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 Add this item to the list   Pleurotus ostreatus Jacq. ex Fries
Page number:347 
Description type:Culture description 
Description:Pleurotus ostreatus Jacq. ex Fries
Cultural characters: (PI. VII, Fig. 4; Pl. VIII, Figs. 7 to 9).
Growth characters. Growth moderately rapid, plates covered in three weeks. Advancing zone even, raised aerial mycelium extending to limit of growth. Mat white, slightly raised, cottony in newest growth, then collapsed, woolly-felty, with slightly raised tufts arranged in more or less concentric zones, producing somewhat zonate appearance, and with small masses of compactly arranged mycelium around edge of Petri dish in some isolates, from which may develop abortive or, occasionally, mature hut distorted fruit bodies. Reverse unchanged or bleached after three to four weeks. Odor slight, fragrant. On gallic acid agar diffusion zones moderately strong, on tannic acid agar no diffusion zones, no growth on either medium. (See Davidson, Campbell, and Blaisdell (64).)
Hyphal characters. Advancing zone: hyphae hyaline, nodose-septate, frequently branched, 2.2-7.5 µm diameter, usually broad. Aerial mycelium: (a) hyphae as in advancing zone, usually 2.2-4.5 µm diameter, frequently broken up into short segments; (b) fiber hyphae, with walls thick and refractive, the lumina visible only at bases of branches, frequently branched, 1.5-2.2 µm diameter. Submerged mycelium: hyphae as in advancing zone.
Type of rot: white flaky rot of sapwood and heartwood of broad-leaved or, rarely, coniferous trees.
Descriptions of cultural characters: Badcock (3), Cartwright and Findlay (52, 55, 56), Davidson, Campbell, and Blaisdell (64), Davidson, Campbell, and Vaughn (67), Edgecombe (69); Humphrey and Siggers (92).
The three isolates of Pleurotus ostreatus used in this study all gave positive reactions on gallic acid agar, negative reactions on tannic acid agar, but Davidson, Campbell, and Blaisdell (64), using a larger number of cultures, found the most usual reaction on tannic acid agar was a positive one, agreeing with the positive reaction on gallic acid agar. In each of the eight places in which P. ostreatus appears in the key it falls with several other species with identical key patterns. In these cases separations can be made only on the basis of differences in macroscopic Cultural characters.
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