大豆亚麻酸含量的QTL分析

QTL ANALYSIS OF LINOLENIC ACID CONTENT IN SOYBEAN

由于亚麻酸的高度不饱和性,导致大豆油的稳定性和耐贮性降低,并严重影响豆奶的商品价值。因此降低大豆种子亚麻酸含量是当今大豆育种的一个重要目标。本研究利用正常亚麻酸含量的品种合丰25与亚麻酸含量仅为3%的突变品系L-14杂交所得的F2代和F3代群体,对500多对SSR引物进行筛选,共有90个SSR标记被分配到1999年Cregan定义的20条染色体中,QTL分析表明有3个分子标记Satt066、Satt424、Satt476与大豆亚麻酸含量密切相关,分别定位在连锁群MLG B2、MLG A2、MLG C1上,且变异贡献率分别为8.7%、4.99%和5.3%。并用这些分子标记对F3代家系进行了验证。

Linolenic acid is the unstable component of soybean oil that is responsible for a shortened shelf life of the oil and commercial value of soybean milk . Therefore, the breeding objective to reduce linolenic acid levels in soybean oil is very important. In the present study, F2 progeny segregating from a cross between Hefeng 25, a soybean cultivar with normal linolenic content, and L-14, a soybean mutant line with only 3% linolenic acid, were used to screen over 500 SSR markers. A total of 90 SSR markers were distributed in twenty linkage groups developed by Cregan et al. （1999）. QTL analysis showed that three SSR markers Satt066.Satt424 .Satt476 were relevant to low linolenic acid, whih were distributed in three linkage groups： MLG B2.MLG A2.MLG Cl,respectively. The three QTLs accounted for 8.7% .4. 99% and 5.3% of the phenotypic variation in linolenic acid level in this population, respectively. These markers have been tested on F3 generation.