Population Structure of Typhula ishikariensis in Meadows and Pastures in Norway

Isolates of Typhula ishikariensis, a snow mould fungus, from Norway were divided into three groups, which, although differing in culture morphology and in mating reactions with testers of T. ishikariensis biotypes A and B from Japan, were, at least partially, interfertile. Population structures of this fungus at 23 sites in meadows and pastures were then determined, based on vegetative compatability group. Except for two sites dominated by a single large vegetative compatibility group, populations were generally diverse, regardless of the cropping history of the site.