emphasize that great part of studies available on Cerrado endophytic fungi are national literature, including master's dissertations, course conclusion works or unpublished doctoral theses. The majority of these studies has highlighted that the endemic plant species are an important habitat for fungal endophytes, and new species have increasingly been described. Due to the lack of international literature on Cerrado endophytic fungi, the present review brings a bibliographic survey on taxonomic diversity and bioprospecting potential of fungal endophytes from a unique environment. This review also emphasizes the importance of studying Brazilian endophytic fungi from Cerrado as a source of new technologies (biofertilizer and biocontroller), since they are secondary metabolite-producing organisms with different biological activities for biotechnological, agricultural and pharmaceutical applications.

Fungal diversity notes 1387-1511: taxonomic and phylogenetic contributions on genera and species of fungal taxa.

This article is the 13th contribution in the Fungal Diversity Notes series, wherein 125 taxa from four phyla, ten classes, 31 orders, 69 families, 92 genera and three genera incertae sedis are treated, demonstrating worldwide and geographic distribution. Fungal taxa described and illustrated in the present study include three new genera, 69 new species, one new combination, one reference specimen and 51 new records on new hosts and new geographical distributions. Three new genera, Cylindrotorula (Torulaceae), Scolecoleotia (Leotiales genus incertae sedis) and Xenovaginatispora (Lindomycetaceae) are introduced based on distinct phylogenetic lineages and unique morphologies. Newly described species are Aspergillus lannaensis, Cercophora dulciaquae, Cladophialophora aquatica, Coprinellus punjabensis, Cortinarius alutarius, C. mammillatus, C. quercoflocculosus, Coryneum fagi, Cruentomycena uttarakhandina, Cryptocoryneum rosae, Cyathus uniperidiolus, Cylindrotorula indica, Diaporthe chamaeropicola, Didymella azollae, Diplodia alanphillipsii, Dothiora coronicola, Efibula rodriguezarmasiae, Erysiphe salicicola, Fusarium queenslandicum, Geastrum gorgonicum, G. hansagiense, Helicosporium sexualis, Helminthosporium chiangraiensis, Hongkongmyces kokensis, Hydrophilomyces hydraenae, Hygrocybe boertmannii, Hyphoderma australosetigerum, Hyphodontia yunnanensis, Khaleijomyces umikazeana, Laboulbenia divisa, Laboulbenia triarthronis, Laccaria populina, Lactarius pallidozonarius, Lepidosphaeria strobelii, Longipedicellata megafusiformis, Lophiotrema lincangensis, Marasmius benghalensis, M. jinfoshanensis, M. subtropicus, Mariannaea camelliae, Melanographium smilaxii, Microbotryum polycnemoides, Mimeomyces digitatus, Minutisphaera thailandensis, Mortierella solitaria, Mucor harpali, Nigrograna jinghongensis, Odontia huanrenensis, O. parvispina, Paraconiothyrium ajrekarii, Parafuscosporella niloticus, Phaeocytostroma yomensis, Phaeoisaria synnematicus, Phanerochaete hainanensis, Pleopunctum thailandicum, Pleurotheciella dimorphospora, Pseudochaetosphaeronema chiangraiense, Pseudodactylaria albicolonia, Rhexoacrodictys nigrospora, Russula paravioleipes, Scolecoleotia eriocamporesi, Seriascoma honghense, Synandromyces makranczyi, Thyridaria aureobrunnea, Torula lancangjiangensis, Tubeufia longihelicospora, Wicklowia fusiformispora, Xenovaginatispora phichaiensis and Xylaria apiospora. One new combination, Pseudobactrodesmium stilboideus is proposed. A reference specimen of Comoclathris permunda is designated. New host or distribution records are provided for Acrocalymma fici, Aliquandostipite khaoyaiensis, Camarosporidiella laburni, Canalisporium caribense, Chaetoscutula juniperi, Chlorophyllum demangei, C. globosum, C. hortense, Cladophialophora abundans, Dendryphion hydei, Diaporthe foeniculina, D. pseudophoenicicola, D. pyracanthae, Dictyosporium pandanicola, Dyfrolomyces distoseptatus, Ernakulamia tanakae, Eutypa flavovirens, E. lata, Favolus septatus, Fusarium atrovinosum, F. clavum, Helicosporium luteosporum, Hermatomyces nabanheensis, Hermatomyces sphaericoides, Longipedicellata aquatica, Lophiostoma caudata, L. clematidis-vitalbae, Lophiotrema hydei, L. neoarundinaria, Marasmiellus palmivorus, Megacapitula villosa, Micropsalliota globocystis, M. gracilis, Montagnula thailandica, Neohelicosporium irregulare, N. parisporum, Paradictyoarthrinium diffractum, Phaeoisaria aquatica, Poaceascoma taiwanense, Saproamanita manicata, Spegazzinia camelliae, Submersispora variabilis, Thyronectria caudata, T. mackenziei, Tubeufia chiangmaiensis, T. roseohelicospora, Vaginatispora nypae, Wicklowia submersa, Xanthagaricus necopinatus and Xylaria haemorrhoidalis. The data presented herein are based on morphological examination of fresh specimens, coupled with analysis of phylogenetic sequence data to better integrate taxa into appropriate taxonomic ranks and infer their evolutionary relationships.

