title: Fast responses of metabolites in Vicia faba L. to moderate NaCl stress.
abstract: Salt stress impairs global agricultural crop production by reducing vegetative growth and yield. Despite this importance, a number of gaps exist in our knowledge about very early metabolic responses that ensue minutes after plants experience salt stress. Surprisingly, this early phase remains almost as a black box. Therefore, systematic studies focussing on very early plant physiological responses to salt stress (in this case NaCl) may enhance our understanding on strategies to develop crop plants with a better performance under saline conditions. In the present study, hydroponically grown Vicia faba L. plants were exposed to 90 min of NaCl stress, whereby every 15 min samples were taken for analyzing short-term physiologic responses. Gas chromatography-mass spectrometry-based metabolite profiles were analysed by calculating a principal component analysis followed by multiple contrast tests. Follow-up experiments were run to analyze downstream effects of the metabolic changes on the physiological level. The novelty of this study is the demonstration of complex stress-induced metabolic changes at the very beginning of a moderate salt stress in V. faba, information that are very scant for this early stage. This study reports for the first that the proline analogue trans-4-hydroxy-L-proline, known to inhibit cell elongation, was increasingly synthesized after NaCl-stress initiation. Leaf metabolites associated with the generation or scavenging of reactive oxygen species (ROS) were affected in leaves that showed a synchronized increase in ROS formation. A reduced glutamine synthetase activity indicated that disturbances in the nitrogen assimilation occur earlier than it was previously thought under salt stress.
authors.affiliation: Institute of Plant Nutrition and Soil Science, Christian Albrechts University Kiel, Hermann-Rodewald Str. 2, D-24118 Kiel, Germany. Electronic address: cmgeilfus@plantnutrition.uni-kiel.de.
authors.forename: Christoph-Martin
authors.initials: CM
authors.lastname: Geilfus
authors.affiliation: Department of Proteome and Metabolome Research, Faculty of Biology, Bielefeld University, Postfach 100131, D-33501 Bielefeld, Germany.
authors.forename: Karsten
authors.initials: K
authors.lastname: Niehaus
authors.affiliation: Department of Proteome and Metabolome Research, Faculty of Biology, Bielefeld University, Postfach 100131, D-33501 Bielefeld, Germany.
authors.forename: Victoria
authors.initials: V
authors.lastname: Gödde
authors.affiliation: Lehrfach Variationsstatistik, Christian Albrechts University Kiel, Hermann-Rodewald Str. 9, D-24118 Kiel, Germany.
authors.forename: Mario
authors.initials: M
authors.lastname: Hasler
authors.affiliation: Institute of Crop Science, Quality of Plant Products, University Hohenheim, Schloss, Westhof West, 118, D-70593 Stuttgart, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Zörb
authors.affiliation: Department of Proteome and Metabolome Research, Faculty of Biology, Bielefeld University, Postfach 100131, D-33501 Bielefeld, Germany.
authors.forename: Karin
authors.initials: K
authors.lastname: Gorzolka
authors.affiliation: Institute of Plant Nutrition and Soil Science, Christian Albrechts University Kiel, Hermann-Rodewald Str. 2, D-24118 Kiel, Germany.
authors.forename: Mareike
authors.initials: M
authors.lastname: Jezek
authors.affiliation: Institute of Applied Plant Nutrition, Plant Nutrition, Georg-August-University Göttingen, Carl-Sprengel-Weg 1, D-37075 Göttingen, Germany.
authors.forename: Mehmet
authors.initials: M
authors.lastname: Senbayram
authors.affiliation: Institute of Botany, Technische Universität Dresden, Zellescher Weg 20b, D-01062 Dresden, Germany.
authors.forename: Jutta
authors.initials: J
authors.lastname: Ludwig-Müller
authors.affiliation: Institute of Plant Nutrition and Soil Science, Christian Albrechts University Kiel, Hermann-Rodewald Str. 2, D-24118 Kiel, Germany.
authors.forename: Karl H
authors.initials: KH
authors.lastname: Mühling
mesh_terms: D008401:Gas Chromatography-Mass Spectrometry; D005973:Glutamine / Q000378:metabolism; D009584:Nitrogen / Q000378:metabolism*; D018515:Plant Leaves / Q000378:metabolism; D010940:Plant Proteins / Q000378:metabolism; D018517:Plant Roots / Q000378:metabolism; D011392:Proline / Q000031:analogs & derivatives / Q000096:biosynthesis*; D017382:Reactive Oxygen Species / Q000378:metabolism*; D055049:Salt Tolerance; D012965:Sodium Chloride / Q000378:metabolism*; D013312:Stress, Physiological; D031307:Vicia faba / Q000378:metabolism*
chemical_list: D010940:Plant Proteins; D017382:Reactive Oxygen Species; D005973:Glutamine; D012965:Sodium Chloride; D011392:Proline; D009584:Nitrogen
keywords: NaCl; OxyBURST Green H2HFF; Reactive oxygen species; Short-term salt stress; Spermidine; Vicia faba L.; trans-4-hydroxy-l-proline