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Fabaceae, one of the largest flowering plant families, comprises several subfamilies and genera. Fabaceous plant species host a large number of powdery mildew species belonging to the genus Erysiphe. The affiliation of these species to Erysiphe is readily possible, but they represent a morphologically and taxonomically complicated complex of closely related, morphologically similar species with overlapping traits. Precise morphological examinations along with phylogenetic analyses, including type collections and other representative samples, are needed to solve the complexity of Erysiphe spp. on legumes. In this study, we sequenced a number of collections of powdery mildews on Pisum, Lathyrus, Vicia and Ononis spp., with a special focus on specimens from Iran, to clarify species delimitations within the Erysiphe pisi complex and other Erysiphe species complexes on legumes. Sequences retrieved from powdery mildew on Pisum and Ononis fall into separate, well supported clades. Hence, the original status of E. cruchetiana as a species of its own on Ononis spp. is reinstated instead of E. pisi var. cruchetiana. Ten species, viz., E. astragali, E. bremeri, E. caulicola, E. cruchetiana, E. iranica, E. medicaginis, E. pisi, E. rayssiae, E. sesbaniae and E. trifoliorum were confirmed for Iran, redescribed and illustrated on the basis of Iranian collections. Erysiphe astragali, E. bremeri, E. coluteae and E. crispula form a genetically little differentiated clade in ITS/LSU analyses, which is referred to as E. astragali clade (complex), comparable to the E. trifoliorum clade (complex). Based on our results, E. coluteae and E. crispula are reduced to synonymy with E. astragali and E. sophorae is considered a synonym of E. bremeri. Sequences of the North American E. intermedia on Lupinus species form a small clade nested within the big E. astragali clade. DNA of the holotype of E. sesbaniae was sequenced for the first time in this study. To use the sequences obtained from some new collections as reference sequences for phylogenetic-taxonomic purposes, we propose, for the interim, reference sequences for E. bremeri, E. caulicola, E. cruchetiana, E. pisi and E. viciae-unijugae. [ABSTRACT FROM AUTHOR]

Powdery mildews on oaks, caused by Erysiphe species, have serious ecological consequences on a range of Quercus hosts. In addition to Erysiphe quercicola, E. alphitoides is one of the most common and widespread species of Erysiphe having a wide host range among oak species, and a clear economic significance in applied ecology, forestry, and forest pathology. There are many publications addressing these important tree pathogens. Previous phylogenetic examinations have shown that E. alphitoides refers to a complicated species assemblage with insufficient taxonomic resolution in ITS + 28S analyses; the associated sequences form an insufficiently resolved species complex. The majority of species within the E. alphitoides complex cannot be unequivocally identified based solely on ITS + 28S analyses. Most of the additional species of the E. alphitoides complex are distributed in Asia, with a concentration in Japan. The question posed is whether there is a single widespread powdery mildew species, E. alphitoides, or an assemblage of closely allied species. To answer this question, specimens of related recognized species, particularly those from Japan, have been subjected to phylogenetic multilocus examinations, including CAM, GAPDH, GS, ITS + 28S, RPB2, and TUB sequences. An analysis of the concatenated sequences resulted in the confirmation of several distinct species. These species form highly supported clades that include E. alphitoides, E. aucubae, E. euonymicola, E. ipomoeae, E. menispermi var. dahurica, E. orixae, E. pseudolonicerae, E. sinomenii and E. wallrothii. Erysiphe akebiae as well as the relationship between Japanese and North American collections requires further examinations. [ABSTRACT FROM AUTHOR]

In late summer 2022 and 2023, powdery mildew symptoms were found on female plants of hemp (Cannabis sativa) growing in a private garden in Hradec nad Moravicí (Silesia, Czech Republic). On the upper sides of the leaves, white powdery colonies were observed which coalesced and finally covered the whole leaf surface. The stems and flowers were not affected. Microscopic examination revealed the formation of asexual (anamorphic) states characterized by conidiophores forming catenescent conidia (Euoidium type), but with two types of conidia, viz., ellipsoid to ovoid or doliiform conidia with fibrosin bodies (resembling conidia of Podosphaera spp.), and ellipsoid to doliiform conidia without fibrosin bodies (resembling conidia of Golovinomyces spp.). Molecular genetic analyses confirmed co‐infections in the studied hemp samples by two powdery mildew species, viz., Podosphaera macularis and Golovinomyces ambrosiae, which represent first records from the Czech Republic, as well as Europe and in the world. The authors discuss the latest information and ideas regarding this pathosystem. [ABSTRACT FROM AUTHOR]

In this contribution, we offer the fifth installment of a series focusing on the phylogeny and taxonomy of powdery mildews. This paper is the second segment evaluating the genus Erysiphe. The first treatment of Erysiphe focused on phylogenetically basal species in the "Uncinula lineage." This research presents a phylogenetic-taxonomic assessment of species that form the group previously referred to as the "Microsphaera lineage." Given the size of the group, we split the treatment of this lineage of Erysiphe species into two parts based on their phylogenetic placement. Phylogenetic trees based on ITS+28S data are supplemented by sequences of additional markers (CAM, GADPH, GS, RPB2, and TUB). Included in the analysis of the Microsphaera lineage is the "Erysiphe aquilegiae complex" (group, clade, cluster), which encompasses sequences obtained from an assemblage of Erysiphe species with insufficient resolution in rDNA analyses. Attempts have been made to resolve this group at the species level by applying a multilocus approach. A detailed discussion of the "Erysiphe aquilegiae complex" is provided. Sequences are provided for the first time for several species, particularly North American species, such as Erysiphe aggregata, E. erineophila, E. parnassiae, and E. semitosta. Ex-type sequences for Microsphaera benzoin and M. magnusii have been retrieved. Alphitomorpha penicillata, Microsphaera vanbruntiana, and M. symphoricarpi are epitypified with ex-epitype sequences. The new species Erysiphe alnicola, E. deutziana, E. cornigena, E. lentaginis, and E. sambucina are described, the new combinations E. lauracearum, E. passiflorae, and E. sambucicola are introduced, and the new name E. santali is proposed. [ABSTRACT FROM AUTHOR]

This is the fourth contribution within an ongoing series dedicated to the phylogeny and taxonomy of powdery mildews. This particular installment undertakes a comprehensive evaluation of a group previously referred to as the "Uncinula lineage" within Erysiphe. The genus Erysiphe is too large to be assessed in a single paper; thus, the treatment of Erysiphe is split into three parts, according to phylogenetic lineages. The first paper, presented here, discusses the most basal lineage of Erysiphe and its relationship to allied basal genera within tribe Erysipheae (i.e., Brasiliomyces and Salmonomyces). ITS+28S analyses are insufficient to resolve the basal assemblage of taxa within the Erysipheae. Therefore, phylogenetic multilocus examinations have been carried out to better understand the evolution of these taxa. The results of our analyses favor maintaining Brasiliomyces, Bulbomicroidium, and Salmonomyces as separate genera, at least for the interim, until further phylogenetic multilocus data are available for additional basal taxa within the Erysipheae. The current analyses also confirmed previous results that showed that the "Uncinula lineage" is not exclusively composed of Erysiphe species of sect. Uncinula but also includes some species that morphologically align with sect. Erysiphe, as well as species that had previously been assigned to Californiomyces and Typhulochaeta. Numerous sequences of Erysiphe species from the "Uncinula lineage" have been included in the present phylogenetic analyses and were confirmed by their position in well-supported species clades. Several species have been sequenced for the first time, including Erysiphe clintonii, E. couchii, E. geniculata, E. macrospora, and E. parvula. Ex-type sequences are provided for 16 taxa including E. nothofagi, E. trinae, and E. variabilis. Epitypes are designated and ex-epitype sequences are added for 18 taxa including Erysiphe carpophila, E. densa, and U. geniculata var. carpinicola. The new species Erysiphe canariensis is described, and the new names E. hosagoudarii and E. pseudoprunastri and the new combination E. ampelopsidis are introduced. [ABSTRACT FROM AUTHOR]

