Morphological and cytological aspects of oidium formation in a basidiomycete, Pholiota nameko

Abstract

Pholiota nameko produced abundant oidia on aerial hyphae from monokaryotic and dikaryotic test stocks, but oidia were rare on submerged hyphae. The oidia from the former stocks had a layer of hydrophobic protein between the cell wall and the inner cell membrane, which was absent in the oidia from the latter. The only remarkable differences in the morphological features of the oidia from monokaryotic and dikaryotic mycelia was the slightly larger size of the latter. Observation of various test stocks on slide cultures revealed that about 80% of oidia were produced from the secondary branched hypha, and about 20% from the terminal hyphal cell of the main hypha. In the former, the secondary hyphae were segmented to form several oidium cells; in the latter, a single or several oidia were formed at the terminal end of the main hypha. Most oidia from monokaryons and dikaryons had only one haploid nucleus, while the remainders were multinucleate. Among the stocks tested, most oidia had a DNA content with a haploid amount at the G 1 phase of the cell cycle, but a few contained twice that amount corresponding to the G2 phase.

Dikaryotic arthroconidiation of Pleurotus subgenus Coremiopleurotus

“…They can also develop directly on the vegetative hyphae without the formation of conidiophores (Hui et al 1999). In contrast, Pleurotus subgenus Coremiopleurotus, which consists of subspecies members of Pleurotus cystidiosus O.K.…”