title: Association analysis of genomic loci important for grain weight control in elite common wheat varieties cultivated with variable water and fertiliser supply.
abstract: Grain weight, an essential yield component, is under strong genetic control and markedly influenced by the environment. Here, by genome-wide association analysis with a panel of 94 elite common wheat varieties, 37 loci were found significantly associated with thousand-grain weight (TGW) in one or more environments differing in water and fertiliser levels. Five loci were stably associated with TGW under all 12 environments examined. Their elite alleles had positive effects on TGW. Four, two, three, and two loci were consistently associated with TGW in the irrigated and fertilised (IF), rainfed (RF), reduced nitrogen (RN), and reduced phosphorus (RP) environments. The elite alleles of the IF-specific loci enhanced TGW under well-resourced conditions, whereas those of the RF-, RN-, or RP-specific loci conferred tolerance to the TGW decrease when irrigation, nitrogen, or phosphorus were reduced. Moreover, the elite alleles of the environment-independent and -specific loci often acted additively to enhance TGW. Four additional loci were found associated with TGW in specific locations, one of which was shown to contribute to the TGW difference between two experimental sites. Further analysis of 14 associated loci revealed that nine affected both grain length and width, whereas the remaining loci influenced either grain length or width, indicating that these loci control grain weight by regulating kernel size. Finally, the elite allele of Xpsp3152 frequently co-segregated with the larger grain haplotype of TaGW2-6A, suggesting probable genetic and functional linkages between Xpsp3152 and GW2 that are important for grain weight control in cereal plants. Our study provides new knowledge on TGW control in elite common wheat lines, which may aid the improvement of wheat grain weight trait in further research.
authors.affiliation: The State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China.
authors.forename: Kunpu
authors.initials: K
authors.lastname: Zhang
authors.forename: Junjun
authors.initials: J
authors.lastname: Wang
authors.forename: Liyi
authors.initials: L
authors.lastname: Zhang
authors.forename: Chaowu
authors.initials: C
authors.lastname: Rong
authors.forename: Fengwu
authors.initials: F
authors.lastname: Zhao
authors.forename: Tao
authors.initials: T
authors.lastname: Peng
authors.forename: Huimin
authors.initials: H
authors.lastname: Li
authors.forename: Dongmei
authors.initials: D
authors.lastname: Cheng
authors.forename: Xin
authors.initials: X
authors.lastname: Liu
authors.forename: Huanju
authors.initials: H
authors.lastname: Qin
authors.forename: Aimin
authors.initials: A
authors.lastname: Zhang
authors.forename: Yiping
authors.initials: Y
authors.lastname: Tong
authors.forename: Daowen
authors.initials: D
authors.lastname: Wang
mesh_terms: D000483:Alleles; D002874:Chromosome Mapping; D032461:Chromosomes, Plant; D003433:Crosses, Genetic; D002523:Edible Grain / Q000033:anatomy & histology / Q000235:genetics*; D004777:Environment; D005308:Fertilizers; D008040:Genetic Linkage; D055106:Genome-Wide Association Study; D006239:Haplotypes; D009584:Nitrogen / Q000172:deficiency; D010641:Phenotype; D010758:Phosphorus / Q000172:deficiency; D040641:Quantitative Trait Loci; D019655:Quantitative Trait, Heritable; D012639:Seeds / Q000033:anatomy & histology / Q000235:genetics*; D014908:Triticum / Q000033:anatomy & histology / Q000235:genetics*; D014867:Water / Q000494:pharmacology / Q000502:physiology*
chemical_list: D005308:Fertilizers; D014867:Water; D010758:Phosphorus; D009584:Nitrogen