Sweet cherry is a high-value fresh market crop whose commercial value is directly related to fruit quality. Morphological studies and phylogenetic analyses have shown that a distinct powdery mildew species, Podosphaera cerasi, infects sweet cherry in orchards, nurseries, and greenhouses for stock production. The fungal species P. clandestina, which was thought to cause powdery mildew infection in sweet cherry, is now confined to the powdery mildew that infects Crataegus spp. The intricate nomenclatural-taxonomic history of sweet cherry powdery mildew is briefly outlined. This review has been written to serve production managers as well as applied and basic research regarding control of this pathogen. The economic impact of this powdery mildew, environmental aspects contributing to its epidemiology, management options including both conventional chemical and biopesticide products, as well as mycoviruses associated with P. cerasi are discussed. Additionally, an overview of host–pathogen resistance based on cultivar, fungicide resistance, the role of chasmothecia in epidemic initiation, and susceptible stages of fruit to infection are discussed. [ABSTRACT FROM AUTHOR]

This contribution is part of a series devoted to the phylogeny and taxonomy of powdery mildews, with an emphasis on North American taxa. An overview of Cystotheca species is given, including references to ex-type sequences or, if unavailable, proposals for representative reference sequences for phylogenetic-taxonomic purposes. The new species C. mexicana is described, based on Mexican collections on Quercus glaucoides × Quercus microphylla and Quercus liebmannii × Q. microphylla. Cystotheca lanestris is reported for the first time worldwide on Quercus laceyi (Collected in Mexico) and on Q. toumeyi (collected in Arizona, USA). Cystotheca lanestris on Q. agrifolia and on Q. cerris is reported for the first time in Mexico. Epitypes with ex-epitype sequences are designated for Cystotheca wrightii, Lanomyces tjibodensis (= C. tjibodensis), Sphaerotheca kusanoi, and S. lanestris (C. lanestris). [ABSTRACT FROM AUTHOR]

The second contribution to a new series devoted to the phylogeny and taxonomy of powdery mildews is presented. An overview of Neoerysiphe species is given, including references to ex-type sequences or, if unavailable, representative reference sequences for phylogenetic-taxonomic purposes are provided. The new species N. stachydis is described, and Striatoidium jaborosae is reduced to synonymy with Neoerysiphe macquii. Epitypes with ex-epitype sequences are designated for Alphitomorpha ballotae, A. labiatarum, Erysiphe galii, E. chelones, and E. galeopsidis. Based on phylogenetic analyses, it has been demonstrated that Neoerysiphe cumminsiana is confined to its type host, Roldana hartwegii (= Senecio seemannii), and other North and South American parasites on Asteraceae hosts, previously assigned to this species, pertain to N. macquii. The first record of N. macquii from Europe (Germany) on cultivated Bidens aurea was confirmed by sequencing. Sequence analysis of type material of N. rubiae reveals that this species should be excluded from Neoerysiphe; however, the true affinity of this taxon is not yet clear. [ABSTRACT FROM AUTHOR]

Powdery mildews are a monophyletic group of obligate plant pathogenic fungi in the family Erysiphaceae. Powdery mildews are economically important in that they cause damage to many agriculturally significant crops and plants in ecologically important habitats. In this contribution, we introduce a new series of publications focusing on the phylogeny and taxonomy of this group, with an emphasis on specimens collected from North America. The first part of the series focuses on the genus Golovinomyces and includes a section detailing the powdery mildew species concept. We conducted analyses of Golovinomyces spp. with available rDNA sequence data from GenBank and supplemented the data set with rDNA (ITS, 28S, IGS) as well as protein-coding (GAPDH) data from 94 North American collections. Many of the species evaluated are included in phylogenetic and morphological analyses for the first time, including the American species G. americanus, G. brunneopunctatus, G. californicus, G. greeneanus, G. hydrophyllacearum, and G. sparsus. A special emphasis was placed on acquiring ex-type or ex-epitype sequences or presenting reference sequences for phylogenetic-taxonomic purposes. Three new species, G. eurybiarum, G. galiorum, and G. malvacearum, are described, and the new combinations G. fuegianus, G. mutisiae, and G. reginae are introduced. Ex-holotype sequences of Erysiphe sparsa (≡ G. sparsus) reveal that it should be reduced to synonymy with G. ambrosiae, and ex-epitype sequences of G. valerianae reveal that it should be reduced to synonymy with G. orontii. Multiple epitypes are designated with ex-epitype sequences. [ABSTRACT FROM AUTHOR]

In March 2021, severe signs of powdery mildew were observed on leaves and stems of Coccinia grandis in the Manchar, Pune District, Maharashtra state, India. Based on morphological examination, phylogenetic analyses, and pathogenicity test, the causal agent of powdery mildew on Coccinia grandis was identified as Golovinomyces tabaci. To our knowledge, this is the first record of G. tabaci infecting C. grandis in India. Previously, G. tabaci had only been reported on C. grandis from Taiwan and Thailand. [ABSTRACT FROM AUTHOR]

The genus Rhododendron comprises over 1000 evergreen and deciduous species. In the Pacific Northwest Coast region of North America (PNWC), powdery mildews infecting deciduous Rhododendron spp. are well documented but less so on evergreen Rhododendron spp. Infections of both groups of hosts historically have been attributed to Erysiphe azaleae or E. vaccinii. No formal characterizations of powdery mildew fungi infecting either deciduous or evergreen Rhododendron spp. in the PNWC have been completed. The objectives of this study were to identify the powdery mildew pathogens infecting evergreen Rhododendron spp. in the PNWC and to assess the phylogenetic position of these fungi within the Erysiphaceae. To ascertain valid taxonomic conclusions, and to determine whether potential introductions of exotic Rhododendron powdery mildews in North America have occurred, it was necessary to put the new North American phylogenetic data into a worldwide context. Therefore, available phylogenetic data from all Erysiphe spp. on Rhododendron have been included in our analyses. Based on analyses of numerous new internal transcribed spacer (ITS) and 28S rDNA sequences and already available sequences deposited in GenBank retrieved from evergreen and deciduous Rhododendron spp., the following Erysiphe spp. could be phylogenetically confirmed (all belonging to Erysiphe sect. Microsphaera): Erysiphe azaleae nom. cons. (Oidium ericinum could be verified as a synonym), E. digitata (holotype sequenced), E. izuensis, and E. vaccinii. Erysiphe azaleae and E. vaccinii are epitypified with sequenced specimens, and an ex-neotype sequence has been obtained for Oidium ericinum. Erysiphe rhododendri (Erysiphe sect. Erysiphe), only known from two collections in India (Himalayan region), was not available for phylogentic analyses. [ABSTRACT FROM AUTHOR]

