Erysiphe digitata (A. J. Inman & U. Braun) A. J. Inman & U. Braun

Data Set Maintenance: Data set compiled and standard item. Data set author(s): Schubert K. @EXCL@ Kainz C. (06-03-21).

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

Type Information: Basionym: Microsphaera digitata A. J. Inman & U. Braun. Type: Microsphaera digitata A. J. Inman & U. Braun.

Taxonomic Literature: Taxonomic notes: + ascomata outer wall cells irregularly polygonal, 14-34 × 10-20 µm. Inman A.J., Cook R.T.A. & Beales P.A., J. Phytopathology 148: 17-27 (2000).

Biogeography: Continent: Europe. Country or state(s): Benelux (Belgium & Luxembourg).

Ecology: Biotroph; phytopathogenic; growing on leaves, hypophyllous. Host or Phorophyte Taxonomy: Rhododendron mekongense var. melinanthum (Balf.f. & Ward) Cullen; Rhododendron, Ericaceae.

Reproduction Strategy: With sexual (and possible asexual) stages. Ascocarps: Cleistothecioid (dark brown), orbicular, scattered or in loose groups, (.08)-.09-.1-.115 mm in diam.. Margin: External filaments present; straight, (180)-200-298-350-(625) µm long, 4-7-(8) µm in diameter, hyaline (subhyaline to pale brown, pigmentation not confined to the base but spreading towards the apex) or pigmented, few or numerous, 9-25 per mm², growing between the lower and upper hald of the ascocarp (subequatorial to rarely equatorial, horizontally spread), flexuose (curved to) or geniculate (bent) (somewhat sinuous, occasionally geniculate), smooth or slightly verrucose ((by SEM)), thin or moderatly thick (becoming gradually but only moderately thicker walled (but still less than 2 µm thick) towards the base), ramified, dichotomously branched ((3-)4-6 times, mostly irregular, branching rather loose and wide usually with elongated primary and often secondary branches, rarely forked in the lower half, higher order branches often characteristically wavy, ultimate branches often finger-like), aseptate or septate ((0-)1-4(-7)-septate, septa not restricted to the base but usually reaching the upper half).

Asci: (3)-4-6-(8) asci per ascocarp, globose (oval to oval-ellipsoid), not stipitate or indistinctly stipitate, (42)-46-58-69 µm long, 30-38-46 µm wide; dehiscence unitunicate.

Ascospores: c. 4 or c. 8 per ascus, spores (3)-4-6-(7) per ascus, ellipsoid or ovoid, 18-23-26-(29) µm long, 10-12-14 µm wide; septa absent.

Conidiomata: Present; hyphomycetous.

Conidiophores: Pseudoidium-type; not branched (foot-cells short, followed by one to two additional cells or none); basal cells (18)-26-34-43-(50) µm long, 6-9-12 µm wide. Conidium Formation: Conidiogenous cells single or in chains (sometimes remained attached in short chains when mature). Conidia: Ellipsoid or cylindrical; macroconidial (length/width ratio 1,8 to 3,2 (2,35); in the SEM, conidia showed longitudinal wrinkling patterns on the outer walls and evidence of a fibrillar, 'basket weave' pattern on the end wall), not branched, 26-34-42-(46) µm long, 11-14.5-17-(19) µm wide; aseptate.

(report generated 04.Okt.2007)