Genome Sequence Data of the Soybean Pathogen Stagonosporopsis vannaccii: A Resource for Studies on Didymellaceae Evolution.

The genus Stagonosporopsis is classified within the Didymellaceae family and has around 40 associated species. Among them, several species are important plant pathogens responsible for significant losses in economically important crops worldwide. Stagonosporopsis vannaccii is a newly described species pathogenic to soybean. Here, we present the draft whole-genome sequence, gene prediction, and annotation of S. vannaccii isolate LFN0148 (also known as IMI 507030). To our knowledge, this is the first genome sequenced of this species and represents a new useful source for future research on fungal comparative genomics studies.

First Draft Genome Resource for the Tomato Black Leaf Mold Pathogen Pseudocercospora fuligena.

Pseudocercospora fuligena is a fungus that causes black leaf mold, an important disease of tomato in tropical and subtropical regions of the world. Despite its economic importance, genomic resources for this pathogen are scarce and no reference genome was available thus far. Here, we report a 50.6-Mb genome assembly for P. fuligena, consisting of 348 contigs with an N50 value of 0.407 Mb. In total, 13,764 protein-coding genes were predicted with an estimated BUSCO completeness of 98%. Among the predicted genes there were 179 candidate effectors, 445 carbohydrate-active enzymes, and 30 secondary metabolite gene clusters. The resources presented in this study will allow genome-wide comparative analyses and population genomic studies of this pathogen, ultimately improving management strategies for black leaf mold of tomato.

Alpha-Glucosidase- and Lipase-Inhibitory Phenalenones from a New Species of Pseudolophiostoma Originating from Thailand.

The alpha-glucosidase- and lipase-inhibitory activities of three phenalenones (1-3) and one phenylpropanoid (4) from the ethyl acetate extracts of a Pseudolophiosptoma sp. are described. They represent the first secondary metabolites reported from the genus Pseudolophiostoma. Scleroderolide (1) and sclerodione (2) exhibited potent α-glucosidase- and porcine-lipase-inhibitory activity during primary screening, with better IC50 values compared to the positive controls, N-deoxynojirimycin and orlistat. In silico techniques were employed to validate the probable biological targets and elucidate the mechanism of actions of phenalenones 1 and 2. Both compounds exhibited strong binding affinities to both alpha-glucosidase and porcine lipase through H-bonding and π-π interactions. Interestingly, favorable in silico ADME (absorption, distribution, metabolism, and excretion) properties such as gastrointestinal absorption were also predicted using software.

Fenestelloid clades of the Cucurbitariaceae.

