Abstract: Soybean is an important crops in the world due to its high seed protein and oil contents, while the contents of seed protein and oil attributed to the quantitative traits which were controlled by multiple minor-genes. Though there were many related QTLs reported, most of them only focused on the single additive QTLs, and few of them payed attentions to the epistatic QTLs. In this paper, a soybean RIL population (ZL) was used to study the epistatic QTLs of seed protein and oil contents by analyzing ZL population using Illumina BARCSoySNP6K Beadchip and detecting the phenotypes under four different environments. The results showed that there were 48 pairs of epistatic QTLs associated with protein content and 55 pairs of epistatic QTLs related to oil content in soybean seeds. Furthermore, there were 19 pairs of co-located epistatic QTLs controlling the protein and oil contents simultaneously. Among these co-located epistatic QTLs, 12 pairs of them shared the same QTL mapping regions, 2 pairs of them shared one same marker and five pairs of them had the QTLs regions not above 5 cM genetic distance, which could be regarded as the same QTL. Meanwhile, the results also showed that these epistatic QTLs located on nineteen chromosomes of soybean except for the chromosome 11. Thus, this study identified many epistatic QTLs for soybean seed protein and oil contents, which not only could be used for soybean quality genetic improvements in future, but also offered some evidences for reveal the negative relationships between seed protein and oil contents in soybean.

Key words: soybean, protein, oil, QTLs, epistatic effects, gene interactions

摘要： 大豆籽粒富含蛋白与脂肪，是人类植物蛋白与食用油重要来源；然而，蛋白、脂肪含量属多基因控制数量性状，尽管已有相关QTLs报道，但多是针对单个QTL进行分析，而很少有关于上位性QTLs的报道。鉴于此，利用大豆RIL群体，在4种环境条件下评价其籽粒蛋白与脂肪含量，结合SNP基因型进行上位性QTLs分析发现，定位到48对控制籽粒蛋白、55对控制籽粒脂肪含量上位性QTLs，涉及大豆所有染色体；进一步分析发现，有19对上位性QTLs同时与籽粒蛋白和脂肪含量相关，具体包括12对定位区间完全相同的QTLs、2对定位区间含共同标记的QTLs以及5对定位区间距离不超过5 cM的QTLs；同时发现，19对上位性QTLs分布在除11号染色体以外的19条染色体，其中以13号染色体分布数量最多，其次为1号染色体。上述结果不仅增添了控制大豆蛋白与脂肪含量上位性QTLs，而且为揭示二者之间的负相关关系提供了QTL间/基因间互作方面的分子证据。

关键词: 大豆, 蛋白, 脂肪, QTLs, 上位性效应, 基因互作