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 Add this item to the list  Polyporus gilvus Schw. ex Fries
Page number:223 
Description type:Culture description 
Description:Polyporus gilvus Schw. ex Fries
Culture examined: FRI 648: Polysporous culture, Isolated from 7435 on oak stump, causing white rot.
Growth characters. - Rate of growth very slow, the radius at 1 week 0.6-1.0 cm; at 2 weeks 1.6-2.0 cm. at 3 weeks 2.8-3.4 cm, at 4 weeks 4.0-5.0 cm. Advancing zone at first even, after 3-4 weeks bayed, slightly raised aerial mycelium extending to limit of growth. Mat at first appressed, slightly raised to short cottony, white to `cream-buff', after 3--6 weeks appressed to slightly raised in newer growth, becoming compact and felty in older growth, `cream-buff', 'chamois', `sayal brown', `snuff Brown' to `saccardo's umber'. Poroid fruiting surface is formed in old cultures. Reverse unchanged or `sayal brown' to `buckthorn brown' below coloured arecs and 'prout's brown' below inoculum. Odour none.
Tests for extracellular oxidase positive: on gallic acid agar diffusion zones very strong and no growth or trace of growth; on tannic acid agar diffusion zones strong, diameter 2.3-2.7 cm; with guaiacum reaction strong.
Hyphal characters. - Advancing zone: hyphae hyaline, thin-walled, simple-septate, branched, 1.5-4.3 µm in diameter. Aerial mycelium: (a) hyphae as in advancing zone, sometimes with walls slightly thickened and yellow; (b) hyphae thick-walled, brown, sparsely branched, 1.8-4.3 µm in diameter; (c) hyphae with short, bulging cells, with slightly thickened and yellow walls, upto 9.2 µm wide, observed in old cultures. Fruit-body: (a) brown hyphae as in aerial mycelium; (b) setae present, less common, thick-walled, brown, 8.5-24.4 x2.5-4.3 µm (basidia and basidiospores not found). Submerged mycelium: hyphae as in advancing zone.
References: Davidson, Campbell and Vaughn (1942) and Nobles (1948). The occurrence of rare nodose-septate hyphae in some cultures as observed by Nobles (1948) was not found in the present isolate. The present isolate also differs from previous descriptions in having short bulging cells on hyphae in old cultures.
P. gilvus may be readily recognised in culture from the topography and colour of the mat, simple-septate hyphae, the presence of setae in the fruiting arecs and rare formation of basidia and basidiospores.

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