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 Add this item to the list  Fomes igniarius (L. ex Fries) Gill.
Page number:325 
Description type:Culture description 
Description:Fomes igniarius (L. ex Fries) Gill.
Cultural characters: (Pl. III, Fig. 4; Pl. IV, figs. 16 to 19).
Growth characters. Growth moderately rapid to slow, plates covered in four to five weeks. Advancing zone even, white, with raised aerial mycelium extending to limit of growth. Mat white with tinges of "cream-buff" (3.OY8.3/4.5), "chamois" (2.OY7.5/5.8), "Naples yellow" (3.OY7.8/5.0), and "mustard yellow" (2.OY7.8/7.5) (one week), remaining pale or assuming deeper colors of "honey yellow" (2.OY6.7/6.2), "olive-ocher" (3.OY6.8/6.5), and "tawny-olive" (8.OYR4.8/5.8) (two weeks), to "buckthorn brown" (8.OYR4.8/6.5) (three weeks), (a) downy at margin, to cottony and woolly in older parts, with whole surface finally covered with uniform woolly to felty mycelium, or (b) with some zones with scanty
cottony mycelium, white to "honey yellow" (2.OY6.7/6.2) and "yellow ocher" (10 OYR 6.8/9.0) over dark brown crustose areas in agar, remainder of the mat cottony to felty, mycelium frequently heaped up at the edge of the crustose areas. Reverse unchanged to the end of two to four weeks, then patchy, with scattered lines and dots of "ochraceous-tawny" (6.OYR4.9/6 3), "cinnamon-brown" (5.OYR3.0/3.0), "mummy brown" (7.5YR2.5/2.3), etc., finally all brown usually with darker lines and dots, producing a marblelike effect. Odor of wintergreen slight in some isolates, lacking in others. On gallic and tannic acid agars diffusion zones weak to strong, no growth or only a trace on both media.
Hyphal characters. Advancing zone: hyphae hyaline, with inconspicuous simple septa, frequently branched, 1.5-6.0 µm diameter. Aerial mycelium (peels readily from agar and turns brown in potassium hydroxide): (a) hyphae as in advancing zone; (b) fiber hyphae, with walls more or less thickened, greenish-yellow to brown, rarely branched, aseptate, 1.0-3.0 µm diameter; (c) broad hyphae observed in some isolates, with walls slightly thickened, us brown, branched, frequently septate, up to 9.0 µm diameter; (d) cuticular cells arising as irregular swellings on hyphae, at first hyaline with contents staining in phloxine, then dark brown and apparently empty, closely packed together to form a pseudoparenchymatous layer, observed in most isolates. Submerged mycelium: (a) hyphae as in advancing zone; (b) some broad hyphae as in (c) above.
Type of rot: white rot of broad-leaved trees.
Descriptions of cultural characters: Campbell (42), Cartwright and Findlay (55, 56), Davidson, Campbell, and Blaisdell (64), Fritz (74), Hopp (87), Humphrey and Siggers (92), Noecker (118), Verrall (149).
Verrall (149) studied a large number of cultures of Fomes igniarius from various hosts and found that they fell into three groups, one consisting of isolates from Populus spp., one from Betula spp., and one from miscellaneous hosts. The form on Populus spp. was segregated by Campbell (42) under the name Fomes igniarius var. populinus and this practice has been followed in the present study. The isolates from hosts other than Populus spp. showed considerable variation, but no more than that exhibited by individual isolates at different times. Hence no correlation of growth type with host seemed possible, and all the cultures were included under Fomes igniarius In preparing a description of the species, an attempt has been made to include this range in growth characters. Separation from other species having the same key pattern must be on the basis of color and topography, as noted in the descriptive key.

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