Mycoscience: Advance Publication doi: 10.47371/mycosci.2020.12.003 Full Paper (Received July 3, 2020; Accepted December 9, 2020) J-STAGE Advance Published Date: March 13, 2021
Full paper
Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
Miao Liua,d,*, Uwe Braunb,d, Susumu Takamatsuc, Sarah Hambletona, Parivash Shoukouhia,
Kassandra R. Bissona, Keith Hubbarda
a Biodiversity and Bioresources, Ottawa Research and Development Centre, Agriculture and
Agri-Food Canada, Ottawa, Ontario K1A 0C6, Canada. b Martin Luther University, Institute of Biology, Department of Geobotany, Herbarium, Halle
(Saale) 06099, Germany. c Faculty of Bioresources, Mie University, Tsu 514-8507, Japan. d First two authors should be considered as havingPublication equal contribution.
*Corresponding author email: [email protected]
Text: 61 pages; tables: 1; figures: 9
Supplemental materials: 4 Supplementary Figures, 1 Supplementary Appendix text Advance
- 1 - Mycoscience: Advance Publication
ABSTRACT
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.
Keywords: Ascomycota, E3 ubiquitin-protein ligase, Poaceae, typification, unnamed orthologous genes Advance Publication
- 2 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
1. Introduction
Powdery mildew fungi are responsible for a variety of common and important diseases of cereals and grasses (Poaceae), many have world-wide distributions and some cause significant yield losses and quality reduction in the cereal production (Everts, Leath, & Finney, 2001). The causal pathogen of the powdery mildew disease on wheat (Triticum aestivum L.) was first described as
Erysiphe graminis DC. (De Candolle, 1815). Thereafter, the species has been redescribed many times under various names legitimately or illegitimately, as reviewed by Braun and Cook (2012).
According to Speer (1975 [1973–1974]), Golovin erected Blumeria to separate wheat powdery mildew from other Erysiphe spp. based on Blumer’s observations (Blumer, 1933; Golovin,
1958). However, the erection of a new genus failed to comply with the rules of nomenclature in force at the time due to the absence of a Latin description, therefore the generic name, Blumeria
Golovin 1958, was considered illegitimate. Speer redescribed the genus Blumeria properly, made the combination B. graminis (DC.) Speer and identified seven host species in addition to T. aestivum (Speer, 1975 [1973–1974]). Intra-specific variation was noted very early by Saccardo who distinguished the form E. graminis f. dactylis-glomeratae (Exs: Sacc. Mycoth. Ven. 606,
1876) from others. Jaczewski (1927) introduced 26 formae (host/substrate forms), corresponding to each host genus. Marchal (1902) introduced the first formae speciales (f. spp.) for E. graminis based on inoculation experiments. Several subsequent authors added additional formae and formae specialesAdvance (Marchal, 1902; Jaczewski, 1927; Publication Mains, 1933; Cherewick, 1944; Bunkina,
1967, 1973, 1974). In the latest classification of powdery mildew, B. graminis is the only species in this genus, which is classified in the monotypic tribe Blumerieae within Erysiphaceae (Braun
- 3 - Mycoscience: Advance Publication
& Cook, 2012). The host species have been recorded in 107 genera of Poaceae (Braun & Cook,
2012, also see Taxonomy section). Some are common hosts with a wide distribution, such as
Avena, Bromus, Dactylis, Elymus, Hordeum, Poa, Secale, and Triticum. Some are rarely recorded, suggesting occasional host jumps by the pathogen.
Multi-locus sequences analyses (MLSA) conducted by Inuma, Khodaparast and Takamatsu
(2007) recovered nine lineages correlated with host specialization, and demonstrated reproductive isolation between the lineages. Among these lineages, some had a restricted host range of a single genus or species, i.e. lineages on Avena, Bromus, Diarrhena and Hordeum, while others infected host species in 2 or 3 genera, i.e. lineages of Dactylis, Poa and Triticum.
Bromus hosted three lineages. Validation of these phylogenetic species (lineages) within the B. graminis complex required comprehensive morphological analyses. The purpose of this study was to describe and distinguish eight of them by a combination of molecular characters, morphology and putative host preference, and provide formal taxonomic names. The ninth lineage on Diarrhena (see Inuma et al., 2007) was not included because only one specimen was available.
2. Materials and methods
2.1. Fungal specimens and gDNA extraction
For DNAAdvance MLSA and morphological examination, Publication 163 specimens of B. graminis s. lat. on cereal crops and various grasses were borrowed from five international herbaria: Canadian
National Mycological Herbarium (DAOM), U.S. National Fungus Collections (BPI), Martin-
- 4 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
Luther-Universität, Institut für Biologie, Bereich Geobotanik und Botanischer Garten Herbarium
(HAL), the National Museum of Nature and Science (Tokyo, TNS), and Conservatoire et Jardin
botaniques de la Ville de Genève (G). Previously developed DNA sequences, i.e. 49 rDNA-ITS,
25 CHS1 were downloaded from GenBank as references. An additional 126 specimens from
Senckenberg Museum für Naturkunde Görlitz (GLM) were examined for morphology (by UB).
For genomic DNA extraction, three or four 2 mm discs of infected leaf tissues were excised
from specimens using Disposable Biopsy Punches Integra™ Miltex® (VWR, Mississauga
Ontario, Canada). Alternatively, similar amounts of mycelia and/or chasmothecia were removed
from leaf surfaces using tweezers. Macherey-Nagel Nucleomag® 96 Trace kit (Macherey-Nagel,
GmbH & Co. KG, Düren, Germany) on a KingFisher Flex magnetic particle processor (Thermo
Fisher Scientific Oy, Vantaa, Finland), or an E.Z.N.A. Forensic DNA Kit (Omega Biotek, Inc.,
Norcross, Georgia, United States) were used for DNA extraction according to the manufacture’s
protocols with minor modifications. The modifications were as follows: prior to extraction,
samples were frozen using liquid nitrogen and ground using sterile disposable micro-centrifuge
tube pestles (PES-15-B-SI Axygen, Corning, New York, USA), and DNA was suspended in 70
µL of elution buffer. Extracted DNA aliquots were stored at -20 °C and the stock DNA was
stored at -80 °C.
2.2. PCR, sequencing and analyses
The rDNAAdvance-18S (~100 bps)-ITS-28S (~50 bps, Publication abbreviated as ITS region in followed text) region was amplified with two forward and two reverse primers in various combinations, P7
(Mori, Sato, & Takamatsu, 2000), PMITS1, PMITS2 (Cunnington, Takamatsu, Lawrie, & Pascoe,
- 5 - Mycoscience: Advance Publication
2003) and ITS4 (White, Bruns, Lee, & Taylor, 1990), and a portion of the chitin synthase gene
(CHS1) with primers CHS1-E1f (Seko, Heluta, Grigaliunaite, & Takamatsu, 2011) and CHS1-B3r or CHS1-2r (Inuma et al., 2007). Fragments of two unnamed orthologous genes were amplified using primers designed using the published alignment of 93 phylogenetic informative genes from
31 whole genome sequences of B. graminis (Menardo, Wicker, & Keller, 2017). Geneious R10 primer design module (Biomatters, Aukland, New Zealand) was used to search for candidate oligos with all parameters set as default. The final primer sequences were: locus 1 (Bgt-1929 hypothetic protein exon 1–2 on chromosome 4): FM_27522F 5’-
TGTGACGATGGAGATTGTGA-3’ and FM_27868R 5’-CCCATTCGCTGATTGCATAA-3’; and locus 2 (Bgt-4572 exon 3 on chromosome 9, 81% match with E3 ubiquitin-protein ligase in
Venustampulla echinocandica Unter., Réblová & Bills): FM_110716F 5’-
ATGGAAGGAGTTGATGCAGA-3’ and FM_110946R 5’-GAACTGCTCATCAATTCGCT-3’
(Etymology of primers: FM stands for the initial of Fabrizio Menardo, first author of the 31 B. graminis genome sequences; numbers = location on the concatenated alignment of 93 orthologous loci; F = forward, R = reverse).
Polymerase chain reaction (PCR) was performed in 10 μL reactions containing 1 μL of gDNA, 1× Titanium Taq buffer (with 3.5 mM MgCl2), 0.1 mM dNTPs, 0.08 µM each of forward and reverse primer, 0.5× Titanium Taq DNA Polymerase (BD Biosciences, San Jose, California,
USA), and 0.01 mg bovine serum albumin (BSA) on a TProfessional thermocycler (Biometra, Göttingen,Advance Germany). Touchdown thermocycling Publication protocols were used for rDNA-ITS and two anonymous loci: initial denaturation at 95 °C for 3 min, followed by 10 cycles of 95 °C for 30 s, annealing at 63 °C (decrease 0.5 ºC per cycle) for 45 s, and extension at 72 °C for 2 min, then 20 cycles of 95 °C for 30 s, annealing at 58 °C for 30 s, and extension at 72 °C for 2 min, with a final
- 6 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
extension at 72 °C for 10 min. For CHS1, an initial denaturation at 95 °C for 3 min, followed by 6 cycles of 95 °C for 1 min, annealing at 58 °C (decrease 0.5 ºC per cycle) for 45 s, and extension at
72 °C for 1 min 30 s, then 33 cycles of 95 °C for 30 s, annealing at 55 °C for 30 s, and extension at 72 °C for 2 min, with a final extension at 72 °C for 10 min. The PCR products were visualized by using Ethidium Bromide on 1% agarose gels in 1× TBE buffer.
PCR products were amplified with the same primers for Sanger sequencing using ABI
BigDye™ Terminator v3.1 Cycling Sequencing Kits with BigDye® Seq Mix diluted 1:8. In 10
µL reaction, volumes of each reagent were 1.75 µL of 5× Sequencing buffer, 2.5 µL of 20% trehalose, 0.5 µL of BigDye® Seq Mix, 0.5 µL of 3.2 µM primer, 3.75 µL sterile HPLC water and 1 µL of PCR product without purification. Thermocycler profiles for the sequencing reactions had an initial denaturation at 95 °C for 3 min, followed by 40 cycles at 95 °C for 30 s, annealing at 55 °C for 15 s and extension at 60 °C for 2 min. An Applied Biosciences Prism® 3130xl
Genetic Analyzer (Life Technologies™, California, USA) was used to generate DNA sequences from the sequencing amplification reactions. Sequences were edited using Sequencher 5.4.6
(Gene Codes Corporation, Michigan, USA) or Geneious 10.2.3 (https://www.geneious.com,
Biomatters, Aukland, New Zealand).
DNA sequences were aligned with MAFFT online version (Katoh, Rozewicki, & Yamada,
2017). Parsimony and Bayesian inference analyses were conducted on the matrices of each individual locus and a concatenated alignment of four loci for a subset of samples. The most parsimonious trees were searched for using heuristic branch-swapping algorithm, tree-bisection- reconnectionAdvance (TBR), 200 replicates, number of rearrangementsPublication per replicate limit 25000 in
PAUP* 4.0b10 (Swofford, 2002), 2000 bootstrap replicates. The best-fit models selected by
Modeltest 3.7 (Nylander, 2004) were TrNef+G for ITS, CHS1 and Bgt-1929, and Trn+G for Bgt-
- 7 - Mycoscience: Advance Publication
4572. For Bayesian inference, using MrBayes V3.2.6 (Ronquist et al., 2012), models were set as
Nst = 6, rates = invgamma; mcmc were 100 000 000 generations, sampling per 2000 generations;
2 parallel runs each with 4 chains were simultaneously implemented. The runs were terminated when the standard deviation of the average split frequency was lower than 0.03.
Outgroups were selected for analyses of each gene by BLAST searching for available sequences for the closest relatives in NCBI GenBank. These were Podosphaera macularis
(Wallr.) U. Braun & S. Takam. MH687414 for ITS, V. echinocandica chitin synthase 1 (XM
032013628.1 range 2317–2600) for CHS1, Rhynchosporium graminicola Heinsen (= R. commune
Zaffarano, B.A. McDonald & A. Linde) hypothetic protein KJ410022.1 range 2906–3301 for Bgt-
1929; V. echinocandica E3 ubiquitin-protein ligase XM 032013958.1 range 1811–2040 for locus
Bgt-4572.
2.3. Microscopy
The infection signs and symptoms were recorded by examining all material in the specimen
packets by naked eye, and by a Leica M165C stereo microscope (Leica Microsystems (Canada)
Inc., Ontario, Canada). Colors were recorded using standardized color codes according to
Kornerup and Wanscher (1978). Photographs were taken with a Leica DFC425 camera and
processed using Leica Application Suite software (LAS v4.12.0, Leica Microsystems
(Switzerland), Ltd., Heerbrugg, Switzerland). For examining microscopic features of primary
and secondaryAdvance hyphae, hyphal appressoria, conidia, Publication conidiophores, chasmothecia, and asci, the
infected leaves were rehydrated using the lactic acid method described by Shin and La (1993)
with a minor modification. A Microscope Slide Warmer (VWR, Mississauga Ontario, Canada)
- 8 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
was used instead of the alcohol burner for more gentle heating to avoid extreme morphological changes of organ shapes and sizes. The rehydrated mycelia and fruiting structures were scraped from the leaf surface using forceps and mounted in a drop of lactic acid, with or without cotton blue, on microscope slides. Observations were made using a Zeiss Imager M2 (Carl Zeiss
Canada Limited, Ontario, Canada). Microphotographs were taken with an Axiocam 503 Color camera and analysed by ZEN (blue edition) 2.6 pro (Carl Zeiss Microscopy GmbH, Jena,
Germany); or a Zeiss Axio Scope.A1 (Germany) and Axiocam ERc 5s. At least thirty measurements were made for the sizes whenever possible.
For scanning electron microscopy (SEM), infected leaf material from dried herbarium specimens was rehydrated in a moist chamber (a petri-dish with layers of moist filter paper inserted with the lid on) for 1–2 h. Small pieces of leaf tissue with spores were mounted on carbon double sticky tape on aluminum stubs and coated with an 8 nm thick layer of gold in an
Emitech K550V sputter coater (EM Technologies Ltd., Ashford, Kent, England). The samples were imaged on a Quanta 600 SEM operating at 20 kV (FEI Company TM, Brno, Czech
Republic).
3. Results
3.1. Sequencing and molecular phylogeny
For the total of 163 samples, varied numbers of sequences were obtained for each locus attempted:Advance 48 rDNA-ITS, 61 CHS1, 103 Bgt-1929 Publication and 144 Bgt-4572. Adding reference sequences downloaded from GenBank (49 ITS and 25 CHS1) resulted in matrices of 97 taxa with 778 characters for ITS, and 87 taxa with 320 characters for CHS1. For the two hypothetical
- 9 - Mycoscience: Advance Publication
protein loci, only one reference sequence was downloaded from GenBank as outgroup (also see paragraph in 2.2), resulting in matrices of 104 taxa with 391 characters for Bgt-1929, and 145 taxa with 226 characters for Bgt-4572. Comparisons of the four loci showed that ITS had the poorest performance in amplification and lowest number of informative characters (86/778 =
11%). CHS1 had the highest percentage of informative characters, i.e. 100/320 = 31%
(Supplementary Figs. S1–S4 legends), however, the number of lineages amplified by CHS1 was not as high as two hypothetical protein loci (Supplementary Figs. S1–S4). For instance, none of the B. americana samples was amplified, therefore B. americana was not present in the CHS1 tree (Supplementary Fig. S2). A large number of B. graminicola were only amplified by Bgt-
1929 and Bgt-4572. However, B. bromi-cathartici and B. bulbigera were not represented on Bgt-
1929 and Bgt-4572 trees because only a few samples for each species were available and PCR amplification was not successful. All trees agreed on the separation of the lineages that were included, in general. A specimen on Anthoxanthum nitens (Weber) Y. Schouten & Veldkamp (=
Hierochloe odorata (L.) P. Beauv., synonym recorded on specimen packets) from Saskatchewan
(DAOM 4071) grouped in B. graminis s. str. on the ITS tree, however in B. graminicola on all other trees. The identification was determined based on majority rule, but the possibility of a mixed infection or DNA processing error cannot be ruled out. The identities of several orphan lineages cannot be determined, and these are labelled as Blumeria sp. (Table 1; Fig. 1;
Supplementary Figs. S1, S2, S4). The species relationships were not strongly supported in any of the trees based on individual genes, indicating limited phylogenetic signals were present for the deeper relationships,Advance therefore a holistic approach Publication was applied as follows.
Sequences of the 63 samples which were successfully sequenced for at least three loci were concatenated. With missing loci coded as gaps, the matrix resulted in 1639 characters. Added to
- 10 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
this matrix were ten reference sequences of ITS and CHS from GenBank. The outgroup sequences used for individual locus analyses were concatenated as a composite outgroup taxon.
The phylogeny generated from the concatenated alignment (Fig. 1) was congruent with each individual locus (Supplementary Figs. S1–S4) in terms of the separation of the eight lineages, however had much higher statistical supports for those lineages and their internal branches. This is particularly evident for the B. americana and B. dactylidis clades, showing as paraphyletic on
ITS and Bgt-1929 respectively due to low statistical supports. On all the phylogenetic trees, seven lineages corresponding to the described species here appear coherent, while B. graminicola included several sub-lineages which may be indicative of further cryptic speciation.
This hypothesis could be evaluated by further studies of morphological or other biological characters.
