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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]

The ergot diseases of agricultural and nonagricultural grasses are caused by the infection of Claviceps spp. (Hypocreales, Ascomycota) on florets, producing dark spur‐like sclerotia on spikes that are toxic to humans and animals, leading to detrimental impacts on agriculture and economy due to the downgrading of cereal grains, import–export barriers, reduced yield, and ecological concerns. At least seven phylogenetic lineages (phylogenetic species) were identified within the premolecular concept of C. purpurea s.l. (sensu lato) in agricultural areas and vicinities in Canada and the Western United States. Claviceps purpurea s.s (sensu stricto) remained as the most prevalent species with a wide host range, including cereal crops, native, invasive, and weedy grasses. The knowledge on genetic diversity and distribution of C. purpurea s.s. in North America is lacking. The objective of the present study was to shed light on genetic differentiation and evolution of the natural populations of C. purpurea s.s. Multilocus DNA sequences of samples from Canada and the Western USA were analyzed using a phylogenetic network approach, and population demographic parameters were investigated. Results showed that three distinct genetically subdivided populations exist, and the subdivision is not correlated with geographic or host differentiations. Potential intrinsic mechanisms that might play roles in leading to the cessation of gene flows among the subpopulations, that is, mating and/or vegetative incompatibility, genomic adaptation, were discussed. The neutrality of two house‐keeping genes that are widely used for DNA barcoding, that is, translation elongation factor 1‐α (TEF1‐α) and RNA polymerase II second largest subunit (RPB2), was challenged and discussed. [ABSTRACT FROM AUTHOR]

Phylogenetic analysis based on the ergot alkaloid biosynthesis gene I easE i suggests that I C. zizaniae i is more closely related with I C. arundinis i Pazoutová & M. Kolarík, I C. humidiphila i Pazoutová & M. Kolarík, and I C. spartinae i (R.A. Duncan & J.F. White) Pazoutová & M. Kolarík (Fig. 15 Phylogenies based on translation elongation factor 1- (A) and ergot alkaloid synthase gene (easE) encoding chanoclavine I synthase oxidoreductase (B) showing C. zizaniae in relation to other Claviceps spp. Solvent extracts of ground I C. zizaniae i sclerotia were profiled by UPLC-HRMS and putative ergot alkaloid annotations were assigned based on mass spectral accuracy (±5 ppm) and relative elution order (Sulyok et al. [16]). Indole diterpenes such as paspaline and paspaline-type indole-diterpenoids that are commonly produced by I Claviceps i spp. (Schardl et al. [13]), including I C. humidiphila i and I C. arundinis i (Negård et al. [8]), were not observed in extracts of I C. zizaniae i sclerotia. [Extracted from the article]

A luminous mushroom from Vietnam, identified earlier as Omphalotus aff. illudens (Van, 2009. J Siber Fed Univ. 2:157–171), was studied. Morphological observations of collected fruiting bodies were made in the field. A culture isolated from tissues of one basidiome was studied and the internal transcribed spacer regions (ITS1-2) of the ribosomal RNA repeat were sequenced to confirm identifications. From these observations, the luminous mushrooms collected in Vietnam were identified as Neonothopanus nambi (Speg.) R.H. Petersen & Krisai. To resolve initial sequence ambiguities amplified DNA fragments were cloned and 38 different ITS sequences were obtained from a total of 98 clones, with 14 nt step differences (2% variability) across the entire spectrum of clone sequences. Commonalities in the sequences indicated that the cloned sequences represented two monokaryon mating strains from the basidiome and one possible recombinant. Cloning errors were accounted for by deletion of single occurrence nucleotide variants. Six insertions/deletions and four single nucleotide polymorphisms distinguished the two monokaryon sequences (98% similarity), which differed by 4 bp in length. As many as six multiple occurrence intragenomic polymorphisms in either monokaryon were found to be statistically significant. Possible evolutionary mechanisms for the persistence of intergenomic and intragenomic ITS polymorphisms are discussed. [ABSTRACT FROM AUTHOR]