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A rust specimen with macroscopic similarities to the cereal stem rusts was collected on Elymus sp. from Gansu province, China. Phylogenetic analyses of ITS and COI DNA sequences indicated the fungus was closely related but distinct as a strongly supported sister taxon to the Puccinia graminis species complex. Microscopic examination revealed diagnostic teliospore characteristics, differentiating it from P. graminis and other morphologically similar rusts. Herein, we designate a name for this new lineage, Puccinia chunjii sp. nov. [ABSTRACT FROM AUTHOR]

Based on an overview of progress in molecular systematics of the true fungi (Fungi/Eumycota) since 1990, little overlap was found among single-locus data matrices, which explains why no large-scale multilocus phylogenetic analysis had been undertaken to reveal deep relationships among fungi. As part of the project "Assembling the Fungal Tree of Life" (AFTOL), results of four Bayesian analyses are reported with complementary bootstrap assessment of phylogenetic confidence based on (1) a combined two-locus data set (nucSSU and nucLSU rDNA) with 558 species representing all traditionally recognized fungal phyla (Ascomycota, Basidiomycota, Chytridiomycota, Zygomycota) and the Glomeromycota, (2) a combined three-locus data set (nucSSU, nucLSU, and mitSSU rDNA) with 236 species, (3) a combined three-locus data set (nucSSU, nucLSU rDNA, and RPB2) with 157 species, and (4) a combined four-locus data set (nucSSU, nucLSU, mitSSU rDNA, and RPB2) with 103 species. Because of the lack of complementarity among single-locus data sets, the last three analyses included only members of the Ascomycota and Basidiomycota. The four-locus analysis resolved multiple deep relationships within the Ascomycota and Basidiomycota that were not revealed previously or that received only weak support in previous studies. The impact of this newly discovered phylogenetic structure on supraordinal classifications is discussed. Based on these results and reanalysis of subcellular data, current knowledge of the evolution of septal features of fungal hyphae is synthesized, and a preliminary reassessment of ascomal evolution is presented. Based on previously unpublished data and sequences from GenBank, this study provides a phylogenetic synthesis for the Fungi and a framework for future phylogenetic studies on fungi. [ABSTRACT FROM AUTHOR]

Helminthosporiumasterinum Cooke (=Helminthosporiumpapulosum Anth. Berg, Helminthosporium phomatae Dearn. & House) is redescribed and transferred to Ellisembia because of distinctions in the kind of conidiogenous cell. Polydesmuselegans Durieu & Mont. is redescribed and Helminthosporium densum Sacc. & Roum. and Taeniolellabilgramii S.S. Reddy & S.M. Reddy are its synonyms. Imimyces A. Hern.-Guit. & B. Sutton, typified by H. densum Sacc. & Roum., is a synonym of Polydesmus Mont. Consequent to the exclusion of the type species of Imimyces, a new genus, Imicles, typified by Helminthosporiumleptosporum Sacc. & Roum., is proposed for the residue of species formerly included in Imimyces.Key words: apple, pear, black-pox, Corynespora, Corynesporina, Sporidesmium.Les auteurs redécrivent l'Helminthosporium asterinum Cooke (=Helminthosporium papulosum Anth. Berg, Helminthosporium phomatae Dearn & House) et le tranfèrent au genre Ellisembla sur la base de distinctions dans le type de cellule conidiogène. Ils redécrivent le Polydesmus elegans Durieu & Mont. L'Helminthosporium densum Sacc. & Roum. ainsi que le Taeniolella bigramii S.S. Reddy & S.M. Reddy en sont des synonymes. Imimyces A. Hern.-Guit. & B. Sutton, typifié par l'H. densum Sacc. & Roum., est un synonyme de Polydesmus Mont. Suit à l'exclusion de l'espèce type de l'Imimyces, on propose le nouveau genre Imicles, typifié par l'Helminthosporium leptosporum Sacc. & Roum., pour accomoder les espèces résiduelles incluses jusqu'ici dans l'Imimyces.Mots clés : pomme, poire, tache noire, Corynespora, Corynesporina, Sporodesmium.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

Some species of Tilletia are responsible for diseases in economically important crops, such as wheat and rice. In this study, we sequenced, assembled, and annotated 22 new genomes for Tilletia, with a focus on species causing dwarf bunt (DB; T. controversa), common bunt (CB; T. caries and T. laevis), and rice kernel smut (RKS; T. horrida). We present the first genomes for four other species (T. bromi, T. fusca, T. goloskokovii, and T. rugispora), resulting in the largest and most diverse sample of Tilletia genomes studied to date. Depending on the species and strain, the assembly size ranged from 24.3 to 30.5 Mb and gene prediction resulted in 7138 to 8261 gene models per genome. Phylogenomic analyses with hundreds to thousands of genes revealed significant support for the relationships among certain Tilletia taxa and validated findings of previous molecular studies that employed a small number of genes. Further population-level analyses showed two distinct populations of DB and CB: T. controversa (DB) as a single population and another intermixed population of T. caries and T. laevis (CB). No evidence of geographic isolation was observed within these populations. Our phylogenomic analyses also supported previous multigene hypotheses that multiple lineages of Tilletia may cause RKS. Collectively, our results suggest that taxonomic revisions are needed for the RKS-causing pathogens and provide convincing evidence for formally recognizing the CB-causing taxa as one species, named T. caries (synonym T. laevis). Overall, our study significantly enhances genomic resources for Tilletia, offers insights into phylogenetic relationships and population structure, and provides whole genome sequences for future studies. [ABSTRACT FROM AUTHOR]

Provides information on Asteromassaria olivaceohirta, a plant pathogen. Distribution of the pathogens throughout the range of Morus rubra in Canada; Description of mature infections of A. olivaceohirta; Classification and phylogenetic relationships.