3.2. Morphological observations
Variations in the following morphological characters were found between species, but also within species. A few features are diagnostic in some cases although many are shared by several species. It is recommended to use the key and DNA analyses for identification. For the lists of additional specimens examined for each described species in the taxonomy section, see
Supplementary Appendix 1.
3.2.1. AdvancePrimary mycelium Publication
- 11 - Mycoscience: Advance Publication
The development of all Blumeria spp. is initiated by the formation of the primary hyphae/mycelia (PH/PM), which are mostly flexuous, branched, septate, thin-walled, and smooth. Differences occur in the color of mycelia. In some species the mycelia remain white
(whitish to greyish white) through the growing season, e.g. B. graminicola, while in other species become pigmented with age, showing as powdery patches in pale yellow (B. bromi- cathartici and B. bulbigera), orange to light brown (B. graminis s. str., B. americana, B. avenae and B. dactylidis) or purplish brown (B. hordei). Another variation is the duration of primary mycelium development. In almost all species, the formation of the primary mycelium along with the asexual morph starts in spring (based on observations in temperate regions), and lasts until summer in parallel with secondary hyphae and chasmothecia. One exception is B. graminis s. str. in that the development of primary mycelia is hindered by the formation of the sexual morph.
For B. graminicola, on the other hand, the development of the primary mycelia along with the asexual morph lasts until late autumn or early winter.
3.2.2. Hyphal appressoria
The hyphal appressoria are mostly nipple-shaped, occasionally lobe- or fork-shaped, 3–6 µm diam, singly or in opposite pairs on hyphal cells. The lobe-shaped morphology was observed in
B. americana, B. dactylidis, B. graminis s. str.; fork-shaped in B. americana.
3.2.3. AdvanceSecondary mycelium Publication
- 12 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
The secondary mycelia (SM) usually set in around late spring to early summer, mostly along with the emergence of chasmothecia. The secondary hyphae (SH) are bristle-like, usually curved-falcate shaped, sometimes filiform, up to about 500 µm long and 3–7 µm wide, attenuated towards the tip or subcylindrical, soon becoming thick-walled; walls 1–2.5 µm wide, colorless and smooth; lumen narrow, 1–2 µm, later often “closed” (almost without any lumen).
The shape and size of the SH are very characteristic and diagnostic for the genus Blumeria.
However, among species, the variations are subtle including in pigmentation, septation and branching that are often shared by several species. For instance, the wall of the SH in B. graminis s. str., B. americana and B. hordei becomes pigmented with age, ranging from orange, ochraceous to brown; however, in other species (B. bulbigera, B. dactylidis, B. graminicola), remains whitish to dingy greyish white, or at most somewhat yellowish. Branched SH was observed in B. graminis s. str., more than two septa were observed in B. bulbigera and B. graminicola, but unbranched and aseptate (only one basal septum) otherwise.
3.2.4. Conidiophores and conidia
The conidiophores arise from the upper surface of hyphal mother cells, usually towards one end (septum), but occasionally in the middle, composed of a foot-cell with bulbous swelling,
(2–)3–5(–7) shorter cells and a catenescent conidium chain with a terminal conidium (primary conidium, only with a basal hilum) and several catenate conidia (secondary conidia, with hila at the apex and base). Foot-cells 20–55 × 5–7 µm, bulbous swellings (8–)9–15 µm diam, basal septum atAdvance the junction with the supporting hypha Publication or slightly elevated to 5(–10) µm; shorter cells,
10–30 µm long; conidia 20–35(–40) × (9–)10–16(–18) µm (dried herbarium material) or 24–40
× (10–)11–18(–20.5) µm (fresh material), length/width ratio 1.5–2.6(–3.1), hila (3–)4–6 µm
- 13 - Mycoscience: Advance Publication
wide, primary conidia broad ellipsoid-ovoid, secondary conidia broad ellipsoid, barrel-shaped, oblong, fusiform, ovoid, ellipsoid to lemon-shaped (turgescent conidia usually broad ellipsoid, dry and older conidia often limoniform). The shapes and sizes of conidiophores and conidia are usually variable within species, and overlap between species. Other variations include the branched foot-cells and double foot-cells arising from one mother cell in parallel, as observed in
B. americana, B. avenae and B. graminicola. The formation of pigmentation and the development of conidiophores are coincident with the primary hyphae. Blumeria graminicola is evidently distinct by producing the asexual morph until late fall or early winter, lasting much longer than other species, and remaining white through the growing season (also see primary mycelia section). This observation agrees with Blumer’s note on the powdery mildew on Poa spp. (Blumer, 1967). Different from most species, B. bromi-cathartici produces more uniform conidia, oblong, relatively long and narrow, 28–43 × 12–17.5 µm, with a length/width ratio of
1.7–3.2, and somewhat wider hila, 5–7.7 µm. Limoniform conidia have been observed in all
Blumeria species. The conditions favoring this conidial shape are not quite clear, but age and turgescence seem to be factors. Fully turgescent conidia, including those gently heated in lactic acid, are usually less limoniform. SEM of the conidial apical wall shows a thickened patch with or without a dent in the middle for most species, however B. dactylidis does not have this characteristic.
3.2.5. AdvanceChasmothecia Publication Mature chasmothecia are gregarious or more or less scattered, mostly immersed in dense mycelial patches or layers, surrounded by bristle-like secondary hyphae, mostly dark brown to black, semi-globose or short cone-shaped with a flat top surface, with or without depression in
- 14 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
centre, range from 160 to 285 µm diam. Appendages are mycelioid, sparse, shorter than chasmothecium diam. Asci are broad ellipsoid, ellipsoid, obovoid, ovoid, pyriform, 47–73 × 30–
58 µm, with or without a stalk. The stalk is up to 18 µm long, branched or unbranched. The asci of B. graminicola look more stout (wider) than in other species (excluding B. avenae and B. bromi-cathartici, not observed). The ascus stalks of B. bulbigera are evidently long and unbranched, B. americana branched and wiggled.
3.3. Taxonomy
Blumeria Golovin ex Speer, Sydowia 27: 2, [1973–1974] 1975, nom. cons. [Art. 14.1, see
(Braun, 2013)].
≡ Blumeria Golovin, Sborn. Rabot. Inst. Prikl. Zool. Fitopatol. 5: 124, 1958, nom. inval. (Art.
39.1).
≡ Erysiphe sect. Blumeria (Speer) U. Braun, Feddes Repert. 88: 659, 1978.
= Oidium Link, in Willd., Sp. pl. 4, 6(1): 121, 1824, nom. cons. (Art. 14) [type species – Oidium monilioides (Nees) Link, nom. sanct.], nom. rej. (Art. 56.1), see Braun (2013).
= Erysiphe sect. Bulbigera Sawada, Special Bull. Agric. Exp. Sta. Gov. Formosa 19: 149, 1919.
= Erysiphe sect. Graminis Homma, J. Fac. Agric. Hokkaido Imp. Univ. 38: 320, 1937, nom. inval. (Art. 39.1).
= Erysiphe sect. Monilioides S. Blumer, Echte Mehltaupilze (Erysiphaceae): 173, 1967, nom. inval. (Art. 39.1).
= ErysipheAdvance auct. p.p. Publication
Host and distribution: POACEAE subfam. ARUNDINOIDEAE tribe Molinieae, Molinia,
Phragmites; subfam. BAMBUSOIDEAE tribe Arundinarieae, Phyllostachys; subfam.
- 15 - Mycoscience: Advance Publication
CHLORIDOIDEAE tribes Cynodonteae, Buchloe, Chloris, Cleistogenes, Cynodon, Dinebra,
Leptochloa, Lepturus, Muhlenbergia; Eragrostideae, Eragrostis; Zoysieae, Spartina,
Sporobolus; subfam. DANTHONIOIDEAE tribe Danthonieae, Danthonia, Schismus; subfam.
ORYZOIDEAE tribe Oryzeae, Ehrharta, Leersia, Zizania; subfam. PANICOIDEAE, tribes
Andropogoneae, Andropogon, Phacelurus, Saccharum; Paniceae, Cenchrus, Digitaria,
Oplismenus, Panicum, Setaria; subfam. POOIDEAE tribes Brachypodieae, Brachypodium;
Bromeae, Boissiera, Bromus; Diarrheneae, Diarrhena; Meliceae, Glyceria, Melica; Nardeae,
Nardus; Poeae, Agrostis, Alopecurus, Ammochloa, Anthoxanthum, Apera, Arrhenatherum,
Avena, Beckmannia, Briza, Calamagrostis, Catapodium, Coleanthus, Corynephorus, Cutandia,
Dactylis, Deschampsia, Desmazeria, Dichelachne, Echinaria, Eremopoa, Festuca, Gastridium,
Gaudinia, Helictochloa, Helictotrichon, Holcus, Koeleria, Lagurus, Lamarckia, Lolium,
Macrochloa, Mibora, Milium, Nardurus, Parapholis, Phalaris, Phippsia, Phleum, Pholiurus,
Pilgerochloa, Poa, Polypogon, Psilurus, Puccinellia, Rostraria, Sclerochloa, Sesleria,
Sphenopholis, Trisetum, Vulpia; Stipeae, Achnatherum, Orthoraphium, Piptatherum, Stipa;
Triticeae, Aegilops, Crithopsis, Dasypyrum, Elymus, Eremopyrum, Hordelymus, Hordeum,
Leymus, Pascopyrum, Psathyrostachys, Pseudoroegneria, Secale, Taeniatherum, Thinopyrum,
Triticale, Triticum, ×Aegilotriticum; Worldwide distribution.
Notes: Host range and distribution were based on collections examined, Braun and Cook (2012),
Amano (1986), supplemented by data from numerous additional publications, including (Ershad,
1995; Sharma & Khare, 1995; Mendes et al., 1998; Crous, Phillips, & Baxter, 2000; Shin, 2000;
Ahmad,Advance Agarwal, Bambawal, & Puzari, 2007; Voytyuk,Publication Heluta, Wasser, Nevo, & Takamatsu,
2009; Adhikari, 2017; U.S. National Fungus Collections Fungus-Host Database, https://nt.ars- grin.gov/fungaldatabases/fungushost/fungushost.cfm; accessed on May 25, 2020).). The higher
- 16 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
classification of host genera was sourced from GRIN Global Web v.1.10.6.2
(https://npgsweb.ars-grin.gov/gringlobal, accessed on 25 May 2020). Some host records only appeared once or twice, suggesting that either an occasional host jump might be involved or that the records were based on misidentifications. Several of such collections from Germany on unusual hosts have been examined, e.g. on Brachypodium pinnatum (L.) P. Beauv. (GLM-
F48842), Digitaria sanguinea Weber (GLM-F49123), Echinochloa crus-galli (L.) P. Beauv.
(GLM-F79561), Holcus lanatus L. (GLM-F96652, 104923), Melica ciliate L. (GLM-F48416),
Molinia caerulea (L.) Moench (GLM-F51666), Sesleria albicans Deyl. (GLM-F47242), Setaria viridis (L.) P. Beauv. (GLM-F48849), Trisetum flavescens (L.) P. Beauv. (GLM-F94266), on which B. graminis s. lat. could not be found. There is a possibility that the host range is overstated.
The genus name Oidium Link (1824), typified with O. monilioides (Nees) Link, was previously conserved against Oidium Link (1809), with O. aureum (Pers.) Link as type (current name: Botryobasidium aureum Parmasto), basically in order to maintain the name Oidium for asexual morphs of powdery mildews. However, since the Melbourne code was in effect in 2012
(ICN, Turland et al., 2018), Oidium, typified by O. monilioides, an anamorph-typified name belonging to Blumeria, had to be considered an older heterotypic synonym of Blumeria.
Therefore, Braun (2013) proposed to conserve the teleomorph-typified genus name Blumeria against Oidium. This proposal was approved by the General Committee and Blumeria is listed as a conserved name in the appendix of the ICN (Turland et al., 2018).
Advance Publication
Blumeria graminis (DC.) Speer, Sydowia 27(1–6):2, 1975 [1973–1974], s. str. (emend.)
Fig. 2A–I.
- 17 - Mycoscience: Advance Publication
≡ Erysiphe graminis DC., Fl. franç. 6: 106, 1815.
Alphitomorpha communis γ graminearum Wallr., Verh. Ges. Naturf. Freunde Berlin 1: 31,
1819.
Erysibe communis var. graminum Link, Sp. pl. 4, 6(1): 106, 1824.
Erysiphe communis a. graminearum (Wallr.) Rabenh., Deutschl. Krypt.-Fl. 1: 232, 1844.
E. communis z. graminis (DC.) Fr., Syst. mycol. 3: 242, 1829.
= Oidium tritici Lib., Pl. Crypt. Arduenna (Liège), Fasc. 4, no. 358, 1830. Lectotype
(designated by Braun & Kirk, 2019: 88): on leaves of Triticum repens L. ( Elymus repens
(L.) Gould), sine loco et anno, Lib., Pl. Crypt. Arduenna 385 (PRM 685898); isolectotypes:
Lib., Pl. Crypt. Arduenna 385 (e.g., BR, FH, G, ILLS 529, K, S-F49308).
Torula tritici (Lib.) Corda, Icon. Fung. 5: 51, 1842, nom. illeg. (Art. 53.1), non Corda, 1837.
= Torula rubella Bonord., in Rabenh., Fungi Eur. Exs. (Klotzschii Herb. Viv. Mycol.
Continuatio, Ed. Nova, Ser. Sec.), Cent. 3: no. 281, 1860 [Bot. Zeitung 19: 103, 1861; Flora
44: 158, 1861].
[Erysiphe graminis f. sp. tritici E. Marchal, Compt. Rend. Acad. Sci. (Paris) 135: 211, 1902.]
[Erysiphe graminis f. sp. secalis E. Marchal Compt. Rend. Acad. Sci. (Paris) 135: 211, 1902.]
Diagnosis: Development of the primary mycelium and the asexual morphs reduces with the onset of secondary mycelia and chasmothecia in late spring to early summer. The color of primary and secondary mycelia, as well as the asexual morph become yellowish, ochraceous to brownishAdvance later in the season. Branched secondary Publication hyphae and lobed hyphal appressoria present. Type: SWITZERLAND, Vaud, Gingins sur Nyon, on Triticum aestivum, 27 Jun 1998, A.
Bolay (neotype, designated here, MycoBank no.: MBT392812, TNS-F87690 = MUMH707).
Gene sequences ex-neotype: AB273542 (18S, ITS, 28S partial), AB273580 (CHS1).
- 18 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
Exsiccatae: On Elymus spp. – Constantinescu & Negrean, Herb. Mycol. Rom. 2763; Griff.,
West Amer. Fungi 164; Kari, Fungi Exs. Fenn. 22, 256, 682; Krieger, Fungi Saxon. Exs. 1669;
Krypt. Exs. 1482; Lib., Pl. Crypt. Arduenna 358; Rabenh., Fungi Eur. Exs. 477; Săvul., Herb.
Mycol. Rom. 2072; Solh., Mycofl. Saximont. Exs. 605, 606, 1119, 1319; Triebel, Microfungi
Exs. 357. Secale cereale L.– Eriksson, Fungi Paras. Scand. Exs. 487; Krieger, Fungi Saxon. Exs.
1668; Syd., Mycoth. Germ. 1088; Thüm., Herb. Mycol. Oecon. 104, 151. Triticum aestivum –
Crypt. Exs. 3346; Ellis & Everh., Fungi Columb. 505; Eriksson, Fungi Paras. Scand. Exs. 238;
Flora Olteniae Exs. 536; Jack et al., Krypt. Badens 819; Kellerm. & Swingle, Kansas Fungi
1314; Krieger, Fungi Saxon. Exs. 1216; Krieger, Schädl. Pilze Kulturgew. 27, 122; Maire,
Mycoth. Boreali-Africana 70; Petrak, Mycoth. Gen. 627; Rabenh., Herb. Viv. Mycol. 759;
Rabenh., Fungi Eur. Exs. 671; P. Sacc., Mycoth. Ital. 6147; Săvul., Herb. Mycol. Rom., Fasc. 90,
1659; Seym. & Earle, Econ. Fungi 96; Smards, Fungi Latv. Exs. 573; Thüm., Fungi Austr. Exs.
238.
