无芥酸甘蓝型油菜十八碳不饱和脂肪酸含量的QTL定位

用无芥酸的高油酸油菜品系HOP和低油酸油菜品种湘油15为父母本构建含189单株的F₂代作图群体。F₂代单粒种子播种前采用半粒取样，F₂代单株种子采用混合取样，进行脂肪酸含量的气相色谱分析。统计检测显示这两种方法测定结果极显著相关，各种脂肪酸含量之间大部分也呈显著相关。用该群体构建含342个SSR标记的遗传连锁图并对18碳不饱和脂肪酸含量进行了QTL定位。在A5和C5连锁群上各检测到1个油酸含量主效QTL，其中位于A5连锁群的QTL效应值较大，且与FAD2基因紧密连锁；位于C5连锁群的QTL为首次报道，与之紧密连锁的标记在A5 连锁群QTL区域有同源标记，说明可能与位于C5的FAD2基因有关。用两种方法测定性状值都能检测到这2个QTL，且效应值比较接近，共能解释60%~70%油酸含量变异。由于油酸含量与亚油酸之间高度相关，定位在A5和C5的油酸含量QTL也被确认为亚油酸含量主效QTL，但利用单株法测定的性状值能在A4连锁群上再发现1个LOD值较低的亚油酸含量QTL。两种测定法能比较一致地在A4、A5和C4连锁群上检测到3个亚麻酸含量主效QTL，共能解释72%~80%亚麻酸含量变异。用半粒法能在A4连锁群还能检测到1个解释变异度为12.42%的较小LOD值的亚麻酸含量QTL。

QTL Analysis of 18-C Unsaturated Fatty Acid Contents in Zero-erucic Rapeseed(Brassica napus L.)

Rapeseed oil is a major edible oil source for human consumption. Its quality depends on its fatty acid composition. Among fatty acids, 18-C unsaturated fatty acids are most crucial. QTL mapping will pave a way for molecular breeding and cloning genes for fatty acid biosynthesis in rapeseed. In this study, the zero-erucic rapeseed parents HOP (high oleic) and Xiangyou 15 (low oleic) were used to construct a F2 population consisting of 189 individual plants. The construction of a genetic map containing 342 SS...