大豆不同环境下脂肪酸组分含量的QTL分析

大豆油的品质取决于脂肪酸各组分在大豆中的比例, 为发掘控制大豆5种脂肪酸含量的数量性状位点(QTL), 利用冀豆12和黑豆重组自交系群体构建遗传图谱, 采用Windows QTL Cartographer 2.5和QTL Network-2.0软件的CIM和MCIM法对大豆5种脂肪酸组分进行数量性状定位。结果表明，在石家庄和三亚各环境下共检测到16个QTL, 位于连锁群A2、B2、C2、F、G、I、L上。对2个环境联合分析, 检测到13个QTL, 其中9个用2种方法被检测到, 但这13个位点与环境互作的贡献率明显小于加性效应。其中在B2连锁群Satt168~Satt556控制硬脂酸的QTL Ste-1在河北石家庄和海南三亚均能被检测到, 贡献率均为12%, 在双尾群体和间隔挑选群体中也能检测到控制硬脂酸的QTL Ste-1, 说明这一QTL稳定存在于本组合群体中, 为今后大豆硬脂酸的QTL精细定位奠定了基础。

Analysis of QTL for Fatty Acid Contents under Different Environments in Soybean

Soybean is an important crop which contributes about 60% of the world’s oilseed production. The quality of soybean oil depends on the relative composition of fatty acid in seeds. A population of recombinant inbred linesderived from a cross of Jidou 12 × Heidou was grown in two environments and the seed samples from the environments were evaluated for fatty acid contents. Simple sequence repeat (SSR) markers were used to construct genetic linkage map. A total of 16 QTLs underlying fatty acid contents were identified by CIM and MCIM methods using Windows QTL cartographer 2.5 and QTL Network-2.0 software at Sanya and Shijiazhuang locations, respectively. These QTLs were scattered on linkage groups A2, B2, C2, F, G, I, L. According to the two environment combined data, 13 QTLs were detected using two mapping methods. Nine of them were common in the results from two methods. Another QTL associated with stearic acid content, named as Ste-1, located on LG B2 and flanked by Satt168 and Satt556, was stable across two locations, also. QTL Ste-1 could explain 12% of the phenotypic variation at both locations. This study is helpful to improve fatty acid composition in soybean.