%0 Journal Article
%A Lippold, Eva
%A Landl, Magdalena
%A Braatz, Eric
%A Schlüter, Steffen
%A Kilian, Rüdiger
%A Mikutta, Robert
%A Schnepf, Andrea
%A Vetterlein, Doris
%T Linking micro‐X‐ray fluorescence spectroscopy and X‐ray computed tomography with model simulation explains differences in nutrient gradients around roots of different types and ages
%J The new phytologist
%V 246
%N 4
%@ 0028-646X
%C Oxford [u.a.]
%I Wiley-Blackwell
%M FZJ-2025-05257
%P 1780 - 1795
%D 2025
%Z .This project was carried out in the framework of the priorityprogramme 2089 ‘Rhizosphere spatiotemporal organisation – akey to rhizosphere functions’ funded by Deutsche Forschungsgemeinschaft(DFG), German Research Foundation (projectnos.: 403641034, 403801423 and 403640293). The μ-XRFinstrument was also funded by the DFG (grant no.:344418428). The authors gratefully acknowledge SebastianRGA Blaser for help with X-ray CT measurements and analysis,Bernd Apelt for help in the laboratory whenever it wasneeded, Maxime Phalempin for help with the root segmentationalgorithm, Josefine Karte (Department Analytical Chemistry,Helmholtz Centre for Environmental Research – UFZ) forthe measurements of elemental contents in the soil solutions,Lisa Hofmann for the measurement of root diameters on completeroot systems and Gertraud Harrington for help with samplepreparation of the thin sections. Open Access fundingenabled and organized by Projekt DEAL.
%X Plant roots create chemical gradients within the rhizosphere, but little information exists onthe effect of root properties on the distribution of chemical gradients. The research aim was toanalyse and model the effects of root type and age, radial root geometry and root hairs onnutrient gradients in the rhizosphere. Using micro-X-ray fluorescence spectroscopy (μ-XRF) combined with X-ray computedtomography (X-ray CT), we analysed nutrient gradients around root segments with differentdiameters and ages of two Zea mays genotypes (wild-type and root hair defective mutant)growing in two substrates (loam and sand). Gradients of key nutrients were compared withgradients obtained by a process-based, radially symmetric 1D rhizosphere model. Results show that root hairs matter for nutrient uptake during supply limitation (phosphorus(P)), but not when it is limited by uptake kinetics (calcium (Ca), sulphur (S)). Higher Ca and Saccumulation was observed at the surface of older and thicker root segments than at youngerand thinner root segments. Micro-XRF proved suitable for the detection of nutrient gradients of Ca and S, but not of P.While continuum modelling was well suited to explain observed nutrient gradients, it was lesseffective in representing pore-related phenomena, such as precipitation reactions, which callsfor new homogenization approaches.
%F PUB:(DE-HGF)16
%9 Journal Article
%R 10.1111/nph.70102
%U https://juser.fz-juelich.de/record/1049174