title: Genome-Wide Linkage Mapping of QTL for Yield Components, Plant Height and Yield-Related Physiological Traits in the Chinese Wheat Cross Zhou 8425B/Chinese Spring.
abstract: Identification of genes for yield components, plant height (PH), and yield-related physiological traits and tightly linked molecular markers is of great importance in marker-assisted selection (MAS) in wheat breeding. In the present study, 246 F8 RILs derived from the cross of Zhou 8425B/Chinese Spring were genotyped using the high-density Illumina iSelect 90K single nucleotide polymorphism (SNP) assay. Field trials were conducted at Zhengzhou and Zhoukou of Henan Province, during the 2012-2013 and 2013-2014 cropping season under irrigated conditions, providing data for four environments. Analysis of variance (ANOVA) of agronomic and physiological traits revealed significant differences (P < 0.01) among RILs, environments, and RILs × environments interactions. Broad-sense heritabilities of all traits including thousand kernel weight (TKW), PH, spike length (SL), kernel number per spike (KNS), spike number/m(2) (SN), normalized difference in vegetation index at anthesis (NDVI-A) and at 10 days post-anthesis (NDVI-10), SPAD value of chlorophyll content at anthesis (Chl-A) and at 10 days post-anthesis (Chl-10) ranged between 0.65 and 0.94. A linkage map spanning 3609.4 cM was constructed using 5636 polymorphic SNP markers, with an average chromosome length of 171.9 cM and marker density of 0.64 cM/marker. A total of 866 SNP markers were newly mapped to the hexaploid wheat linkage map. Eighty-six QTL for yield components, PH, and yield-related physiological traits were detected on 18 chromosomes except 1D, 5D, and 6D, explaining 2.3-33.2% of the phenotypic variance. Ten stable QTL were identified across four environments, viz. QTKW.caas-6A.1, QTKW.caas-7AL, QKNS.caas-4AL, QSN.caas-1AL.1, QPH.caas-4BS.2, QPH.caas-4DS.1, QSL.caas-4AS, QSL.caas-4AL.1, QChl-A.caas-5AL, and QChl-10.caas-5BL. Meanwhile, 10 QTL-rich regions were found on chromosome 1BS, 2AL (2), 3AL, 4AL (2), 4BS, 4DS, 5BL, and 7AL exhibiting pleiotropic effects. These QTL or QTL clusters are tightly linked to SNP markers, with genetic distances to the closest SNPs ranging from 0 to 1.5 cM, and could serve as target regions for fine mapping, candidate gene discovery, and MAS in wheat breeding.
authors.affiliation: Key Laboratory of Soybean Biology, Soybean Research Institute, Ministry of Education, Northeast Agricultural UniversityHarbin, China; National Wheat Improvement Center, Institute of Crop Science, Chinese Academy of Agricultural SciencesBeijing, China; Keshan Sub-Academy, Heilongjiang Academy of Agricultural SciencesKeshan, China.
authors.forename: Fengmei
authors.initials: F
authors.lastname: Gao
authors.affiliation: National Wheat Improvement Center, Institute of Crop Science, Chinese Academy of Agricultural Sciences Beijing, China.
authors.forename: Weie
authors.initials: W
authors.lastname: Wen
authors.affiliation: National Wheat Improvement Center, Institute of Crop Science, Chinese Academy of Agricultural Sciences Beijing, China.
authors.forename: Jindong
authors.initials: J
authors.lastname: Liu
authors.affiliation: National Wheat Improvement Center, Institute of Crop Science, Chinese Academy of Agricultural SciencesBeijing, China; International Maize and Wheat Improvement Center (CIMMYT) China Office, c/o Chinese Academy of Agricultural SciencesBeijing, China.
authors.forename: Awais
authors.initials: A
authors.lastname: Rasheed
authors.affiliation: Zhoukou Academy of Agricultural Sciences Zhoukou, China.
authors.forename: Guihong
authors.initials: G
authors.lastname: Yin
authors.affiliation: National Wheat Improvement Center, Institute of Crop Science, Chinese Academy of Agricultural Sciences Beijing, China.
authors.forename: Xianchun
authors.initials: X
authors.lastname: Xia
authors.affiliation: Key Laboratory of Soybean Biology, Soybean Research Institute, Ministry of Education, Northeast Agricultural University Harbin, China.
authors.forename: Xiaoxia
authors.initials: X
authors.lastname: Wu
authors.affiliation: National Wheat Improvement Center, Institute of Crop Science, Chinese Academy of Agricultural SciencesBeijing, China; International Maize and Wheat Improvement Center (CIMMYT) China Office, c/o Chinese Academy of Agricultural SciencesBeijing, China.
authors.forename: Zhonghu
authors.initials: Z
authors.lastname: He
keywords: QTL; Triticum aestivum; linkage analysis; molecular marker; wheat 90K SNP array