Fresh collections and their ascospore and conidial isolates backed up by type studies and molecular phylogenetic analyses of a multigene matrix of partial nuSSU-, complete ITS, partial LSU rDNA, rpb2, tef1 and tub2 sequences were used to evaluate the boundaries and species composition of Fenestella and related genera of the Cucurbitariaceae. Eight species, of which five are new, are recognised in Fenestella s.str., 13 in Parafenestella with eight new species and two in the new genus Synfenestella with one new species. Cucurbitaria crataegi is combined in Fenestella, C. sorbi in Synfenestella, Fenestella faberi and Thyridium salicis in Parafenestella. Cucurbitaria subcaespitosa is distinct from C. sorbi and combined in Neocucurbitaria. Fenestella minor is a synonym of Valsa tetratrupha, which is combined in Parafenestella. Cucurbitaria marchica is synonymous with Parafenestella salicis, Fenestella bavarica with S. sorbi, F. macrospora with F. media, and P. mackenziei is synonymous with P. faberi, and the latter is lectotypified. Cucurbitaria sorbi, C. subcaespitosa and Fenestella macrospora are lecto- and epitypified, Cucurbitaria crataegi, Fenestella media, F. minor and Valsa tetratrupha are epitypified in order to stabilise the names in their phylogenetic positions. A neotype is proposed for Thyridium salicis. A determinative key to species is given. Asexual morphs of fenestelloid fungi are phoma-like and do not differ from those of other representatives of the Cucurbitariaceae. The phylogenetic structure of the fenestelloid clades is complex and can only be resolved at the species level by protein-coding genes, such as rpb2, tef1 and tub2. All fungal species studied here occur, as far as has been possible to determine, on members of Diaporthales, most frequently on asexual and sexual morphs of Cytospora.

Biotechnological application of endophytic filamentous bipolaris and curvularia: a review on bioeconomy impact.

The filamentous Bipolaris and Curvularia genera consist of species known to cause severe diseases in plants and animals amounting to an estimated annual loss of USD $10 billion worldwide. Despite the harmful effect of Bipolaris and Curvularia species, scarce attention is paid on beneficial areas where the fungi are used in industrial processes to generate biotechnological products. Catalytic potential of Bipolaris and Curvularia species in the production of biodiesel, bioflucculant, biosorbent, and mycoherbicide are promising for the bioeconomy. It is herein demonstrated that knowledge-based application of some endophytic Bipolaris and Curvularia species are indispensable vectors of sustainable economic development. In the twenty-first century, India, China, and the USA have taken progress in the biotechnological application of these fungi to generate wealth. As such, some Bipolaris and Curvularia species significantly impact on global crop improvement, act as catalyst in batch-reactors for biosynthesis of industrial enzymes and medicines, bioengineer of green-nanoparticle, agent of biofertilizer, bioremediation and bio-hydrometallurgy. For the first time, this study discusses the current advances in biotechnological application of Bipolaris and Curvularia species and provide new insights into the prospects of optimizing their bioengineering potential for developing bioeconomy.

Fungal Systematics and Evolution: FUSE 5.

Thirteen new species are formally described: Cortinarius brunneocarpus from Pakistan, C. lilacinoarmillatus from India, Curvularia khuzestanica on Atriplex lentiformis from Iran, Gloeocantharellus neoechinosporus from China, Laboulbenia bernaliana on species of Apenes, Apristus, and Philophuga (Coleoptera, Carabidae) from Nicaragua and Panama, L. oioveliicola on Oiovelia machadoi (Hemiptera, Veliidae) from Brazil, L. termiticola on Macrotermes subhyalinus (Blattodea, Termitidae) from the DR Congo, Pluteus cutefractus from Slovenia, Rhizoglomus variabile from Peru, Russula phloginea from China, Stagonosporopsis flacciduvarum on Vitis vinifera from Italy, Strobilomyces huangshanensis from China, Uromyces klotzschianus on Rumex dentatus subsp. klotzschianus from Pakistan. The following new records are reported: Alternaria calendulae on Calendula officinalis from India; A. tenuissima on apple and quince fruits from Iran; Candelariella oleaginescens from Turkey; Didymella americana and D. calidophila on Vitis vinifera from Italy; Lasiodiplodia theobromae causing tip blight of Dianella tasmanica 'variegata' from India; Marasmiellus subpruinosus from Madeira, Portugal, new for Macaronesia and Africa; Mycena albidolilacea, M. tenuispinosa, and M. xantholeuca from Russia; Neonectria neomacrospora on Madhuca longifolia from India; Nothophoma quercina on Vitis vinifera from Italy; Plagiosphaera immersa on Urtica dioica from Austria; Rinodina sicula from Turkey; Sphaerosporium lignatile from Wisconsin, USA; and Verrucaria murina from Turkey. Multi-locus analysis of ITS, LSU, rpb1, tef1 sequences revealed that P. immersa, commonly classified within Gnomoniaceae (Diaporthales) or as Sordariomycetes incertae sedis, belongs to Magnaporthaceae (Magnaporthales). Analysis of a six-locus Ascomycota-wide dataset including SSU and LSU sequences of S. lignatile revealed that this species, currently in Ascomycota incertae sedis, belongs to Pyronemataceae (Pezizomycetes, Pezizales).

