title: Genetic dissection of the maize kernel development process via conditional QTL mapping for three developing kernel-related traits in an immortalized F2 population.
abstract: Kernel development is an important dynamic trait that determines the final grain yield in maize. To dissect the genetic basis of maize kernel development process, a conditional quantitative trait locus (QTL) analysis was conducted using an immortalized F2 (IF2) population comprising 243 single crosses at two locations over 2 years. Volume (KV) and density (KD) of dried developing kernels, together with kernel weight (KW) at different developmental stages, were used to describe dynamic changes during kernel development. Phenotypic analysis revealed that final KW and KD were determined at DAP22 and KV at DAP29. Unconditional QTL mapping for KW, KV and KD uncovered 97 QTLs at different kernel development stages, of which qKW6b, qKW7a, qKW7b, qKW10b, qKW10c, qKV10a, qKV10b and qKV7 were identified under multiple kernel developmental stages and environments. Among the 26 QTLs detected by conditional QTL mapping, conqKW7a, conqKV7a, conqKV10a, conqKD2, conqKD7 and conqKD8a were conserved between the two mapping methodologies. Furthermore, most of these QTLs were consistent with QTLs and genes for kernel development/grain filling reported in previous studies. These QTLs probably contain major genes associated with the kernel development process, and can be used to improve grain yield and quality through marker-assisted selection.
authors.affiliation: State Key Laboratory of Wheat and Maize Crop Science/Collaborative Innovation Center of Henan Grain Crops, Department of Agronomy, Henan Agricultural University, 95 Wenhua Road, Zhengzhou, 450002, China.
authors.forename: Zhanhui
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Wheat and Maize Crop Science/Collaborative Innovation Center of Henan Grain Crops, Department of Agronomy, Henan Agricultural University, 95 Wenhua Road, Zhengzhou, 450002, China.
authors.forename: Xiangyuan
authors.initials: X
authors.lastname: Wu
authors.affiliation: State Key Laboratory of Wheat and Maize Crop Science/Collaborative Innovation Center of Henan Grain Crops, Department of Agronomy, Henan Agricultural University, 95 Wenhua Road, Zhengzhou, 450002, China.
authors.forename: Chaonan
authors.initials: C
authors.lastname: Shi
authors.affiliation: State Key Laboratory of Wheat and Maize Crop Science/Collaborative Innovation Center of Henan Grain Crops, Department of Agronomy, Henan Agricultural University, 95 Wenhua Road, Zhengzhou, 450002, China.
authors.forename: Rongna
authors.initials: R
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Wheat and Maize Crop Science/Collaborative Innovation Center of Henan Grain Crops, Department of Agronomy, Henan Agricultural University, 95 Wenhua Road, Zhengzhou, 450002, China.
authors.forename: Shengfei
authors.initials: S
authors.lastname: Li
authors.affiliation: State Key Laboratory of Wheat and Maize Crop Science/Collaborative Innovation Center of Henan Grain Crops, Department of Agronomy, Henan Agricultural University, 95 Wenhua Road, Zhengzhou, 450002, China.
authors.forename: Zhaohui
authors.initials: Z
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Wheat and Maize Crop Science/Collaborative Innovation Center of Henan Grain Crops, Department of Agronomy, Henan Agricultural University, 95 Wenhua Road, Zhengzhou, 450002, China.
authors.forename: Zonghua
authors.initials: Z
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Wheat and Maize Crop Science/Collaborative Innovation Center of Henan Grain Crops, Department of Agronomy, Henan Agricultural University, 95 Wenhua Road, Zhengzhou, 450002, China.
authors.forename: Yadong
authors.initials: Y
authors.lastname: Xue
authors.affiliation: State Key Laboratory of Wheat and Maize Crop Science/Collaborative Innovation Center of Henan Grain Crops, Department of Agronomy, Henan Agricultural University, 95 Wenhua Road, Zhengzhou, 450002, China. gtang1@mtu.edu.|Department of Biological Sciences, Michigan Technological University, Houghton, MI, 49931, USA. gtang1@mtu.edu.
authors.forename: Guiliang
authors.initials: G
authors.lastname: Tang
authors.affiliation: State Key Laboratory of Wheat and Maize Crop Science/Collaborative Innovation Center of Henan Grain Crops, Department of Agronomy, Henan Agricultural University, 95 Wenhua Road, Zhengzhou, 450002, China. tangjihua1@163.com.
authors.forename: Jihua
authors.initials: J
authors.lastname: Tang
mesh_terms: D002874:Chromosome Mapping / Q000379:methods; D032461:Chromosomes, Plant / Q000235:genetics; D002523:Edible Grain / Q000235:genetics*; D004777:Environment; D005838:Genotype; D040641:Quantitative Trait Loci / Q000235:genetics*; D012639:Seeds / Q000235:genetics; D003313:Zea mays / Q000235:genetics*
keywords: Kernel density; Kernel development; Kernel volume; Kernel weight; Maize (Zea mays L.); QTL mapping