We discovered that Sarcoleotia globosa (Geoglossomycetes) fruited on the soil of ornamental Erica pot cultures, and its ascospores can germinate on plain agar. These findings prompted us to collect isolates from horticultural and natural environments in Japan and analyze their phylogeny and root colonizing ability. Pure cultures were successfully obtained from ascospores and surface-sterilized ericaceous roots. Phylogenetic analysis based on rRNA internal transcribed spacer sequences revealed that Japanese samples were separated into three strongly supported clades. Individual clade consisted of samples derived from (1) Erica pot cultures, (2) Rhododendron planted in a garden or Vaccinium pot culture, and (3) natural habitats in Hokkaido. Colony characteristics and in vitro root-colonizing morphology observed may correspond to these phylogenetic variations. Irrespective of the clades, all tested strains formed hyphal coils in vital rhizodermal cells of V. virgatum seedlings, which resembled those of ericoid mycorrhizae. Our results represent novel findings that can be the first step in unraveling the currently unknown ecology of geoglossoid fungi.

我们发现Sarcoleotia globosa (Geoglossomycetes) 在观赏埃里卡盆栽的土壤上结出果实，其子囊孢子可以在普通琼脂上发芽。这些发现促使我们从日本的园艺和自然环境中收集分离物，并分析它们的系统发育和根系定殖能力。从子囊孢子和表面灭菌的石蜡根中成功获得纯培养物。基于 rRNA 内部转录间隔序列的系统发育分析表明，日本样品被分成三个强烈支持的进化枝。单个进化枝由来自 (1) Erica盆栽培养物、(2)种植在花园或Vaccinium中的杜鹃花锅文化，以及（3）北海道的自然栖息地。观察到的菌落特征和体外根定殖形态可能与这些系统发育变异相对应。不考虑进化枝，所有测试的菌株都在V. virgatum幼苗的重要根皮细胞中形成菌丝卷曲，类似于石蜡菌根。我们的研究结果代表了新的发现，可能是解开目前未知的地舌真菌生态学的第一步。