Schultes Sina R, Rüger Lioba, Niedeggen Daniela, Freudenthal Jule, Frindte Katharina, Becker Maximilian F, Metzner Ralf, Pflugfelder Daniel, Chlubek Antonia, Hinz Carsten, van Dusschoten Dagmar, Bauke Sara L, Bonkowski Michael, Watt Michelle, Koller Robert, Knief Claudia
Institute for Crop Science and Resource Conservation (INRES), Molecular Biology of the Rhizosphere, University of Bonn, Bonn, Germany.
Institute of Zoology, Terrestrial Ecology, Cluster of Excellence on Plant Sciences (CEPLAS), University of Cologne, Cologne, Germany.
Nat Commun. 2025 Aug 7;16(1):7286. doi: 10.1038/s41467-025-62550-y.
The spatial variation and underlying mechanisms of pattern formation in the rhizosphere microbiome are not well understood. We demonstrate that specific patterns in the distribution of recently fixed carbon within the plant root system influence the spatial organization of the rhizosphere microbiota. Non-invasive analysis of carbon allocation in the maize root system by C tracer-based positron emission tomography combined with magnetic resonance imaging reveals high spatial heterogeneity with highest C-signal accumulations at root tips and differences between root types. Strong correlations exist between root internal carbon allocation and rhizodeposition as evident from CO labeling. These patterns are reflected in the bacterial, fungal and protistan community structure in rhizosphere soil with differences depending on root structure and related spatial heterogeneities in carbon allocation. Especially the active consumers of C-labeled rhizodeposits are responsive to photosynthate distribution with differences in C-labeling according to their spatial localization within the root system. Thus, root photosynthate allocation supports distinct habitats in the plant root system and is a key determinant of microbial food web development, evident from C-labeling of diverse bacterial and protistan predators, especially at root bases, resulting in characteristic spatiotemporal patterns in the rhizosphere microbiome.
根际微生物群落中模式形成的空间变异及其潜在机制尚未得到充分理解。我们证明，植物根系内近期固定碳分布的特定模式会影响根际微生物群的空间组织。通过基于碳示踪剂的正电子发射断层扫描与磁共振成像相结合对玉米根系中的碳分配进行非侵入性分析，揭示了高度的空间异质性，根尖处的碳信号积累最高，且不同根类型之间存在差异。从一氧化碳标记可以明显看出，根内部的碳分配与根际沉积之间存在很强的相关性。这些模式反映在根际土壤中的细菌、真菌和原生生物群落结构中，其差异取决于根结构以及碳分配中相关的空间异质性。特别是被碳标记的根际沉积物的活跃消费者对光合产物分布有反应，根据它们在根系内的空间定位，碳标记存在差异。因此，根光合产物分配支持植物根系内不同的生境，并且是微生物食物网发育的关键决定因素，这从不同细菌和原生生物捕食者的碳标记中可以明显看出，尤其是在根基部，从而在根际微生物群落中形成特征性的时空模式。
