Metabolite profiling of barley flag leaves under drought and combined heat and drought stress reveals metabolic QTLs for metabolites associated with antioxidant defense.
Barley (Hordeum vulgare L.) is among the most stress-tolerant crops; however, not much is known about the genetic and environmental control of metabolic adaptation of barley to abiotic stresses. We have subjected a genetically diverse set of 81 barley accessions, consisting of Mediterranean landrace genotypes and German elite breeding lines, to drought and combined heat and drought stress at anthesis. Our aim was to (i) investigate potential differences in morphological, physiological, and metabolic adaptation to the two stress scenarios between the Mediterranean and German barley genotypes and (ii) identify metabolic quantitative trait loci (mQTLs). To this end, we have genotyped the investigated barley lines with an Illumina iSelect 9K array and analyzed a set of 57 metabolites from the primary C and N as well as antioxidant metabolism in flag leaves under control and stress conditions. We found that drought-adapted genotypes attenuate leaf carbon metabolism much more strongly than elite lines during drought stress adaptation. Furthermore, we identified mQTLs for flag leaf γ-tocopherol, glutathione, and succinate content by association genetics that co-localize with genes encoding enzymes of the pathways producing these antioxidant metabolites. Our results provide the molecular basis for breeding barley cultivars with improved abiotic stress tolerance.
Julius Kühn-Institute, Federal Research Centre for Cultivated Plants, Institute of Resistance Research and Stress Tolerance, Erwin-Baur-Str. 27, D-06484 Quedlinburg, Germany.|Max Planck Institute for Breeding Research, Carl-von-Linné-Weg 10, D-50829 Köln, Germany.
Sven Eduard
SE
Templer
Friedrich-Alexander-Universität Erlangen-Nürnberg, Division of Biochemistry, Staudtstr. 5, D-91058 Erlangen, Germany.
Alexandra
A
Ammon
Friedrich-Alexander-Universität Erlangen-Nürnberg, Division of Biochemistry, Staudtstr. 5, D-91058 Erlangen, Germany.
David
D
Pscheidt
Friedrich-Alexander-Universität Erlangen-Nürnberg, Division of Biochemistry, Staudtstr. 5, D-91058 Erlangen, Germany.
Otilia
O
Ciobotea
Friedrich-Alexander-Universität Erlangen-Nürnberg, Division of Biochemistry, Staudtstr. 5, D-91058 Erlangen, Germany.
Christian
C
Schuy
Friedrich-Alexander-Universität Erlangen-Nürnberg, Division of Biochemistry, Staudtstr. 5, D-91058 Erlangen, Germany.
Christopher
C
McCollum
Friedrich-Alexander-Universität Erlangen-Nürnberg, Division of Biochemistry, Staudtstr. 5, D-91058 Erlangen, Germany.
Uwe
U
Sonnewald
Saatzucht Josef Breun GmbH & Co. KG, Amselweg 1, D-91074 Herzogenaurach, Germany.
Anja
A
Hanemann
SAATEN-UNION BIOTEC GmbH, Hovedisser Strasse 92, D-33818 Leopoldshöhe, Germany.
Jutta
J
Förster
Julius Kühn-Institute, Federal Research Centre for Cultivated Plants, Institute of Resistance Research and Stress Tolerance, Erwin-Baur-Str. 27, D-06484 Quedlinburg, Germany.
Frank
F
Ordon
Max Planck Institute for Breeding Research, Carl-von-Linné-Weg 10, D-50829 Köln, Germany.|Cluster of Excellence on Plant Sciences, Heinrich-Heine-Universität Düsseldorf, Institute for Plant Genetics, Universitätsstrasse 1, D-40225 Düsseldorf, Germany.
Maria
M
von Korff
Friedrich-Alexander-Universität Erlangen-Nürnberg, Division of Biochemistry, Staudtstr. 5, D-91058 Erlangen, Germany.
Lars Matthias
LM
Voll
D000222:Adaptation, Physiological; D055864:Droughts; D001467:Hordeum / Q000033:anatomy & histology* / Q000235:genetics / Q000502:physiology*; D006358:Hot Temperature / Q000009:adverse effects*; D018515:Plant Leaves / Q000033:anatomy & histology / Q000235:genetics / Q000502:physiology; D040641:Quantitative Trait Loci; D013312:Stress, Physiological
Barley; GABA shunt; combined heat and drought stress; genome-wide association mapping; glutathione; mQTL; metabolite profiling; thousand grain weight; tocopherol.