Phylogenetic and morphological analyses have been conducted on powdery mildew specimens on different Berberis and Mahonia spp. from Asia, Europe and North America. The present study showed that collections of Erysiphe berberidis exhibit a high degree of morphological plasticity of the sexual morph, in contrast to their morphologically, rather uniform, asexual morph. In phylogenetic tree, all sequences cluster in a large strongly supported clade, without any indication and support for further differentiation into cryptic species. There are three morphological types within E. berberidis s. lat. that contain consistent differences. Until future multi-locus analyses will be available, we prefer to treat these 'morphological types' as varieties. These include Erysiphe berberidis var. berberidis, E. berberidis var. asiatica, and E. berberidis var. dimorpha comb. nov. (≡ Microsphaera berberidis var. dimorpha, M. berberidicola, and M. multappendicis). To fix the application of species name E. berberidis, an appropriate epitype was designated, with an ITS sequences. [ABSTRACT FROM AUTHOR]

Maples (Acer spp., Sapindaceae) are one of the most important and dominant groups of trees in Hyrcanian forests of Iran. During our survey of leaf-inhabiting fungi associated with trees in Hyrcanian forests, several hyphomycetous fungal strains were recovered from leaf spot symptoms of maple trees. The identification of these isolates was performed using phylogenetic analyses coupled with morphological observations. Based on these data, two new genera of the Dothideomycetes were discovered. Acericercospora gen. nov. (Mycosphaerellaceae) is introduced to accommodate Acericercospora hyrcanica sp. nov. associated with leaf lesions on Acer cappadocicum and A. velutinum. Paramycocentrospora gen. nov. (Dothidotthiaceae) with Paramycocentrospora acericola sp. nov. as type species, is associated with leaf lesions on seedlings of A. velutinum. In this paper, detailed descriptions and illustrations are provided for the new taxa, supplemented by comprehensive comparisons with allied and similar taxa. [ABSTRACT FROM AUTHOR]

Using molecular phylogenetic analyses (ITS) and morphological data obtained from light and electron microscopy, some European and North American species and genera placed or formerly placed in the genus Pucciniastrum in the Coleosporiaceae and Pucciniastraceae (Pucciniales) were taxonomically revised. The ITS analyses confirmed recent familiar concepts based on less variable markers except for the genus Hyalopsora. The family Pucciniastraceae is characterized by Abietoideae (Abies, Tsuga) aecial hosts. Pucciniastrum is described as a genus that consists of host-alternating species forming aecia on needles of Abies hosts, with special features of aeciospore morphology, and Onagraceae telial hosts. Other genera in the Pucciniastraceae are Calyptospora, Melampsorella, and additional taxa, which are currently provisionally placed in Pucciniastrum, but must be revised in future studies. Pucciniastrum epilobii (s. lat.), the type species of Pucciniastraceae, represents at least two species with different life cycles and urediniospore characteristics and is lecto- and epitypified. The family Coleosporiaceae, characterized by Pinoideae (Pinus) and Piceoideae (Picea) aecial hosts, contains Rosaceae rusts from three well-supported clades represented by three genera, Thekopsora, Quasipucciniastrum, and Aculeastrum gen. nov. Aculeastrum is characterized by coarsely arcuate ostiolar peridial cells and infects Rubus spp. telial hosts. The following new taxonomic combinations are proposed: Calyptospora ornamentalis comb. nov., Quasipucciniastrum ochraceum comb. nov., Q. potentillae comb. nov, Aculeastrum americanum comb. nov., and A. arcticum comb. nov. The results are discussed with emphasis on future studies in Pucciniastrum and the P. epilobii complex and on nomenclatural changes necessary for rust fungi due to the Shenzhen Code. [ABSTRACT FROM AUTHOR]

Powdery mildew fungi (Erysiphaceae), common obligate biotrophic pathogens of many plants, including important agricultural and horticultural crops, represent a monophyletic lineage within the Ascomycota. Within the Erysiphaceae , molecular phylogenetic relationships and DNA-based species and genera delimitations were up to now mostly based on nuclear ribosomal DNA (nrDNA) phylogenies. This is the first comprehensive genome-scale phylogenetic analysis of this group using 751 single-copy orthologous sequences extracted from 24 selected powdery mildew genomes and 14 additional genomes from Helotiales , the fungal order that includes the Erysiphaceae. Representative genomes of all powdery mildew species with publicly available whole-genome sequencing (WGS) data that were of sufficient quality were included in the analyses. The 24 powdery mildew genomes included in the analysis represented 17 species belonging to eight out of 19 genera recognized within the Erysiphaceae. The epiphytic genera, all but one represented by multiple genomes, belonged each to distinct, well-supported lineages. Three hemiendophytic genera, each represented by a single genome, together formed the hemiendophytic lineage. Out of the 14 other taxa from the Helotiales , Arachnopeziza araneosa , a saprobic species, was the only taxon that grouped together with the 24 genome-sequenced powdery mildew fungi in a monophyletic clade. The close phylogenetic relationship between the Erysiphaceae and Arachnopeziza was revealed earlier by a phylogenomic study of the Leotiomycetes. Further analyses of powdery mildew and Arachnopeziza genomes may discover signatures of the evolutionary processes that have led to obligate biotrophy from a saprobic way of life. A separate phylogeny was produced using the 18S, 5.8S, and 28S nrDNA sequences of the same set of powdery mildew specimens and compared to the genome-scale phylogeny. The nrDNA phylogeny was largely congruent to the phylogeny produced using 751 orthologs. This part of the study has revealed multiple contamination and other quality issues in some powdery mildew genomes. We recommend that the presence of 28S, internal transcribed spacer (ITS), and 18S nrDNA sequences in powdery mildew WGS datasets that are identical to those determined by Sanger sequencing should be used to assess the quality of assemblies, in addition to the commonly used Benchmarking Universal Single-Copy Orthologs (BUSCO) values. [ABSTRACT FROM AUTHOR]

Powdery mildew on oak, caused by Erysiphe spp., has been shown to have serious ecological consequences on a range of Quercus hosts. Erysiphe alphitoides and E. quercicola are two of the most heavily studied and common powdery mildews known to occur on Quercus species. In recent years, these species have been noted throughout the world on a range of hosts within and outside the Quercus genus. Reports that E. alphitoides was absent in European herbaria before 1921 and the discovery of the holotype of E. alphitoides from 1911 in an American herbarium (FH) led to the current study in which we genetically analysed six specimens of E. alphitoides s. lat including, most importantly, the holotype of E. alphitoides from France collected in 1911. The results of our analyses revealed that: (1) The sequence of the E. alphitoides holotype falls within the E. quercicola clade, confirming that E. alphitoides did not spread to Europe until ~1921. (2) E. alphitoides var. chenii forms a monophyletic clade with E. epigena and should be reduced to synonymy with that species and (3) through sequence analyses E. alphitoides and E. quercicola are confirmed to have spread to North America. The sequencing results of the E. alphitoides holotype have severe nomenclatural‐taxonomic consequences. A proposal was submitted simultaneously with the present manuscript to conserve the name E. alphitoides so that the traditional usage of the names E. alphitoides and E. quercicola could be maintained. The sequences obtained for the current study provide new insight into the taxonomy and spread of these ecologically significant, globally distributed species. The present study highlights the importance of sequencing specimens from type material, above all when morphological similar species are involved. [ABSTRACT FROM AUTHOR]

