title: QTLs for days to silking in a  recombinant inbred line maize population subjected to high and low nitrogen  regimes.
abstract: Days to  silking (DTS) is one of the most important traits in maize (Zea mays).  To investigate its genetic basis, a recombinant inbred line population was  subjected to high and low nitrogen (N) regimes to detect quantitative trait  loci (QTLs) associated with DTS. Three QTLs were identified under the high N  regime; these explained 25.4% of the phenotypic variance. Due to additive  effects, the QTL on chromosome 6 increased DTS up to 0.66 days; while the other  two QTLs mapped on chromosome 9 (one linked with Phi061 and the other linked  with Nc134) decreased DTS 0.89 and 0.91 days, respectively. Under low N regime,  two QTLs were mapped on chromosomes 6 and 9, which accounted for 25.9% of the  phenotypic variance. Owing to additive effects, the QTL on chromosome 6  increased DTS 0.67 days, while the other QTL on chromosome 9 decreased it 1.48  days. The QTL on chromosome 6, flanked by microsatellite markers Bnlg1600 and  Phi077, was detected under both N regimes. In conclusion, we identified four  QTLs, one on chromosome 6 and three on chromosome 9. These results contribute  to our understanding of the genetic basis of DTS and will be useful for  developing marker-assisted selection in maize breeding programs.
authors.affiliation: Nanchong Institute of Agricultural Sciences, Nanchong City, PR China.
authors.forename: Z P
authors.initials: ZP
authors.lastname: Zheng
authors.forename: X H
authors.initials: XH
authors.lastname: Liu
authors.forename: Y B
authors.initials: YB
authors.lastname: Huang
authors.forename: X
authors.initials: X
authors.lastname: Wu
authors.forename: C
authors.initials: C
authors.lastname: He
authors.forename: Z
authors.initials: Z
authors.lastname: Li
mesh_terms: D002874:Chromosome Mapping; D032461:Chromosomes, Plant; D009584:Nitrogen / Q000378:metabolism*; D040641:Quantitative Trait Loci; D003313:Zea mays / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism
chemical_list: D009584:Nitrogen