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Page number:332 
Description type:Culture description 
Description:Fomes roseus (Alb. and Schw. ex Fries) Cooke
Cultural characters: (PI. 111, Fig. 13; Pl. IV, Figs. 46 to 49).
Growth characters. Growth moderately rapid plates covered in three weeks. Advancing zone even, hyaline and appressed so that it is difficult to see limit of growth. Mat white to "tilleul buff" (9.0YR8.7/1.5), "shell pink" (2 0YR8.4/3.7), "light pinkish cinnamon" (7.0YR7.5/4.5), "vinaceous-buff" (7.0YR7.0/3.5), and "vinaceous-fawn (4.5YR6.7/3.5) around inoculum after three to four weeks, downy or farinaceous in some isolates, becoming more compact felty after three to four weeks and forming a granular to irregularly pored fruiting surface. Reverse unchanged or with scattered areas "hazel" (3.0YR3.8/5.0) to "Prout's brown" (5.5YR2.8/3.2) after five to six weeks. Odor slightly fruity. On gallic and tannic acid agars diffusion zones lacking or very weak, diameter 2.0-2.5 cm. on gallic acid agar, trace to 1.5 cm. on tannic acid agar.
Hyphal characters. Advancing zone: hyphae hyaline, nodose-septate, frequently branched, 1.5-4.5(-6.0) µm diameter. Aerial mycelium: (a) hyphae as in advancing zone; (b) fiber hyphae rare to numerous, with walls thick and refractive, lumina narrow or apparently lacking, sparingly branched, apparently aseptate, 2.0-3.0 µm diameter. Fruit body: (a) nodose-septate and (b) fiber hyphae as above; (c) basidia 4.5 µm diameter, bearing four spores; (d) basidiospores hyaline, even, elongate-ellipsoid, slightly curved, 4.5-6.0 x 1.5-2.7 À¬m. Submerged mycelium: (a) hyphae as in advancing zone; (b) crystals numerous, in irregular clumps.
Type of rot: brown cubical rot of coniferous and, rarely, broad-leaved trees.
Descriptions of cultural characters: Campbell (42), Cartwright and Findlay (54), Davidson, Campbell, and Blaisdell (64), Davidson, Lombard, and Hirt (68), Fritz (74), Mounce and Macrae (114), Snell (138), Snell, Hutchinson, and Newton (140).
In the key no code number is allotted to a color change from white to pink and vinaceous, and cultures exhibiting these colors fall with cultures that remain white. Thus the key patterns for Fomes roseus may coincide with those for Pleurotus ostreatus, Polyporus hirsutus, Schizophyllum commune, and others, from all of which separation can usually be made on the basis of color. Cultures of Fomes roseus and F. subroseus are similar and have been separated by Snell, Hutchinson, and Newton (140), and Campbell (42) on the basis of their different rates of growth at certain temperatures. In the present study, in the four cultures of F. roseus examined, no chlamydospores Were observed, while they occurred in all eight cultures of F. subroseus studied. Two cultures filed in the stock culture collection under F. roseus were found to have chlamydospores. On carrying out interfertility tests between these cultures and authentic cultures of F. roseus and F. subroseus it was found that they were interfertile with F. subroseus and therefore belonged to that species and not to F. roseus. This provided additional evidence, but more is required to establish definitely that chlamydospores are regularly present in F. subroseus, absent in F. roseus.
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