航天诱变高油酸甘蓝型油菜突变体分子标记的筛选

Molecular Maker Screen for High Oleic Acid in Space Flight Mutant Brassica napus

【目的】利用与候选基因FAD2紧密连锁的SSR标记对航天诱变的高油酸F2群体进行SSR标记分析,筛选与该高油酸性状紧密连锁的SSR标记及分析其突变位点。【方法】F2群体母本10L421为黄籽低油酸高亚麻酸自交系,父本10L422为航天诱变的高油酸低亚麻酸的突变株自交系后代。对4条染色体(A05、A01、C05及C01)上的候选基因FAD2上下游100 kb区域设计的148对SSR引物在两亲本、高低油酸混合池及F2群体中进行分析。亲本及群体油酸含量采用气相色谱分析,根据分子标记结果对F2群体油酸含量进行单标记分析。【结果】有36对引物在亲本间表现多态性,多态频率为24%。其中10对SSR引物在2个亲本和高油酸、低油酸极端群体间均具有相同的多态性。显著性检验和单标记分析表明,A05和A01上与FAD2共分离的SSR标记在0.01显著水平上与油酸性状相关,单标记分析分别解释表型变异31.1%和29.4%。【结论】A05和A01染色体上的FAD2是控制该突变体材料高油酸性状变异的主效位点,且该高油酸突变体是由于A05和A01上FAD2的双隐性突变所致。

[Objective] A study was conducted to analyze the mutant locus and screen SSR markers tightly linked to high oleic acid in the high oleic acid space flight mutant derived F2 population by using the SSR markers beside FAD2 gene. [Method] The F2 population was derived from the cross of yellow seeded low oleic acid/high linolenic acid self line 10L421 and space flight mutant high oleic acid/low linolenic acid self line 10L422. Totally, 148 SSR markers beside FAD2 genes by 100 kb region in both sides from chromosomes A05, A01, C05 and C01 were analyzed in the two parents, high and low oleic acid bulks and F2 population. The parents and F2 plants oleic acid were analyzed by GC. Marker and oleic acid relationship were analyzed by single marker test. [Result] There were 36 of the SSR markers were polymorphic among the two parents, ten SSR markers showed a cosegregation in the high and low oleic acid extreme plants. The SSR markers beside FAD2 gene in A05 and A01 were significantly related to the oleic acid and accounted for 31.1% and 29.4% of the oleic acid variation by single marker analysis. [ Conclusion ] The ANOVA and single marker analysis indicated that the FAD2 genes in A05 and A01 are the major loci responsible for the oleic acid variation in this space flight mutant derived population, which means that the double recessive mutation of E4D2 genes in A05 and A01 lead to the high oleic acid content of the space flight mutant.