Mycelia on stalks, inflorescences and leaves, amphigenous, thin to dense, effuse or in patches; primary mycelia at first white, later pigmented (Fig. 2A); primary hyphal cells about
30–55 µm long and 3–7 µm wide; secondary mycelia (onset in late spring to early summer, mostly in Jun to Jul), dense woolly to felt-like, in patches, often around chasmothecia, dingy greyish white to grey, with age turning ochraceous, greyish brown to dingy brownish, sometimes rusty reddish brown (Fig. 2A, B); secondary hyphae about 200–500 × 3–7 µm, aseptate, branched or unbranched (Fig. 2C, H), thick-walled; SH walls 1–2.5 µm; lumen later often pigmented,Advance yellowish, ochraceous to brownish. HyphalPublication appressoria nipple-shaped, occasionally lobe-shaped, 3.5–7 µm wide, single or opposite in pairs (Fig. 2G). Conidiophores 60–170 × 4–7
µm, foot-cells (20–)25–35(–40) × 5–7 µm, bulbous swelling (8–)10–14(–15) µm wide, basal
- 19 - Mycoscience: Advance Publication
septum at the junction with the supporting hypha or slightly elevated to 8 µm, 4–6 µm wide at the basal septum; 3–5 shorter cells, 12–25 µm long (Fig. 2D); conidia (20–)24–35(–40) ×
(9–)12–16(–17) µm (herbarium material), (23–)28–40(–45) × (10–)14–18(–20.5) µm (fresh material), length/width ratio 1.6–2.5(–3.1), hila (3–)4–5(–6) µm wide (Fig. 2F); apical walls thickened with depression in centre, or not thickened (SEM, Fig. 2I); germ tubes showing a specific form of germination, with two types, lateral primary germ tubes one or more, narrow, short, about 0.5 times width of conidium lacking an appressorium, appear within 1 h, followed by a broader, lateral or terminal appressorial germ tube (see Braun & Cook, 2012 for instructions), straight or somewhat flexuous, 12–50 × 2.5–4 µm, extending to 1.25–3 times the width of the conidium and with an elongated swollen tip (not shown). Chasmothecia surrounded by bristle-like secondary hyphae (Fig. 2B), immature (100–)110–180 µm diam, mature 175–
245(–260) µm diam; peridium cells obscure, irregularly polygonal, 8–20 µm diam; appendages few to numerous, in the lower half of the chasmothecium, mostly sparingly developed,
Mycelioid, simple, rarely irregularly branched, interlaced with the mycelium, short, usually shorter than the chasmothecial diam, thin-walled, hyaline to pigmented, aseptate to septate. Asci
6–30, subcylindrical to saccate, (50–)80–95(–105) × 20–45 µm, stalked or un-stalked (Fig. 2E),
(4–)8-spored (ascospores rarely developed); ascospores ellipsoid-ovoid, 20–24 × 10–14 µm, colorless to faintly pigmented.
Host range and distribution: POACEAE primarily on tribe TRITICEAE, Aegilops,
Dasypyrum, Elymus (including Hystrix), Hordeum, Secale, Triticum, also on tribe POEAE,
Milium, AdvancePhleum, occasionally on tribe BRACHYPODIEAE Publication, Brachypodium. Africa: Angola,
Canary Islands, Ethiopia, Kenya, Libya, Malawi, Morocco, South Africa, Sudan, Tanzania,
Zambia, Zimbabwe; Asia: Afghanistan, China, India, Iran, Iraq, Israel, Japan, Yemen,
- 20 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
Kazakhstan, Korea, Kyrgyzstan, Lebanon, Myanmar, Nepal, Pakistan, Russia (Siberia, Far East),
Saudi Arabia, Thailand, Turkey, Turkmenistan, Uzbekistan; Australia; Caucasus: Azerbaijan,
Armenia, Georgia; Europe: throughout the continent; New Zealand; North America: Canada,
Mexico, USA; Central & South America: Argentina, Brazil, Chile, Colombia, Ecuador, El
Salvador, Guatemala, Nicaragua, Peru, Uruguay.
Notes: De Candolle (1815) introduced Erysiphe graminis without any typification or reference to any host species. Braun (1987) searched for original collections of E. graminis in de
Candolle’s herbarium in Genève (G) up to 1815, that could serve for lectotypification purposes, but was unsuccessful. Therefore, a specimen from herbarium G was designated as neotype
[Germany, Bonn, Botanical Garden Poppelsdorf, on Triticum aestivum, 25 Jun 1869, F.A.
Körnicke [1878] (G 00122110)]. De Candolle’s (1815) work on fungi of France was part of his investigation of Central European fungi, including powdery mildews. He did not cite exact host names for E. graminis, but noted this powdery mildew was on cereal crops. This background information was the motivation for Braun’s (1987) decision to designate a specimen on Triticum aestivum from Central Europe as the neotype. However, sequence analyses of powdery mildew samples in general, and very old specimens from the 19th century in particular, were not yet possible at that time. With our current protocols, we managed to sequence the previous neotype from 1869 (G 00122110). Much to our surprise, the retrieved sequence clustered far distant from the B. graminis (s. str.) clade and instead close to B. bromi-cathartici, together with sequences obtained from Blumeria sp. on Aegilops cylindrica Host (Armenia), Dasypyrum villosum (L.) P.
CandargyAdvance (Romania), both also belonging to tribe Publication Triticeae, and Piptatherum holciforme (M.
Bieb.) Roem. & Schult. (Armenia) of tribe Stipeae (data not shown). The previous neotype designated by Braun (1987) was collected in a botanical garden. It is likely that the infection
- 21 - Mycoscience: Advance Publication
concerned was caused by an exotic powdery mildew, possibly originating from the Middle East.
Results of our sequence analyses demonstrate that Braun’s (1987) neotypification of E. graminis is in conflict with de Candolle’s (1815) original concept, focusing on Central European species, which provides strong justification for rejecting that typification. In accordance with ICN
(Turland et al., 2018, Art. 9.19 (c), Braun’s (1987) neotype is superseded here by the designation of a new neotype that is not in conflict with the protologue and stabilizes the application of E. graminis in the intended original sense.
Erysiphe graminis f. spp. tritici and secalis (Marchal, 1902) are not formal taxonomic units. Therefore, they are not ruled by the Code (ICN) and are only cited in square brackets at the end of the list of synonyms. As non-taxonomic names, formae speciales do not have type collections, i.e., status and affinity of such names cannot be verified by morphological re- examinations and gene sequencing. However, Marchal’s (1902) examinations were performed in
Central Europe, where B. graminis is the principal Blumeria species found on Secale and
Triticum species. Therefore, it is probable that Marchal (1902) had dealt with B. graminis, although host species of the Triticeae may also be infested by other Blumeria species.
Blumeria americana M. Liu, sp. nov. Fig. 3A–H.
MycoBank no.: MB 835990.
Diagnosis: Development of primary mycelium from spring to summer, also in parallel with the secondary mycelium and chasmothecia, pigmented with aging, turning yellowish, ochraceous to rusty Advancebrown, the secondary mycelium often slightlyPublication lighter color than primary mycelia and asexual morph; hyphal appressoria nipple-, lobe- or fork-shaped, 1–2 conidiophores per hyphal mother cell, foot-cells branched or unbranched.
- 22 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
Type: CANADA, Alberta, Waterton Lakes National Park, Cameron Falls, on Elymus repens
(as Agropyron repens (L.) P. Beauv.), 27 Aug 1980, J.A. Parmelee 5414 (holoype, DAOM
186037)
Gene sequences ex-holotype: MT622296 (ITS), MT633817 (Bgt-1929), MT650055 (Bgt-
4572).
Mycelia amphigenous, effuse or in patches, heavier on adaxial leaf surface; development of primary mycelia from spring to summer, persistent, often occurring in parallel with the secondary mycelium, i.e., neither inhibited nor discontinued with the onset of the development of secondary mycelium and chasmothecia, soon becoming pigmented, greyish orange, brownish orange to rusty brown (Fig. 3A, B); primary hyphae mostly branched in Y-shape, hyphal cells
27–42(–50) × 3–6(–8) µm; secondary mycelia formed from late spring or early summer to
August, in dense patches, dingy greyish white to grey; secondary hyphae attenuate to apex with obtuse tips, 4–7 µm wide, wall thick, 1–2.5 µm; SH lumen 1–3 µm, or “closed”, in part yellowish, ochraceous to golden brown (Fig. 3E). Hyphal appressoria nipple-, lobe- or fork- shaped, single or opposite in pairs, 4–5 µm wide, 4–7 µm for lobe or fork-shaped (Fig. 3I).
Conidiophores single or in pairs, 220–260 µm long; foot-cells 25–53(–66) µm long, bulbous swelling around middle 10–15 µm wide, branched or unbranched, basal septum 5–7 µm wide, at the junction with the mother cell or elevated up to 10 µm high; 1–3(–4) shorter cells, 13–30 × 4–
8(–11) µm; up to 9 conidia per chain; primary conidia broad ellipsoid-ovoid, (18–)20–31(–34) ×
10–18 µm, length/width ratio 1.5–2.5; secondary conidia broad ellipsoid, sometimes lemon- shaped, Advance14–26(–29) × 8.5–14 µm, length/width 1.5Publication–2.1(–2.9), hila 5–7 µm wide; apical walls
(SEM) with or without a thickened patch, no depression in the centre. Chasmothecia gregarious or scattered, immersed in woolly, dense secondary mycelia, semi-globose, upper surface
- 23 - Mycoscience: Advance Publication
depressed, later becoming concave, (110–)140–190(–220) µm diam; appendages sparingly developed, mycelioid; asci 18–28, oblong, ovoid, obovoid, (69–)75–100(–104) ×32–45 µm, stalk wavy or branching, 8–20 × 4.5–9 µm; ascospores not observed.
Host range and distribution: POACEAE tribe TRITICEAE subtribe Hordinae, Elymus canadensis L., E. elymoides (Raf.) Swezey (= Sitanion hystrix (Nutt.) J. G. Sm.), E. glaucus
Buckley, E. lanceolatus (Scribn. & J. G. Sm.) Gould (= Agropyron dasystachyum Ledeb.), E. repens ( Agropyron repens), E. violaceus (Hornem.) Feilberg (= Agropyron latiglume (Scribn.
& J. G. Sm.) Rydb.), Hordeum jubatum L., Leymus cinereus (Scribn. & Merr.) Á. Löve (=
Elymus cinereus Scribn. & Merr.), Pascopyrum smithii (Rydb.) Barkworth & D. R. Dewey (=
Agropyron smithii Rydb.) and Psathyrostachys juncea (Fisch.) Nevski (= Elymus junceus
Fisch.); tribe POEAE subtribe Poinae, Apera spica-venti (L.) P. Beauv. North America: Canada,
USA.
Notes: A number of samples on Elymus grouped in this species, predominantly from North
America. However, Elymus can also be infected by B. graminis s.str. and B. graminicola, so it is important to not depend solely on the host for identification. A sequence retrieved from Blumeria on a Deschampsia cespitosa (L.) P. Beauv. sample from Finland appears closely related with B. americana on the ITS tree (Supplementary Fig. S1), but was not confirmed to be a member in other analyses. Previously, Deschampsia belonged to the same subtribe (Holcinae) as Holcus, the host of B. graminicola (more information follows). Examination of additional samples on
Deschampsia cespitosa from Germany (GLM-F48875, 49967, 50142, 56429, 58758, 63460,
63463) showedAdvance the primary mycelia, conidiophores Publication and conidia turn yellowish, ochraceous to brownish (different from B. graminicola). Furthermore, a recent grass phylogenetic study
(Soreng et al., 2017) separated Deschampsia from other members of subtribe Holcinae and
- 24 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
erected a new subtribe Aristaveninae. For the time being, Blumeria on Deschampsia cespitosa can only be referred to as Blumeria sp. and is in urgent need of further genetic examination.
Blumeria avenae M. Liu & Hambl., sp. nov. Fig. 4A–I.
MycoBank no.: MB 835993.
[Erysiphe graminis f. sp. avenae E. Marchal, Compt. Rend. Acad. Sci. (Paris) 135, 211, 1902.]
Diagnosis: Development of primary mycelium from spring to autumn (Nov), sometimes even in winter (Jan), whitish to greyish white, turning yellowish, orange to brown, 1–2 conidiophores arise from the same mother cell, parallel or in different directions; hyphal appressoria mostly nipple-shaped, single, occasionally in opposite pairs.
Type: UNITED KINGDOM, England, Exeter, on Avena sativa L., 06 Feb 1948, A.S.
Boughey (holotype, DAOM 236220; isotype, IMI 24011).
Gene sequences ex-holotype: MT622301 (ITS), MT633815 (Bgt-1929), MT650063 (Bgt-
4572)
Exsiccatae: On Avena spp. – Barthol., Fungi Columb. 3151; Briosi & Cavara, Fung. Paras.
Piante Colt. Util. Ess. 174.
Mycelia on stalks and leaves, amphigenous, effuse, thin or in dense patches; primary mycelia at first whitish, later pigmented (Fig. 4A); primary hyphae with hyphal cells 2–8 µm wide; secondary mycelia develops alone or along with the asexual morph in late spring or early summer, often forming dense woolly to felt-like patches around chasmothecia, dingy greyish white toAdvance grey, with age sometimes faintly pigmented, Publication bristle-like secondary hyphae 3–6.5 µm wide, aseptate, wall 1–2 µm thick; SH lumen narrow, 1–2 µm, hyaline, occasionally becoming yellowish, ochraceous to brownish. Hyphal appressoria nipple-shaped, single or in opposite
- 25 - Mycoscience: Advance Publication
pairs, 3–6 µm wide (Fig. 4D). Conidiophores usually near or next to one septum, erect, single or in pairs (Fig. 4E–H), 60–150 × (4–)5–7(–8) µm, foot-cells (25–)30–45 × 5–6 µm, bulbous swelling 10–14 µm wide, basal septum at the junction with the mother cell or often elevated, 5–
13(–25) µm, (4–)5–7(–10) µm wide at the basal septum; (1–)2–4(–5) shorter cells, 12–35 µm long; conidia broad ellipsoid, ellipsoid, ovoid, occasionally lemon-shaped, 20–35(–40) × 10–17
µm (herbarium material), 24–38.5(–44) × 11–19 µm (fresh material), length/width ratio 1.4–
2.7(–3.3), hila (4–)5–7 µm wide (Fig. 4C); apical walls severely thickened patch with depressed centre, or not thickened (Fig. 4I). Chasmothecia 100–155 µm diam when immature, 160–200 µm diam when mature.
Host range and distribution: POACEAE tribe POEAE subtribe Aveninae, Avena. Africa:
Canary Islands, Lebanon, Libya, Morocco, South Africa, Zimbabwe; Asia: China, India, Iran,
Iraq, Israel, Turkey, Turkmenistan, Uzbekistan; Australia/Oceania: Australia, New Zealand;
Caucasus: Azerbaijan, Georgia; Europe: throughout the whole continent; North America:
Canada, Mexico, USA; Central & South America: Argentina, Brazil, Chile, Colombia,
Guatemala, Peru, Uruguay.
Notes: B. avenae appears only on Avena spp., and is closely related with B. dactylidis (see latter description). Briosi & Cavara, Fung. Paras. Piante Colt. Util. Ess. 174, noted “on Avena sativa and Hordeum vulgare L.”. The identity of the leaves in the examined duplicate preserved at HAL has been checked and proved to belong to Avena sativa.
Blumeria sp. on Koeleria pyramidata (Lam.) P. Beauv. [= K. macrantha (Ledeb.) Schult.]
(materialAdvance examined: Germany, GLM-F46754, 48469,Publication 48501, 55994, 56907, 57294, 57300,
57354, 58720) has been examined and is characterized as follows: the primary mycelium quickly becomes brownish; hyphae, conidiophores and conidia turn yellowish, ochraceous to brownish.
- 26 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
Koeleria belongs in tribe Poeae subtribe Aveninae (Soreng et al., 2017), suggesting that these infections might be caused by Blumeria avenae. However, a phylogenetic confirmation is still necessary.
Blumeria bromi-cathartici S. Takam. & M. Liu, sp. nov. Fig. 5A–H.
MycoBank no.: MB 835994.
Diagnosis: Conidia mostly oblong, 28–43 × 12–17.5 µm, long and narrow with a length/width ratio of 1.7–3.2.
Type: JAPAN, Mie, Tsu-shi, Mie University, on Bromus catharticus Vahl, 25 Apr 1995, S.
Takamatsu (holotype, TNS-F87248).
Gene sequences ex-holotype (MUMH 0117): AB000935 (ITS), AB022362 (28S),
AB033475 (18S).
Primary mycelia amphigenous, thick and persistent, white, later yellowish white to greyish yellow (4A2–4B2; Fig. 5A, B); hyphae almost straight to somewhat sinuous, 4–6(–7) um wide, branching at narrow angle, with a septum near the branching point; hyphal appressoria well- developed, nipple shaped, single (Fig. 5C). Secondary hyphae bristle-like, curved-falcate, thick- walled. Conidiophores solitary, erect, 73–119 µm long, simple, straight; foot-cells (27–)30–50(–
60) µm long bulbous swelling 9.5–12.5 µm wide, basal septum at the junction with the mother cell, basal septum 4.7–7.7 µm wide; 2–4(–5) straight shorter cells, 50–100 µm long and 7–10
µm wide, 2–8 immature conidia in chains (Fig. 5D, E); conidia oblong, occasionally limoniform,
28–43 ×Advance 12–17.5 µm, length/width ratio 1.7–3.2, Publication hila 5.0–7.7 µm wide (Fig. 5F), producing germ tube on the shoulder, germ tubes Blumeria type (Fig. 5G); apical walls (SEM) mostly not thickened, occasionally with a slightly thickened patch (Fig. 5H). Chasmothecia not observed.
- 27 - Mycoscience: Advance Publication
Host range and distribution: POACEAE subfam. POOIDEAE tribe BROMEAE, Bromus catharticus. Asia, Japan. North America, United States
Notes: Inuma et al. (2007) revealed three lineages on Bromus using multi-locus phylogenetic analyses. This species, representing the lineage specific on B. catharticus and including two samples from Japan and one from United States (CA), was clearly separated from a Eurasian species, B. bulbigera (see next species described) which was on various Bromus spp. The third lineage was a sequence retrieved from a specimen collected in Argentina (MUMH2192), had an uncertain affinity to other lineages, and might represent a different species. Morphologically, B. bromi-cathartici is characterized by having longer conidia (mostly oblong), and restricted host ranges. Amano (1986) recorded B. graminis on Bromus catharticus from Europe (Germany),
North America (USA), and South America (Argentina, Brazil). In an ITS tree with extended samples (data not shown), several sequences retrieved from Blumeria on several hosts belonging to Triticeae, i.e. Aegilops cylindrica (Armenia), Dasypyrum villosum (Romania), Triticum aestivum (Germany, historic sample from the 19th century, collected in a botanical garden) and a single host species in Stipeae, i.e. Piptatherum holciforme (Romania), cluster close to B. bromi- cathartici. The status of those collections remains unclear. They can currently only be referred to as Blumeria sp. They seem to represent a distinct lineage and undescribed species, but further morphological and phylogenetic analyses are required.
Blumeria bulbigera (Bonord.) M. Liu & U. Braun, comb. nov. Fig. 6A–J.
MycoBankAdvance no.: MB 835998. Publication
- 28 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
Basionym: Torula bulbigera Bonord., in Rabenh., Fungi Eur. Exs. (Klotzschii Herb. Viv. Mycol.
Continuatio, Ed. Nova, Ser. Sec.), Cent. 2: no. 175, 1860 [also in Bot. Zeitung 18: 175, 1860;
Flora 43: 748, 1860].
≡ Oidium bulbigerum (Bonord.) Sacc. & Voglino, in Sacc., Syll. Fung. 4: 47, 1886.
= Botrytis simplex monilis Alb. & Schwein., Consp. fung. lusat.: 363, 1805.Type not
designated (“in foliis culmisque, … graminum (Bromi mollis etc.). Neotype (designated
here, MycoBank no.: MBT392810): Germany, Saxony, Königstein, on Bromus hordeaceus
L. (= B. mollis L.), 28 Jun 1905, W. Krieger, Fungi Saxon. Exs. 1921 (HAL, s.n.).
Isoneotypes: Krieger, Fungi Saxon. Exs. 1921 (e.g., B, BPI 562907, M-13677, etc.).
= Oidium monilioides var. ochraceum Thüm., Fungi Austr. Exs. 1084, 1874. Lectotype
(designated here, MycoBank no.: MBT392811): Czech Republic, Bohemia, Teplice
(Tepliz), on Bromus hordeaceus, 1873, F. v. Thümen, Thüm., Fungi Austr. Exs. 1084
(HAL, s.n.). Isolectotypes: Thüm., Fungi Austr. Exs. 1084 (e.g., BPI 409682, ILL 85997).
Oidium ochraceum (Thüm.) Mussat, in Saccardo, Syll. fung. (Abellini) 15: 231, 1901.
[Erysiphe graminis f. sp. bromi E. Marchal Compt. Rend. Acad. Sci. (Paris) 135, 212, 1902.]
Diagnosis: Development of the primary and secondary mycelium from spring to late summer, or to autumn (Oct); primary mycelia and asexual morph turning pale yellow to ochraceous with age; ovoid swellings may present in the middle or at the end of primary hyphae; secondary hyphae multi-septate, lumen yellowish to ochraceous with age. TypeAdvance: GERMANY, Rhine-Westphalia (Guestphalia), Publication Herford, “in foliis graminum” (Bromus hordeaceus), Rabenh., Fungi Eur. Exs., Cent 2, no. 275 (lectotype, designated here,
MycoBank no.: MBT392798, B, s.n.; isolectotypes, Rabenh., Fungi Eur. Exs., Cent 2, no. 275
(e.g., L9102521067, HAL s.n). FINLAND, Regio aboënsis, Uusi-Kaupunki, on Bromus
- 29 - Mycoscience: Advance Publication
hordeaceus subsp. hordeaceus (= B. mollis), 13 Aug. 1957, L. & K. Roivainen (epitype, designated here, MycoBank no.: MBT 392801, DAOM 82541); gene sequences ex-epitype
MT622280 (ITS).
Exsiccatae: On Bromus spp. – Bucholtz, Fungi Ross. Exs., Ser. A, 84; Griff., West Amer.
Fungi 101; Krieger, Fungi Saxon. Exs. 1921; Rabenh., Fungi Eur. Exs. 81, 175; Săvul., Herb.
Mycol. Rom. 1871, 1872, 2273; Solh., Mycofl. Saximont. Exs. 607.
Mycelia on stalks and leaves, amphigenous, thin to dense, effuse or in patches
(inconspicuous on B. hordeaceus, only seen in close-up); primary mycelia at first white, often turning pale yellow, ochraceous with age, in patches or effuse thin layers (Fig. 6A); primary hyphae cells 3–7 µm wide, occasionally with swollen portions, up to 10 µm wide (Fig. 6F); secondary hyphae 4–7 µm wide, mostly aseptate, occasionally 2–3 septa (Fig. 6H), wall 1–2.5
µm thick; SH lumen narrow, 1–2 µm, or “closed”, hyaline, sometimes slightly pigmented, yellowish white to pale yellow (3A2–3A3), ochraceous. Conidiophores erect, mostly close to one septum, occasionally in centre, 80–130 × 5–6 µm, foot-cells 25–45 × 5–6 µm, bulbous swelling 9–14 µm wide, basal septum at the junction with the supporting hypha or slightly elevated, to 5 µm, 5–6(–8) µm wide at the septum; 2–4 shorter cells, 10–30 µm long (Fig. 6E); conidia ellipsoid, broad ellipsoid, ovoid, to limoniform, 25–32 × 12–16 µm (herbarium material),
27–35 × 13–18.5 µm, hila 3–5 µm wide, length/width ratio 1.5–2.5 (Fig. 6G); apical walls with a thickened ring, or thickened depressed centre (SEM; Fig. 6I, J). Development of chasmothecia from spring to summer, loosely surrounded by secondary hyphae, or exposed (Fig. 6B, C), 100–
160 µm Advancediam when immature, 150–200 µm when Publication mature; asci ovoid with a short cylindrical stalk 10–16 × 5–7 µm (Fig. 6D); ascospores not observed.
- 30 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
Host range and distribution: POACEAE subfam. POOIDEAE tribe Bromeae, Bromus spp.
Africa: Canary Islands, Morocco, West Sahara; Asia: Afghanistan, China, Iran, Iraq, Israel,
Jordan, Kazakhstan, Korea, Russia – Siberia, Syria, Turkey, Turkmenistan, Uzbekistan;
Australia; Caucasus: Armenia, Azerbaijan, Georgia; Europe: widespread in the whole continent;
New Zealand; North America: Canada, USA; South America: Argentina, Chile.
Notes: Blumeria bulbigera seems to be confined to Bromus species and distributed in
Eurasia and North America. The broad distribution can probably be explained by a co- distribution with the wide synanthropic occurrence of several Bromus species as neophytes. The records of B. graminis s. lat. on diverse Bromus species (Amano, 1986; Braun, 1995; https://nt.ars-grin.gov/fungaldatabases/specimens/Specimens.cfm) need to be confirmed by molecular methods and morphological re-examination.
Blumeria dactylidis M. Liu & Hambl., sp. nov. Fig. 7A–K.
MycoBank no.: MB 835995.
= Erysiphe graminis f. dactylidis-glomeratae Sacc., Mycoth. Ven. 606, 1876.
= Erysiphe graminis f. dactylidis Jacz., Karm. Opred. Grib., Vip. 2. Muchn.-rosj. griby
(Leningrad): 149, 1927.
= Erysiphe graminis f. alopecuri Jacz., Karm. Opred. Grib., Vip. 2. Muchn.-rosj. griby
(Leningrad): 143, 1927.
= Erysiphe graminis f. anthoxanthi Jacz., Karm. Opred. Grib., Vip. 2. Muchn.-rosj. griby
(Leningrad):Advance 143, 1927. Publication
[Erysiphe graminis f. sp. dactylidis Okuda et al., Ann. Phytopathol. Soc. Japan 51: 615, 1985.]
- 31 - Mycoscience: Advance Publication
Diagnosis: Primary mycelia and asexual morph turning yellowish, ochraceous to brownish, lasting until autumn (early Oct) in parallel with the secondary mycelium and chasmothecia; secondary mycelia white to greyish white, or orange grey, much lighter than primary mycelia, aseptate; hyphal appressoria nipple- or lobe-shaped, single; conidial apical walls not thickened.
Type: CANADA, British Columbia, North Saanich, on Dactylis glomerata L., 12 Apr 1934,
W. Jones, as ‘W.J.’ (holotype, DAOM 118220).
Gene sequences ex-holotype: MT622286 (ITS), MT633919 (CHS1), MT633812 (Bgt-1929),
MT650032 (Bgt-4572).
Exsiccatae: On Dactylis spp. – Mäkinen, Fungi Exs. Fenn. 682; Sacc., Mycoth. Venet. 606;
Săvul., Herb. Mycol. Rom. 2272; Vill, Fungi Bavar. 962.
Mycelia on stems and leaves, mainly on adaxial leaf surface, or amphigenous, thin to dense, effuse or in patches, primary mycelia along with asexual morph at first white, turning pale yellow (4A2), ochraceous to brown (5A2–5E4; Fig. 7A, B); secondary mycelia development starts mostly in Jun to Jul, lasting until late fall in parallel with primary mycelia and asexual morphs, dingy greyish white to grey, turning ochraceous to pale dingy, orange grey with age
(Fig. 7A); primary hyphal cells 3–6 µm wide, occasionally with swollen portions, up to 9 µm wide; hyphal appressoria nipple-, sometimes lobe-shaped, 3–7 µm wide, lobe-shaped up to 10
μm wide (Fig. 7E); secondary hyphae about 500 μm long, in dense woolly to felt-like patches around chasmothecia (Fig. 7C, D), aseptate, wall 1–2 µm thick, central lumen narrow, 0–2 µm, hyaline, lumen usually not pigmented; conidiophores single, erect, 65–135 × 5–6 µm; foot-cells
(25–)30–Advance50 × 5–6 µm, bulbous swelling 9–13 µmPublication wide, basal septum at the junction with the supporting hypha or slightly elevated up to 8 µm, 4–7 µm wide at the septum; 3–4 shorter cells,
12–25 µm long (Fig. 7F–H); conidia ellipsoid, broad ellipsoid, ovoid, dolliform, rarely lemon-
- 32 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
shaped (Fig. 7I), 21–35 × 11–15 µm (herbarium material), 23–38 × 12–18 µm (fresh material), length/width ratio 1.5–2.6(–2.9), hila 4–7 µm wide; conidial apical walls not thickened (SEM;
Fig. 7K). Chasmothecia (100–)140–180 µm diam when immature, 160–245 µm diam when mature; asci obovoid-clavate to saccate, (45–)60–90 × 25–40 µm, stalks very short, inconspicuous (Fig. 7J); ascospores not observed.
Host range and distribution: POACEAE tribe POEAE subtribe Dactylidinae, Dactylis glomerata s. lat. as principal host, less frequently on subtribe Anthoxanthinae, Anthoxanthum odoratum L. and A. aristatum Boiss., occasionally subtribe Loliinae, Festuca pratensis Huds. and Lolium multiflorum Lam., subtribe Poinae, Phleum sp.; tribe BROMEAE, Bromus; tribe
TRITICEAE subtribe Hordinae, Hordeum. North Africa: Morocco; Asia: Israel, Japan,
Kazakhstan, Korea, Kyrgyzstan, Russia – Siberia, Turkey, Turkmenistan, Uzbekistan; Caucasus:
Armenia, Azerbaijan, Georgia; Europe: throughout the whole continent; North America: Canada,
USA.
Notes: The principle host genus of this species is Dactylis (tribe Poeae) with Dactylis glomerata as the main host, but it can also be found on other genera in the same tribe, i.e,
Anthoxanthum, Festuca, and Phleum. Erysiphe graminis f. sp. dactylidis, introduced by Oku,
Yamashita, Doi, and Nishihara (1985) based on inoculation experiments with Dactylis glomerata performed in Japan, undoubtedly refers to Blumeria dactylidis. A wide array of grasses from numerous genera were included in their examinations, but Blumeria on Dactylis glomerata in
Japan was strictly confirmed to this host species.
ForAdvance Blumeria on Festuca gigantea (L.) Vill. Publication (material examined: Germany, GLM-F54303,
63457, 79631, 90974, 99586, 96672, 102932), the primary mycelium quickly becomes ochraceous to pale brownish. Festuca gigantea is a broad-leaved species of Festuca s. lat. This
- 33 - Mycoscience: Advance Publication
genus belongs in tribe Poeae subtribe Loliinae, which is close to subtribe Dactylidinae (Soreng et al., 2017), suggesting that B. dactylidis might be the causal agent of infections on F. gigantea.
However, a phylogenetic confirmation is necessary. BPI 562975 on F. pratensis from the Czech
Republic and HAL 000025 F on F. gigantea from Germany belong to B. dactylidis based on the
Bgt-1929 tree. The position of BPI 562975 was also confirmed by Bgt-4572 and CHS1 trees.
However, Festuca spp. can also be infested by B. graminicola (see notes under this species).
A rarer case is that two samples on Bromus from Germany (HAL 000027 F) and USA (BPI
562894) were also grouped in this clade, the former on Bgt-1929 and ITS tree, the latter on Bgt-
4572, indicating the host range potential is across different tribes.
Blumeria graminicola M. Liu & Hambl., sp. nov. Fig. 8A–K.
MycoBank no.: MB 835996.
= Erysiphe graminis f. aperae Jacz., Karm. Opred. Grib., Vip. 2. Muchn.-rosj. griby
(Leningrad): 143, 1927.
= Erysiphe graminis f. milii Jacz., Karm. Opred. Grib., Vip. 2. Muchn.-rosj. griby
(Leningrad): 152, 1927.
= [Erysiphe graminis f. sp. poae E. Marchal, Compt. Rend. Acad. Sci. (Paris) 135, 210-212,
1902.]
Diagnosis: Development of primary mycelium and asexual morph until winter (Jan/Feb), not inhibitedAdvance with the onset of secondary mycelium andPublication chasmothecia (May); primary and secondary mycelia and asexual morph whitish to greyish white, not distinctly pigmented with age; secondary hyphae aseptate; hyphal appressoria nipple-shaped, lobe-shaped, single; conidial apical walls severely thickened depressed in centre.
- 34 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
Type: CANADA, Ontario, Ottawa, Central Experiment Farm, Lawn, on Poa pratensis L., 02
Aug 1974, J. A. Parmelee (holotype, DAOM 159510).
Gene sequences ex-holotype: MT633954 (CHS1), MT633820 (Bgt-1929), MT650048 (Bgt-
4572).
Exsiccatae: On Apera spica-venti – Jack et al., Krypt. Badens 829; Krieger, Fungi Saxon.
Exs. 1217; Syd., Mycoth. Germ. 1529; Thüm., Fungi Austr. Exs. 1244. On Milium effusum L.:
Lundell & Nannf., Fungi Exs. Suec. 1470. On Poa spp. – W.B. Cooke, Mycobiota Mt. Shasta 26;
Griff., West Amer. Fungi 102; Liro, Mycoth. Fenn. 623; Ravenel, Fungi Amer. Exs. 308;
Ravenel, Fungi Carol., Fasc. II, 85; Săvul., Herb. Mycol. Rom., Fasc. 1777, 1875; Schneider,
Herb. Schlesischer Pilze 920; Solh., Mycofl. Saximont. Exs. 1121, 1318; Thüm., Herb. Mycol.
Oecon. 123; Thüm., Mycoth. Univ. 257; Vill, Fungi Bavar. 961.
Primary mycelia on leaves, amphigenous, occasionally on stalks, thin to dense, effuse or in patches, development from spring (Apr/May) to autumn (Nov), sometimes even in winter
(Jan/Feb), neither inhibited nor discontinued with the onset of secondary mycelium and chasmothecia (May); whitish to greyish white, at most faintly yellowish, not distinctly pigmented with age (Fig. 8A, B); primary hyphal cells 2–6 µm wide; hyphal appressoria nipple-shaped, occasionally lobe-shaped, single or in opposite pairs (Fig. 8G); secondary hyphae 3–7 µm wide, with 1–2 septa (Fig. 8E), thick-walled, wall 1–2 µm thick; central lumen narrow, 0–2 µm, usually hyaline. Conidiophores single or in pairs, close to one septum, erect, 70–150 × 5–7 µm
(Fig. 8F, H), mother cells occasionally swollen up to 12 µm wide, foot-cells (20–)25–45(–55) ×
5–7 µm,Advance bulbous swelling (8–)9–13(–14) µm wide,Publication basal septum at the junction with the supporting hypha or slightly elevated up to 5(–10) µm, 4–7 µm wide at the septum; (2–)3–5(–7) shorter cells, 12–25 µm long; conidia broad ellipsoid to lemon-shaped, 19–33 × 10–15 µm
- 35 - Mycoscience: Advance Publication
(herbarium material), 29–35 × 11–17.5 µm (fresh material), hila 4–6 µm wide (Fig. 8I); apical walls severely thickened depressed in centre (Fig. 8J, K). Chasmothecia 100–150 µm diam when immature, 140–200 µm when mature; appendages sparse, Mycelioid, with a basal septum (Fig.
8C); asci subglobose to ovoid, stalk inconspicuous, or short, branched or unbranched; ascospores not observed (Fig. 8D).
Host range and distribution: POACEAE tribe POEAE subtribe Poinae, Apera spica-venti,
Poa spp. as principle hosts, but also on subtribe Agrostidinae, Agrostis sp., Polypogon monspeliensis (L.) Desf., subtribe Alopecurinae, Alopecurus geniculatus L., Beckmannia spp., subtribe Anthoxanthinae, Anthoxanthum nitens (= Hierochloe odorata), subtribe Coleanthinae,
Puccinellia spp, subtribe Dactylidinae, Dactylis glomerata, subtribe Holcinae, Holcus lanatus, subtribe Loliinae, Festuca spp, subtribe Miliinae, Milium effusum; tribe TRITICEAE subtribe
Hordeinae, Elymus sp., subtribe Triticinae, Thinopyrum intermedium (Host) Barkworth & D. R.
