• Mycobiology
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• v.32 no.4
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• pp.164-169
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• 2004

Development of oidia, a type of thallic spores from monokaryotic mycelium of Coprinus cinereus was examined with electron microscope and light microscopes. Oidia formation in this fungus is unique in its mode of formation compared with other types of asexual sporogenesis. Oidiogenesis in C. cinereus is carried out in three steps: 1) Formation of oidiophore from the parent mycelium, 2) Formation of initials of oidial cells from swollen oidiophore, 3) Segmentation and detachment of mature oidial cell. Oidiophores appear to spring out singly as a swollen hyphal branches from the normal foot hyphae or sometimes coiled hypha. From the oidiophore, oidial branches sprout out forming a group of $2{\sim}6$, most often 4 oidial cells and each oidial cell undergoes a single mitosis resulting in 2 oidia. One of the sibling oidial cells in a group is frequently transformed into a new oidiophore, thus oidiogenic structures are tandemly produced at the several different levels.

• Journal of Microbiology
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• v.37 no.1
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• pp.27-34
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• 1999

Two fractions with unusual antifungal activity that suppress asexual sporulation of several fungi were obtained from culture filtrate of Pseudomonas aeruginosa and were partially purified through the repeated silicagel flash column chromatographies. The sporulation-suppressive actions of these fractions in Aspergillus nidulans, Rhizopus stolonifer, and Coprinus cinereus, were analyzed by light and electron microscopes. The germination ability of the spores produced in the presence of these fractions were also checked to determine the persistent effects of these antifungal substances on the next generation. Light microscopic observation of developing sporangia of R. stolonifer grown in the presence of both fractions revealed that the significant number of sporangia failed to reach maturity, and frequently, uncontrolled growths of hyphae and rhizoids from the sporangiophores were found. In A. nidulans addition of these fractions appeared to cause different classes of morphological abnormality in conidia development, which included aborted formation of conidiogenous cells from the apex of conidiophores and enhanced hyphal growths either at the tip or middle of the conidiophores. Germination abilities of spores obtained from the cultures grown in the presence of antifungal fractions were 40∼60% in Aspergillus, 50∼80% in Coprinus (thallic spores), and 30∼40% in Rhizopus compared to those of normal spores.