Novel methods for sampling and detection of root exudates
Abstract
Plant roots significantly influence the surrounding soil (i.e. rhizosphere) by exuding various organic compounds. This process called root exudation has a significant influence on soil chemistry, physics and biology and thus may largely determine the bioavailability of nutrients and toxic compounds. Previously, some research effort was put on the investigation of the root exudates, but in most cases only a small spectrum of the complete set of different compounds was investigated. Additionally, a majority of the exudates were obtained from hydroponic experiments, where the root exudate pattern may largely differ from a soil environment. The aim of this project is to implement high-end analytical techniques allowing the analysis of a large variety of target compound groups. Rhizobox systems will be implemented for the collection of exudates from soil-grown plants. This requires the adaptation of sampling devices in order to obtain unbiased sample concentrations at low volumes. Workpackage 1 will focus on (i) the development of a protocol for extracting low molecular weight organic compounds (LMWOC) from rhizosphere soil; (ii) improvement of micro suction cups to minimize bias of the target compound concentration in the sample; (iii) improvement of a recently developed exudate collector system using alternative materials to avoid target compound adsorption. Workpackage 2 will focus on the implementation of high-end analytical approaches to analyse a broad spectrum of target compounds. This will include the (i) implementation of miniaturized liquid chromatography systems with mass spectrometry detectors (LC-MS) for analysis of low sample volumes; (ii) design of online enrichment procedures; (iii) development, validation and application of a two-dimensional LC-MS system for simultaneous detection and quantification of the target compound groups. In Workpackage 3, a case study will be conduced to validate both the improved sampling methods as well as the application of the high-end analytical techniques. Additionally, the sampling techniques applied in the rhizobox system will be evaluated by comparison to aconventional hydroponic approach. The results of this project will be a major step to further understand the very complex processes in the rhizosphere of plants.
keywords root exudates rhizosphere HPLC-MS rhizobox
Publikationen
Project staff
Markus Puschenreiter
Priv.-Doz. Dr. Markus Puschenreiter
markus.puschenreiter@boku.ac.at
Tel: +43 1 47654-91143, 91163
Project Leader
01.11.2007 - 30.09.2009
Walter Wenzel
Univ.Prof. Dipl.-Ing. Dr.nat.techn. Walter Wenzel
walter.wenzel@boku.ac.at
Tel: +43 1 47654-91143, 91161
Project Staff
01.11.2007 - 30.09.2009
Stephan Hann
Univ.Prof. Dr. Stephan Hann
stephan.hann@boku.ac.at
Tel: +43 1 47654-77001, 77191
Sub Projectleader
01.11.2007 - 30.09.2009
Eva Oburger
Priv.-Doz. Dipl.-Ing. Dr. Eva Oburger
eva.oburger@boku.ac.at
Tel: +43 1 47654-91163
Project Staff
01.11.2007 - 30.09.2009