Dewey, Triticum aestivum (only one sample from Australia); tribe BROMEAE, Bromus spp.; tribe MELICEAE, Melica subulata (Griseb.) Scribn. Africa: Morocco; Asia: Afghanistan, China,
India, Iran, Israel, Japan, Kazakhstan, Korea, Kyrgyzstan, Mongolia, Russia (Siberia, Far East),
Turkey, Turkmenistan, Uzbekistan; Caucasus: Armenia, Azerbaijan, Georgia, Europe: throughout the continent; New Zealand; North America: Canada, USA; South America:
Argentina.
Notes: All the studied samples on Poa spp. grouped in this clade, agreeing with the previous recognition of f. sp. poae by Marchal (1902), based on examinations of central European specimens.Advance A remarkable feature of this species isPublication its persistent white color of mycelia and asexual morphs throughout the growing season. Blumer (1967) already noted the difference between the white mycelium of the powdery mildew on Poa spp. and the pigmented mycelia on
- 36 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
other hosts. Poa is the largest grass genus with around 500 species distributed in cool temperate regions (Kellogg, 2015), representing a large pool of genetic diversity. It is very likely that this large genetic diversity set the stage for B. graminicola to also diversify and adapt to different host species in Poa and also further to a wider range of host genera. The DNA sequence analyses demonstrate B. graminicola has the highest nucleotide diversities for all four loci compared with other species (data not shown). Chasmothecia are commonly formed on Apera spica-venti
(development beginning in May).
Species of Festuca are hosts of several Blumeria spp., including B. dactylidis and B. graminicola. In an examined specimen on Festuca heterophylla Lam. from Germany (GLM-
F59650), the primary mycelium remains white, suggesting an identity of B. graminicola. This observation is supported by results of sequence analyses of collections from Germany on
Festuca gigantea (BPI 562974) and USA on F. idahoensis Elmer (BPI 562965) that belong to B. graminicola on Bgt-1929, Bgt-4572, and CHS1 tress. Several collections of B. graminis s. lat. from Germany, Sachsen-Anhalt, on Alopecurus myosuroides Huds. (GLM-F48858, 50092,
54764, 57282, 94380), the primary mycelium and the asexual morph remain whitish as in B. graminicola, agreeing with the grouping of HAL 000022 F (on A. geniculatus) in B. graminicola clade on Bgt-1929 tree. In addition, specimens on Alopecurus could also belong to B. hordei (see
BPI 562851 on Bgt-4572 tree).
BlumeriaAdvance hordei M. Liu & Hambl., sp. nov. Publication Fig. 9A–I. MycoBank no.: MB 835997.
= Erysiphe graminis f. hordei-culti Jacz., Karm. Opred. Grib., Vip. 2. Muchn.-rosj. griby
(Leningrad): 150, 1927.
- 37 - Mycoscience: Advance Publication
= Erysiphe graminis f. hordei-spontanei Jacz., Karm. Opred. Grib., Vip. 2. Muchn.-rosj. griby
(Leningrad): 151, 1927.
[Erysiphe graminis f. sp. hordei E. Marchal Compt. Rend. Acad. Sci. (Paris) 135, 211, 1902.]
Diagnosis: Development of primary mycelia and asexual morph from spring to summer, occasionally up to Sep, not inhibited with the onset of the formation of secondary mycelium and chasmothecia; primary mycelia, conidiophores and conidia turning greyish brown with age in summer; secondary hyphae aseptate; hyphal appressoria nipple-shaped, mostly in opposite pairs; one or two conidiophores per mother cells.
Type: CANADA, Quebec, Stat. expér. fédérale, Ste-Anne-de-la-Pocatière, on Hordeum vulgare, 8 Aug 1940, SAP 372 (holotype, DAOM 18154).
Gene sequences ex-holotype: MT622276 (ITS), MT633825 (Bgt-1929), MT650018 (Bgt-
4572).
Exsiccatae: On Hordeum spp. – Barthol., Fungi Columb. 3427, 4726; Flora Olteniae Exs.
118, 535; Griff., West Amer. Fungi 165; Kellerm. & Swingle, Kansas Fungi 1133; Linh., Fungi
Hung. 80; P. Sacc., Mycoth. Ital. 1473; Săvul., Herb. Mycol. Rom. 89, 1873, 1874, 3205; Thüm.,
Herb. Mycol. Oecon. 252.
Mycelia on stalks and leaves, amphigenous, thin to dense, effuse or in patches; primary mycelium white, becoming pigmented with age (in summer), greyish yellow (4B4) to greyish brown (5D3), not inhibited by the onset of secondary mycelia in late spring or early summer
(mostly in May to Jun); secondary mycelia dingy greyish white to grey, with age sometimes faintly pigmentedAdvance to greyish orange (5B2–5B3 ; Fig.Publication 9A, B). Primary hyphal cells 3–6 µm wide; hyphal appressoria nipple-shaped, 3–6 µm wide, mostly in opposite pairs (Fig. 9H); secondary hyphae mostly aseptate (one septum near the base), thick-walled, wall 1–2 µm thick; central
- 38 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
lumen narrow, 0–2 µm (Fig. 9F). Conidiophores, single or occasionally in pairs, erect, 60–120 ×
5–7 µm, foot-cells 25–45 × 5–7 µm, bulbous swelling 10–15 µm wide, basal septum at the junction with the supporting hypha or slightly elevated up to 5 µm, 5–7 µm wide at the septum;
2–3 shorter cells, 10–25(–30) µm long (Fig. 9D, E); conidia broad ellipsoid, oblong, dolliform, ovoid, rarely limoniform, 20–32 × 11–15 µm (herbarium material), 23–38 × 12–18 µm (fresh material), length/width ratio 1.5–2.6(–2.9), hila 4–6 µm wide (Fig. 9G); apical walls with or without thickened patch, depressed in centre (Fig. 9I). Chasmothecia 125–185 µm diam when immature, 170–285 µm diam when mature; asci broad ellipsoid, ovoid, with short stalks (Fig.
9C); ascospores not observed.
Host range and distribution: POACEAE tribe TRITICEAE subtribe Hordinae, Hordeum spp., including H. murinum L., H. vulgare, occasional samples on Leymus condensatus (J. Presl) Á.
Löve, Pseudoroegneria spicata (Pursh) Á. Löve; tribe POEAE subtribe Agrostidinae, Agrostis exarata Trin., Alopecurus aequalis Sobol.; tribe BROMEAE, Bromus spp. Africa: Afghanistan,
Angola, Canary Islands, Egypt, Ethiopia, Jordan, Kenya, Lebanon, Libya, Morocco,
Mozambique, Saudi Arabia, South Africa, Sudan, West Sahara; Asia: China, India, Iran, Iraq,
Israel, Japan, Kazakhstan, Korea, Kyrgyzstan, Nepal, Pakistan, Russia – Siberia, Turkey,
Turkmenistan, Uzbekistan, Yemen; Australia; Caucasus: Armenia, Azerbaijan, Georgia; Europe: throughout the whole continent; New Zealand; North America: Canada, Mexico, USA; South
America: Argentina, Brazil, Chile, Colombia, Ecuador, Uruguay.
Notes: The clade corresponding to this species included samples mainly on Hordeum murinumAdvance L. and H. vulgare, but also sporadic samplesPublication on other genera. The identification of the host was as recorded on the specimen label, not confirmed by DNA analyses, therefore, the possibility that the host was misidentified cannot be ruled out. Reversely, not all samples on
- 39 - Mycoscience: Advance Publication
Hordeum spp. belong to B. hordei, they could belong to B. americana, B. graminis s. str. as well as B. dactylidis. The result supports the recognition of five special forms in barley powdery mildew (B. graminis f. sp. hordei) by Mains and Dietz (1930).
3.4. Key to Blumeria spp. based on morphology and host preference
1a. Primary mycelium and asexual morph remaining whitish to greyish white, at most somewhat
yellowish or pale ochraceous with age, but never becoming brown ...... 2
1b. Primary mycelium soon or at least with age becoming pigmented, yellowish, ochraceous to
finally brown ...... 4
2a. Hitherto only known on Bromus catharticus and Bromus sp. from Asia (Japan) and North
America (USA); only primary mycelium and asexual morph known; conidia relatively long,
28–43 × 12–17.5 µm, with a length/width ratio of 1.7–3.2 ...... Blumeria bromi-cathartici
2b. On other hosts; forming primary and secondary mycelium; conidia shorter, (20–)24–35(–40)
µm long, length/width ratio 1.6–2.5(–3.1) ...... 3
3a. Formation of the primary mycelium and asexual morph from spring (April/May) to autumn
(September to November), sometimes even in winter; on Apera, Milium, and Poa spp.,
occasionally on additional hosts ...... Blumeria graminicola
3b. Formation of the primary mycelium from spring to summer, occasionally September,
sometimes remaining light colored; on Hordeum spp...... Blumeria hordei
4a. Bristle-like curved-falcate hyphae of the secondary mycelium remaining colorless; on
DactylisAdvance spp. (occasionally also on other hosts, Publication such as Alopecurus aequalis, Anthoxanthum
odoratum, and Lolium multiflorum) ...... Blumeria dactylidis
- 40 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
4b. Bristle-like curved-falcate hyphae of the secondary mycelium usually pigmented with age,
yellowish, ochraceous, golden brown to brownish ...... Complex of morphologically
indistinguishable species, in part with overlapping hosts ranges (identification with certainty
only possible by means of sequence analyses):
Mainly on Avena spp...... Blumeria avenae
Mainly on Bromus spp...... Blumeria bulbigera
Mainly on Hordeum spp., occasionally on Agrostis, Alopecurus, Bromus, Leymus,
Pseudoroegneria, Triticum ...... Blumeria hordei
Mainly on host belonging to Poaceae tribe Triticeae, occasionally on Brachypodium, Milium,
Phleum ...... Blumeria graminis s. str.
Mainly on hosts in tribe Triticeae, including Aegilops, Elymus, Hordeum, Pascopyrum,
Psathyrostachys, occasionally on Apera ...... Blumeria americana
3.5. Formae incertae sedis
The following names were introduced as mere host/substrate formae, in almost all cases without description. These formae are nevertheless valid names (the different hosts, which are eponymous, are considered to be sufficient as diagnostic information for formae in plant pathogenic fungi). However, the clarification of the affiliation of these formae requires typifications of these names and corresponding ex-type sequence data. Several of the host genera concernedAdvance belong to the host range of more than Publicationone Blumeria species.
- 41 - Mycoscience: Advance Publication
Erysiphe graminis f. agrostidis Jacz., Karm. Opred. Grib., Vip. 2. Muchn.-rosj. griby
(Leningrad): 143, 1927.
Note: Two samples on Agrostis sp. were included in analyses. One from Canada (DAOM
150568) was determined as B. graminicola, another from USA (BPI 859594) as B. hordei.
Erysiphe graminis f. beckmanniae Jacz. (l.c.: 144).
Note: two samples on Beckmannia spp. from Canada (DAOM 152932, DAOM 217878) grouped in B. graminicola.
Erysiphe graminis f. brizae Jacz. (l.c.: 490).
Erysiphe graminis f. bromi-brachypodii Jacz. (l.c.: 145).
Erysiphe graminis f. cynosuri Jacz. (l.c.: 149).
Erysiphe graminis f. deschampsiae Jacz. (l.c.).
Note: The sequences of a sample on Deschampsia from Finland (DAOM 82542) did not belong to any of the described species.
Erysiphe graminis f. gaudiniae Jacz. (l.c.: 490).
Erysiphe graminis f. holci Jacz. (l.c.: 150).
Note: One sample on Holcus lanatus from Germany (BPI 562984) belonged to B. graminicola on Bgt-4572 tree, another from Romania (BPI 562983) had no affinity to any described species.
Erysiphe graminis f. lepturi Jacz. (l.c.).
Erysiphe graminis f. moliniae Jacz. (l.c.).
ErysipheAdvance graminis f. phalaridis Jacz. (l.c.). Publication
Erysiphe graminis f. phlei Jacz. (l.c.).
- 42 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
Note: two samples on Phleum spp. from Russia (BPI 563065, HAL 000006 F) grouped in B. dactylidis on the Bgt-4572 and Bgt-1929 trees, respectively; DAOM 169330 from Canada in B. graminis s.str.
Erysiphe graminis f. sacchari Jacz. (l.c.: 153).
Erysiphe graminis f. sesleriae Jacz. (l.c.: 154).
Erysiphe graminis f. setariae Jacz. (l.c.).
Erysiphe graminis f. atropidis Lavrov, Trudy Tomsk. Gosud. Univ. Kuibysheva, Ser. Biol.,
110(4): 193, 1951.
Erysiphe graminis f. cleistogenis Bunkina, Novosti Sist. Nizsh. Rast 10: 81, 1973.
Erysiphe graminis f. stipae Bunkina & Nelen, in Bunkina, Komarovskie Chteniya (Vladivostok)
21: 88, 1974.
Erysiphe graminis f. diarrhenae Bunkina, Novosti Sist. Nizsh. Rast. 1967: 175, 1967.
3.6. Unresolved names
Acrosporium monilioides Nees, Syst. Pilze: 53, 1817.
≡ Oidium monilioides (Nees) Link, Sp. pl. 4, 6(1): 122, 1824.
≡ Oidium monilioides var. album Link, in Willdenow, Sp. pl. 4, 6(1): 122, 1824.
≡ Torula acrosporium Corda, in Sturm, Deutschl. Flora, III. Abt. Die Pilze Deutschlands, 8.
Heft: 75, Nürnberg 1829, nom. illeg. (nom. superfl., Art. 52.1).
Type: onAdvance Dinebra retroflexa (Vahl) Panz., on a pottedPublication plant (not yet located, probably not preserved).
- 43 - Mycoscience: Advance Publication
Notes: Dinebra belongs to Poaceae, tribe Cynodonteae subtribe Elsininae. The description of A. monilioides was based on an infected potted exotic grass. The infection could be by one of the described Blumeria species through host jumping.
Monilia hyalina Fr., Observ. mycol. 1: 210, 1815. Lectotype (designated here, MycoBank no.:
MBT392802): Fries, Observ. mycol. 1: Tab. III, fig. 4 (a–d).
≡ Acrosporium hyalinum (Fr.) Sumst. [as ‘hyalina’], Mycologia 5(2): 58, 1913.
Type: “in culmis gramineis” (not preserved).
Note: Fries (l.c.) published a brief description and illustration, and cited Acharius as the collector. Herbarium Acharius housed in the University of Helsinki (H) was searched, but the original material of M. hyalina could not be located (O. Miettinen, pers. comm.). Neither could
Uppsala University Museum of Evolution (UPS) locate the type material. Due to the paucity of the information in his original description, the host identity is unknown and it is unclear whether
Fries found this fungus on living or dead grass stems. Link (1824) was the first author who reduced M. hyalina to synonymy with O. monilioides, and Sumstine (1913) reallocated the former name to Acrosporium and considered it the asexual morph of E. graminis. Braun and
Cook (2012) followed this treatment and cited M. hyalina as synonym of B. graminis. However, this synonymy is doubtful. The ecology of M. hyalina is also unclear. It would also be possible that Fries (l.c.) observed and illustrated a saprobic hyphomycete on dead stems of grasses. His description (“articulis subgloboso-ovatis”) and illustration are not quite in concordance with the charactersAdvance of the asexual morph of B. graminis , whichPublication is characterized by having ellipsoid-ovoid to limoniform conidia (never subglobose ones). The original illustration published by Fries (l.c.) is part of the original material and the only element available for lectotypification. However, as
- 44 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
long as type material of M. hyalina is not available and cannot be re-examined, the status and the affinity of this name remain elusive and prevent its use.
Torula papillata Bonord., Bot. Zeitung (Leipzig) 19: 195, 1861.
≡ Oidium papillatum (Bonord.) Sacc. & Voglino, in Sacc., Syll. Fung. 4: 46, 1886. Lectotype
(designated here, MycoBank no.: MBT392803): Bonorden, Bot. Zeitung (Leipzig) 19: Taf. VIII,
Fig. 10 (a–e), 1861.
Notes: Bonorden (1861) described and illustrated Torula papillata with conidiophores attenuated towards an unswollen base, giving rise to conidia with papilloid apex and base
(“utrimque subpapillatis”), formed singly or in chains. These characters are unusual and not in accordance with B. graminis s. lat. Bonorden (l.c.) was a good observer and provided exact drawings, as can be seen in his excellent drawing of the asexual morph of B. graminis s. lat. published as Oidium bulbigerum. Thus, it can be ruled out that he had overlooked existing swellings of the conidiophores in the case of T. papillata. Bonorden (l.c.) did not give any further details as to the host and ecology of this species. It is even possible that he had dealt with a saprobic hyphomycete on a dead grass. The generic affinity of this species is quite unclear, although it was reallocated to Oidium by Saccardo and Voglino (in Saccardo, 1886) and accepted as a synonym of B. graminis (≡ Erysiphe graminis) in Braun (1987) and Braun and Cook (2012).
Type material of T. papillata is not preserved, so that Bonorden’s original drawing represents the only original material available for lectotypification. Another collection, preferably new material with a cultureAdvance and ex-culture sequence data, is necessaryPublication for epitypification to elucidate the generic affinity of this species.
