Erysiphe urticae (Wallr.) S. Blumer

Data Set Maintenance: Data set compiled and standard item. Data set author(s): Kainz C. Data set reviewer(s): Schubert K. (06-01-26); revised.

Nomenclature: Current taxonomic status: accepted. Taxonomic rank: species. Erysiphaceae Tul. & C. Tul.; Erysiphales.

Type Information: Basionym: Alphitomorpha urticae Wallr. Type: Alphitomorpha urticae Wallr.

Taxonomic Literature: Taxonomic notes: +ascocarp outer wall cells irregularly polygonal to rounded, ca. 6-20(-25) µm diam.; vegetative hyphae substraight to wavy, 28-75 × 3,5-6 µm, branching at right or narrow angle, with a septum near the branching point; secondary mycelium absent; appressoria multilobed to moderately lobed, opposite in pairs or single. Braun U., Beih. Nova Hedwigia 89: 1-700 [214] (1987); Braun U., The powdery mildews (Erysiphales) of Europe. - 1-337. Jena, Stuttgart, New York (1995).

Biogeography: Continent: Asia-Temperate and Europe. Region(s): Siberia, Middle Asia, and China. Country or state(s): Denmark, Finland, United Kingdom, Norway, Sweden, Austria, 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, Former Yugoslavia [incl. Bosnia and Herzegovina, Croatia, Macedonia, Moldova, Serbia and Montenegro, Slovenia], Belarus, Baltic States (Estonia, Lithuania, Latvia), and Ukraine.

Ecology: Biotroph; phytopathogenic; growing on leaves, amphigenous. Host or Phorophyte Taxonomy: Urtica dioica L.; Urtica, Urticaceae.

Reproduction Strategy: With sexual (and possible asexual) stages. Ascocarps: Cleistothecioid, orbicular, forming independently from the host thallus or mycelium, not emerging (in the mycelial layer), in loose groups or gregarious, (.07)-.095-.13-(.16) mm in diam.. Margin: External filaments present (mostly short, shorter than the cleistothecial diam., sometimes rudimentary; narrow); mycelioid, straight, .5-1.5 µm long, (3)-4-6-(7.5) µm in diameter, hyaline, few or numerous, growing all across the lower half of the ascocarp, smooth, thin, not ramified, septate.

Asci: (3)-5-10-(13) asci per ascocarp, distinctly stipitate, 50-85 µm long, 30-50 µm wide; dehiscence unitunicate.

Ascospores: c. 4 to c. 8 per ascus, spores (3)-5-6 per ascus, ellipsoid or ovoid, (17)-20-25 µm long, 10-16 µm wide; septa absent.

Conidiomata: Present; hyphomycetous.

Conidiophores: Pseudoidium-type; not branched (one or two or occasionally three on a hyphal cell, arising from the upper part of mother cells, pposition mostly non-central, straight at the base of the foot cells, followed by 2-3(-4) cell, foot cells long, with a basal septum displaced up to 10 µm away from the branching point of the mycelium); conidiophore cells 64-164 µm long, basal cells 5-8 µm wide. Conidium Formation: Conidiogenous cells single. Conidia: Ellipsoid, ovoid, or cylindrical; macroconidial (germ tubes subterminal), not branched, 24-36-(48) µm long, 10-15-(20) µm wide; aseptate; without distinct fibrosin body fibrosin bodies.

(report generated 04.Okt.2007)