title: Genetic loci mapping associated  with maize kernel number per ear based on a recombinant inbred line population  grown under different nitrogen regimes.
abstract: Kernel  number per ear (KNE) is one of the most important yield-related agronomic  traits in maize (Zea mays). To clarify its genetic basis, we made a  quantitative trait locus (QTL) analysis of KNE in a recombinant inbred line  population derived from lines Mo17 and Huangzao4, under two nitrogen (N)  regimes. Seven QTLs, on chromosomes 4, 6 and 9, were mapped under the high N  regime, which explained phenotypic variation ranging from 5.03 to 15.49%. Under  the low N regime, three QTLs were located on chromosomes 6 and 9, which  accounted for phenotypic variation ranging from 8.54 to 12.21%. These QTLs had  different mapping intervals to their nearest markers, ranging from 0 to 16.5  cM. According to the chromosome positions and genetic effects of these QTLs,  only seven QTLs for KNE were identified in our experiment, out of which three  were found under both N regimes, on chromosomes 6 (one) and 9 (two); the other  four were mapped only under the high N regime, on chromosomes 4 (three) and 6  (one). This information could be useful for developing marker-assisted  selection in maize-breeding projects.
authors.affiliation: Key Laboratory of Southwest China Wildlife Resources Conservation, Ministry of Education, College of Life Sciences, China West Normal University, Nanchong, PR China.
authors.forename: X H
authors.initials: XH
authors.lastname: Liu
authors.forename: S L
authors.initials: SL
authors.lastname: He
authors.forename: Z P
authors.initials: ZP
authors.lastname: Zheng
authors.forename: Z B
authors.initials: ZB
authors.lastname: Tan
authors.forename: Z
authors.initials: Z
authors.lastname: Li
authors.forename: C
authors.initials: C
authors.lastname: He
mesh_terms: D002874:Chromosome Mapping; D032461:Chromosomes, Plant; D003433:Crosses, Genetic; D008040:Genetic Linkage; D005819:Genetic Markers; D014644:Genetic Variation; D009584:Nitrogen; D010641:Phenotype; D030821:Plants, Genetically Modified / Q000235:genetics* / Q000254:growth & development; D040641:Quantitative Trait Loci; D012641:Selection, Genetic; D003313:Zea mays / Q000235:genetics* / Q000254:growth & development
chemical_list: D005819:Genetic Markers; D009584:Nitrogen