Erysiphe viburni Duby [2000108]

Data Set Maintenance: Data set compiled and standard item. Data set author(s): Kainz C. (00-07-27). Data set reviewer(s): Schubert K. (06-03-29); revised.

Nomenclature: Current taxonomic status: accepted or basionymous. Taxonomic rank: species. Synonyms: Microsphaera sparsa Howe; Erysiphe viburni Schwein.; Microsphaera viburni Howe nom. nov.; Microsphaera viburni (Duby) S. Blumer; Erysiphaceae Tul. & C. Tul.; Erysiphales.

Type Information: Basionym: Erysiphe viburni Duby. Type: Erysiphe viburni Duby.

Taxonomic Literature: Taxonomic notes: +appressoria multilobed, opposite or single, 3-12 µm wide;+conidiophores foot-cells straight or occasionally flexuous below, followed by 1-2 shorter cells;+ascomata outer wall cells obscure, polygonal, ca. 10-20 µm diam.;. Braun U., Beih. Nova Hedwigia 89: 1-700 [416-417] (1987); Braun U., The powdery mildews (Erysiphales) of Europe. - 1-337. Jena, Stuttgart, New York (1995).

Biogeography: Continent: Asia-Temperate, Australasia, Europe (all), and Northern America (USA, Canada). Region(s): Siberia, Far Eastern Asia, China (and Central Asia), and New Zealand (introduced). Country or state(s): Denmark, Finland, United Kingdom, Norway, Sweden, Austria, Benelux (Belgium & Luxembourg), former Czechoslovakia (incl. Czech Republic & Slovacia), Germany, Hungary, Netherlands, Poland, Switzerland (incl. Liechtenstein), France (excl. Corsica), Bulgaria, Italy (incl. San Marino & The Vatican City, excl. Sicily, Sardinia), Romania, European Turkey, Belarus, Baltic States (Estonia, Lithuania, Latvia), and Ukraine; Japan; India; Ontario (Canada), Colarado (USA), Illinois (USA), Iowa (USA), Minnesota (USA), Missouri (USA), North Dakota (USA), South Dakota (USA), Wisconsin (USA), Connecticut (USA), Indiana (USA), Massachusetts (USA), Michigan (USA), New Hampshire (USA), New Jersey (USA), New York (USA), Ohio (USA), Pennsylvania (USA), Vermont (USA), West Virginia (USA), Delaware (USA), Florida (USA), Georgia (USA), Maryland (USA), Mississippi (USA), North Carolina (USA), Virginia (USA), and District of Columbia (USA).

Ecology: Biotroph; phytopathogenic; growing on leaves, hypophyllous (often) or amphigenous. Host or Phorophyte Taxonomy: Viburnum lentago L.; Viburnum, Caprifoliaceae.

Reproduction Strategy: With sexual (and possible asexual) stages. Ascocarps: Cleistothecioid, orbicular, forming independently from the host thallus or mycelium, scattered or in loose groups, (.075)-.08-.11-(.125) mm in diam.. Margin: External filaments present; not interlaced, recurved (tips of the ultimate branchlets distinctly recurved), (.5)-1-1.5-(2) µm long, 5-10 µm in diameter, hyaline or pigmented (at the base), few or numerous, 4-16 per mm², growing between the lower and upper hald of the ascocarp, stiff and straight (mostly curved), rough, thin, moderatly thick (throughout or thin-walled above and thick-walled towards the base), or thick, ramified, dichotomously branched ((3-)4-5(-6) times, branches regular, close and compact or often looser, primary branches characteristically elongated, horizontally spread, tips of the ultimate branchlets distinctly recurved), aseptate or septate (1-2 septa at the base).

Asci: 3-8 asci per ascocarp, not stipitate or indistinctly stipitate, 40-60 µm long, 30-50 µm wide; dehiscence unitunicate.

Ascospores: c. 4 to c. 8 per ascus, spores 4-8 per ascus, subglobose, ellipsoid, or ovoid, (15)-18-25 µm long, 10-16 µm wide; septa absent.

Conidiomata: Present; hyphomycetous.

Conidiophores: Pseudoidium-type; not branched; basal cells 30-85 µm long, (5)-5.5-7.5 µm wide. Conidium Formation: Conidiogenous cells single. Conidia: More or less cylindrical; macroconidial (germ tubes on an end, short to moderately long, ending in an multilobed appressorium), not branched, (30)-35-37-(47.5) µm long, (11)-15-17-(18) µm wide; aseptate.

(report generated 04.Okt.2007)