Recently performed phylogenetic-taxonomic analyses of species belonging to Erysiphe sect. Uncinula on willows (Salix spp.) demonstrated a much higher diversity than previously assumed. Phylogenetic analyses and morphological examinations of Chinese Erysiphe collections on Salix abscondita (= S. raddeana), S. sinica and S. taraikensis, all belonging to Salix subgen. Vetrix sect. Vetrix, revealed an additional cryptic species which is described as Erysiphe salicina. The new species is morphologically and phylogenetically distinguished from all other powdery mildew species. The phylogeny of the new species and closely related species on Populus and Salix spp. (Salicaceae) was reconstructed and discussed using a combined alignment of the internal transcribed spacer (ITS) regions and partial 28S rDNA sequences. The present phylogenetic analyses suggest that the recently described E. salicicola (on Salix gracilistyla in Republic of Korea) has to be reduced to synonymy with E. salicis-gracilistylae comb. nov. (≡ Uncinula salicis-gracilistylae). [ABSTRACT FROM AUTHOR]

In December 2020, Euphorbia leucocephala plants exhibiting symptoms of powdery mildew were observed in the Botanical Garden of Tuljaram Chaturchand College, Baramati, Maharashtra, India. Based on morphological identification, DNA sequence analysis, and pathogenicity, the fungal pathogen of the disease was identified as Leveillula clavata. This is the first report of L. clavata on Euphorbia leucocephala from India and in general. [ABSTRACT FROM AUTHOR]

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The genus Lupinus (Fabaceae) consists of over 250 plant species located throughout the world. Powdery mildew, caused by Erysiphe species, is a common disease infecting these ecologically, ornamentally, and agriculturally important plants. In the present work, we conducted phylogenetic and taxonomic analyses on Erysiphe species colonizing hosts of the leguminous genus Lupinus, using sequences from the internal transcribed spacer (ITS) and 28S genomic regions. Powdery mildews of the genus Erysiphe on Fabaceae are taxonomically intricate and challenging. Therefore, it is necessary to phylogenetically analyze the DNA retrieved from powdery mildew on lupines in a broad context that includes common and allied powdery mildew species that occur on a range of leguminous plants such as Erysiphe astragali, E. baeumleri, E. pisi, and E. trifoliorum. A new species Erysiphe lupini, found in the USA on Lupinus lepidus, L. polyphyllus, and Lupinus sp., is described. Additionally, Erysiphe intermedia (≡ Microsphaera trifolii var. intermedia) has been confirmed as a North American lupine powdery mildew that is a sister species to E. astragali on Astragalus spp. European Erysiphe collections on lupines were often referred to as E. intermedia, but our analyses have shown that they pertain to E. trifoliorum. The E. trifoliorum clade is composed of several species (i.e. E. baeumleri, E. euonymi, E. hyperici, and E. trifoliorum), that cannot be sufficiently resolved based solely on ITS+28S sequences. Morphological and biological differences between the species are discussed and provide evidence that the species concerned should be maintained. Finally, a sequence obtained from a powdery mildew collected in Portugal on the native Lupinus micranthus pertained to the Erysiphe guarinonii clade. This collection is tentatively treated as Erysiphe sp. To fix the application of the species names E. astragali, E. baeumleri (including its synonym E. marchica), and E. intermedia, epitypes have been designated with ex-epitype sequences. [ABSTRACT FROM AUTHOR]

The phylogeny and taxonomy of Podosphaera filipendulae (including P. filipendulensis, syn. nov.) have been examined. Asian, European and North American collections were examined and the nucleotides sequences of their partial rDNA region were determined. In particular, the relationship between P. filipendulae and P. spiraeae was analysed. The results confirmed P. filipendulae and P. spiraeae as two separate, morphologically similar species. The phylogenetic analysis revealed a similar phylogeny to that of the host genera. Although ITS sequences retrieved from Asian, European and North American specimens of P. filipendulae on various Filipendula spp. are identical to sequences from P. macularis on hop, there is consistently one base substitution at the 5'-end of 28S rRNA gene between the species. This result provides evidence that the hop powdery mildew and P. filipendulae are biologically and morphologically clearly distinguished, and should be maintained as two separate species. [ABSTRACT FROM AUTHOR]

Species of Passalora s. lat. are phytopathogenic fungi that generally cause leaf spot diseases on a broad variety of plants throughout the world. During our investigations exploring cercosporoid fungi associated with leaf spot symptoms of fruit and forest trees in northern and north-western Iran, several passalora-like fungi were isolated from symptomatic leaves of trees belonging to the Fabaceae, Malvaceae, Rosaceae, and Ulmaceae. A polyphasic taxonomic approach applying molecular data, morphological features, and host data was employed to identify the isolates. In a multi-gene phylogenetic analysis (LSU, ITS, and RPB2), these isolates are clustered in four clades in the Mycosphaerellaceae. The taxa encompassed Paracercosporidium microsorum on Tilia platyphyllos, Prathigadoides gleditsiae-caspicae gen. et. sp. nov. on Gleditsia caspica, Pruniphilomyces circumscissus on Prunus avium and Prunus cerasus, and Sirosporium celtidis on Celtis australis. The new genus Prathigadoides and its type species Prathigadoides gleditsiae-caspicae are molecularly distinct from all phylogenetically related genera, and some characteristics of the conidiophores and conidia differ from those of the morphologically similar species Prathigada condensata on the North America Gleditsia triacanthos. [ABSTRACT FROM AUTHOR]

A taxonomic revision of the hitherto monotypic genus Blumeria was conducted incorporating multi-gene sequence analyses, host preference data and morphological criteria. The sequenced loci included rDNA ITS, partial chitin synthase gene (CHS1), as well as fragments of two unnamed orthologous genes (Bgt-1929, Bgt-4572). The combined evidence led to a reassessment and a new neotypification of B. graminis s. str. (emend.), and the description of seven additional species, viz. B. americana sp. nov. (mainly on hosts of the Triticeae), B. avenae sp. nov. (on Avena spp.), B. bromi-cathartici sp. nov. (on Bromus catharticus), B. bulbigera comb. nov. (on Bromus spp.), B. dactylidis sp. nov. (on Dactylis glomerata as the main host, but also on various other hosts), B. graminicola sp. nov. (on Poa spp. as principal hosts, but also on various other hosts), and B. hordei sp. nov. (on Hordeum spp.). Synonyms were assessed, some were lectotypified, and questionable names previously associated with powdery mildew on monocots were discussed although their identities remained unresolved. Keys to the described species were developed. [ABSTRACT FROM AUTHOR]

Fungal pathogens have the potential to affect plant biogeography and ecosystem processes through their influence on the fitness and functioning of their plant hosts. Simultaneously, changes in plant communities can influence fungal pathogen communities. Exactly which host plant attributes determine the composition of fungal pathogen communities on the leaves remains poorly understood.Here, we characterized foliar fungal pathogen communities in subtropical tree communities along an experimental diversity gradient in Jiangxi, South‐East China. On 32 tree species, we identified all visible fungal structures and symptoms microscopically and studied fungi‐specific traits such as conidia or spores in detail. We asked how different facets of biodiversity, including taxonomic, phylogenetic and functional tree diversity, shape fungal diversity and fungal infestation at different scales.We found a positive relationship between tree richness and fungal richness at the plot level. At the level of individual trees of the same species, the relationship between tree species richness and fungal species richness was marginally significantly negative. Importantly, the fungal infestation rates decreased as tree species richness increased, suggesting that colonization of hosts by specialist fungi was impeded by dilution of the pool of available hosts. Moreover, we found evidence for similar topologies between phylogenetic topologies of trees and fungal genera which is a precondition for coevolution and we identified leaf traits, including leaf habit (deciduous/evergreen), leaf magnesium content and stomata size that predicted fungal richness and infestation.Synthesis. Our study indicates that host tree species harbour different foliar fungal pathogens, which sums up to the highest fungal pathogen richness in more diverse forest stands. At the same time, the foliar fungal pathogen infestation rate for each tree species decreased with increasing tree richness in forests. We identified leaf traits that can help to better predict fungal pathogen richness and infestation, and we show that phylogenetically closely related tree species harbour phylogenetically closely related foliar fungal pathogens. These new insights might be helpful to improve the pest resilience of future forests and plantations. [ABSTRACT FROM AUTHOR]

