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 Add this item to the list  Dentipellis dissita
   
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Page number:41 
Remarks (internal):This is the first description of the cultural characters and mating system of a species of Dentipellis. The diagnostic cultural characters for D. dissita are the floccose growth, chlamydospores, crystalline incrusted hyphal segments, gloeocystidia (except in 6802), gloeopleurous hyphae and resinous droplets on the surface of some hyphae.
Although the different isolates were remarkably similar there were some noticable variations that presented difficulties in circumscribing the species in culture. For example, gloeocystidia were produced in all isolates except 6802, moniliform hyphal cells were seen only in 5059, and resinous droplets occurred in all except 134050.
The reactions of the various tests for laccase were predominantly positive even though the intensity of the reaction was typically weak. The negative reactions (one isolate with guiacol and four on tannic acid agar) may indicate that the quantity of laccase was too low to be detected in these tests.
Haploid matings between collections 190893, 190988, 3795 and 11683 were compatible, i.e., clamp connections were formed, indicating that all were of the same species.
 
Description type:Culture description 
Description:Dentipellis dissita
Culture: Growth at 25°C at an intermediate rate, the mats covering the 85 mm plates in 4 weeks. Mats at 2 weeks 35-40 mm in radius, white, somewhat variable in texture, either sparsely cottony-floccose, to 1 mm thick on older parts, raised 2(-3) mm just behind the margin or rather densely cottony-floccose, 3-4 mm thick with some sparsely cottony patches; margin even, thin, sparse, appressed and submerged, of distinct radiating hyphae. Mats at 4 weeks sparsely to densely cottony-floccose, raised 1-3 mm, with some small patches where the mat is sparse and appressed, mycelium growing up the sides of the dishes. At 6 weeks mats as above but culture 190893 with scattered, pure white, woolly-cottony hyphal clumps 3 mm diam. Odor typically slightly sour throughout the growth period but lacking in 190988 and 5059. Reverse unchanged or in 5059, 134050 and 190988 with slight to moderate yellowing, especially under the outer third of the mat. Tests for tyrosinase (Käärik 1965) with p-cresol and tyrosine were negative, except for a weak pale orange discoloration of p-cresol after 1 hour on 1475 and 6802. Tests for laccase with syringaldazine (Harkin et al. 1974), gum guaiacum (Nobles 1965), gallic acid agar (Nobles 1965) were positive. Guaiacol (Käärik 1965) produced a pale yellow orange color, which was judged to be a positive reaction, on all isolates except 191437. On tannic acid agar (Nobles 1965) there was no or only very faint staining. and no growth. On gallic acid agar the staining was weak to moderate. Only isolates 5059, 6802, 103988 and 134050 produced some mycelium.
At 2 weeks the advancing edge with broad (4-8 µm diam), hyaline, thin-walled, radiating hyphae which were infrequently branched and with single clamp connections; the apical cells about 4 µm diam and these hyphae gradually broadening posteriorly, the apical cells 130-170 µm long. Aerial hyphae hyaline, thin-walled, 1-7 µm diam with single clamp connections, the 1 µm diam hyphae were 5-6 cells long and were the gradually attenuated tips of hyphal branches which were 3 µm diam at the base, not reacting in Melzer's reagent; some gloeopleurous hyphae 2.5-7 µm diam, rare to scattered, as intercalary, branched cells, about 300 µm long, pale yellow, refractive, homogenous cytoplasm which stained pink in phloxine but did not darken in sulphobenzaldehyde; the clamp connections were prominent and some were slightly inflated; at 6 weeks resinous droplets rather common on the surface of the hyphae. Adnate and submerged hyphae similar to the aerial hyphae but 2-5 µm diam, rather frequently branched and a few incrusted with crystals or resinous droplets, only in 5059 were moniliform hyphal segments present. Chlamydospores scattered at 2 weeks, more common later,terminal and intercalary, fusoid to clavate, finally subglobose, about 7-10 x 6-8 µm, the walls hyaline, to 1µm thick, smooth. Gloeocystidia typically scattered to common, lacking only in 6802, arising from the aerial hyphae, terminal cells, lanceolate, slenderly clavate, with the apex obtusely rounded, acute, moniliform or papillate, 100-400 x 4-5 µm, and 3 µm diam at the basal clamp connection, infrequently weakly branched, the contents oily, yellow, refractive, not staining in sulphobenzaldehyde. Basidia at 6 weeks in 190893 found in the woolly-cottony clumps, very few, 2-3-4 sterigmate, produced singly; no basidiospores seen.
Species code (Nobles 1965): 2a.3.(15).(21).34.36. 38.44. (48) .54.59.
Mating system: Unifactorial (i.e., bipolar).
 
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