Two new classes of Ascomycota: Xylobotryomycetes and Candelariomycetes.

Phylogenetic analyses of a combined DNA data matrix containing nuclear small and large subunits (nSSU, nLSU) and mitochondrial small subunit (mtSSU) ribosomal RNA and the largest and second largest subunits of the RNA polymerase II (rpb1, rpb2) of representative Pezizomycotina revealed that the enigmatic genera Xylobotryum and Cirrosporium form an isolated, highly supported phylogenetic lineage within Leotiomyceta. Acknowledging their morphological and phylogenetic distinctness, we describe the new class Xylobotryomycetes, containing the new order Xylobotryales with the two new families Xylobotryaceae and Cirrosporiaceae. The two currently accepted species of Xylobotryum, X. andinum and X. portentosum, are described and illustrated by light and scanning electron microscopy. The generic type species X. andinum is epitypified with a recent collection for which a culture and sequence data are available. Acknowledging the phylogenetic distinctness of Candelariomycetidae from Lecanoromycetes revealed in previous and the current phylogenetic analyses, the new class Candelariomycetes is proposed.

Re-evaluation of Mycoleptodiscus species and morphologically similar fungi.

Mycoleptodiscus includes plant pathogens, animal opportunists, saprobic and endophytic fungi. The present study presents the first molecular phylogeny and revision of the genus based on four loci, including ITS, LSU, rpb2, and tef1. An extensive collection of Mycoleptodiscus cultures, including ex-type strains from the CBS, IMI, MUCL, BRIP, clinical isolates from the USA, and fresh isolates from Brazil and Spain, was studied morphologically and phylogenetically to resolve their taxonomy. The study showed that Mycoleptodiscus sensu lato is polyphyletic. Phylogenetic analysis places Mycoleptodiscus in Muyocopronales (Dothideomycetes), together with Arxiella, Leptodiscella, Muyocopron, Neocochlearomyces, and Paramycoleptodiscus. Mycoleptodiscus terrestris, the type species, and M. sphaericus are reduced to synonyms, and one new species is introduced, M. suttonii. Mycoleptodiscus atromaculans, M. coloratus, M. freycinetiae, M. geniculatus, M. indicus, M. lateralis (including M. unilateralis and M. variabilis as its synonyms) and M. taiwanensis belong to Muyocopron (Muyocopronales, Dothideomycetes), and M. affinis, and M. lunatus to Omnidemptus (Magnaporthales, Sordariomycetes). Based on phylogenetic analyses we propose Muyocopron alcornii sp. nov., a fungus associated with leaf spots on Epidendrum sp. (Orchidaceae) in Australia, Muyocopron zamiae sp. nov. associated with leaf spots on Zamia (Zamiaceae) in the USA, and Omnidemptus graminis sp. nov. isolated from a grass (Poaceae) in Spain. Furthermore, Neomycoleptodiscus venezuelense gen. & sp. nov. is introduced for a genus similar to Mycoleptodiscus in Muyocopronaceae.

Evolution of the mating types and mating strategies in prominent genera in the Botryosphaeriaceae.