Erysiphe adunca s. lat. is a common powdery mildew species, distributed almost worldwide, on hosts of Populus and Salix species. Based on its wide host range and distribution as well as its strong morphological variations, E. adunca s. lat. was previously divided into several species or, alternatively, into varieties. However, comprehensive phylogenetic examinations on the putative monophyly of this species or the existence of a possible E. adunca species complex have not been conducted based on combined morphological and molecular approaches. In this study, we retrieved rDNA (ITS and LSU) sequences of 22 powdery mildew specimens on Populus and Salix spp. collected in China, Germany, Iran, Japan, Russia, and the United States and conducted morphological examinations of these and additional specimens. The morphological and molecular data obtained clearly indicate that E. adunca is a species complex comprised of at least four species., viz., E. adunca s. str. (on Populus spp. in Asia, Europe, and North America), E. capreae, including E. pseudoregularis as a new synonym (on Salix spp., particularly on species in Salix subgen. Vetrix sect. Vetrix in Asia, Europe, and North America), the reinstated E. salicis (on Salix spp. belonging to various subgenera of Salix in Asia and Europe), and E. mandshurica (which has been confirmed as a species of its own on Populus spp., in Asia). In addition to the clear phylogenetic differentiation, the morphology of the asexual and sexual morphs of E. adunca s. str., E. capreae and E. salicis is easily distinguishable. Sequences retrieved from collections on Salix gracilistyla (Uncinula salicis-gracilistylae), a species that was previously considered a variety of Uncinula adunca and Erysiphe adunca, formed a small subclade within the E. salicis clade and are now referred to as Erysiphe salicis var. salicis-gracilistylae comb. nov. Alphitomorpha adunca; Erysiphe capreae and E. salicis are epitypified, and a neotype is designated for Alphitomorpha obtusata, with ex-epitype sequences and, in the latter case, an ex-neotype sequence. [ABSTRACT FROM AUTHOR]

Leaf fungal pathogens alter their host species’ performance and, thus, changes in fungal species composition can translate into effects at the tree community scale. Conversely, the functional diversity of tree species in a host tree’s local neighbourhood can affect the host’s foliar fungal infestation. Therefore, understanding the factors that affect fungal infestations is important to advance our understanding of biodiversity-ecosystem functioning (BEF) relationships. Here we make use of the largest BEF tree experiment worldwide, the BEF-China experiment, where we selected tree host species with different neighbour species. Identifying fungal taxa by microscopy and by high-throughput DNA sequencing techniques based on the internal transcribed spacer (ITS) rDNA region, we analysed the fungal richness and infestation rates of our target trees as a function of local species richness. Based on the visual microscopic assessment, we found that a higher tree diversity reduced fungal richness and host-specific fungal infestation in the host’s local neighbourhood, while molecular fungal richness was unaffected. This diversity effect was mainly explained by the decrease in host proportion. Thus, the dilution of host species in the local neighbourhood was the primary mechanism in reducing the fungal disease severity. Overall, our study suggests that diverse forests will suffer less from foliar fungal diseases compared to those with lower diversity. View Full-Text [ABSTRACT FROM AUTHOR]

Erysiphe species (powdery mildews) on Corylus and Ostrya hosts (Betulaceae subfam. Coryloideae) in Asia and North America are widespread pathogens on these economically and ecologically valuable nut crops. An improved understanding of their phylogeny and taxonomy is of ecological and applied importance. Phylogenetic analyses and morphological reexaminations conducted in this study revealed a higher degree of diversity and cryptic speciation than reflected in earlier species concepts. North American collections on C. cornuta, which were previously assigned to E. corylacearum, proved to constitute a species of its own and are herein introduced as E. cornutae, sp. nov. Two additional North American species, E. coryli-americanae, sp. nov. and E. ostryae, sp. nov., have been detected on C. americana and O. virginiana and are described. They are morphologically similar to E. cornutae, but genetically distinct. Based on phylogenetic analyses, E. corylacearum is an Asian species confined to various Asian Corylus species. Sequence data retrieved from Japanese type material of E. corylicola revealed that this species clusters with sequences from E. elevata on Catalpa species, distant from all other Erysiphe species on Corylus. Morphologically similar, yet distinct, specimens on C. sieboldiana, which were previously assigned to E. corylicola, form a distinct, distant clade. The species involved is described herein as E. pseudocorylacearum, sp. nov. Additionally, an unusual infection of C. sieboldiana in Japan by E. syringae has been shown by means of sequence data. The phylogeny and taxonomy of Erysiphe species belonging to the Corylioideae are discussed in detail, and a key to the species concerned is provided. [ABSTRACT FROM AUTHOR]

Digitopodium hemileiae was described originally in 1930 as Cladosporium hemileiae; growing as a mycoparasite of the coffee leaf rust (CLR), Hemileia vastatrix, in a sample of diseased leaves of Coffea canephora collected in the Democratic Republic of Congo. No cultures from this material exist. More recently, the type material was reexamined and, based on morphological features, considered to be incorrectly placed in Cladosporium. The new genus Digitopodium was erected to accommodate this species. Interest in fungal antagonists of H. vastarix, as potential biocontrol agents of CLR, led to comprehensive surveys for mycoparasites, both in the African centre of origin of the rust, as well as in its South American exotic range. Among the rust specimens from Ethiopia, one was found to be colonized by a fungus congeneric with, and similar to, D. hemileiae. Pure cultures obtained from the Ethiopian material enabled a molecular study and for its phylogenetic position to be elucidated, based on DNA sequence data from the ITS and LSU regions. Molecular data showed that two members of the recently erected genus Hyalocladosporiella (Herpotrichiellaceae: Chaetothyriales) are congeneric with Digitopodium from Ethiopia and morphologically similar to both D. hemileiae and the two Ethiopian isolates. These isolates were found to be morphologically and genetically identical to H. tectonae, described previously from Brazil. Thus, species of Hyalocladosporiella are re-allocated to Digitopodium here; including D. tectonae, and a novel species, D. canescens, recently found in Brazil growing as a mycoparasite of Puccinia thaliae. The potential use of D. hemileiae and D. tectonae for classical biological control of CLR is discussed. [ABSTRACT FROM AUTHOR]