Triticale (× Triticosecale), was initially produced by crossing wheat (Triticum) with rye (Secale). Although still a minor crop in Canada, triticale grain is used both as human food (in bread, pastry products, and the brewing industry) and as livestock feed (Larter 2015). In September 2023 typical leaf rust samples were observed and collected in winter Triticale at Lacombe, Alberta. Typical exposed rust colored uredinia were mainly on adaxial leaf surface. Urediniospores obovoid, ellipsoid or globoid, measured 24-33 × 19-26 µm; with yellow-brown echinulate wall 1-1.5 µm thick. These spores mostly had 8 to 9 scattered germ pores, approximately bizonate with moderate to strong internal ring. Telia not present. Due to the absence of the telial stage, the morphological features of uredinia and urediniospores align our species with Puccinia triticina and P. recondita. These species have overlapping uredinial characteristics and can potentially both cause disease on Triticale (Yekelo et al. 2019). For testing pathogenicity on Triticale, two-week-old winter Triticale seedlings were infected with single pustule isolate from the Albertan leaf rust sourced from Triticale (AB-1). For seedling inoculation, we used 20 mg of pure urediniospores suspended in 5-6 ml of NOVEC 7100™ Engineered fluid, applied with an airbrush compressor system equipped with a 0.3 mm nozzle. All inoculated plants were kept in a dew chamber at 13°C for 24 hours in the dark, and then transferred to a Reach-In growth chamber with a 16-hour photoperiod (21°C day/15°C night). After 10 days, all inoculated seedlings showed uredinia. Control plants that were only sprayed with NOVEC 7100 and kept under the same conditions remained healthy, showing no rust symptoms. To clarify the identity of leaf rust, we sequenced the nuclear ribosomal rRNA internal transcribed spacer region (ITS) and elongation factor 1 alpha gene (EF1-a) for both the field collection (DAOM 985259) and the single pustule inoculated collection (DAOM 985258) and the data were deposited in NCBI GenBank (accession # PQ317950 and PQ317949 for ITS and PQ338170 and PQ338169 for EF1-a, respectively). Obtained sequences of both field and the inoculated collections were identical and shared %100 identity with available sequences of P. triticina in GenBank (MT955180 for ITS and JX533504 for EF1-a) (Liu et al. 2013). To further investigate the pathogenicity of the Albertan leaf rust isolate (AB-1) on Triticale, we conducted additional rounds of inoculation tests. In those experiments, two-week-old seedlings of winter rye and Avocet wheat were inoculated under the above-mentioned conditions and methods. After 9 to 10 days, both rye and wheat plants showed uredinia on the infected leaves. This indicates that the Triticale isolate of leaf rust was capable of infecting rye and wheat in addition to Triticale. Since Triticale is primarily planted as a forage or cover crop, its susceptibility to wheat leaf rust could contribute to the build-up of inoculum and subsequent infection of commercial wheat crops (Yekelo et al. 2019). Our research showed, there was no record of leaf rust (P. triticina) on Triticale based on USDA Fungal Databases (https://fungi.ars.usda.gov/) and also no herbarium specimen of leaf rust on Triticale in Canada and United States based on MyCoPortal (https://www.mycoportal.org). To our knowledge this is the first morphologically and molecularly documented report of P. triticina on Triticale in Alberta and probably in Canada.

Several fungi classified in the genus Tilletia are well-known to infect grass species including wheat ( Triticum ). Tilletia indica is a highly unwanted wheat pathogen causing Karnal bunt, subject to quarantine regulations in many countries. Historically, suspected Karnal bunt infections were identified by morphology, a labour-intensive process to rule out other tuberculate-spored species that may be found as contaminants in grain shipments, and the closely-related pathogen T. walkeri on ryegrass ( Lolium ). Molecular biology advances have brought numerous detection tools to discriminate Tilletia congeners (PCR, qPCR, etc.). While those tests may help to identify T. indica more rapidly, they share weaknesses of targeting insufficiently variable markers or lacking sensitivity in a zero-tolerance context. A recent approach used comparative genomics to identify unique regions within target species, and qPCR assays were designed in silico. This study validated four qPCR tests based on single-copy genomic regions and with highly sensitive limits of detection (~200 fg), two to detect T. indica and T. walkeri separately, and two newly designed, targeting both species as a complex. The assays were challenged with reference DNA of the targets, their close relatives, other crop pathogens, the wheat host, and environmental specimens, ensuring a high level of specificity for accurate discrimination.

DNA phylogenetic comparisons have shown that morphology-based species recognition often underestimates fungal diversity. Therefore, the need for accurate DNA sequence data, tied to both correct taxonomic names and clearly annotated specimen data, has never been greater. Furthermore, the growing number of molecular ecology and microbiome projects using high-throughput sequencing require fast and effective methods for en masse species assignments. In this article, we focus on selecting and re-annotating a set of marker reference sequences that represent each currently accepted order of Fungi. The particular focus is on sequences from the internal transcribed spacer region in the nuclear ribosomal cistron, derived from type specimens and/or ex-type cultures. Re-annotated and verified sequences were deposited in a curated public database at the National Center for Biotechnology Information (NCBI), namely the RefSeq Targeted Loci (RTL) database, and will be visible during routine sequence similarity searches with NR_prefixed accession numbers. A set of standards and protocols is proposed to improve the data quality of new sequences, and we suggest how type and other reference sequences can be used to improve identification of Fungi. Database URL: http://www.ncbi.nlm.nih.gov/bioproject/PRJNA177353., (Published by Oxford University Press 2013. This work is written by US Government employees and is in the public domain in the US.)