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Page number:364 
Description type:Non-original description 
Description:Alternaria smyrnii (Crouan) E.G. Simmons, Mycotaxon 55: 41. 1995. - Fig. 150A, B
? Helminthosporium smyrnii Crouan, in P.L. Crouan and H. M. Crouan, Florule du Finistère, p. 11. 1867.
? Macrosporium smyrnii (Crouan) Saccardo, Syll. Fung. 4: 527. 1886.
= Stemphylium ramulosum Saccardo, Michelia 1: 360. 1878.
= Macrosporium ramulosum (Sacc.) Sacc., Fungi italici autogr. del. no. 854. 1881.
= Alternaria ramulosa (Sacc.) Joly, Encycl. Mycol. 33: 213. 1964.
Type (neotype, designated Simmons 1995): CO (sur les tiges mortes du Smyrnium olusatrum. hiv. Print. p.c. (vv); E.G.S. 30.028)
Host/substrate: Smyrnium olus-atrum L., Anthriscus sylvestris (L.) Hoffm.. Petroselinum crispum L. (Umbelliferae)
Manual basis: Simmons 1995, Alt.T&V 131 (Fig. 107, 108); representative isolate E.G.S. 37.093, CBS 109380
Culture at 50X, 5-7d, PCA & V-8: colony ca 4 cm diam; growth pattern distinctly radial, without conspicuous concentric rings of growth or sporulation. Sporulation on cut agar surface, 2 d: PCA and V-8, rare or none
Extensive black field colonies of A. smyrnii are composed of open to dense thickets of erect, rigid, shiny black, setose conidiophores. At magnifications higher than 50X, these conidiophores are seen to be very dark brown, thick-walled, and closely septate, arising singly or more often in clumps from enlarged, rough, cellular bases or from multicellular microsclerotia. Conidiophores commonly range 200-300 µm in length to well over 500 µm x ca 11-25 µm wide; they often are conidiogenous at well-separated geniculate sites or from several short, closely consecutive apical cells.
Conidia in the field type are ovoid, with 7-8 slightly constricting, well-defined but not thickened transverse septa and 1-3 longisepta in a few to most of the transverse segments, up to ca 64-96 x 24-27 µm, pale to medium yellowish brown, and smooth. Occasional short, 1-celled apical secondary conidiophores are evidence that chains, probably very short, are produced.
The appearance of A. smyrnii cultures is similar to that of other members of the A. radicina species-group. Short to long erect conidiophores originate at or beneath the agar surface, sometimes as distinguishable individuals in a close turf of sporulating structures and often as clumps arising from conspicuous knots or sclerotial growths of very dark cells formed within or on the agar substrate. Free-standing conidiophores are ca 100-600 (or often much more) x 3-7 µm, dilute yellow-tan, with conidiogenous branches at various levels. The longest conidiophores arch and entangle, forming a loose pseudo-network above the colony. Conidiophores that originate in sclerotial knots do not develop through to spore production within ca 2 weeks of active culture, but eventually do so.
Conidia produced in culture are ovoid (as in field specimens), sometimes obovoid, or to a high percentage narrowly ovoid or ellipsoid, with 7-8 transverse septa in largest ovoid spores, up to 10 transverse septa in narrowly ellipsoid spores, and 1-2 longisepta in a few of the transverse segments. Ovoid and obovoid conidia reach a size range of ca 40-58 x 18-22 µm and the narrower ellipsoid ones, which dominate the population, ca 67-96 x 13-16 µm. Conidia are smooth, occasionally punctulate, and medium brown in color. Chains of two conidia occur commonly, with the generating secondary conidiophore usually a single short cell or sometimes nothing more than a slight apical, aseptate swelling with an apical conidiogenous site.
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