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Remarks (public):For a complete description including images see www.cababstractsplus.org/dfb 
Remarks (internal):Caused 10% reduction in yield in Austria in 1986.
 
Description type:Non-original description 
Description:Ramularia collo-cygni B. Sutton & J. Waller, Transactions of the British Mycological Society 90: 57, 1988.
Ophiocladium hordei Cavara, 1893.
Ovularia hordei (Cavara) Sprague, 1946.
Ramularia hordeicola Braun, 1988.
Leaf lesions linear to lenticular, up to 1-3 mm long, 0,3 mm wide, evenly pale to medium brown, on some hosts darker brown, lacking a definite margin. Mycelium immersed, sparse, formed of septate, hyaline, branched hyphae colonizing the mesophyll. Stromata substomatal, up to 30 µm diam., composed of hyaline to very pale brown, thin-walled textura angularis.Caespituli hypogenous, very rarely epigenous, linearly arranged between leaf veins, whitish-pink, dry, discrete, rarely confluent. Conidiophores 30-56 µm long (including the recurved region), arising in caespituli of up to 15 through the stomatal openings or as lateral or upright branches from suprastomatal cells, hyaline, smooth, simple or branched 1-3 times at the base, less frequently branched 15-20 µm from the base, lax, thin-walled, frequently collapsing, vertical or recumbent on the leaf surface, 1-3-septate towards the apex and curved back for 8-14 µm towards the main axis of the conidiophore, with the conidiogenous region slightly swollen to 3 µm wide. Conidiogenous cells integrated, apical, geniculate, with 1-5 polyblastic loci, indeterminate, smooth, hyaline, with conspicuously thickened, flat, non-protuberant scars restricted to the swollen apical region. Conidia holoblastic, hyaline, verruculose, aseptate, oval to ellipsoid, with a flat, conspicuously thickened, slightly excentrically situated scar near the base, 9,5-11,5 x 4,5-6 µm.
Hosts: Glyceria grandis, Hordeum vulgare, Phalaris arundinacea, Triticum secalum (Triticale).
Disease: Leaf and awn spot of Gramineae, especially winter and summer barley.
Geographical distribution: Europe: Austria. North America: Mexico, USA.
Physiological specialization: Not known
Transmission: Wind and water dispersed.
Literature: Sutton & Waller, Trans. Br. mycol. Soc. 90: 55-61, 1988; Huss, Mayrhofer & Wetschnig, Der Pflanzenarzt 40: 167-169, 1987.

 
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