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 Add this item to the list  Polyporus sulphureus Bull. ex Fries
Page number:233 
Description type:Culture description 
Description:Polyporus sulphureus Bull. ex Fries
Culture examined: FRI 310: Context culture from 6505 on living Cedrela tonna Roxb., causing brown cuboidal rot in heartwood.
Growth characters. - Rate of growth moderately rapid, the radius at 1 week 3.7 cm. Advancing zone even, hyaline, appressed or with tufts of slightly raised mycelium forming a broad zone. Mat at first slightly raised, short cottony to cottony towards newer growth and floccose-farinaceous in the remaining area, white to `light buff', after 3-6 weeks floccose-farinaceous, woolly-farinaceous and farinaceous,`pale ochraceous-buff',`cream colour', to`cream-buff'. Reverse unchanged. Odour none.
Tests for extracellular oxidase negative: on gallic and tannic acid agars no diffusion zones, diameter 7.0-8.0 cm. on both media; with guaiacum no reaction.
Hyphal characters. - Advancing zone: hyphae hyaline, thin-walled, simple-septate, 3.0-6.0 µm in diameter. Aerial mycelium: (a) hyphae as in advancing zone; (b) conidiophores numerous, composing most of the aerial mycelium, 1.8-3.0 µm in diameter, much branched, each branch bearing a single conidium at the end; (c) conidia numerous, giving the aerial mycelium a powdery appearance, thin-walled, subglobose to ovoid, 4.3-7.3 x 4.3 x 6.1 µm; (d) chlamydospores numerous with walls slightly thickened, terminal and intercalary, 5.1-11.0 x 4.9-7.3 µm. Submerged mycelium: (a) hyphae as in advancing zone; (b) chlamydospores as in aerial mycelium.
References: Cartwright and Findlay (1942, 1958), Davidson, Campbell and Vaughn (1942), Fritz (1923) and Nobles (1948).
Fritz and Davidson, Campbell and Vaughn considered all the secondary spores as chlamydospores whereas Cartwright and Findlay and Nobles described smaller spores borne terminally ou ride branches of much branched aerial hyphae (conidiophores) as conidia and Nobles considered the slightly thick-walled larger spores as typical chlamydospores. Nobles' interpretation has been followed in the present work.
The fungus can be very easily recognised in culture by its characteristic raised granular and fluffy mat showing buff shades of colour and consisting of a mass of secondary spores.

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