Agaricus blazei Murrill is cultivated with compost as a medium. The fermentation process of the compost was investigated by colony numbers of microorganisms （fungi, bacteria and actinomycetes）, PCR-DGGE analysis of bacterial flora, C/N ratio, and fresh yield of the fruit bodies using compost at each fermentation stage. The numbers of bacteria and actinomycetes peaked on 30 days, whereas the number of fungi was the highest at the beginning of fermentation. PCR-DGGE analysis revealed that bacterial flora was changing until day 30 and then became fixed. The C/N ratio decreased from 90 to 40-50 in 30 days and was constant thereafter. The yield of A. blazei Murrill fresh fruit bodies was less than 5 g/bin when composts fermented for 0-20 days were used, but over 26 g/bin with composts at fermented for 30-41 days. Therefore, compost in which bacterial flora and C/N ratio are stable appear to be an appropriate medium for A. blazei Murrill cultivation. These results suggest that we can use not only C/N ratio but also bacterial flora to evaluate the maturation of compost.

The community structure of ectomycorrhizal fungi associated with Abies firma was studied focusing on both aboveground fruit-bodies and belowground ectomycorrhizas with morphological and molecular methods. During 3 years of monitoring, 13 genera and 39 species of ectomycorrhizal fungi were found in a 10×30 m plot and Russula sp.1 fruitied most frequently and abundantly. Ectomycorrhizal roots of A. firma were distinguished based on the hyphal arrangement of fungal mantles and on PCR-RFLP analyses amplified the rDNA of the internal transcribed spacer （ITS） region. Abies firma ectomycorrhizas were divided into a total of 48 morphotypes, most of which showed unique RFLP types that indicated that each of these morphotypes was colonized by a single fungal species. The most frequent morphotype had an identical RFLP pattern with that of frutbodies of Russula sp.1. The relative frequency of fruit-bodies and morphotypes showed a geometric distribution pattern. These results indicate that there were a few dominant species, a few rare species, and many intermediately abundant species. In addition, the stress tolerance of ectomycorrhizal fungi to salinity and heavy metals was examined in vitro. The response of the fungi to NaCl varied among species and strains tested. Promising fungal strains for bioremediations can be obtained by mono- and dual-cultural experiments after understandings of mycorrhizal community structures in the field.

The original Japanese names of two Scleroderma species were traced and confirmed. Japanese names for these fungi currently used in Japanese icons and literature that cause misinterpretations are proposed to be replaced with the original names.

Three species of the genus Phallus, i.e. Phallus hadriani, P. rubicundus and P. rubrovolvatus were rediscovered from Japan. These species are described and illustrated based on their morphological characteristics.