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Page number:6 
Description type:Culture description 
Description:CULTURAL CHARACTERS: Growth characters - Growth moderately rapid, plates covered in 3 weeks. Advancing zone sharp, even, mycelium extended to the margin. Aerial mat at first white, thin woolly, later becoming light yellow-brown and subfelty developing fine zonations at the centre and striations towards the periphery. Reverse unchanged initially, later light brown to orange brown. Oxidase test negative on both gallic acid and tannic acid agars. Hyphal characters: Advancing zone - hyphae hyaline, thin-walled, branched, simple septate, 2-3.5 µm wide (Fig.8).
Aerial mycelium - (a) hyphae as in the advancing zone; (b) hyphae thin- to thick-walled, clamped, 2.5-4 µm wide, usually hyaline, (Fig.9), some pale yellow and occurring only in the felty region of the mat, aften repeatedly branched with short swollen branches (Fig.10); (c) fibre hyphae subhyaline to straw yeilow, thick-walled to solid, usually unbranched, few apically biforked, 2.54.5 µm wide (Fig, 11). Chlasydospores subglobose, thick-walled, more commonly terminal, some intercalary, 6-9 x 6.5-12 µm. Oidia cylindric, often with fragment of clamp connections attached at one end, 6-13 x 3-4.5 µm (Fig.12). SEXUALITY: Matings between 15 monosporus cultures of G.sepiarium(86126) showed the species to be heterothallic and bipolar. The monosporus isolates were distributed as
A B 2, 3, 7, 9, 11, 14 11
A B 1, 4, 5, 6, 8, 10, 12, 13 22
This confirms the earlier observations of Nobles (1965). Incidentally, G.striatum (Swartz.:Fr.)Murr., a closely related species is also bipolar (Roy & De 1979).
DIKARYATIC AND HOMOKARYOTIC PAIRINGS: All pairings of dikaryotic isolates with the homokaryons of G.sepiarium(86126) resulted in the homokaryons being dikaryotised (by Buller phenomenon) after 3 weeks, thus proving the conspecificity of the paired isolates. The pairings were
G.sepiarium 86126 - i x G.sepiarium 87a +
- 4 x 105468 +
- 2 x 105468 +
- .3 x 105469 +
Taxon name: