title: Genome-metabolite associations revealed low heritability, high genetic complexity, and causal relations for leaf metabolites in winter wheat (Triticum aestivum).
abstract: We investigated associations between the metabolic phenotype, consisting of quantitative data of 76 metabolites from 135 contrasting winter wheat (Triticum aestivum) lines, and 17 372 single nucleotide polymorphism (SNP) markers. Metabolite profiles were generated from flag leaves of plants from three different environments, with average repeatabilities of 0.5-0.6. The average heritability of 0.25 was unaffected by the heading date. Correlations among metabolites reflected their functional grouping, highlighting the strict coordination of various routes of the citric acid cycle. Genome-wide association studies identified significant associations for six metabolic traits, namely oxalic acid, ornithine, L-arginine, pentose alcohol III, L-tyrosine, and a sugar oligomer (oligo II), with between one and 17 associated SNPs. Notable associations with genes regulating transcription or translation explained between 2.8% and 32.5% of the genotypic variance (pG). Further candidate genes comprised metabolite carriers (pG 32.5-38.1%), regulatory proteins (pG 0.3-11.1%), and metabolic enzymes (pG 2.5-32.5%). The combinatorial use of genomic and metabolic data to construct partially directed networks revealed causal inferences in the correlated metabolite traits and associated SNPs. The evaluated causal relationships will provide a basis for predicting the effects of genetic interferences on groups of correlated metabolic traits, and thus on specific metabolic phenotypes.
authors.affiliation: Department of Physiology and Cell Biology, Applied Biochemistry, Leibniz Institute of Plant Genetics and Crop Plant Research, Gatersleben, Germany.
authors.forename: Andrea
authors.initials: A
authors.lastname: Matros
authors.affiliation: Department of Breeding Research, Quantitative Genetics, Leibniz Institute of Plant Genetics and Crop Plant Research, Gatersleben, Germany.
authors.forename: Guozheng
authors.initials: G
authors.lastname: Liu
authors.affiliation: Department of Physiology and Cell Biology, Molecular Plant Nutrition, Leibniz Institute of Plant Genetics and Crop Plant Research, Gatersleben, Germany.
authors.forename: Anja
authors.initials: A
authors.lastname: Hartmann
authors.affiliation: Department of Breeding Research, Quantitative Genetics, Leibniz Institute of Plant Genetics and Crop Plant Research, Gatersleben, Germany.
authors.forename: Yong
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: Department of Breeding Research, Quantitative Genetics, Leibniz Institute of Plant Genetics and Crop Plant Research, Gatersleben, Germany.
authors.forename: Yusheng
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: Biometris, Department of Plant Sciences, Wageningen University, PB Wageningen, The Netherlands.
authors.forename: Huange
authors.initials: H
authors.lastname: Wang
authors.affiliation: KWS LOCHOW GmbH, Bergen, Germany.
authors.forename: Erhard
authors.initials: E
authors.lastname: Ebmeyer
authors.affiliation: KWS LOCHOW GmbH, Bergen, Germany.
authors.forename: Viktor
authors.initials: V
authors.lastname: Korzun
authors.affiliation: Nordsaat Saatzuchtgesellschaft mbH, Langenstein, Germany.
authors.forename: Ralf
authors.initials: R
authors.lastname: Schachschneider
authors.affiliation: Lantmännen SW Seed Hadmersleben GmbH, Hadmersleben, Germany.
authors.forename: Ebrahim
authors.initials: E
authors.lastname: Kazman
authors.affiliation: Limagrain GmbH, Peine-Rosenthal, Germany.
authors.forename: Johannes
authors.initials: J
authors.lastname: Schacht
authors.affiliation: University of Hohenheim, State Plant Breeding Institute, Stuttgart, Germany.
authors.forename: Friedrich
authors.initials: F
authors.lastname: Longin
authors.affiliation: Department of Breeding Research, Quantitative Genetics, Leibniz Institute of Plant Genetics and Crop Plant Research, Gatersleben, Germany.
authors.forename: Jochen Christoph
authors.initials: JC
authors.lastname: Reif
authors.affiliation: Department of Physiology and Cell Biology, Applied Biochemistry, Leibniz Institute of Plant Genetics and Crop Plant Research, Gatersleben, Germany.
authors.forename: Hans-Peter
authors.initials: HP
authors.lastname: Mock
mesh_terms: D018745:Genome, Plant; D055106:Genome-Wide Association Study; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism; D020641:Polymorphism, Single Nucleotide; D040641:Quantitative Trait Loci; D014908:Triticum / Q000235:genetics* / Q000378:metabolism
keywords: Genome-wide association; Triticum aestivum; mQTL; metabolomics; network analysis; winter wheat