Erysiphe bulbouncinula (≡ Bulbouncinula bulbosa) on Koelreuteria paniculata is a powdery mildew native and endemic in China. Fresh samples of this species were collected on K. paniculata in Sichuan Province, China, in 2018. This is the fourth confirmed identification of this species. The original description in 1932 was based on one specimen from Hangzhou and then was described in Nanjing in 1990 and in Taiwan in 1993. The morphology of the new collections of this species is described and illustrated in detail, and agrees well with the original description of the type specimen except for the number of asci (8–16 asci per chasmothecia versus 7–9 asci in the type specimen). To explore the phylogenetic position of this poorly known species, three separate phylogenetic analyses, using partial 28S rDNA and the combination of internal transcribed spacer (ITS) and 28S rDNA sequences, were conducted. The results clearly showed that E. bulbouncinula form a monophyletic clade with strong bootstrap (BS) support (MP = 100%) constituting a sister clade to E. gracilis s. lat., form a subclade with Erysiphe sect. Californiomyces and then form a big group with sect. Typhulochaeta and sect. Uncinula. Phylogenetic results confirm that E. bulbouncinula is more closely allied to Erysiphe than to Phyllactinia. Thus, this species can be maintained in Erysiphe in its current circumscription, confirming Bulbouncinula as a synonym of Erysiphe. [ABSTRACT FROM AUTHOR]

The phylogeny and taxonomy of powdery mildew on Viburnum species is evaluated and discussed. Morphological and phylogenetic analyses revealed two new species and demonstrated that Erysiphe hedwigii and E. viburni should be reduced to synonymy and are referred to herein as E. viburni. The two new species, E. viburniphila and E. pseudoviburni, previously hidden under E. viburni (including E. hedwigii), is described on the basis of European, North American, and East Asian powdery mildew collections on Viburnum edule, V. tinus, V. odoratissimum var. awabuki, and V. sieboldii. The sexual morph of E. viburniphila is similar to that of E. viburni; however, morphological differences exist in their asexual morphs. Analyses of sequences from the internal transcribed spacer (ITS) and 28S genomic regions of Erysiphe species obtained on Viburnum species (and other closely allied Eryisphe species) throughout the world reveled that E. viburniphila and E. pseudoviburni are in two different monophyletic groups that are separate from all other Erysiphe species. Erysiphe hedwigii and E. viburni on Viburnum species have often been recognized as separate species based on morphological differences in the size of their chasmothecia and the number of chasmothecial appendages. Taxonomic conclusions based on these morphological distinctions within these species are unreliable (these characters are rather variable and often have overlapping ranges). The present phylogenetic analyses suggest that E. hedwigii has to be reduced to synonymy with E. viburni. To fix the application of the species names E. hedwigii and E. viburni, epitypes have been designated for these taxa with ex-epitype sequences. Additionally, the Asian species E. miranda is phylogenetically confirmed as a species of its own, described in detail and discussed. [ABSTRACT FROM AUTHOR]

Background: Previous phylogenetic analyses of species within the genus Golovinomyces (Ascomycota, Erysiphales), based on ITS and 28S rDNA sequence data, revealed a co-evolutionary relationship between powdery mildew species and hosts of certain tribes of the plant family Asteraceae. Golovinomyces growing on host plants belonging to the Heliantheae formed a single lineage, comprised of a morphologically differentiated complex of species, which included G. ambrosiae, G. circumfusus, and G. spadiceus. However, the lineage also encompassed sequences retrieved from Golovinomyces specimens on other Asteraceae tribes as well as other plant families, suggesting the involvement of a plurivorous species. A multilocus phylogenetic examination of this complex, using ITS, 28S, IGS (intergenic spacer), TUB2 (beta-tubulin), and CHS1 (chitin synthase I) sequence data was carried out to clarify the discrepancies between ITS and 28S rDNA sequence data and morphological differences. Furthermore, the circumscription of species and their host ranges were emended. Results: The phylogenetic and morphological analyses conducted in this study revealed three distinct species named, viz., (1) G. ambrosiae emend. (including G. spadiceus), a plurivorous species that occurs on a multitude of hosts including, Ambrosia spp., multiple species of the Heliantheae and plant species of other tribes of Asteraceae including the Asian species of Eupatorium; (2) G. latisporus comb. nov. (≡ Oidium latisporum), the closely related, but morphologically distinct species confined to hosts of the Heliantheae genera Helianthus, Zinnia, and most likely Rudbeckia; and (3) G. circumfusus confined to Eupatorium cannabinum in Europe. Conclusions: The present results provide strong evidence that the combination of multi-locus phylogeny and morphological analysis is an effective way to identify species in the genus Golovinomyces. [ABSTRACT FROM AUTHOR]

Podosphaera tridactyla (s. lat.) is a powdery mildew species occurring on a wide range of Prunus spp. almost worldwide. We have investigated the phylogeny of the Po. tridactyla complex, with special emphasis on potential aspects of cryptic speciation. The results suggested that Po. tridactyla represents a species complex consisting of at least 12 different species. Based on detailed morphological examinations and molecular sequence analyses, we propose dividing Po. tridactyla s. lat. into 10 species, encompassing 7 new species (Po. ampla, Po. pruni-avium, Po. pruni-cerasoidis, Po. prunigena, Po. pruni-lusitanicae, Po. prunina, and Po. pruni-japonicae) and 3 known species (Po. longiseta, Po. salatai, and Po. tridactyla s. str.). Oidium passerinii on Pr. laurocerasus is confirmed as a synonym of Po. tridactyla s. str. Epitypes are designated for Po. tridactyla and Oidium passerinii. [ABSTRACT FROM AUTHOR]

Recently published phylogenetic analyses of the Golovinomyces orontii complex revealed that three different species of the genus Golovinomyces may occur on cucurbitaceous hosts, viz., G. bolayi , G. orontii s. str., and G. tabaci. Owing to its morphological characteristics, Erysiphe cucurbitacearum (≡ G. cucurbitacearum) was tentatively reduced to synonym with G. tabaci. However, final conclusions on the identity and status of E. cucurbitacearum , described from China on Cucumis sativus , as putative synonym of G. tabaci required a phylogenetic confirmation and epitypification with ex-epitype sequences. Therefore, a sample of G. cucurbitacearum collected on C. sativus in Xinjiang Uygur Autonomous Region, China, in 2014 (HMJAU-PM91862) has been sequenced and is designated as epitype of the latter species, since its holotype material (HMAS 40016, collected in 1954) turned out to be too old for molecular examinations. As a result of morphological examinations and phylogenetic analyses based on ex-epitype ITS and 28S rDNA sequences, the recently assumed synonymy of G. cucurbitacearum , found on C. sativus in China, with G. tabaci could be confirmed. In addition, two new host species of G. tabaci , viz., Trigonotis peduncularis (Boraginaceae) and Rubia cordifolia (Rubiaceae), were concurrently identified. Trigonotis peduncularis is the first verified boraginaceous host for G. tabaci. • Golovinomyces found on Cucumis sativus was reallocate to as a synonymy of G. tabaci. • Additional host family and host species of G. tabaci were first found. • Phylogenetic analyses and morphology confirmed the results in this study. [ABSTRACT FROM AUTHOR]

The lichenicolous fungi growing on Graphidales hosts in Florida are revised, mainly based on collections by the second author (R. C.). Twenty-one species are recognized. The new genus and species Lawreya glyphidiphila is described for a common asexual fungus growing on Glyphis scyphulifera and more rarely Trypethelium eluteriae, characterized by black stromatic conidiomata in which subspherical conidiogenous loculi develop, producing aseptate, subglobose, brown conidia. Nine additional new species are described: Amerosporiopsis phaeographidis (on Phaeographis brasiliensis), Arthonia acanthotheciicola (onAcanthothecisfloridensis), A. subgraphidicola (on Graphis assimilis), Hemigrapha graphidicola (on G. assimilis), Skyttea graphidicola (on Graphis spp.), Strigula graphidicola (on G. assimilis), S. perparvula (on Graphidales), Talpapellis graphidis (on Graphis caesiella) and Tremella wedinii (on Glyphis scyphulifera). Phylogenetic placements of Lawreya glyphidiphila, Skyttea graphidicola and Tremella wedinii are presented. Identification keys are given for the species of Cornutispora and Talpapellis, and for the 66 species known to grow on Graphidales hosts worldwide. [ABSTRACT FROM AUTHOR]

