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Page number:264 
Description type:Culture description 
Description:Fomes roseus (Alb. & Schw. ex Fr.) Karst. (Pl. IV & Pl. IX, 29) Key Pattern; 2 1 2 1 8 2 2 2 3 1 3
GROWTH CHARACTERS.-Growth slow, 2.0 cm in 1 week. Advancing zone hyaline, even, appressed. Mat white, soon becoming `pale vinaceous pink', `shell pink' and `light pinkish cinnamon', farinaceous to floccose, becoming farinaceous-felty after 3 weeks. Poroid fruiting surface covering the whole surface in 4 weeks. Reverse `light ochraceous salmon' to 'light ochraceous buff'. Odour none.
Tests for extracellular oxidase negative; on gallic and tannic acid agars, diffusion zones lacking, growth 2.0 cm on the former and trace to 1.5 cm on the latter, guaiacum reaction nil.
HYPHAL CHARACTERS.-Advancing zone: hyphae hyaline, thin-walled, branched, nodose-septate, 1.5-3.8 µm diameter. Aerial mycelium: (a) hyphae as in advancing zone; (b) fibre hyphae thick-walled, branched, aseptate, 2.0-3.8 µm diameter. Fruitbody: (a) hyphae as in aerial myceliun: (b) basidia clavate, 6.2-15.4 x 4.1-7.714, bearing 4 spores; (c) basidiospores hyaline, smooth, elongate-ellipsoid, 3.0-4.6 x 1.5-2.0 µm. Submerged mycelium: hyphae as in advancing zone.
CULTURES EXAMINED: FRI 41: Context culture, isolated from 3049 on log of Picea smithiana (Wall.) Boiss, and FRI 418: rot culture, on the plank of Abies pindrow Royle, causing brown cuboidal rot.
References: Bakshi (1955), Campbell (1938) and Nobles (1948).
F. roseus is distinguished by pink mat on which poroid area readily develops.
Out of all species of Fomes studied, only F. roseus, F. dochmius, F. pinicola and F. rufolaccatus belong to the group of brown rotters. Pink mat, pore surface on the mat and absence of chlamydospores separate F. roseus from the other three species where mat remains white and chlamydospores develop. Absence of fibre hyphae and slower growth rate distinguish F. dochmius from F. pinicola and F. rufolaccatus where fibre hyphae are present and growth is comparatively faster.
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