Full Length Research Paper

Identification of the QTLs for grain yield using RIL population under different nitrogen regimes in maize

Xiao-Hong Liu¹, Su-Lan He², Zu-Ping Zheng²*, Yu-Bi Huang³, Zhen-Bo Tan⁴, Zhong Li², Chuan He², Xun Wu² and Quan-Bo Pu²

¹College of Life Sciences, China West Normal University, Nanchong City 637009, People’s Republic of China.

²Nanchong Institute of Agricultural Sciences, Nanchong City 637000, People’s Republic of China.

³Maize Research Institute, Sichuan Agricultural University, Ya’an City 625014, People’s Republic of China.

⁴Beijing IPE Bio-technology Company Limited, Beijing City 100085, People’s Republic of China.

*Corresponding author. E-mail: zzp0817@163.com. Tel: 86-13088139971.

Accepted 26 June, 2010

 Abstract

Quantitative trait locus (QTL) mapping can provide useful information for breeding programs, since it allows the estimation of genomic locations and genetic effects of chromosomal regions related to the expression of quantitative traits. To realize the genetic basis of grain yield of maize (Zea mays L.), a recombinant inbred line (RIL) population and two nitrogen (N) regimes were used to detect the QTLs for grain yield in maize, as a result, a total of six QTLs associated with grain yield per year (GYPE) were identified on chromosomes 1 (one), 6 (one), 8 (two) and 9 (two), with 0 - 12.0 cm of mapping interval between QTLs and their nearest markers. The three QTLs identified under high N regime could explain 18.07% of phenotypic variance, and could increase GYPE from 3.91 - 5.40 g, due to positive additive effects. Whereas, the three QTLs located under low N regime could account for 20.96% of phenotypic variance, and due to negative additive effects, they could decrease GYPE from 3.40 to 6.68 g. These results were beneficial for realizing the genetic basis of GYPE and developing marker-assisted selection in maize breeding project.

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