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 Add this item to the list  Polyporus rubidus Berk.
Page number:228 
Remarks (public):based on the Indian concept, which is Fomitopsis, cf. Roy & Dee 1996 
Description type:Culture description 
Description:Polyporus rubidus Berk.
Culture examined: FRI 669: Polysporous, Isolated from 7314 on Lagerstroemia sp., causing brown cuboidal rot.
Growth characters. - Rate of growth slow, the radius at 1 week 1.7-1.9 cm., at 2 weeks 3.7-3.9 cm., at 3 weeks 5.4-5.9 cm. Advancing zone even, hyaline, appressed or often raised aerial mycelium extending to limit of growth. Mat white, at first cottony-floccose to woolly-floccose, over inoculum heaped cottony-woolly to woolly, alter 3-4 weeks floccose-cottony, floccosewoolly to floccose-felty, with thin strands of mycelium along the wall of Petri dish Wear inoculum, after 5-6 weeks floccose-woolly, fioccose-felty, woolly-felty to felty. Reverse unchanged. Odour none.
Tests for extracellular oxidase negative: on gallic and tannic acid agars no diffusion zones, diameter 4.0 cm. on the former and 3.5 cm. on the latter; with guaiacum no reaction.
Hyphal characters. - Advancing zone: hyphae hyaline, thin-walled, nodose-septate, branched, sometimes with many short branches towards the hyphal ends, 1.2-4.9 (s in diameter.
Aerial mycelium: (a) hyphae as in advancing zone; (b) fibre hyphae formed in old culture, with thick refractive walls, lumina narrow to apparently lacking, usually branched, sometimes unbranched, 1.2-2.5 µm in diameter; (c) chlamydospores numerous, terminal as well as intercalary, 7.3-13.5 x 3.6-8.5 µm. Submerged mycelium: (a) hyphae as in advancing zone; (b) chlamydospores as in aerial mycelium.
P. rubidus is characterised in culture by white mat, negative tests for extracellular oxidase, nodose-septate hyphae and occurrence of chlamydospores.
P. rubidus and P. atypus are close species. However P. rubidus forms fibre hyphae in old cultures which are lacking in the cultures of P. atypus. Further the optimum and maximum temperatures for growth are higher in P. rubidus than P. atypus. (Sehgal, Sen and Bakshi, 1966).
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