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 Add this item to the list   Polyporus amorphus Fries
Page number:213 
Description type:Culture description 
Description:Polyporus amorphus Fries
Culture examined: FRI 451: Polysporous, Isolated from 6629 on Pinus roxburghii Sargent, log, causing white rot in sapwood.
Growth characters. - Rate of growth very slow, the radius at 1 week 1.0 cm., at 2 weeks 2.2 cm., at 3 weeks 3.6 cm., at 4 weeks 5.0 cm. and at 5 weeks 6.3 cm. Advancing zone even, hyaline and appressed. Mat at first appressed and white, after 2 weeks appressed and white behind advancing zone, floccose-felty in the middle zone and irregularly poroid over and around inoculum, white, with glistening drops of exudate on the surface in poroid area, after 3-4 weeks floccose-felty to compact felty with surface farinaceous or poroid forming fruiting area, white or faintly cream-coloured in older parts of fruiting area, drops of exudate scattered on the surface in poroid area. Reverse unchanged. Odour faint.
Tests for extracellular oxidase positive: on gallic acid agar diffusion zones very strong with no growth; on tannic acid agar diffusion zones moderately strong to strong with no growth; with guaiacum reaction weak to moderately strong.
Hyphal characters. - Advancing zone: hyphae hyaline, nodose-septate, thin walled, branched, 1.5-4.0 µm in diameter. Aerial mycelium: (a) hyphae as in advancing zone, thin to slightly thick-walled; (b) fibre hyphae numerous, with walls thick and refractive and lumina narrow or apparently lacking, unbranched, 2.4-3.0 µm in diameter. Fruit body: (a) basidia clavate, 3-4 µm in diameter, bearing four spores; (b) basidiospores hyaline, even, allantoid, guttulate, 3-4 x 1.0-1.5 µm. Submerged mycelium: hyphae as in advancing zone.
Reference: Nobles (1948).
The fungus is characterised in culture by its very slow rate of growth and the formation of pores on the surface of mat over a considerable area.

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