Project Details
Projekt
Bridging biochemical gradients to elucidate key processes governing root -microbiome-soil interactions
Applicant
Privatdozent Dr. Hans Hermann Richnow
Subject Area
Soil Sciences
Ecology of Land Use
Plant Cultivation, Plant Nutrition, Agricultural Technology
Ecology of Land Use
Plant Cultivation, Plant Nutrition, Agricultural Technology
Term
from 2018 to 2023
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 403641683
Structure, function, and activity of the rhizosphere microbiome, with respect to its interactions with roots as well as with the non-living soil matrix are not well understood. This project aims to analyze structural and biochemical interactions of the soil microbiome comprising fungal and prokaryotic components with plant roots and non-living organic and mineral constituents of soil. Bridging scales (from nm to cm) by novel combinatory high spatial and mass resolution techniques we propose to identify key factors governing the self-organization and resilience of the rhizosphere. We hypothesize that the flux of carbon and nutrients (B, P, N, metals) to plants and the provision of root exudates and mucilage as a source of carbon and energy for the soil microbiome are the main factors governing the spatial organization of the rhizosphere. By analyzing the spatial variability of N, P and nutrients at scales down to the nm-range representing the habitat of a single cell in a biofilm interacting with the soil matrix or the surface of roots we will provide visual and quantitative information on concentration patterns in the rhizosphere that serve as an indicator of microbial driven processes.Resolving biogeochemical interactions of plant –microbiome–soil components and identifying their role in self-organization and resilience across various scales, we hope to provide a complete view on the function of the rhizosphere. We will combine complementary techniques for visualization of elemental and isotopic gradients with high spatial and mass resolution such as Laser-Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS), Time-of-Flight Secondary Ion Mass Spectrometry (ToFSIMS), Nano-scale-Secondary Ion Mass Spectrometry (NanoSIMS) and Helium Ion Microscopy (HIM), to visualize and quantify concentration patterns within the rhizosphere. N, P, C and micronutrients will be measured with spatial resolution of the soil texture with pores and roots (25 µm to cm) by LA-IPC-MS. Higher spatial resolution will be obtained by ToFSIMS (>150 nm) and electron microscopy (EM) (>10nm). Molecular ion spectroscopy by ToFSIMS will provide structural information of humic substances, mucilage, root exudates, lipids and biomarkers in the vicinity of roots. In conjunction with fluorescence in-situ hybridization NanoSIMS (>50 nm resolution) will be used to visualize elementary and isotope composition of soil aggregates and roots, to link identity to metabolic function of microorganisms and to quantify the flux of carbon and nutrients between roots and associated microbiome. HIM will provide micrographs of microbial surfaces, interfaces between roots, microbes and soil, secondary mineral phases and mucilage with unique resolution (>nm). This distinctive combinatory approach will bridge various scales and provide a holistic view on self-organization, functionality and resilience in soils. The obtained data will be provided for partners modelling soil microbial processes
DFG Programme
Priority Programmes