Powdery mildew of Prunus spp. is a significant disease in most cherry growing regions of Washington, USA. Powdery mildews on Prunus virginiana and Pr. avium were previously assigned to Podosphaera clandestina s. lat. (= Po. oxyacanthae) or Po. prunicola. In this report, we confirm the presence of two distinct Podosphaera species on these hosts. Phylogenetic analyses of nuc rDNA sequences from the internal transcribed spacer region (ITS1-5.8S-ITS2 = ITS) and 28S subunit confirmed the presence of two distinct species. A morphological comparison with type material of Po. prunicola and additional collections demonstrated that the powdery mildew on Pr. virginiana (including var. demissa and var. melanocarpa) is in fact Po. prunicola. The powdery mildew on Pr. avium is genetically, morphologically, and biologically distinct from Po. prunicola and is described here as the new species Po. cerasi. Cross-inoculation experiments confirmed that these two species are host specific. Podosphaera prunicola was unable to colonize Pr. avium, whereas Po. cerasi was unable to colonize Pr. virginiana. Morphological reexamination of numerous specimens identified as Po. prunicola on a broad range of Prunus species suggests that Po. prunicola is probably confined to species in Prunus subgen.Padus (= Prunus subgen. Cerasus sect. Laurocerasus, including sect. Padus), with Pr. virginiana as the principal host. Podosphaera cerasi occurs on hosts in Prunus subgen. Cerasus, and our work confirms a newly described species of powdery mildew on Pr. avium. This work also includes the first documented and genetically proven European record of Po. prunicola on Pr. serotina and its widespread occurrence in the United States. [ABSTRACT FROM AUTHOR]

A powdery mildew (Erysiphales) has recently been collected on leaves of an ornamental shrub Deutzia parviflora in Baihua Mountain, Beijing, China. Microscopic examination of the chasmothecia suggested a species belonging to Erysiphe sect. Erysiphe, above all due to mycelioid chasmothecial appendages, although circinate apices of the appendages were rather in favour of Erysiphe sect. Uncinula, which is a fairly rare combination of appendage characteristics in Erysiphe. Phylogenetic analyses of ITS and 28S rDNA sequences demonstrated that the two examined powdery mildew collections on D. parviflora clustered together as an independent lineage within Erysiphe with 100% bootstrap support, representing a species of its own, which is phylogenetically allied to, but clearly distinct from Erysiphe deutziae and, in addition, morphologically quite different from all known Erysiphe species on hosts belonging to the Hydrangeaceae. The new species on D. parviflora is described as Erysiphe deutziicola. [ABSTRACT FROM AUTHOR]

Collections of Pseudoidium pedaliacearum on Sesamum indicum from Japan, Korea, and Nepal have been morphologically examined and subjected to molecular sequence analyses in order to clarify the taxonomic status and phylogenetic affinity of this powdery mildew. Pseudoidium pedaliacearum pertains to the Erysiphe aquilegiae clade, which encompasses several closely allied, morphologically similar powdery mildew species. The close affinity to Erysiphe sedi, Pseudoidium hortensiae (≡ Oidium hortensiae), P. neolycopersici (≡ Oidium neolycopersici), and some other taxa involved in the Erysiphe aquilegiae complex is discussed. The reexamination of P. pedaliacearum and the results of phylogenetic analyses [5′-end of the 28S rRNA gene (including the domains D1 and D2) and internal transcribed spacer (ITS) regions] led to a reassessment of this species and its reallocation to Erysiphe on the basis of the provisions of ICN Art. F.8. [ABSTRACT FROM AUTHOR]

The name Golovinomyces cynoglossi s. lat. is traditionally applied to a complex of morphologically similar powdery mildews on hosts of the plant family Boraginaceae. The current species-level taxonomy with in th is complex is ambiguous due to the lack of phylogenetic examinations . The present study applied phylogenetic methods to clarify the taxonomy of G. cynoglossi s. lat. Phylogenetic analysis of rDNA ITS sequences retrieved from Asian, European and North American specimens revealed that G. cynoglossi s. lat. collections from different hosts involved several species in five clearly separated lineages. Clade I consists primarily of Golovinomyces cynoglossis. str. on Cynoglossum. Clade III consists of Golovinomyces sequences retrieved from the host genera Symphytum and Pulmonaria. The taxa with in clade III are now assigned to G. asperifoliorum comb . nov. Clade V encompasses G. cynoglossi s. lat. on the host genera Bothriospermum, Buglossoides, Echium, Myosotis, and Trigonotis. The taxa with in clade V are now assigned to G. asperifolii comb. nov. The species concerned in this study were lecto- and epitypified to stabilize their nomenclature . [ABSTRACT FROM AUTHOR]

Ramularia ranunculicola sp. nov. (Mycosphaerellaceae) is described from Iran on Ranunculus muricatus and compared with other species reported on Ranunculus spp. Ramularia carletonii on Lactuca tuberosa and R. nagornyi on Centaurea solstitialis are newly reported from Iran, and Picris strigosa is a new host for R. picridis (= R. inaequalis s. lat.). [ABSTRACT FROM AUTHOR]

An asexual morph of a powdery mildew was found on Buddleja asiatica (Scrophulariaceae) in Nepal. The morphological traits of this powdery mildew strongly resemble those of Phyllactinia species (including Ovulariopsis ) belonging to a phylogenetically basal group closely related to Leveillula species, but phylogenetic examinations and analyses clearly showed that this fungus pertains to Leveillula . Within the latter genus, it seems to be allied to L. duriaei , but clearly differs from this species in having conidiophores arising from superficial hyphae and narrower conidia with different length/width ratios. Therefore, the powdery mildew on B. asiatica is described as Leveillula buddlejae sp. nov. [ABSTRACT FROM AUTHOR]

Since the mid-nineties Phyllactinia fraxini has become frequent in Germany. This species has hitherto been characterized by having straight conidiophore foot cells. However, we found that recent collections from Germany have conidiophores with sinuated and twisted foot cells. So far sinuated foot cells were only known from the related P. fraxinicola , another species with Eastern Asian origin. We thus hypothesized that recent collections from Germany belong to P. fraxinicola which might have been introduced to Europe. Using morphological and molecular rDNA data we found that no introduction took place and that there is only P. fraxini in Germany. [ABSTRACT FROM AUTHOR]

