2026-05-20 理化学研究所
複雑な根圏試料を広域・高精細に観察する電子顕微鏡技術
＜関連情報＞
- https://www.riken.jp/press/2026/20260520_4/index.html
- https://www.nature.com/articles/s43247-026-03598-6
生物学的断面研磨走査型電子顕微鏡法により、植物－微生物－土壌界面の広範囲にわたる超微細構造マッピングが可能になる Biological cross-sectional polishing scanning electron microscopy enables wide-area ultrastructural mapping of intact plant–microbe–soil interfaces
Kiminori Toyooka,Yuko Saito,Satomi Kojima,Yumi Goto & Mayuko Sato
Communications Earth & Environment Published:13 May 2026
DOI:https://doi.org/10.1038/s43247-026-03598-6 Unedited version
Abstract
Ultrastructural observation of the rhizosphere requires preservation of spatial continuity across heterogeneous biological and mineral components. Although correlative imaging approaches integrate electron microscopy with chemical and isotopic analyses, maintaining large-area structural integrity in intact plant–microbe–soil composites remains technically demanding. Here, we show that biological cross-sectional polishing scanning electron microscopy enables centimeter-scale cross-sectional observation of resin-embedded soil interfaces while retaining subcellular ultrastructural detail. The workflow combines conventional fixation used for plant electron microscopy with low-viscosity resin embedding, diamond band-saw sectioning, and mechanical polishing to generate flat cross sections suitable for backscattered electron imaging using standard scanning electron microscopes. Application to laboratory-grown and field-collected samples revealed microbial aggregates, biofilm-like matrices, fungal networks, and diverse soil-associated organisms observed within preserved spatial relationships. Although this method does not provide chemical or lineage-specific identification, it establishes a reproducible structural framework that complements multiscale imaging and supports targeted downstream analyses in complex environmental systems.
