This is an old revision of this page, as edited by M G Tuffen (talk | contribs) at 16:49, 3 October 2007 (merge proposal). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.
Revision as of 16:49, 3 October 2007 by M G Tuffen (talk | contribs) (merge proposal)(diff) ← Previous revision | Latest revision (diff) | Newer revision → (diff) | It has been suggested that this article be merged with Barley stripe (barley) and Talk:Pyrenophora graminea#Merger proposal. (Discuss) Proposed since October 2007. |
| Pyrenophora graminea | |
|---|---|
| Scientific classification | |
| Kingdom: | Fungi |
| Phylum: | Ascomycota |
| Class: | Ascomycetes |
| Order: | Pleosporales |
| Family: | Pleosporaceae |
| Genus: | Pyrenophora |
| Species: | P. graminea |
| Binomial name | |
| Pyrenophora graminea S. Ito & Kurib. 1931 | |
| Synonyms | |
|
Brachysporium gracile var. gramineum (Rabenh.) Sacc. | |
Pyrenophora graminea is the causal agent of barley stripe.
Identification
Asexual stage: Pycnidia are rarely observed in nature. They are 70-176 μm in diameter, globose to pear-shaped, and develop superficially or partly submerged. The wall is thin and fragile and is yellow to brown, with a short ostiole. Pycnidiospores are 1.4-3.2 x 1.0-1.6 μm, spherical or ellipsoidal, hyaline, and nonseptate.
Sexual stage: Perithecia are rare in nature, they occur in barley straw in the autumn. The perithecia are 576-728 x 442-572 μm. They are supeficial to partly submerged and are elongate, with rigid setae on the surface. Acsi are club-shaped or cylindrical, clearly bitunicate, and rounded at the apex, with a short stalk at the base. Ascospores are 43-61 x 16-28 μm, light yellow-brown, ellipsoidal, and rounded at both ends, with transverse septa and one, occasionally two, septum in the median cells but never in the terminal cells.
Conidia are borne laterally and terminally on conidiophores, which usually occur in clusters of three to five. The conidia are straight with rounded ends and measure 11-24 x 30-100 μm. They are subhyaline to yellow-brown and have up to seven transverse septa.
In culture, mycelium is gray to olivaceous and is often sterile. Conidia may be formed when infected barley pieces as placed on water agar and incubated under diurnal light conditions followed by a period of chilling.
Sources
Index Fungorum
USDA ARS Fungal Database
References
- Mathre, D.E. (1997). Compendium of barley diseases. American Phytopathological Society. pp. 120 pp.
 | This fungus-related article is a stub. You can help Misplaced Pages by expanding it. |
 | This plant disease article is a stub. You can help Misplaced Pages by expanding it. |