Little is known regarding mating strategies in the Botryosphaeriaceae. To understand sexual reproduction in this fungal family, the mating type genes of Botryosphaeria dothidea and Macrophomina phaseolina, as well as several species of Diplodia, Lasiodiplodia and Neofusicoccum were characterized from whole genome assemblies. Comparisons between the mating type loci of these fungi showed that the mating type genes are highly variable, but in most cases the organization of these genes is conserved. Of the species considered, nine were homothallic and seven were heterothallic. Mating type gene fragments were discovered flanking the mating type regions, which indicates both ongoing and ancestral recombination occurring within the mating type region. Ancestral reconstruction analysis further indicated that heterothallism is the ancestral state in the Botryosphaeriaceae and this is supported by the presence of mating type gene fragments in homothallic species. The results also show that at least five transitions from heterothallism to homothallism have taken place in the Botryosphaeriaceae. The study provides a foundation for comparison of mating type evolution between Botryosphaeriaceae and other fungi and also provides valuable markers for population biology studies in this family.

A preliminary account of the Cucurbitariaceae.

Fresh collections, type studies and molecular phylogenetic analyses of a multigene matrix of partial nuSSU-ITS-LSU rDNA, rpb2, tef1 and tub2 sequences were used to evaluate the boundaries of Cucurbitaria in a strict sense and of several related genera of the Cucurbitariaceae. Two species are recognised in Cucurbitaria and 19 in Neocucurbitaria. The monotypic genera Astragalicola, Cucitella, Parafenestella, Protofenestella, and Seltsamia are described as new. Fenestella is here included as its generic type F. fenestrata (= F. princeps), which is lecto- and epitypified. Fenestella mackenzei and F. ostryae are combined in Parafenestella. Asexual morphs of Cucurbitariaceae, where known, are all pyrenochaeta- or phoma-like. Comparison of the phylogenetic analyses of the ITS-LSU and combined matrices demonstrate that at least rpb2 sequences should be added whenever possible to improve phylogenetic resolution of the tree backbone; in addition, the tef1 introns should be added as well to improve delimitation of closely related species.

Two unusual new species of Pleosporales: Anteaglonium rubescens and Atrocalyx asturiensis.

Two new species of Pleosporales, Anteaglonium rubescens (Anteagloniaceae) and Atrocalyx asturiensis (Lophiotremataceae), are described. Phylogenetic placement was determined by combined analyses of a DNA data matrix containing ITS, LSU, SSU, rpb2, and tef1. Anteaglonium rubescens is a stromatic fungus characterized by brown didymospores disarticulating within asci, and by the production of a red-orange to pink pigment produced in nature and in artificial culture. Atrocalyx asturiensis has massive ascomatal crests and brown phragmospores.

ITS1 metabarcoding highlights low specificity of lichen mycobiomes at a local scale.

As self-supporting and long-living symbiotic structures, lichens provide a habitat for many other organisms beside the traditionally considered lichen symbionts-the myco- and the photobionts. The lichen-inhabiting fungi either develop diagnostic phenotypes or occur asymptomatically. Because the degree of specificity towards the lichen host is poorly known, we studied the diversity of these fungi among neighbouring lichens on rocks in an alpine habitat. Using a sequencing metabarcoding approach, we show that lichen mycobiomes clearly reflect the overlap of multiple ecological sets of taxa, which differ in their trophic association with lichen thalli. The lack of specificity to the lichen mycobiome is further supported by the lack of community structure observed using clustering and ordination methods. The communities encountered across samples largely result from the subsampling of a shared species pool, in which we identify three major ecological components: (i) a generalist environmental pool, (ii) a lichenicolous/endolichenic pool and (iii) a pool of transient species. These taxa majorly belong to the fungal classes Dothideomycetes, Eurotiomycetes and Tremellomycetes with close relatives in adjacent ecological niches. We found no significant evidence that the phenotypically recognized lichenicolous fungi influence the occurrence of the other asymptomatic fungi in the host thalli. We claim that lichens work as suboptimal habitats or as a complex spore and mycelium bank, which modulate and allow the regeneration of local fungal communities. By performing an approach that minimizes ambiguities in the taxonomic assignments of fungi, we present how lichen mycobiomes are also suitable targets for improving bioinformatic analyses of fungal metabarcoding.

Corynespora, Exosporium and Helminthosporium revisited - New species and generic reclassification.

