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 Add this item to the list  Polyporus adustus Willd. ex Fries
Page number:350 
Description type:Culture description 
Description:Polyporus adustus Willd. ex Fries
Cultural characters: (PI. VII, Fig. 7; Pl. VIII, Figs. 15 to 18).
Growth characters. Growth rapid, plates covered in two weeks. Advancing zone even, slightly raised aerial mycelium extending to limit of growth. Mat white or with tinge of "cream-buff" (3.0Y8.3/4.5) after three to four weeks, cottony-woolly to woolly-floccose in newest growth, finally collapsed and felty, in some isolates so thin as to be translucent. Reverse unchanged or bleached after three to four weeks. Odor slight, "faintly fragrant". On gallic acid agar diffusion zones lacking (may be slight browning of agar), diameter 1.5-3.5 cm.; on tannic acid agar no diffusion zones, no growth.
Hyphal characters. Advancing zone: hyphae hyaline, nodose-septate, profusely branched, 2.2-4.5(-6.0) µm diameter. Aerial mycelium: (a) hyphae as in advancing zone; (b) oidia formed by fragmentation of nodose-septate hyphae or of branches with simple septa, 2.2-3.0 µm diameter, of lengths varying from 2.0-15.0 µm. Submerged mycelium: hyphae as in advancing zone, frequently irregular, with numerous short branches, projections, and swellings.
Type of rot: white mottled or cubical rot of broad-leaved or, rarely, coniferous trees.
Descriptions of cultural characters: Badcock (3), Bose (32), Cartwright (49), Cartwright and Findlay (51, 56), Davidson, Campbell, and Blaisdell (64), Vandendries (144).
This differs from other descriptions of the species, which have omitted mention of oidia or have described them as being restricted to monosporous cultures (Vandendries (144)), and have reported the occurrence of chlamydospores (Cartwright (49) ) and of conidia (Bose (32) ). In the present study oidia in abundance were observed on nodose-septate hyphae in five of the isolates examined. The remaining isolate (9208) appeared to have lost vigor, in that it produced almost no aerial mycelium and, perhaps correlated with this, no oidia. The other types of secondary spores reported by Cartwright (49) and Bose (32) were not observed, although this apparent discrepancy may be the result of differences in interpretation of the method by which the spores are produced rather than of actual differences in the cultures.
If oidia are observed and their presence included, then the key pattern of P. adustus is different from that of any other species. If oidia are omitted, then its key pattern coincides with those for P. betulinus and P. dichrous, from which separations can be made only on the basis of differences in topography and in the degree of inhibition of growth by gallic and tannic acid agars.
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