The biodiversity and species-area relationship of basidiomycetous macro fungi recorded on seven islands along the southwestern coast of the Kii-Peninsula were investigated from the viewpoint of the island biogeography. Some fungi such as Marasmiellus candidus, Crepidotus mollis, Russula castanopsidis, Microporus flabelliformis, Polyporus arcularius, Phellinus gilvus, and Auricularia polytricha were observed on four or more islands have in common. It should be noted that most of them are wood inhabiting saprophytes, except R. castanopsidis, which is an ectomycorrhiza former. The number of observed species on a given island was closely fitted to the natural vegetation area of the island by a conventional power function S=cA^2, where S is the number of species, A is the area, and c and z are constants. A deduced z value of 0.350 was relatively small in comparing with that of vascular plants but larger than that of animals that were assessed on other islands having similar geographical conditions with this study. There was no negative correlation between distance from the land community and the number of species. High similarities of the species composition between islands represented by Ochiai's index were exhibited between islands with similar sizes of area, islands locate close to the same land community, or islands distribute in clump.

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The nutritional requirements for the vegetative growth of Sparassis crispa Wulf.: Fr. were investigated with the use of a liquid culture medium. A wide range of carbohydrates served as a carbon source in the medium, which supported growth of S. crispa. Glucose, galactose, mannose, fructose, soluble starch, glycogen and dextrin were especially good carbon sources for mycelial growth. The optimal concentration of the carbon source was 2% in the case of glucose, and when it was more than 3%, the yield of mycelium decreased. The optimal concentration of the carbon source was 5% in case of soluble starch, and mycelium also grew in the concentration of 13%. Yeast extract, Soyton, polypeptone, meat extract and Casamino acid were acceptable nitrogen sources for the growth, while ammonium and nitrate salts were poor nitrogen sources. Alanine, valine, aspartic acid, glutamic acid, arginine, lysine and serine had the effect on the vegetative growth, but there was nothing to match with Casamino acid. The optimal concentration of the nitrogen source in the medium was 0.01-0.04%N.

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A wild mushroom food custom was investigated in the small town of Heguri, Nara Prefecture, southwestern Japan. Deciduous trees mixed with evergreen broadleaved trees dominate the slopes as a secondary forest, while bamboo stands and a Japanese red pine forest grow closely around the villages that make up the town. Here, more than 200 mushroom species grow in the stands and forests, of which only 9 are traditionally gathered and consumed. These nine species are limited to ectomycorrhiza-forming basidiomycetes associated with Japanese red pine as symbiotic partners. Other types of mushrooms found in the broad-leaved forest are not harvested, even though some are known as commercially cultivated fungi or are popularly used elsewhere, especially in northeastern Japan. This study revealed tight relationships among people, the red pine forest, and ectomycorrhizal fungi, forming a wild mushroom food custom typical to southwestern Japan.

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Changes in the distribution of low molecular weight carbohydrates, glycogen, and organic acids in the mycelia during the vegetative growth of Sparassis crispa wulf.: Fr. were studied. The organic acids accumulated in the culture medium were formic, acetic, oxalic, succinic, fumaric, malic, citric and isocitric acid, with the accumulation of oxalic acid more conspicuous than the other organic acids in particular. On a dry-weight basis, the low molecular weight carbohydrate content during vegetative growth was in the range of 9.5〜15.5% in the mycelia. Trehalose, glucose, fructose, arabitol and mannitol were identified in the mycelia, of which arabitol, mannitol and trehalose were the major components. On the same basis, the glycogen content was in the range of 7.0〜11.1 % in the mycelia. Trehalose, arabitol, mannitol and glycogen accumulated in the vegetative mycelia were thought to serve as carbohydrate reserves. The organic acid contents were in the range of 0.5〜1.2% in the mycelia, and nine organic acids were identified. Malic, citric, fumaric, oxalic and pyroglutamic acids were predominant in the mycelia.

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