- 45 - Mycoscience: Advance Publication
Oidium monilioides var. flavicans Link, in Willdenow, Sp. pl. 4, 6(1): 123, 1824.
Type: Germany, Berlin (“in foliis Graminum in Germania. Lect. Berolini”), J.H.F. Link (not preserved).
Notes: Type material is not preserved in Berlin (herb. B, Robert Lücking, curator for cryptogams, pers. comm.), and Link (l.c.) did not give any details as to the host range. The mycelium of several Blumeria species turns yellowish, ochraceous to brownish with age.
4. Discussion
Powdery mildew infections on cereal crops and grasses (Poaceae) have been treated as belonging to a single species since de Candolle’s (1815) first introduction of the name Erysiphe graminis. Subsequent landmark monographs of powdery mildews (Erysiphaceae) maintained this concept (Salmon, 1900; Braun & Cook, 2012) despite the perception of morphological differences between collections on various hosts (Blumer, 1967) and recognition of biological races (formae speciales) within E. graminis (e.g., Marchal, 1902; Oku et al., 1985). Multi-gene phylogenetic analyses of B. graminis (s. lat.) on a relatively broad sampling of hosts (Inuma et al., 2007) revealed nine lineages of B. graminis, and this motivated our present phylogenetic- taxonomic revision. The multi-gene analyses in this expanded study, for an even wider range of host plants and geographic origins, provided additional evidence of the cryptic speciation noted by Inuma et al. (2007) and for the formal recognition of multiple lineages at the species level within B. graminis s. lat. supplemented with morphological examinations of numerous specimensAdvance deposited in various herbaria under ErysiphePublication or Blumeria graminis, a summary of host and geographic ranges, and the re-evaluation of synonyms, ours is the first comprehensive taxonomic treatment of Blumeria complex.
- 46 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
MLSA has been commonly used for classifications in many groups of fungi (Taylor et al.,
2000; Dettman, Jacobson, & Taylor, 2003). Yet, species delimitation of powdery mildew fungi still heavily depends only on rDNA, partly because the primers developed for other house- keeping genes cannot consistently amplify targeted loci (Braun & Cook, 2012). The challenge becomes more severe with historical herbarium samples, in which genomic DNA might have degraded due to long-term storage or inappropriate handling. During our study, besides the primers listed earlier (see Material and Methods), we tested a number of primers for other house- keeping genes, i.e. elongation factor 1 (TEF1) and beta tubulin (TUB2) to amplify DNA from herbarium samples (Inuma et al., 2007; TEF1 primers were newly designed), but the results were discouraging. Even for ITS region, only 29% of samples were successfully sequenced, while
CHS1 had a slightly higher success rate at 38%, possibly because the shorter amplicons (317 bps) were more easily amplified. To explore more potential loci for species delimitation, we investigated the 31 whole genome sequences available in GenBank, specifically the alignment of
93 phylogenetic informative genes (Menardo et al., 2017). Among our newly designed primers, two sets for two loci worked significantly better than others, i.e. 88% for Bgt-4572 and 63% for
Bgt-1929. A BLAST search with the 226 bp amplicon of Bgt-4572 resulted in 81% match with
E3 ubiquitin-protein ligase (XM 032013958) in V. echinocandica. E3 ubiquitin-protein ligase is involved in the control of various cellular processes in eukaryotic cells, including plant immune responses (Marino, Peeters, & Rivas, 2012; Duplan & Rivas, 2014). Recent studies have discovered the presence of E3 ubiquitin ligases in many fungal species and their conserved evolutionAdvance (Marín, 2018). Our data showed that thePublication DNA sequences provided species level resolution albeit a short amplicon (only 226 bp), which can be advantageous for amplifying
DNA from herbarium specimens. Given its common presence in many lineages, we see great
- 47 - Mycoscience: Advance Publication
potential in the application of this gene region for species identification and detection of more fungal groups.
Whether or not cereal powdery mildews have co-evolved with their host plants has been debated in the literature. Some studies demonstrated these fungi might have co-evolved with their hosts (Matsuda & Takamatsu, 2003; Oberhaensli et al., 2011), while other evidence provided no support of this hypothesis (Wyand & Brown, 2003; Inuma et al., 2007). The phylogenetic tree based on concatenated sequences in our study reflected a certain level of co- evolution between Blumeria species and their principal hosts. For instance, the basal location of
B. bulbigera (Fig. 1) and followed by the divergence of B. graminicola with B. bromi-cathartici mirrored the derived phylogenetic position of Triticeae and Poeae in relation to Bromeae
(Soreng et al., 2017). Similarly, the derived position of B. avenae and B. dactylidis, both having
Poeae as principal host, reflected the derived status of Poeae in relation to Triticeae (Fig. 1;
Soreng et al., 2017). It is worth noting that the trees based on individual genes did not resolve deep relationships among species with statistical supports (Supplementary Figs. 1–4). However, besides the principal hosts (see above), almost all species may occur on additional hosts, either of the same or other tribes. A remarkable example is B. graminicola that showed a wide range of hosts including occasional infections on Bromus and Melica (Meliceae), suggesting both host expansion and host jumping may have played roles in increasing host ranges. Collectively, our results suggested it could be the combination of fungus-host co-evolution, host expansion, and host jumping that has shaped the diversity of Blumeria spp. and their host ranges.
In Advancethe light of the phylogenetic relationships Publication among Blumeria spp. and the assumption of co-evolution with their principal hosts, the origins of certain species could be inferred. A possible Eurasian origin of B. bulbigera could be implied because most of the common species
- 48 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
on Bromus are Eurasian (Kellogg, 2015). The wide distribution outside Eurasia can probably be explained by a co-distribution of B. bulbigera along with the wide synanthropic occurrence of several Bromus species as neophytes. For powdery mildews on cereal crops, i.e B. graminis s.str. on wheat (Triticum) and rye (Secale), B. hordei on barley (Hordeum), and B. avenae on oats
(Avena), it was hypothesized previously that the Middle East was the centre of origin, based on investigations of phenotypic and genotypic diversities (Eshed & Wahl, 1970; Troch et al., 2012).
Our analyses of the concatenated data matrix showed B. americana in an ancestral position relative to the cereal powdery mildews (Fig. 1), suggesting the divergence of powdery mildew of cereal crops from B. americana. However, the branch grouping B. avenae, B. dactylidis, B. graminis s. str. and B. hordei has low statistical support, indicating a genetic radiation, i.e., each species diverged independently, which could be a Eurasian origin from the more basal lineages,
B. bulbigera.
The present phylogenetic-taxonomic revision of Blumeria was based on a broad collection of numerous host genera and species from various regions of the world. Nevertheless, these analyses were just a beginning. Host range and distribution of most Blumeria species are still so far only fragmentarily known. The number of previously recorded hosts and countries was very high (Amano, 1986; Braun & Cook, 2012), but in most cases not confirmed through molecular methods. The individual phylogenetic trees suggest the involvement of several additional, as yet unresolved lineages that probably represent additional species. Sequence analyses based on an even wider range of hosts and geographical origins are urgently needed.
Advance Publication
Acknowledgements
- 49 - Mycoscience: Advance Publication
We appreciate the constructive criticisms and suggestions for improvement made by two anonymous reviewers to an earlier version of this manuscript. We thank the Molecular
Technologies Laboratory (MTL), and Electron-Imaging Lab at the Ottawa Research &
Development Centre for technical assistance; herbaria U. S. National Fungus Collections (BPI),
Canadian National Mycological Herbarium (DAOM), Conservatoire et Jardin botaniques de la
Ville de Genève (G), Senckenberg Museum für Naturkunde Görlitz (GLM), Martin-Luther-
Universität, Institut für Biologie, Bereich Geobotanik und Botanischer Garten Herbarium (HAL), and the National Museum of Nature and Science (Tokyo, TNS) for providing specimens. Special thanks to Dr. Lisa A. Castlebury and Shannon Dominick for facilitating the sampling of specimens in BPI by ML, SH, and PS. The study was funded by Agriculture and Agri-Food
Canada STB fungal and bacterial biosystematics J-002272, development of molecular data for
DAOM specimens was supported in part by funding from the Genomics Research and
Development Initiative (GRDI, Project ID 2679) of the Government of Canada.
References
Adhikari, M.K. (2017). Researches on the Nepalese mycoflora 3: Erysiphales from Nepal
Kathmandu, Nepal: Kamala S. Adhikari.
Ahmad, N., Agarwal, D., Bambawal, O., & Puzari, K. (2007). Erysiphaceae of India.
Monographic Treatment. New Delhi: Venus Printers and Publishers.
Amano,Advance K. (1986). Host Range and Geographical Publication Distribution of the Powdery Mildew Fungi.
Tokyo: Japan Scientific Societies Press.
- 50 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
Blumer, S. (1933). Die Erysiphaceen Mitteleuropas mit besonderer Berucksichtigung der
Schweiz. Beiträge zur Kryptogamenflora der Schweiz., 7(1), 483 pp, 167 figs.
Blumer, S. (1967). Echte Mehltaupilze Erysiphaceae: Ein Bestimmungsbuch für die in Europa
vorkommenden Arten: Fischer.
Bonorden, H.F. (1861). Beiträge zur Mykologie. Botanische Zeitung, 19, 193–196.
Braun, U. (1987). A monograph of the Erysiphales (powdery mildews). Beihefte zur Nova
Hedwigia, 89, 1–700.
Braun, U. (1995). The Powdery Mildews (Erysiphales) of Europe. Jena, Germany: VEB Gustav
Fischer Verlag.
Braun, U. (2013). (2210–2232) Proposals to conserve the teleomorph–typified name Blumeria
against the anamorph–typified name Oidium and twenty–two teleomorph–typified
powdery mildew species names against competing anamorph–typified names
(Ascomycota: Erysiphaceae). TAXON, 62(6), 1328–1331. doi:10.12705/626.20
Braun, U., & Cook, R.T. (2012). Taxonomic Manual of the Erysiphales (powdery mildews):
CBS-KNAW Fungal Biodiversity Centre Utrecht, The Netherlands.
Bunkina, I.A. (1967). Novye vidy i formy muchnisto-rosyanykh gribov yuga Dal'nego Vostok.
Novosti sistematiki nizshikh rasteniĭ, 4, 174–177.
Bunkina, I.A. (1973). Novye vidy i formy muchnisto-rosyanykh gribov yuga Primorskogo Kraye
(Dal'niy Vostok). Novosti sistematiki nizshikh rasteniĭ, 10, 79–83. Bunkina,Advance I.A. (1974). Muchnisto-rosyanye griby Publication (sem. Erysiphaceae) yuga dal’nego Vostoka. Komarovskie Chteniya (Vladivostok), 21, 59–90.
Cherewick, W.J. (1944). Studies on the biology of Erysiphe graminis DC. Canadian Journal of
Research, 22c, 52–86.
- 51 - Mycoscience: Advance Publication
Crous, P.W., Phillips, A.J.L., & Baxter, A.P. (2000). Phytopathogenic Fungi from South Africa.
Stellenbosch: University of Stellenbosch Printers/Department of Plant Pathology Press.
Cunnington, J.H., Takamatsu, S., Lawrie, A.C., & Pascoe, I.G. (2003). Molecular identification
of anamorphic powdery mildews (Erysiphales). Australasian Plant Pathology, 32(3),
421–428. doi:10.1071/AP03045
De Candolle, A.P. (1815). Famille de champignons. In A. P. Candolle (Ed.), Flore française
(Vol. 6, pp. 106). Paris, Desray.
Dettman, J.R., Jacobson, D.J., & Taylor, J.W. (2003). A multilocus genealogical approach to
phylogenetic species recognition in the model eukaryote Neurospora. Evolution, 57(12),
2703–2720.
Duplan, V., & Rivas, S. (2014). E3 ubiquitin-ligases and their target proteins during the
regulation of plant innate immunity. Frontiers in Plant Science, 5(42), 1–6.
doi:10.3389/fpls.2014.00042
Ershad, D. (1995). Fungi of Iran. Second Edition. Tehran: Ministry of Agriculture, Agricultural
Research, Education and Extension Organization.
Eshed, N., & Wahl, I. (1970). Host ranges and interrelations of Erysiphe graminis hordei, E.
graminis tritici and E. graminis avenae. Phytopathology, 60(4), 628–634.
Everts, K.L., Leath, S., & Finney, P.L. (2001). Impact of powdery mildew and leaf rust on
milling and baking quality of soft red winter wheat. Plant Disease, 85(4), 423–429.
doi:10.1094/pdis.2001.85.4.423doi:10.1094/Phyto-60-628
Golovin,Advance P.N. (1958). Obsor radov semejstva Erysiphaceae.Publication Sborn. Rabot. Inst. Priel. Zool.
Phytopathol. Leningrad, 5, 101–139.
- 52 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
Inuma, T., Khodaparast, S.A., & Takamatsu, S. (2007). Multilocus phylogenetic analyses within
Blumeria graminis, a powdery mildew fungus of cereals. Molecular Phylogenetics and
Evolution, 44(2), 741–751. doi: 10.1016/j.ympev.2007.01.007.
Jaczewski, A.A. (1927). Karmanny opredelitel' gribov. Vyp. 2. Muchnistorosyanye griby:
Mikologicheskaya Laboratoriya Imeni Professora A.A. Jaczewskogo, Gosudarstvennogo
Instituta Opytnoy Agronomii, Leningrad.
Katoh, K., Rozewicki, J., & Yamada, K.D. (2017). MAFFT online service: multiple sequence
alignment, interactive sequence choice and visualization. Brief Bioinformatics, bbx108-
bbx108. doi:10.1093/bib/bbx108
Kellogg, E.A. (2015). Flowering plants. Monocots: Poaceae (Vol. 13). Cham, Germany:
Springer.
Kornerup, A., & Wanscher, J.H. 1978. Methuen handbook of colour. London: Eyre Methuen.
Link, H.F. (1809). Observationes in ordines plantarum naturales. Dissertatio I. Magazin der
Gesellschaft Naturforschenden Freunde Berlin, 3(1), 3–24.
Link, H.F. (1824). Caroli a Linné Species plantarum: exhibentes plantas rite cognitas, ad genera
relatas, cum differentiis specificis, nominibus trivialibus, synonymis selectis, locis
natalibus, secundum systema sexuale digestas (Ed. 4., post Reichardianam quinta ed.
Vol. v.6:pt.1–2). Berolini :: Impensis G.C. Nauk.
Mains, E.B. (1933). Host specialization of Erysiphe graminis Tritici. Proceedings of the
National Academy of Sciences of the United States of America, 19(1), 49–53.
doi:10.1073/pnas.19.1.49Advance. Publication
Mains, E.B., & Diktz, S. (1930). Physiologic forms of Barley mildew, Erysiphe graminis hordei.
Phytopathology, 20(3), 229–239.
- 53 - Mycoscience: Advance Publication
Marchal, E. (1902). De la specialisation du paristisme chez l’Erysiphe graminis. Comptes rendus
hebdomadaires des séances de l'Académie des sciences, 135, 210–212.
Marín, I. (2018). Origin and evolution of fungal HECT ubiquitin ligases. Scientific Reports, 8(1),
6419. doi:10.1038/s41598-018-24914-x
Marino, D., Peeters, N., & Rivas, S. (2012). Ubiquitination during Plant Immune Signaling.
Plant Physiology, 160(1), 15–27. doi:10.1104/pp.112.199281
Matsuda, S., & Takamatsu, S. (2003). Evolution of host–parasite relationships of Golovinomyces
(Ascomycete: Erysiphaceae) inferred from nuclear rDNA sequences. Molecular
Phylogenetics and Evolution, 27(2), 314–327. doi:https://doi.org/10.1016/S1055-
7903(02)00401-3
Menardo, F., Wicker, T., & Keller, B. (2017). Reconstructing the Evolutionary History of
Powdery Mildew Lineages (Blumeria graminis) at Different Evolutionary Time Scales
with NGS Data. Genome Biology and Evolution, 9(2), 446–456. doi:10.1093/gbe/evx008.
Mendes, M.A.S., Silva, V.L.d., Dianese, J.C., Ferreira, M.A.S.V., Santos, C.E.N.d., Neto,
E.G., . . . Castro, C. (1998). Fungos em plantas do Brasil. Brasília: Embrapa Produção de
Informção / Embrapa Recursos Genéticos e Biotecnologia.
Mori, Y., Sato, Y., & Takamatsu, S. (2000). Evolutionary analysis of the powdery mildew fungi
using nucleotide sequences of the nuclear ribosomal DNA. Mycologia, 92(1), 74–93.
doi:10.2307/3761452.
Nylander, J.A.A. (2004). MrModeltest v2: Evolutionary Biology Centre, Uppsala University.
RetrievedAdvance from https://github.com/nylander/MrModeltest2 Publication.
Oberhaensli, S., Parlange, F., Buchmann, J.P., Jenny, F.H., Abbott, J.C., Burgis, T.A., Wicker, T.
(2011). Comparative sequence analysis of wheat and barley powdery mildew fungi
- 54 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
reveals gene colinearity, dates divergence and indicates host-pathogen co-evolution.
Fungal Genetics and Biology, 48(3), 327–334.
Oku, T., Yamashita, S., Doi, Y., & Nishihara, N. (1985). Host range and forma specialis of
cocksfoot powdery mildew fungus (Erysiphe graminis DC.) found in Japan. Japanese
Journal of Phytopathology, 51(5), 613–615. doi:10.3186/jjphytopath.51.613.
