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 Add this item to the list  Fomes fraxineus (Bull. ex Fries) Cooke
Page number:323 
Description type:Culture description 
Description:Fomes fraxineus (Bull. ex Fries) Cooke
Cultural characters: (PI. III, Fig. l; Pl. IV, Figs. 1 to 6).
Growth characters. Growth moderately rapid, plates covered in three to four weeks. Advancing zone even, hyaline, appressed, silky. Mat white, cottony near margin, becoming felty and irregularly thickened, usually 'corroded' in appearance, sometimes with drops of exudate over surface, fruiting in some isolates after three to four weeks in organized pored areas or in inconspicuous groups of basidia scattered over surface. Reverse unchanged. Odor none. On gallic and tannic acid agars diffusion zones weak to moderately strong, no growth on gallic acid agar, trace to 1.5 cm. diameter on tannic acid agar.
Hyphal characters. Advancing zone: hyphae nodose-septate, 1.5-6.0 µm diameter. Aerial mycelium: (a) hyphae as in advancing zone; (b) fiber hyphae numerous, walls thick, lumina narrow or apparently lacking, branched, aseptate, 1.5-4.5 µm diameter; (c) chlamydospores numerous, terminal and intercalary, globose to ovoid with walls noticeably thick and often appearing sculptured, 10.5-16.5 x 7.5-12.0 À¬m; (d) hyphae with tips branched dichotomously in staghorn or coralloid effect, observed in some isolates; (e) cuticular cells, hyaline, empty, forming a thin pseudoparenchymatous layer, observed in F7519 only. Fruit body: (a) basidia 7.5-10.5 µm diameter, each bearing four spores; (b) basidiospores hyaline, even, subglobose or broadly ovoid, apiculate, with conspicuous oil drop, 5.4-6.0 µm diameter, observed in large numbers in old cultures, apparently empty. Submerged mycelium: (a) nodose-septate hyphae and (b) chlamydospores as described above.
Type of rot: white rot of broad-leaved trees, especially Fraxinus spp.
Descriptions of cultural characters: Badcock (3), Baxter (6), Campbell (42), Cartwright and Findlay (51, 55, 56), Davidson, Campbell and Blaisdell (64), Montgomery (107).
Cultures of Fomes fraxineus that form cuticular cells fall alone in the key, but the more numerous isolates lacking these have key patterns identical with those for several other species. The inserted descriptive keys mention typographical and microscopic- differences that should make separation possible. The chlamydospores of Fomes fraxineus, with thick sculptured walls, are distinctive.
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