Cystotheca lanestris on the new host Quercus canbyi , Microidium bauhiniicola on the new host Bauhinia macranthera and an undescribed species of Phyllactinia on Mimosa aculeaticarpa have recently been collected in Mexico. Analyses of morphological traits and molecular sequence data led to identifications of the causal agents of the powdery mildew diseases involved. Microidium bauhiniicola , hitherto only known from Argentina and Brazil, is new to Mexico. The phylogenetic analysis revealed an isolated position distant from Microidium indicating an undescribed genus, which is introduced as Bulbomicroidium gen. nov. Sequences derived from a Mexican specimen of C. lanestris on Quercus canbyi agree completely with other North American sequences, but differ from sequences retrieved from Asian collections, suggesting that C. lanestris in Asia is not conspecific with C. lanestris s. str. in North America. A new species of Phyllactinia on Mimosa malacophylla is morphologically similar to P. dalbergiae but readily distinguishable by differences in the asexual morph. Based on morphological peculiarities and results of molecular sequence analyses, this species is described as Phyllactinia mimosae sp. nov. [ABSTRACT FROM AUTHOR]

Knowledge of the relationships and thus the classification of fungi, has developed rapidly with increasingly widespread use of molecular techniques, over the past 10-15 years, and continues to accelerate. Several genera have been found to be polyphyletic, and their generic concepts have subsequently been emended. New names have thus been introduced for species which are phylogenetically distinct from the type species of particular genera. The ending of the separate naming of morphs of the same species in 2011, has also caused changes in fungal generic names. In order to facilitate access to all important changes, it was desirable to compile these in a single document. The present article provides a list of generic names of Ascomycota (approximately 6500 accepted names published to the end of 2016), including those which are lichen-forming. Notes and summaries of the changes since the last edition of 'Ainsworth & Bisby's Dictionary of the Fungi' in 2008 are provided. The notes include the number of accepted species, classification, type species (with location of the type material), culture availability, life-styles, distribution, and selected publications that have appeared since 2008. This work is intended to provide the foundation for updating the ascomycete component of the 'Without prejudice list of generic names of Fungi' published in 2013, which will be developed into a list of protected generic names. This will be subjected to the XIXth International Botanical Congress in Shenzhen in July 2017 agreeing to a modification in the rules relating to protected lists, and scrutiny by procedures determined by the Nomenclature Committee for Fungi (NCF). The previously invalidly published generic names Barriopsis, Collophora (as Collophorina), Cryomyces, Dematiopleospora, Heterospora (as Heterosporicola), Lithophila, Palmomyces (as Palmaria) and Saxomyces are validated, as are two previously invalid family names, Bartaliniaceae and Wiesneriomycetaceae. Four species of Lalaria, which were invalidly published are transferred to Taphrina and validated as new combinations. Catenomycopsis Tibell & Constant. is reduced under Chaenothecopsis Vain., while Dichomera Cooke is reduced under Botryosphaeria Ces. & De Not. (Art. 59). [ABSTRACT FROM AUTHOR]

Two powdery mildews,Erysiphe syringaeand the previously undescribedPhyllactinia syringae, sp. nov., occur on lilac in western North America.Phyllactinia syringaeis found on common lilac, whereasE. syringaeis found on Chinese lilac and, occasionally, common lilac. Infection byP. syringaeis extremely unobtrusive until formation of a hypophyllous mycelial mat with chasmothecia in late fall. Infection byE. syringaein late summer is conspicuous, with its thick, superficial mycelial mat on the leaf upper surface detracting from the aesthetic appearance of the bush. [ABSTRACT FROM PUBLISHER]

The taxonomic history of the common powdery mildew ofChrysanthemum×morifolium(chrysanthemum, florist’s daisy), originally described in Germany asOidium chrysanthemi, is discussed. The position ofO. chrysanthemiwas investigated on the basis of morphological traits and molecular phylogenetic analyses. Based on the results of this study, this species, which is closely related toGolovinomyces artemisae, was reassessed and reallocated toGolovinomyces. The phylogenetic analysis and taxonomic reassessment of the chrysanthemum powdery mildew is supplemented by a morphological description, a summary of its worldwide distribution data, and a brief discussion of the introduction of this fungus to North America.G. chrysanthemidiffers from trueG. artemisiaein that it has much longer conidiophores, is not constricted at the base, and has much larger and most importantly longer conidia. The close affinity ofGolovinomycestoArtemisiaandChrysanthemumspecies signifies a coevolutionary event between the powdery mildews concerned and their host species in the subtribeArtemisiinae(AsteraceaetribeAnthemideae). This conclusion is fully supported by the current phylogeny and taxonomy of the host plant genera and the coevolution that occurred with the host and pathogen. The following powdery mildew species, which are associated with hosts belonging to the tribeAnthemideaeof theAsteraceae, are epitypified:Alphitomorpha depressaβartemisiae(≡Alphitomorpha artemisiae),Erysiphe artemisiae, andOidium chrysanthemi. Erysiphe macrocarpais neotypified. Their sequences were retrieved from the epitype collections and have been added to the phylogenetic tree.Golovinomyces orontii, an additional powdery mildew species onChrysanthemum×morifolium, is reported. This species is rarely found as a spontaneous infection and was obtained from inoculation experiments. [ABSTRACT FROM PUBLISHER]

Two anamorph-typified names are older than I P. psidii i and threaten this name, viz., I Caeoma eugeniarum i , introduced in 1825, and I Uredo neurophila i , which dates back to early 1884. I Austropuccinia psidii i is an economically important plant disease that threatens cultivated myrtaceous host plants worldwide, above all in Australia and South America (Walker in Austral. The involvement of a name for an important plant disease and its continuous application since 1884 are in favour of the maintenance of the epithet ' I psidii i ', now as I Austropuccinia psidii i . [Extracted from the article]

Asexual and sexual morphs of powdery mildews on Fontanesia phillyreoides and Jasminum fruticans , two hitherto unknown host species, have recently been collected in Turkey. Analyses of morphological traits and molecular sequence data led to identifications of the causal agents of the powdery mildew diseases involved. Fontanesia phillyreoides was infected by Phyllactinia fraxini , and the powdery mildew on Jasminum fruticans can be classified as Erysiphe cf. aquilegiae . The latter host showed traces of a co-infection with a second powdery mildew (only asexual morph) belonging to the genus Phyllactinia (= Ovulariopsis ) and morphologically well agreeing with P. fraxini . [ABSTRACT FROM AUTHOR]

With the change to one scientific name for fungal species, numerous papers have been published with recommendations for use or protection of competing generic names in major groups of ascomycetes. Although genera in each group of fungi were carefully considered, some competing generic names were overlooked. This paper makes recommendations for additional competing genera not considered in previous papers. Chairs of relevant Working Groups of the ICTF were consulted in the development of these recommendations. A number of generic names need protection, specifically Amarenographium over Amarenomyces, Amniculicola over Anguillospora, Balansia over Ephelis, Claviceps over Sphacelia, Drepanopeziza over Gloeosporidiella and Gloeosporium, Golovinomyces over Euoidium, Holwaya over Crinium, Hypocrella over Aschersonia, Labridella over Griphosphaerioma, Metacapnodium over Antennularia, and Neonectria over Cylindrocarpon and Heliscus. The following new combinations are made: Amniculicola longissima, Atichia maunauluana, Diaporthe columnaris, D. liquidambaris, D. longiparaphysata, D. palmicola, D. tersa, Elsinoë bucidae, E.caricae, E. choisyae, E. paeoniae, E. psidii, E. zorniae, Eupelte shoemakeri, Godronia myrtilli, G. raduloides, Sarcinella mirabilis, S. pulchra, Schizothyrium jamaicense, and Trichothallus niger. Finally, one new species name, Diaporthe azadirachte, is introduced to validate an earlier name, and the conservation of Discula with a new type, D. destructiva, is recommended. [ABSTRACT FROM AUTHOR]