Ronquist, F., Teslenko, M., van der Mark, P., Ayres, D.L., Darling, A., Höhna, S., . . .
Huelsenbeck, J.P. (2012). MrBayes 3.2: Efficient bayesian phylogenetic inference and
model choice across a large model space. Systematic Biology, 61(3), 539–542.
doi:10.1093/sysbio/sys029.
Saccardo, P.A. (1886). Sylloge fungorum omnium hususque cognitorum (Vol. IV). Padua.
Salmon, E.S. (1900). A monograph of the Erysiphaceae (Vol. 9): Torrey Botanical Club.
Seko, Y., Heluta, V., Grigaliunaite, B., & Takamatsu, S. (2011). Morphological and molecular
characterization of two ITS groups of Erysiphe (Erysiphales) occurring on Syringa and
Ligustrum (Oleaceae). Mycoscience, 52(3), 174–182. doi:10.1007/S10267-010-0088-X.
Sharma, N.D., & Khare, C.P. (1995). A Check-list and Selected Bibliography of Powdery Mildew
Fungi of India. Jabalpur: Jawaharlal Nehru Agricultural University.
Shin, H.D. (2000). Erysiphaceae in Korea. Suwon: National Institute of Agricultural Science and
Technology.
Shin, H.D., & La, Y.J. (1993). Morphology of edge lines of chained immature conidia on
conidiophores in powdery mildew fungi and their taxonomic significance. Mycotaxon, 46Advance, 445–451. Publication Soreng, R.J., Peterson, P.M., Romaschenko, K., Davidse, G., Teisher, J.K., Clark, L.G., . . .
Zuloaga, F.O. (2017). A worldwide phylogenetic classification of the Poaceae
- 55 - Mycoscience: Advance Publication
(Gramineae) II: An update and a comparison of two 2015 classifications. 55(4), 259–290.
doi:10.1111/jse.12262.
Speer, E.O. (1975 [1973–1974]). Untersuchungen zur Morphologie und Systematik der
Erysiphaceen I. Die Gattung Blumeria Golovin un ihre typusart Erysiphe graminis DC.
Sydowia, 27, 1–6.
Sumstine, D.R. (1913). Studies in North American Hyphomycetes—II: The Tribe Oosporeae.
Mycologia, 5(2), 45–61.
Swofford, D.L. (2002). PAUP*. Phylogenetic analysis using parsimony (*and other methods).
version 4.0 b10 (computer program). In. Sunderland, Massachusetts: Sinauer Associates.
Taylor, J.W., Jacobson, D.J., Kroken, S., Kasuga, T., Geiser, D.M., Hibbett, D.S., & Fisher,
M.C. (2000). Phylogenetic species recognition and species concepts in fungi. Fungal
Genetics and Biology, 31, 21–32.
Troch, V., Audenaert, K., Bekaert, B., Höfte, M., & Haesaert, G. (2012). Phylogeography and
virulence structure of the powdery mildew population on its 'new' host triticale. BMC
Evolutionary Biology, 12(1), 76. doi:10.1186/1471-2148-12-76
Turland, N.J., Wiersema, J.H., Barrie, F.R., Greuter, W., Hawksworth, D.L., Herendeen, P.S.,
Knapp, S., Kusber, W.-H., Li, D.-Z., Marhold, K., May, T.W., McNeill, J., Monro, A.M.,
Prado, J., Price, M.J., Smith, G.F. (eds.) 2018. International Code of Nomenclature for
algae, fungi, and plants (Shenzhen Code) adopted by the Nineteenth International
Botanical Congress Shenzhen, China, July 2017. Regnum Vegetabile 159. Glashütten:
KoeltzAdvance Botanical Books. Publication
- 56 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
Voytyuk, S.O., Heluta, V.P., Wasser, S.P., Nevo, E., & Takamatsu, S. (2009). Biodiversity of the
Powdery Mildew Fungi (Erysiphales, Ascomycota) of Israel. Ruggell: A.R.A. Gantner
Verlag.
White, T.J., Bruns, T., Lee, S., & Taylor, J. (1990). Amplification and direct sequencing of
fungal ribosomal RNA genes for phylogenies. In M. A. Innis, D. H. Gelfand, J. J.
Sninsky, & T. J. White (Eds.), PCR protocols: A guide to methods and applications (pp.
315–322). San Diego: Academic Press.
Wyand, R.A., & Brown, J.K.M. (2003). Genetic and forma specialis diversity in Blumeria
graminis of cereals and its implications for host-pathogen co-evolution. Molecular Plant
Pathology, 4(3), 187–198. doi:10.1046/j.1364-3703.2003.00167.
Advance Publication
- 57 - Mycoscience: Advance Publication
Figure legends
Advance Publication
- 58 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
Fig. 1 – Phylogeny of Blumeria graminis s.lat. inferred from concatenated sequences of rDNA-
ITS, CHS1, and two hypothetic protein loci (Bgt-1929, Bgt-4572). Taxon labels include voucher numbers, host name, and country codes (CAN Canada, CZE Czech Republic, UK England, FIN
Finland, DEU Germany, ISR Israel, JPN Japan, MEX Mexico, RUS Russia, UKR Ukraine, USA
United States); superscript EET stands for ex-epitype, EHT ex-holotype, ENT ex-neotype; values on branches are parsimony bootstrapping value (bp)/Bayesian posterior probability (pp), ~ indicates either bp <70 or pp <0.9. Sequences of taxa in grey font were downloaded from
GenBank. Tribes (and subtribes for B. avenae and B. dactylidis) of principal hosts were noted under the species names in parentheses.
Advance Publication
- 59 - Mycoscience: Advance Publication
Fig. 2 – Blumeria graminis s.str. A: Infected leaf surface with primary mycelia and conidiophores (DAOM 225780, asexual stage on the left), and secondary mycelia and chasmothecia (DAOM 74558, sexual stage on the right); B: Close-up of chasmothecia and secondary mycelia (DAOM 74558); C: A branched secondary hypha with basal septa (arrows,
DAOM 74558); D: Conidiophore singly arising from mother cell (DAOM 225780, DAOM
161299); E: Asci ellipsoid or ovoid, with or without stalk (DAOM 74558); F: Conidia, arrow shows germ tube (DAOM 225780); G: Hyphal appressoria (DAOM 225780, DAOM 161299);
H: A secondary hypha unbranched, with one septum at base (arrow, DAOM 74558); I: SEM of conidiumAdvance apical wall thickened (on the left, DAOM Publication 225780) and un-thickened (on the right, DAOM 161299). Bars: A 0.5 mm; B 100 μm; C–H 20 μm; I 2 μm.
- 60 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
Fig. 3 – Blumeria americana sp. nov. A: Infected leaf adaxial (left) and abaxial surfaces (DAOM
156886) showing asexual stage; B:Infected leaf with sexual stage (DAOM 145059); C: Close-up of chasmothecia imbedded in secondary hyphae (DAOM 145059); D: Asci clavate, ellipsoid, ovoid with sinuous or branched stalk (DAOM 137541); E: Aseptate secondary hyphae with narrow lumen; F: Young conidiophores arising from mother cells singly (top, DAOM 217856,
DAOM 156886) or in pairs (bottom, DAOM 156886); G: Branched foot-cells (DAOM 186037);
H: Mature conidiophores and conidia (DAOM 217856); I: Hyphal appressoria of various shapes; J: SEM Advanceview of conidia with scale-like artifacts onPublication the surface and a thickened patch at apex (DAOM 217856). Bars: A, B 1 mm; C 100 μm; D 50 μm; E–I 20 μm; J 5 μm (including inset).
- 61 - Mycoscience: Advance Publication
Fig. 4 –Blumeria avenae sp. nov. A: Various stages of infection on the leaf surface with light orange to brownish mycelia (DAOM 236220, 147852); B: Close-up of conidiophores on leaf surface (DAOM 236220); C: Conidia, note two with germ tubes at or near apices (DAOM
236220, 147852, arrows); D: Appressoria nipple-shaped (DAOM 236220, 147852), single or in opposite pairs; E–F: Single conidiophore arising from mother cell, the septum between mother cell and foot cell elevated severely (E, DAOM 236220, arrow) or slightly (F, DAOM 147852);
G: Two conidiophores arising from mother cell in pairs (DAOM 236220); H: A cluster of conidiophores arising from irregular shaped mother cells (DAOM 236220); I: SEM close up apical wall of conidia. Bars: A 0.5 mm; B 100 μm; C–H 20 μm; I 2 µm.
Advance Publication
- 62 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
Fig. 5 – Blumeria bromi-cathartici sp. nov. (TNS-F87248 = MUMH 0117). A: Infection on leaf surface showing light yellow to orange primary mycelia and conidiophores; B: Close-up of conidiophores on leaf surface; C: Hypha branching at a narrow angle, and hyphal appressoria nipple-shaped and single; D–E: Conidiophores at different developing stages singly arising from mother cell; F: Primary conidia mostly oblong; G: Blumeria-type germination of a conidium; H:
SEM view of apical walls. Bars: A 0.5 mm; B 100 μm; C–G 20 μm; H 2 µm.
Advance Publication
- 63 - Mycoscience: Advance Publication
Fig. 6 – Blumeria bulbigera comb. nov. A: Infection on adaxial leaf surface showing yellow primary mycelia and conidiophores (DAOM 82541); B: White secondary mycelia and chasmothecia produced on adaxial leaf surface (GLM-F54349); C: Exposed disk-shaped chasmothecia with deep depression on upper surfaces (GLM-F54349); D: Asci with cylindrical stalk (GLM-F54349); E: Conidiophore arising singly from irregular mother cell (DAOM 82541);
F: Nipple-shaped appressoria arising singly or in opposite pairs, ovoid swelling at the end or middle of hyphae (see arrows, DAOM 82541, GLM-F62360); G: Conidia of subglobose, ovoid, oblong, and lime-shaped, germ tubes produced near the apices (DAOM 82541, GLM-F62360); H: SecondaryAdvance hypha with several septa (see arrows, Publication GLM-F54349), I: SEM view of conidia; J: Apical wall of conidia (DAOM 82541). Bars: A–C 100 μm; D–H 20 μm; I 5 μm; J 2 µm.
- 64 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
Fig. 7 – Blumeria dactylidis sp. nov. A: Infection on adaxial leaf surface showing brown primary mycelia and conidia production (left, DAOM 91654), and on abaxial leaf surface showing greyish white secondary mycelia and chasmothecia (right, GLM-F50119); B: Close-up of conidia chains (DAOM 118220); C: Chasmothecium side view (upper) and overview (lower) showing the deep depression at the upper surface and the surrounding white secondary mycelia
(GLM-F79570); D: Secondary hyphae aseptate and unbranched (GLM-F50119); E: Appressoria in nipple and lobe shapes (DAOM 91654, 118220); F–H showing one conidiophore per mother cell (DAOM 91654): F: Conidiophore with elevated septum between mother cell and foot cell, G: YoungAdvance foot cell, H: Conidiophore with slightly Publication elevated septum between mother cell and foot cell; I: Conidia, producing one or two germ tubes (DAOM 91654, DAOM 118220, arrows); J:
Asci with slightly protruding stalk (GLM-F79570); K: SEM view of apical wall of conidia un- thickened. Bars: A 0.5 mm; B, C 100 μm; D–J 20 μm; K 2 μm.
- 65 - Mycoscience: Advance Publication
Fig. 8 – Blumeria graminicola sp. nov. A: Chasmothecia covered with white secondary hyphae on infected leaf surface (DAOM 179493); B: Primary hyphae and conidia (arrow) co-exist with secondary hyphae and chasmothecium (DAOM 159510); C: Filiform appendages of chasmothecium with a septum at the base or near base (arrows, DAOM 159510); D: Asci subglobose, or ovoid with an unbranched short stalk (DAOM 159510); E: Secondary hyphae with septa (arrow, DAOM 179493); F: Single conidiophore arising from one mother cell
(DAOM 159510); G: Hyphal appressoria (DAOM 181460, DAOM 91194); H: Two conidiophores arising from one mother cell, and branched foot-cell (arrows, DAOM 179493, DAOM Advance159510); I: Conidia, note one conidium Publicationproducing a germ-tube; J: SEM view of scale- like artifacts on surface of conidia, thickened apical wall with depressed center (DAOM 24040);
K: Close-up of apical wall of conidia (DAOM 91194). Bars: A 0.5 mm; B 100 μm; C–I 20 μm; J
5 μm; K 1 μm.
- 66 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
Fig. 9 – Blumeria hordei sp. nov. (A–F DAOM 18154, G–I GLM-F99595 and DAOM 18154).
A: Chasmothecia embedded in greyish to brownish secondary mycelia, developed simultaneously with deeper colored primary mycelia and conidia (arrow, DAOM 18154); B:
Close-up of brownish conidial chains; C: Clavate or ovoid asci with wiggly stalks; D: Two conidiophores arising from single mother cell; E: Conidiophores arising singly from mother cells; F: Secondary hyphae arising from primary hyphae with one septum at the base; G:
Conidia, mostly with round ends compared with pointed ends (i.e. B. graminicola Fig. 8 I); H: Nipple shapedAdvance appressoria mostly in pairs; I: SEM Publication close-up of apical wall of conidia. Bars: A 0.5 mm; B 100 μm; C–H 20 μm; I 5 µm.
- 67 - Mycoscience: Advance Publication
Declaration of conflict interests: none
Declaration of contributions: All authors have participated in the research and article preparation, and agreed on publishing present work. The project was conceived and designed by
ML, SH, UB; and PS, KRB, SH, SK, ML developed molecular data; UB, SK, ML performed morphological examinations and taxonomy; UB handled nomenclature; KH scanning electron- microscopy; ML and UB drafted manuscript, others contributed to editing.
Advance Publication
- 68 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
Table 1. Fungal specimens for multi-locus sequence analyses ID Vouchera Hostb Country, province Year ITS CHS1 Bgt1929 Bgt4572 Blumeria americana HAL 000028F Apera spica-venti DEU, Sachsen-Anhalt 1981 n.a. n.a. MT633883 n.a.
DAOM 96986 Elymus canadensis USA, Wisconsin 1963 MT622285 n.a. MT633813 MT650031 BPI 562942 Elymus canadensis USA, Wisconsin 1963 MT622266 n.a. MT633895 MT649952 BPI 562946 Elymus canadensis USA, Washington 1934 n.a. n.a. n.a. MT649953
BPI 563259 Elymus elymoides (Sitanion hystrix) USA, Arizona 1945 n.a. n.a. MT633897 MT650005
BPI 563260 Elymus elymoides (Sitanion hystrix) USA, California 1939 n.a. n.a. MT633850 MT650006
BPI 562963 Elymus glaucus USA, Washington 1938 MT622267 n.a. MT633860 MT649955
DAOM 155345 Elymus lanceolatus (Agropyron dasystachyum) CAN, Northwest 1940 n.a. n.a. n.a. MT650044 Territories DAOM 137541 Elymus lanceolatus (Agropyron dasystachyum) USA, Wyoming 1961 MT622287 n.a. MT633811 MT650033
BPI 562806 Elymus lanceolatus (Agropyron dasystachyum) USA, Wyoming 1961 n.a. n.a. MT633896 MT649926
BPI 562805 Elymus lanceolatus (Agropyron dasystachyum) USA, Oregon 1935 n.a. n.a. MT633862 MT649925
DAOM Elymus repens (Agropyron repens) CAN, Alberta 1980 MT622296 n.a. MT633817 MT650055 186037HT BPI 562811 Elymus violaceus (Agropyron latiglume) USA, Alaska 1948 n.a. n.a. n.a. MT649927
BPI 562998 Hordeum brachyantherum USA, Alaska 1948 n.a. n.a. n.a. MT649965
DAOM 217858 Hordeum jubatum CAN, Saskatchewan 1931 n.a. n.a. MT633831 MT650057
DAOM 156886 Hordeum jugatum CAN, Manitoba 1935 n.a. n.a. n.a. MT650046
DAOM 155342 Hordeum jugatum CAN, Northwest 1940 MT622292 n.a. MT633821 n.a. Territories DAOM 145059 Leymus cinereus (Elymus cinereus) CAN, British Columbia 1953 n.a. n.a. n.a. MT650034
BPI 562828 Pascopyrum smithii (Agropyron smithii) USA, North Dakota 1942 n.a. n.a. n.a. MT649930
DAOM 217856 Psathyrostachys juncea (Elymus junceus) CAN, Saskatchewan n.a. MT622297 n.a. n.a. n.a.
BPI 562967 Psathyrostachys juncea (Elymus junceus) USA, North Dakota 1942 MT622268 n.a. MT633905 MT649957 B. avenae DAOM 147852 Avena barbata CAN, Ontario 1965 MT622288 n.a. MT633886 MT650036 BPI 562860 Avena fatua USA, California 1942 n.a. n.a. n.a. MT649935
DAOM Avena sativa GBR, Exeter 1948 MT622301 n.a. MT633815 MT650063 236220HT BPI 562866 Avena sativa GBR, Exeter 1948 n.a. n.a. n.a. MT649936
BPI 562873 Avena sterilis ISR, Jerusalem 1951 n.a. MT633953 MT633846 MT649937 B. bulbigera DAOM 82541ET Bromus hordeaceus subsp. hordeaceus (Bromus FIN, Regio aboënsis 1957 MT622280 n.a. n.a. n.a. mollis) B. dactylidis DAOM 91654 Anthoxanthum odoratum FIN, Regio aboënsis 1961 MT622284 MT633920 MT633814 MT650030 HAL 000018F Anthoxanthum odoratum DEU, Sachsen-Anhalt 1978 n.a. n.a. MT633885 n.a.
BPI 562894 Bromus catharticusAdvance USA, GeorgiaPublication 1938 n.a. n.a. n.a. MT649939
- 69 - Mycoscience: Advance Publication
HAL 000027F Bromus ramosus subsp. benekenii (Bromus DEU, Sachsen-Anhalt 1977 MT622307 n.a. MT633805 n.a. benekenii) DAOM Dactylis glomerata CAN, British Columbia 1934 MT622286 MT633919 MT633812 MT650032 118220HT HAL 000029F Dactylis glomerata DEU, Sachsen-Anhalt 1978 MT622308 n.a. MT633903 n.a.
BPI 562935 Dactylis glomerata DEU, Oberbayern 1950 n.a. MT633935 MT633861 MT649950 BPI 562975 Festuca pratensis CZE, Kromeriz 1962 n.a. MT633946 MT633859 MT649959 HAL 000025F Festuca gigantea DEU, Sachsen-Anhalt 1977 n.a. MT633944 MT633806 MT650066 BPI 563038 Hordeum vulgare ETH, Jimma 1954 n.a. n.a. n.a. MT649973
BPI 563046 Hordeum vulgare JPN, Kyoto 1895 n.a. n.a. n.a. MT649975
HAL 000006F Phleum phleoides RUS, Baskortostan 1977 n.a. n.a. MT633809 n.a.
BPI 563065 Phleum pratense LVA, Vidzeme 1935 n.a. n.a. n.a. MT649979 B. graminicola DAOM 150568 Agrostis sp. CAN, Manitoba 1925 MT622290 MT633915 n.a. MT650040
HAL 000022F Alopecurus geniculatus DEU, Sachsen-Anhalt 1980 n.a. MT633967 MT633884 n.a.
DAOM 4071 Anthoxanthus nitens (Hierochloe odorata) CAN, Saskatchewan 1936 MT622275 MT633955 MT633826 MT650016
HAL 000016F Apera spica-venti DEU, Sachsen-Anhalt 1975 MT622305 MT633961 MT633882 n.a. BPI 562847 Apera spica-venti (Agrostis spica-venti) LVA, Vidzeme 1931 n.a. n.a. MT633843 MT649933
DAOM 152932 Beckmannia eruciformis CAN, Saskatchewan 1926 MT622291 n.a. n.a. MT650043
DAOM 217878 Beckmannia syzigachne CAN, Saskatchewan 1959 MT622298 MT633911 n.a. MT650059
BPI 562902 Bromus japonicus CHN, Nanking 1931 n.a. n.a. n.a. MT649943
BPI 562917 Bromus catharticus var. elatus (Bromus unioloides) USA, Texas 1932 n.a. n.a. n.a. MT649948
BPI 562911 Bromus diandrus var. rigidus (Bromus rigidus) USA, Washington 1935 n.a. MT633962 MT633844 MT649945
BPI 562916 Bromus tectorum USA, Washington 1935 n.a. MT633936 MT633842 MT649947 BPI 562924 Dactylis glomerata ROU, Lapusna-Cornesti 1934 n.a. n.a. n.a. MT649949
DAOM 155348 Elymus lanceolatus (Agropyron dasystachyum) CAN, Northwest Territories 1940 n.a. n.a. n.a. MT650045
BPI 562974 Festuca gigantea DEU, Mitterfranken 1946 n.a. MT633934 MT633899 MT649958 BPI 562965 Festuca idahoensis USA, Washington 1935 n.a. MT633960 MT633901 MT649956 BPI 562984 Holcus lanatus DEU, Mittelfranken 1946 n.a. n.a. n.a. MT649961
DAOM 165199 Melica sp. USA, California 1975 n.a. n.a. MT633872 MT650051
DAOM 55075 Melica subulata CAN, British Columbia 1956 n.a. MT633939 MT633835 MT650021 DAOM 179493 Milium effusum FIN, Perä-Pohjanmaa 1979 MT622295 MT633950 MT633818 MT650053
BPI 563056 Milium effusum DEU, Mittelfranken 1947 n.a. n.a. n.a. MT649978
BPI 562826 n.a. (Agropyron sericeum) USA, Alaska 1948 n.a. n.a. n.a. MT649929
DAOM 89817 Poa annua CAN, Quebec 1959 n.a. n.a. n.a. MT650026
DAOM 231497 Poa arctica CAN, Northwest 1967 MT622300 MT633909 MT633830 MT650062 Territories DAOM 91194 Poa arctica CAN, Nunavut 1962 MT622283 MT633921 MT633823 MT650029
BPI 563089 Poa arida USA, North Dakota 1941 n.a. n.a. n.a. MT649981
BPI 563094 Poa bulbosa RUS, Turkmenskaya 1978 n.a. MT633932 MT633898 MT649982 DAOM 217863 Poa compressaAdvance CAN, SaskatchewanPublication 1927 n.a. n.a. MT633870 MT650058
- 70 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
DAOM 152605 Poa compressa CAN, Manitoba 1933 n.a. MT633965 MT633874 MT650042 BPI 563101 Poa compressa USA, Kansas 1953 n.a. MT633940 n.a. MT649985
DAOM 207718 Poa crocata CAN, Manitoba 1926 n.a. n.a. MT633871 MT650056
DAOM 38753 Poa glauca CAN, Quebec 1948 n.a. n.a. n.a. MT650019
DAOM 148500 Poa glauca CAN, Ontario 1973 n.a. n.a. MT633876 MT650039
BPI 563103 Poa glaucifolia USA, North Dakota 1941 n.a. MT633931 MT633892 MT649986
BPI 563108 Poa nemoralis DEU, Oberpfalz 1946 MT622270 MT633945 MT633841 MT649987
DAOM 148498 Poa nemoralis var. montana CAN, Ontario 1973 n.a. MT633917 MT633834 MT650038
DAOM 181460 Poa palustris CAN, Manitoba 1979 n.a. MT633912 MT633832 MT650054 DAOM 89819 Poa palustris CAN, Quebec 1959 n.a. n.a. MT633877 n.a.
DAOM 149529 Poa palustris CAN, Ontario 1971 n.a. MT633916 n.a. n.a.
BPI 563115 Poa palustris USA, Wisconsin 1948 n.a. n.a. n.a. MT649988
DAOM 145060 Poa pratensis CAN, Northwest Territories 1955 n.a. n.a. n.a. MT650035
DAOM Poa pratensis CAN, Ontario 1974 n.a. MT633954 MT633820 MT650048 159510HT DAOM 90074 Poa pratensis USA, Wisconsin 1962 n.a. MT633966 MT633887 MT650027 BPI 563132 Poa pratensis USA, Alaska 1951 MT622271 MT633948 MT633891 MT649989 BPI 563135 Poa pratensis USA, Virginia 1940 n.a. n.a. n.a. MT649990
BPI 563138 Poa pratensis USA, Wisconsin 1962 MT622272 MT633949 MT633890 MT649991
BPI 563148 Poa pratensis USA, Alaska 1951 n.a. MT633947 MT633865 MT649992
BPI 563158 Poa pratensis USA, Oregon 1937 n.a. MT633930 MT633900 MT649993 BPI 563162 Poa pratensis USA, California 1946 n.a. MT633964 MT633889 MT649994 DAOM 159686 Poa pratensis subsp. alpigena CAN, Northwest 1974 n.a. MT633938 MT633810 MT650049 Territories BPI 563191 Poa secunda USA, Washington 1935 n.a. n.a. n.a. MT649996
BPI 563096 Poa secunda (Poa canbyi) USA, North Dakota 1941 n.a. n.a. n.a. MT649983
BPI 563098 Poa secunda (Poa canbyi) USA, Washington 1935 n.a. n.a. n.a. MT649984
BPI 563183 Poa secunda (Poa scabrella) USA, Oregon 1935 n.a. n.a. n.a. MT649995
BPI 563076 Poa sp. IND, Srinagar 1960 n.a. n.a. n.a. MT649980
HAL 000019F Poa trivialis DEU, Sachsen-Anhalt 1977 MT622306 n.a. MT633867 n.a.
BPI 563200 Poa trivialis NLD, Warmond 1958 MT622273 MT633929 MT633840 MT649997
BPI 563205 Poa vaseyochloa USA, Oregon 1938 n.a. n.a. n.a. MT649998 BPI 563212 Polypogon monspeliensis USA, California 1945 n.a. MT633928 MT633839 MT649999
BPI 563216 Polypogon monspeliensis USA, Washington 1935 n.a. MT633959 MT633838 MT650000 DAOM 91193 Puccinellia angusta CAN, Nunavut 1962 MT622282 n.a. MT633824 MT650028
BPI 563219 Puccinellia angusta CAN, Northwest Territories 1962 n.a. n.a. MT633888 MT650001
BPI 563220 Puccinellia borealis USA, Alaska 1948 n.a. n.a. n.a. MT650002
BPI 562833 Thinopyrum intermedium (Agropyron trichophorum) USA, North Dakota 1942 n.a. n.a. n.a. MT649932
BPI 563289 Triticum aestivum AUS, New South Wales 1964 n.a. n.a. n.a. MT650011 B. graminis s.str. Advance Publication
- 71 - Mycoscience: Advance Publication
HAL 000007F Brachypodium sylvaticum RUS, Bashkortostan 1977 MT622302 n.a. MT633868 n.a.
BPI 562937 Dasypyrum villosum ROU, Dolj 1979 n.a. MT633957 MT633902 MT649951
DAOM 984745 Elymus cf trachycaulus CAN, New Brunswick 2016 MT622310 MT633937 MT633829 n.a.
BPI 562803 Elymus ciliaris (Agropyron ciliare) CHN, Nanking 1931 n.a. n.a. MT633863 MT649924
DAOM 148234 Elymus hystri (Hystrix patula) CAN, Quebec 1955 MT622289 MT633918 MT633822 MT650037 DAOM 161299 Elymus hystri (Hystrix patula) CAN, Ontario 1977 MT622293 MT633914 MT633819 MT650050
HAL 000009F Elymus repens UKR, Zaporizhia 1984 MT622303 n.a. MT633808 MT650064
DAOM 156887 Elymus repens (Agropyron repens) CAN, Manitoba 1934 n.a. n.a. MT633873 MT650047
DAOM 152080 Elymus repens (Agropyron repens) CAN, Manitoba 1945 n.a. n.a. MT633875 MT650041
DAOM 217883 Elymus repens (Agropyron repens) CAN, Saskatchewan 1939 n.a. n.a. MT633869 MT650060
DAOM 40453 Elymus repens (Agropyron repens) CAN, Prince Edward 1953 MT622278 MT633924 MT633802 MT650020 Island DAOM 225780 Elymus repens (Agropyron repens) CAN, British Columbia 1998 MT622299 MT633910 MT633816 MT650061
DAOM 27352 Elymus repens (Agropyron repens) CAN, Quebec 1951 MT622277 MT633968 MT633880 n.a. DAOM 82544 Elymus repens (Agropyron repens) FIN, Ostrobotnia 1951 n.a. n.a. MT633878 MT650025
DAOM 82543 Elymus repens (Agropyron repens) FIN, Lapp. Enontekiensis 1960 n.a. MT633956 MT633879 MT650024
BPI 562819 Elymus repens (Agropyron repens) ROU, Muntenia 1933 n.a. n.a. n.a. MT649928
DAOM 74558 Elymus repens (Agropyron repens) USA, Wisconsin 1960 MT622279 MT633923 n.a. MT650022 BPI 562802 Elymus_caninus (Agropyron caninum) DEU, Mittelfranken 1947 n.a. n.a. n.a. MT649923
BPI 562989 Hordeum sp. DEU, Bergisches Land 1931 n.a. n.a. n.a. MT649963
BPI 563055 Milium effusum DEU, Thueringen 1945 MT622269 MT633933 MT633853 MT649977 DAOM 169330 Phleum pratense CAN, New Brunswick 1978 MT622294 MT633913 MT633833 MT650052
DAOM 38670 Secale cereale CAN, Nova Scotia 1952 n.a. MT633952 MT633836 n.a.
BPI 563247 Secale cereale DEU, Mittelfranken 1947 n.a. MT633927 MT633851 MT650004
HAL 000026F Secale cereale DEU, Sachsen-Anhalt 1977 n.a. n.a. MT633866 n.a.
BPI 563245 Secale cereale USA, Wisconsin 1957 n.a. MT633958 MT633852 MT650003 BPI 563290 Triticum aestivum AUS, New South Wales 1969 n.a. n.a. n.a. MT650012
DAOM 984746 Triticum aestivum CAN, Ontario 2016 MT622311 MT633951 MT633803 MT650067 DAOM 984747 Triticum aestivum CAN, Ontario 2016 MT622312 MT633908 MT633828 MT650068
DAOM 984748 Triticum aestivum CAN, Ontario 2016 MT622313 n.a. MT633827 MT650069
DAOM 7738 Triticum aestivum CAN, Nova Scotia 1936 n.a. MT633925 MT633837 MT650017
HAL 000036F Triticum aestivum CHN, Xinjian Uyg. Aut. Reg 1959 MT622309 n.a. MT633804 n.a.
BPI 563287 Triticum aestivum CHN, Nanking 1932 n.a. n.a. n.a. MT650010
BPI 553981 Triticum aestivum (Triticum vulgare) CHN, Kwangsi 1938 n.a. n.a. MT633864 MT649922
BPI 563264 Triticum sp. DEU, n.a. 1974 n.a. MT633963 MT633848 MT650008
BPI 563263 Triticum sp. IND, Hebbal 1968 n.a. n.a. MT633849 MT650007 B. hordei BPI 859594 Agrostis exarata USA, California 1939 n.a. n.a. n.a. MT650013
BPI 562851 AlopecurusAdvance aequalis DEU, BavariaPublication 1946 n.a. n.a. n.a. MT649934
- 72 - Taxonomic revision of Blumeria based on multi-gene DNA sequences, host preferences and morphology
BPI 562908 Bromus hordeaceus subsp. hordeaceus (Bromus IRL, Boyne Valley 1933 n.a. n.a. n.a. MT649944 mollis) BPI 562915 Bromus tectorum USA, Nebraska 1941 n.a. n.a. n.a. MT649946
BPI 562987 Hordeum sp. CHN, Chekiang 1931 n.a. n.a. n.a. MT649962
BPI 562996 Hordeum sp. EGY, Gizo 1978 n.a. n.a. MT633858 MT649964
BPI 563004 Hordeum murinum ISR, Jerusalem 1935 n.a. MT633943 MT633857 MT649966 HAL 000010F Hordeum murinum UKR, Zaporizhia 1984 MT622304 MT633942 MT633807 MT650065 BPI 563022 Hordeum vulgare AUS, New South Wales 1977 n.a. n.a. MT633855 MT649969
BPI 563021 Hordeum vulgare AUS, Narrabri 1966 n.a. n.a. MT633894 MT649968
DAOM 18154HT Hordeum vulgare CAN, Quebec 1940 MT622276 n.a. MT633825 MT650018
BPI 563037 Hordeum vulgare IND, Panakpur 1956 n.a. n.a. n.a. MT649972
BPI 563033 Hordeum vulgare IND, Katgodam 1948 n.a. n.a. MT633854 MT649970
BPI 563039 Hordeum vulgare MEX, Mixquiahuala 1947 n.a. n.a. MT633893 MT649974
BPI 563035 Hordeum vulgare USA, Texas 1944 n.a. n.a. MT633881 MT649971
BPI 870274 Hordeum vulgare USA, Pennsylvania 1944 n.a. MT633926 MT633847 MT650014 BPI 563019 Hordeum vulgare USA, West Virgia 1954 n.a. n.a. MT633856 MT649967
BPI 563048 Hordeum vulgare subsp. vulgare (Hordeum vulgare ROU, Ilfov-Bucuresti 1933 n.a. n.a. n.a. MT649976 var.tetrastichonvulgar) BPI 562951 Leymus condensatus (Elymus condensatus) USA, Wyoming 1941 n.a. n.a. n.a. MT649954
BPI 562830 Pseudoroegneria spicata (Agropyron spicatum) USA, Washington 1935 n.a. n.a. n.a. MT649931
BPI 563286 Triticum aestivum MEX, n.a. 1966 MT622274 n.a. MT633904 MT650009 Blumeria sp. DAOM 82542 Deschampsia cespitosa FIN, Lapponia 1958 MT622281 MT633922 n.a. MT650023 enontekiensis BPI 562901 Bromus japonicus ROU, Lapusna-Cornesti 1931 n.a. n.a. n.a. MT649942 BPI 562983 Holcus lanatus ROU, Vlasca-Comana 1930 n.a. n.a. n.a. MT649960 a. Specimens in bold were included in the concatenated sequence analyses; superscript HT = holotype, ET = epitype. b. Names in parentheses were records on specimen packets. c. Three-letter country codes used: AUS Australia, CAN Canada, CHN China, CZE Czech Republic, DEU Germany, EGY Egypt, ETH Ethiopia, FIN Finland, GBR United Kingdom, DEU Germany, IND India, IRL Ireland, ISR Israel, JPN Japan, LVA Latvia, MEX Mexico, NLD Netherlands, ROU Romania, RUS Russia, UKR Ukraine, GBR United Kingdom, USA United States
Advance Publication
- 73 -