title: Fine mapping and candidate gene prediction of a pleiotropic quantitative trait locus for yield-related trait in Zea mays.
abstract: The yield of maize grain is a highly complex quantitative trait that is controlled by multiple quantitative trait loci (QTLs) with small effects, and is frequently influenced by multiple genetic and environmental factors. Thus, it is challenging to clone a QTL for grain yield in the maize genome. Previously, we identified a major QTL, qKNPR6, for kernel number per row (KNPR) across multiple environments, and developed two nearly isogenic lines, SL57-6 and Ye478, which differ only in the allelic constitution at the short segment harboring the QTL. Recently, qKNPR6 was re-evaluated in segregating populations derived from SL57-6×Ye478, and was narrowed down to a 2.8 cM interval, which explained 56.3% of the phenotypic variance of KNPR in 201 F(2∶3) families. The QTL simultaneously affected ear length, kernel weight and grain yield. Furthermore, a large F(2) population with more than 12,800 plants, 191 recombinant chromosomes and 10 overlapping recombinant lines placed qKNPR6 into a 0.91 cM interval corresponding to 198Kb of the B73 reference genome. In this region, six genes with expressed sequence tag (EST) evidence were annotated. The expression pattern and DNA diversity of the six genes were assayed in Ye478 and SL57-6. The possible candidate gene and the pathway involved in inflorescence development were discussed.
authors.affiliation: National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China ; College of Agronomy, Hebei Agricultural University, Baoding, China.
authors.forename: Ruixiang
authors.initials: R
authors.lastname: Liu
authors.forename: Haitao
authors.initials: H
authors.lastname: Jia
authors.forename: Xiaoliang
authors.initials: X
authors.lastname: Cao
authors.forename: Jun
authors.initials: J
authors.lastname: Huang
authors.forename: Feng
authors.initials: F
authors.lastname: Li
authors.forename: Yongsheng
authors.initials: Y
authors.lastname: Tao
authors.forename: Fazhan
authors.initials: F
authors.lastname: Qiu
authors.forename: Yonglian
authors.initials: Y
authors.lastname: Zheng
authors.forename: Zuxin
authors.initials: Z
authors.lastname: Zhang
mesh_terms: D000483:Alleles; D002874:Chromosome Mapping; D032461:Chromosomes, Plant / Q000235:genetics; D003433:Crosses, Genetic; D002523:Edible Grain / Q000235:genetics / Q000254:growth & development; D004843:Epistasis, Genetic; D020224:Expressed Sequence Tags; D056726:Genetic Association Studies; D058685:Genetic Pleiotropy; D018895:Microsatellite Repeats / Q000235:genetics; D010641:Phenotype; D040641:Quantitative Trait Loci / Q000235:genetics*; D003313:Zea mays / Q000235:genetics*