Tricholoma matsutake forms a symbiotic association with coniferous trees, developing mycelial aggregations, called ‘shiro’, which are characterized by distinct chemical and physical properties from nearby forest bulk soil. The fungal diversity living in shiro soil play key roles in nutrient cycles for this economically important mushroom, but have not been profiled across large spatial and environmental gradients. Samples of shiro and non-shiro (nearby bulk soil) were taken from five field sites where sporocarps naturally formed. Phospholipid fatty acids (PLFA) and Illumina MiSeq sequencing were combined to identify fungal biomass and community structure. Matsutake dominated in the shiro, which had a significantly reduced saprotrophic fungi biomass compared to non-shiro soil. Fungal diversity was negatively correlated with the relative abundance of T. matsutake in the shiro soil. The fungal community in the shiro was characterized by similar fungal species composition in most samples regardless of forest types. Matsutake coexisted with a specific fungal community due to competition or nutrient interactions. Oidiodendron was positively correlated with the abundance of T. matsutake, commonly cohabitant in the shiro. In contrast, Helotiales and Mortierella were negatively correlated with T. matsutake, both of which commonly inhabit the non-shiro soil but do not occur in shiro soils. We conclude that T. matsutake generate a dominance effect to shape the fungal community and diversity in shiro soil across distinctive forest types.

Premise of the StudyNovel and cost‐effective microsatellite markers were developed to explore the population genetics, biogeographic structure, and evolutionary history of the prized Euro‐Asian wild edible ectomycorrhizal fungus Tricholoma matsutake (Tricholomataceae).Methods and resultsEighteen new polymorphic simple sequence repeat loci, detected from a microsatellite‐enriched genomic library, were used to characterize 131 individuals from eight T. matsutake populations. The number of alleles ranged from two to 10, with averages of 1.42 to 3.22. Levels of observed and expected heterozygosity ranged from 0.00–1.00 and from 0.00–0.83, with mean values of 0.21 and 0.26, respectively. In total, 50% of the loci showed interspecific transferability and polymorphism in the related species T. equestre.ConclusionsThese newly developed markers will aid research into the genetic diversity and population structure of T. matsutake. They can also be used in other species of Tricholoma.