title: A metabolomic study in oats (Avena sativa) highlights a drought tolerance mechanism based upon salicylate signalling pathways and the modulation of carbon, antioxidant and photo-oxidative metabolism.
abstract: Although a wealth of information is available on the induction of one or several drought-related responses in different species, little is known of how their timing, modulation and crucially integration influence drought tolerance. Based upon metabolomic changes in oat (Avena sativa L.), we have defined key processes involved in drought tolerance. During a time course of increasing water deficit, metabolites from leaf samples were profiled using direct infusion-electrospray mass spectroscopy (DI-ESI-MS) and high-performance liquid chromatography (HPLC) ESI-MS/MS and analysed using principal component analysis (PCA) and discriminant function analysis (DFA). The involvement of metabolite pathways was confirmed through targeted assays of key metabolites and physiological experiments. We demonstrate an early accumulation of salicylic acid (SA) influencing stomatal opening, photorespiration and antioxidant defences before any change in the relative water content. These changes are likely to maintain plant water status, with any photoinhibitory effect being counteracted by an efficient antioxidant capacity, thereby representing an integrated mechanism of drought tolerance in oats. We also discuss these changes in relation to those engaged at later points, consequence of the different water status in susceptible and resistant genotypes.
authors.affiliation: Institute for Sustainable Agriculture, CSIC, Apdo. 4084, Córdoba, 14080, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: Sánchez-Martín
authors.affiliation: Institute of Biological, Environmental and Rural Sciences, University of Aberystwyth, Aberystwyth, SY23 3DA, UK.
authors.forename: Jim
authors.initials: J
authors.lastname: Heald
authors.affiliation: Institute of Biological, Environmental and Rural Sciences, University of Aberystwyth, Aberystwyth, SY23 3DA, UK.
authors.forename: Alison
authors.initials: A
authors.lastname: Kingston-Smith
authors.affiliation: Institute of Biological, Environmental and Rural Sciences, University of Aberystwyth, Aberystwyth, SY23 3DA, UK.
authors.forename: Ana
authors.initials: A
authors.lastname: Winters
authors.affiliation: Institute for Sustainable Agriculture, CSIC, Apdo. 4084, Córdoba, 14080, Spain.
authors.forename: Diego
authors.initials: D
authors.lastname: Rubiales
authors.affiliation: Institute of General Organic Chemistry, CSIC, Juan de la Cierva 3, Madrid, 28006, Spain.
authors.forename: Mariluz
authors.initials: M
authors.lastname: Sanz
authors.affiliation: Institute of Biological, Environmental and Rural Sciences, University of Aberystwyth, Aberystwyth, SY23 3DA, UK.
authors.forename: Luis A J
authors.initials: LA
authors.lastname: Mur
authors.affiliation: Institute for Sustainable Agriculture, CSIC, Apdo. 4084, Córdoba, 14080, Spain.
authors.forename: Elena
authors.initials: E
authors.lastname: Prats
mesh_terms: D000975:Antioxidants / Q000378:metabolism*; D018554:Avena / Q000502:physiology* / Q000528:radiation effects; D002244:Carbon / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D019069:Cell Respiration; D002734:Chlorophyll / Q000378:metabolism; D055864:Droughts; D005978:Glutathione / Q000378:metabolism; D006038:Glyoxylates / Q000378:metabolism; D008027:Light; D055432:Metabolomics; D018515:Plant Leaves / Q000502:physiology / Q000528:radiation effects; D054046:Plant Stomata / Q000502:physiology / Q000528:radiation effects; D011392:Proline / Q000378:metabolism; D020156:Salicylic Acid / Q000378:metabolism; D015398:Signal Transduction; D014867:Water / Q000378:metabolism
chemical_list: D000975:Antioxidants; D006038:Glyoxylates; D014867:Water; D002734:Chlorophyll; D002244:Carbon; D011392:Proline; D005978:Glutathione; C031150:glyoxylic acid; D020156:Salicylic Acid
keywords: metabolomics; photorespiration; salicylic acid