African Journal of

  • Abbreviation: Afr. J. Biotechnol.
  • Language: English
  • ISSN: 1684-5315
  • DOI: 10.5897/AJB
  • Start Year: 2002
  • Published Articles: 12278

Full Length Research Paper

Identification of the quantitative trait loci for grain rate in maize

  Xiaohong Liu1, Sulan He2, Zuping Zheng2*, Zhenbo Tan3 and Daihui Liu2  
  1College of Life Sciences, China West Normal University, Nanchong City 637009, People’s Republic of China; Key Laboratory of Southwest China Wildlife Resources Conservation (Ministry of Education), People’s Republic of China. 2Nanchong Institute of Agricultural Sciences, Nanchong City 637000, People’s Republic of China. 3Beijing IPE Bio-technology Co., Ltd, Beijing City 100085, People’s Republic of China.
Email: [email protected]

  •  Accepted: 23 September 2010
  •  Published: 22 November 2010



Grain rate (GR) is a very important trait in maize (Zea mays L.) breeding program related to yield. To realize its genetic basis, a recombinant inbred line (RIL) population and different nitrogen (N) regimes were used to map the quantitative trait loci (QTLs) for GR in maize. As a result, two QTLs were identified under high N regime and could explain a total of 14.84% of phenotypic variance. Due to additive effect, the QTL on chromosome 6 could decrease 0.029 of GR, while the QTL on chromosome 9 could increase 0.0203 of GR. Under low N regime, one QTL was mapped on chromosome 6 and could account for 9.52% of phenotypic variance, and owning to additive effect, the QTL could make GR decrease by 0.0234. The result in comparison with previous studies showed that the three QTLs in this present study were new quantitative loci associated with GR in maize. These results were beneficial for understanding the genetic basis of GR in maize.


Key words: Maize (Zea mays L.), grain rate, quantitative trait locus, recombinant inbred line, nitrogen.


Abbreviations: GR, Grain rate; QTL, quantitative trait locus; RIL, recombinant inbred line; N, nitrogen; HNR, high nitrogen regime; LNR, low nitrogen regime; CIM, composite interval mapping; LOD, log10 of odds ratio.