The mating type of an ectomycorrhizal ammonia fungus, Hebeloma vinosophyllum, was tetrapolar. Four different mating types of the monokaryotic isolates, as well as the dikaryotic isolate, have fruiting ability. The patterns of basidioma formation of the dikaryotic and the monokaryotic isolates were categorized into three types. Type I standard fruiting was observed in the dikaryotic isolate whereas Type II and Type III fruitings were observed in monokaryotic isolates. Type II fruiting characterized by the irregular development of stipe and pileus and Type III fruiting categorized by the dwarf basidioma were observed by the isolates having different alleles in incompatible factor A (Type II: A^x B^x, A^xB^y and Type III: A^yB^x, A^yB^y), irrespective of different alleles in incompatible factor B. The dikaryotic basidioma produced more than 1×10^7 spores/pileus whereas the monokaryotic basidioma produced less than 1/40 the numbers of basidiospores produced on the dikaryotic basidioma. Percentage germination of basidiospores produced by the dikaryotic basidioma was higher than that of basidiospores produced by the monokaryotic basidiomata. The propagation strategy of H. vinosophyllum is discussed based on its ability of monokaryotic fruiting accompanying basidiospore germination.

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The anti-fungal activities of oxyresveratrol (2,4,3',5'-tetrahydroxystilbene) against the white-rot fungi Coriolus versicolor and Phellinus linteus, and the brown-rot fungus Fomitopsis palustris, were compared with those of phenol, polyphenols and resveratrol in relation to their structures. The results indicated that a hydroxyl group in the 2 position of oxyresveratrol seems to play a critical role in inhibiting mycelial growth of wood-rot fungi. The anti-fungal activity of oxyresveratrol could be the result of its effective disturbance of the cell wall structure of wood-rot fungi because of its greater hemolytic and albumin coagulation activities than those of other phenols. A callus-like cell aggregate was frequently found in the mycelia of C. versicolor and F. palustris incubated in a liquid culture with oxyresveratrol by electron microscopic observation. P. linteus seemed to be less sensitive to oxyresveratrol than C. versicolor and F. palustris.

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Cultural conditions that stimulate Agaricus blazei basidiospore germination were examined using four heterokaryotic strains. Spore germination rates on water agar medium were very low (below 0.5 %), and spores failed to germinate on potato-dextrose agar or glucose-malt-yeast agar media. Significantly higher spore germination was observed on agar medium containing hot water extracts of bark compost (BA medium), indicating that the extracts contain compounds that stimulate spore germination. The main materials that stimulate spore germination of A. blazei in the extracts are polar compounds of high molecular weight. Heat pre-treatment of spores at 30-50℃ was effective for increasing germination rates, particularly for 5-10 min at 50℃. Co-culturing with living mycelium of A. blazei stimulated spore germination. The optimum pH value of BA germination medium was 5, and the addition of oxalic and succinic acids stimulated spore germination. A combination of optimum conditions determined from individual experiments gave the highest values of germination rates, ranging from 3.1% to 4.8%.

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Laccase production by Strobilurus ohshimae and its use for decolorizing phenolic dyes were studied. S. ohshimae strain Nagaoka 1-1 was cultivated for 30 days on sugi wood meal medium (sugi wood meal : rice bran : water = 10:3:30). Laccase activity was 405U/g of medium (dry weight), which is higher than previously reported levels. Decolorization of 7 phenolic dyes was then tested using this enzyme, and all were decolorized. Cresol red was decolorized most, by more than 40% over 2 hours. The addition of 1-hydroxybenzotriazole (HOBt), which is redox mediator, increased rate of decolorization. With addition of HOBt, cresol red was decolorized completely in 40 min, and remazole brilliant blue R in 80 min.

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