Abstract:

【Objective】 QTL associated with grain size and related traits was identified and the phenotypic effects of them were estimated. The stability of QTL across different environments were detected. 【Method】 Using a set of 142 recombinant inbred lines (RILs) derived from Chinese winter wheat varieties Yu8679 and Heshangmai, five agronomic traits of grain length (GL), grain width (GW), grain thickness (GT), grain volume (GV) and 1000-grain weight (TGW) were evaluated in four different ecological environments of Beijing (2006 &2007), Hefei (2007) and Chengdu (2007), respectively. Based on 142 RILs, a genetic map comprising 170 SSR markers and two EST markers (Tx23-24 and Tx37-38) was generated. According to the genetic map and phenotypic data, quantitative trait loci (QTL) were located for these agronomic traits using the composite interval mapping method. 【Result】 A total of 93 QTL involving all wheat chromosomes except 1D and 6A were identified for these five traits over four environments. Among them, 17, 16, 18, 21 and 21 QTL for GL, GW, GT, GV and TGW were identified, respectively. In addition, 18 genomic regions with plenty of QTL were detected on 1A, 1B, 2A, 2D, 3A, 3B, 5A, 5B, 5D, 6A, 6D, 7B and 7D in this study. 【Conclusion】In the present study, 93 QTL for grain size and related traits were detected, which will provide useful information for molecular assistant selection (MAS) in wheat genetic improvement.

Key words: common wheat (Triticum aestivum L.), QTL, RILs, grain length, grain width, grain thickness, grain volume, thousand grain weight