Molecular phylogenetic analyses of a multigene matrix of partial nuSSU-ITS-LSU rDNA, rpb2 and tef1 sequences were performed to investigate the phylogenetic relationships of Corynespora, Exosporium and Helminthosporium species. Based on phylogenetic analyses and morphology, the genus Exosporium is synonymised with Helminthosporium, and the genus Corynespora is revealed as polyphyletic. Corynespora smithii is confirmed to be closely related to the generic type C. cassiicola and its morphology is described and illustrated. Exosporium tiliae, Corynespora caespitosa, C. endiandrae, C. leucadendri and C. olivacea are recognised in Helminthosporium, and Splanchnonema quercicola and S. kalakadense are combined in Helminthosporium. Based on pure culture studies and DNA sequence data, Massaria heterospora and Massarinula italica are shown to be the sexual morphs of Helminthosporium tiliae and H. microsorum, respectively. European accessions of Splanchnonema quercicola are recognised to differ from the North American type and are described as Helminthosporium quercinum. The sexual morph of H. oligosporum is recorded and described for the first time. The generic type of Helminthosporium, H. velutinum, is epitypified with a recent collection from the type host, Fagus sylvatica. Based on sequence data, Helminthosporium genistae is recognised as a distinct species. Several species for which subperidermal stromata have been reported are shown to be fungicolous on Diaporthales, the "stromata" representing aborted and transformed host stromata or conidiomata: H. caespitosum, H. microsorum, H. quercicola and H. quercinum on Coryneum spp.; H. hispanicum on conidiomata of Juglanconis juglandina; H. juglandinum on conidiomata of Diaporthe sp.; H. oligosporum and H. tiliae on Hercospora tiliae. The newly described H. austriacum is fungicolous on Amphisphaeria cf. millepunctata (Xylariales).

Phylogeny of saprobic microfungi from Southern Europe.

During a survey of saprophytic microfungi on decomposing woody, herbaceous debris and soil from different regions in Southern Europe, a wide range of interesting species of asexual ascomycetes were found. Phylogenetic analyses based on partial gene sequences of SSU, LSU and ITS proved that most of these fungi were related to Sordariomycetes and Dothideomycetes and to lesser extent to Leotiomycetes and Eurotiomycetes. Four new monotypic orders with their respective families are proposed here, i.e. Lauriomycetales, Lauriomycetaceae; Parasympodiellales, Parasympodiellaceae; Vermiculariopsiellales, Vermiculariopsiellaceae and Xenospadicoidales, Xenospadicoidaceae. One new order and three families are introduced here to accommodate orphan taxa, viz. Kirschsteiniotheliales, Castanediellaceae, Leptodontidiaceae and Pleomonodictydaceae. Furthermore, Bloxamiaceae is validated. Based on morphology and phylogenetic affinities Diplococcium singulare, Trichocladium opacum and Spadicoides atra are moved to the new genera Paradiplococcium, Pleotrichocladium and Xenospadicoides, respectively. Helicoon fuscosporum is accommodated in the genus Magnohelicospora. Other novel genera include Neoascotaiwania with the type species N. terrestris sp. nov., and N. limnetica comb. nov. previously accommodated in Ascotaiwania; Pleomonodictys with P. descalsii sp. nov. as type species, and P. capensis comb. nov. previously accommodated in Monodictys; Anapleurothecium typified by A. botulisporum sp. nov., a fungus morphologically similar to Pleurothecium but phylogenetically distant; Fuscosclera typified by F. lignicola sp. nov., a meristematic fungus related to Leotiomycetes; Pseudodiplococcium typified by P. ibericum sp. nov. to accommodate an isolate previously identified as Diplococcium pulneyense; Xyladictyochaeta typified with X. lusitanica sp. nov., a foliicolous fungus related to Xylariales and similar to Dictyochaeta, but distinguished by polyphialidic conidiogenous cells produced on setiform conidiophores. Other novel species proposed are Brachysporiella navarrica, Catenulostroma lignicola, Cirrenalia iberica, Conioscypha pleiomorpha, Leptodontidium aureum, Pirozynskiella laurisilvatica, Parasympodiella lauri and Zanclospora iberica. To fix the application of some fungal names, lectotypes and/or epitypes are designated for Magnohelicospora iberica, Sporidesmium trigonellum, Sporidesmium opacum, Sporidesmium asperum, Camposporium aquaticum and Psilonia atra.