胡麻重组自交系脂肪酸含量的遗传分析

A Genetic Analysis of Fatty Acid Content in Recombinant Inbred Lines of Flax

以油用品种陇亚8号和纤用品种阿里安为亲本构建的含有162个家系的胡麻重组自交系(Recombinant inbred lines,RIL)为研究材料,利用气相色谱法测定了该RIL群体的脂肪酸含量,对其遗传变异与分布特征进行了分析,并应用主基因+多基因混合遗传模型,对粗脂肪和5种脂肪酸含量进行了初步遗传分析,旨在为该RIL群体后续研究利用提供参考。结果表明,RIL群体的粗脂肪与脂肪酸含量存在广泛变异,表现超亲分离现象,其分布近似为正态分布,呈现数量性状连续变异的典型分布特征;运用主基因+多基因遗传模型分析结果表明,粗脂肪含量为3对等加性主基因遗传,主基因遗传率为85%;5种脂肪酸组成中,亚麻酸含量为2对重叠作用主基因遗传,主基因遗传率为36%;亚油酸含量为3对等加性主基因遗传,主基因遗传率为80%;油酸、棕榈酸和硬脂酸含量均表现为无主基因效应的多基因遗传;同时筛选出高油高亚油酸、高亚麻酸优良品系材料11份,为胡麻品质育种提供了新的材料。

Using 162 families of a recombinant inbred line（RIL）population that crossed between oil-flax Longya8 and fiber-flax Alian, the fatty acid contents in the RIL population were measured by gas chromatography, and their genetic mutation and distribution traits were analyzed. Moreover, applying combined genetic model of major gene ＋ polygene, the contents of crude fat and 5 fatty acids were primarily analyzed in genetic aspect, aiming at providing the reference for further study of RIL population. The results showed that variations of contents of fatty acid and crude fat were significant, and the transgressive segregation of fatty acid content commonly existed. The frequency distributions of crude fat and fatty acid content in RIL populations showed the characteristics of approximately normal distribution and continuous variation of quantitative traits. The analysis by major gene ＋ polygene inheritance model revealed that the content of crude fat was controlled by three major genes with equal additive effects, and the heritability of major gene was 85%;among 5 fatty acids, the contents of linolenic acid was controlled by two major genes with duplicate effects, and the heritability of major gene was 36%;the content of linoleic acid was controlled by three major genes with equal additive effects, and the heritability of major gene was 80%;the contents of oleic acid, palmitic acid and stearic acid were controlled by polygene without major gene effects. Moreover, 11 fine RIL families with high oil and high linoleic acid content or high linolenic acid content were screened, which provides the new resources for flax quality breeding.