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 Add this item to the list  Polyporus squamosus Huds. ex Fries
Page number:232 
Description type:Culture description 
Description:Polyporus squamosus Huds. ex Fries
Culture examined: FRI 308: Context culture, Isolated from 6517 on Populus sp. stump, causing white stringy rot.
Growth characters. - Rate of growth very slow, the radius at 1 week 0.8-0.95 cm, at 5 weeks 6.4-7.0 cm. Advancing zone even, hyaline, and appressed or slightly raised aerial mycelium extending to limit of growth. Mat at first appressed with scanty aerial mycelium, thinfelty around inoculum, white, after 3--6 weeks in some areas short cottony, floccose, floccose-short woolly, fioccose-felty to thin felty, white to `pale olive buff', in other areas skinlike `drab', `buffy brown', `saccardo's umber', `raw umber', 'brussels brown' and `sépia'. Reverse unchanged `light drab' below skinlike area. Odour strong, disagreeable (of bed bugs).
Tests for extracellular oxidase positive: on gallic and tannic acid agars diffusion zones strong and moderately strong respectively and no growth on either medium; with guaiacum reaction very strong.
Hyphal characters. - Advancing zone: hyphae hyaline, thin-walled, nodose-septate branched, 2.0-5.5 µm in diameter. Aerial mycelium: (a) hyphae as in advancing zone, sometimes broken up at nodes or between rodes; (b) hyphae slightly thick-walled, light brown, sometimes divided into many short cells by simple septa; (c) some hyphae with short, bulging, sometimes irregular, slightly thick-walled, cells upto 7.5 µm broad; (d) in skinlike layer, hyphae slightly thick-walled, septate, with many short branches and protuberances, firmly interlocked to form a pseudoparenchymatous layer. Submerged mycelium: hyphae as in advancing zone.
References: Cartwright and Findlay (1942, 1958) and Nobles (1948). Oidia reported by the authors were rot observed in the present isolate.
The fungus may be easily recognised in culture by its slow rate of growth, colour of the mat, positive tests for extracellular oxidase and the skinlike layer composed of thick-walled and septate hyphae with many short branches and knob-like protuberances.

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