Abstract
Colonies of Tricholoma matsutake, which consist of fairy rings and the area they enclose, are called shiros in Japanese. We recently identified the antimicrobial substance at the active mycorrhizal zone, the shiro front, of T. matsutake as the (oxalato)aluminate complex. In the present study, seasonal changes in the content of the complex, the mycelial density of T. matsutake, antimicrobial activity, and pH were analyzed in the shiro area. Bacteria were isolated from the shiro area in October and identified, and their sensitivity to the complex was also examined. The change in the content of the complex approximately correlated with that of the mycelial density, and closely correlated with antimicrobial activity and pH. The bacteria from the shiro front were resistant to the complex, while some bacteria sensitive to the complex were found inside and outside the shiro front. This suggested that the complex expels sensitive bacteria from the shiro front along with the outward extension of the shiro, contributing to the protection and development of the shiro.
