title: Genome-wide association mapping of agronomic and morphologic traits in highly structured populations of barley cultivars.
abstract: Genome-wide association study (GWAS) has become an obvious general approach for studying traits of agricultural importance in higher plants, especially crops. Here, we present a GWAS of 32 morphologic and 10 agronomic traits in a collection of 615 barley cultivars genotyped by genome-wide polymorphisms from a recently developed barley oligonucleotide pool assay. Strong population structure effect related to mixed sampling based on seasonal growth habit and ear row number is present in this barley collection. Comparison of seven statistical approaches in a genome-wide scan for significant associations with or without correction for confounding by population structure, revealed that in reducing false positive rates while maintaining statistical power, a mixed linear model solution outperforms genomic control, structured association, stepwise regression control and principal components adjustment. The present study reports significant associations for sixteen morphologic and nine agronomic traits and demonstrates the power and feasibility of applying GWAS to explore complex traits in highly structured plant samples.
authors.affiliation: School of Biosciences, The University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK.
authors.forename: Minghui
authors.initials: M
authors.lastname: Wang
authors.forename: Ning
authors.initials: N
authors.lastname: Jiang
authors.forename: Tianye
authors.initials: T
authors.lastname: Jia
authors.forename: Lindsey
authors.initials: L
authors.lastname: Leach
authors.forename: James
authors.initials: J
authors.lastname: Cockram
authors.forename: Jordi
authors.initials: J
authors.lastname: Comadran
authors.forename: Paul
authors.initials: P
authors.lastname: Shaw
authors.forename: Robbie
authors.initials: R
authors.lastname: Waugh
authors.forename: Luke
authors.initials: L
authors.lastname: Ramsay
authors.forename: Bill
authors.initials: B
authors.lastname: Thomas
authors.forename: Zewei
authors.initials: Z
authors.lastname: Luo
mesh_terms: D002874:Chromosome Mapping; D003198:Computer Simulation; D005819:Genetic Markers / Q000235:genetics; D005828:Genetics, Population; D055106:Genome-Wide Association Study; D005838:Genotype; D001467:Hordeum / Q000033:anatomy & histology* / Q000235:genetics* / Q000254:growth & development*; D016014:Linear Models; D010641:Phenotype; D020641:Polymorphism, Single Nucleotide / Q000235:genetics
chemical_list: D005819:Genetic Markers