Genet dynamics and ecological functions of the pioneer ectomycorrhizal fungi Laccaria amethystina and Laccaria laccata in a volcanic desert on Mount Fuji

To understand the reproduction of the pioneer ectomycorrhizal fungi Laccaria amethystina and Laccaria laccata in a volcanic desert on Mount Fuji, Japan, the in situ genet dynamics of sporocarps were analysed. Sporocarps of the two Laccaria species were sampled at fine and large scales for 3 and 2 consecutive years, respectively, and were genotyped using microsatellite markers. In the fine-scale analysis, we found many small genets, the majority of which appeared and disappeared annually. The high densities and annual renewal of Laccaria genets indicate frequent turnover by sexual reproduction via spores. In the large-scale analysis, we found positive spatial autocorrelations in the shortest distance class. An allele-clustering analysis also showed that several alleles were distributed in only a small, localised…