Interaktion komplexierender und reduzierender Wurzelexudate in der Eisenakquisition
Abstract
Due to the low Fe solubility in most soils, plants have evolved Fe acquisition strategies that are mainly based on the chelation and reduction of ferric Fe. While graminaceous plants release mugineic acid-type siderophores for ferric Fe chelation, non-graminaceous plants rely primarily on the reduction of ferric Fe which is compromised at high pH. Recently, a new class of coumarin-type siderophores has been identified in root exudates that mediate ferric Fe chelation, however, due to their high chemical versatility their mode of action in the rhizosphere is still unclear. Therefore, the present project aims at i) identifying new exudate components with novel or specific Fe-related functions, in particular regarding the chelation and/or reduction of Fe(III) and to characterize modifications and chemical interactions of these components on their way from the release into the root apoplast to the soil and back; ii) examining synergisms among individual chemical processes involved in Fe mobilization from Fe-bearing phases in the soil; iii) identifying and quantifying the contribution and interplay of chemical and biological processes involved in Fe acquisition via plant-exuded reductants and ligands in the rhizosphere. To address a set of 8 sharply defined hypotheses, two German and two Austrian labs from molecular plant nutrition, analytical chemistry, rhizosphere ecology and biogeochemistry will collect root exudates from hydroponic and rhizosphere systems, conduct metal-chelate speciation by advanced MS-coupled techniques, assess Fe chelation and redox reactions of root exudates from wild-type and mutant plants and employ thermodynamic and kinetic modelling approaches. This proposal promises to chemically identify key players in root exudates and to describe their mode of action as chelators, reductants or redox shuttles for an improved Fe nutrition in plants.
Rhizosphäre Eisen Wurzelexsudate Mikronährstoffe Nährstoffverfügbarkeit
Publikationen
Mitarbeiter*innen
Markus Puschenreiter
Priv.-Doz. Dr. Markus Puschenreiter
markus.puschenreiter@boku.ac.at
Tel: +43 1 47654-91143, 91163
BOKU Projektleiter*in
01.09.2016 - 31.10.2020
BOKU Partner
Externe Partner
Leibniz-Institut für Analytische Wissenschaften
Weber, Günther, Dr.
Partner
Leibniz-Institut für Pflanzengenetik und Kulturpflanzenforschung
von Wirén, Nicolaus, Prof. Dr.
Partner
Universität Wien, Institut für Geologie
Prof. Stephan Krämer
Partner