Soybean is the world’s largest source of protein for animal feed and the second largest source of vegetable oil. Improving the seed protein of soybean without negatively affecting yield and oil content is an important goal for soybean breeders. A population consisting of 132 recombinant inbred lines (RILs) was developed by crossing an elite breeding line, G00-3213 with a plant introduction, PI 594458A, with elevated protein content. In 2016 and 2017, each of the RILs was grown as a single row in Watkinsville, GA, while in 2018, the population was grown at two locations. The seed composition of RILs was analyzed with near-infrared (NIR) spectroscopy. The RIL population was genotyped using the SoySNP6k BeadChip for quantitative trait locus (QTL) mapping. Significant genotype × environment interaction was observed. QTL analyses in and across four environments identified 16, 10, 10, 16, and 5 QTLs for protein, oil, sucrose, and normalized cysteine and methionine contents, respectively. QTLs for protein content identified on chromosomes (Chrs) 3, 6, 13, and 20 were detected in multiple environments. Eight genomic regions on Chrs 3, 6, 8, 10, 13, 17, and 20 were detected that influenced two to four traits, indicating that pleiotropic or linkage effects of these loci may influence multiple seed composition traits. The results of this research provide additional genomic resources for genetic improvement of seed composition and help breeders to better understand the environmental impacts on these QTLs.

大豆是世界上最大的动物饲料蛋白质来源和第二大植物油来源。在不对产量和含油量产生负面影响的情况下提高大豆种子蛋白是大豆育种者的一个重要目标。通过将优良育种系 G00-3213 与蛋白质含量升高的植物引种 PI 594458A 杂交，开发出由 132 个重组自交系 (RIL) 组成的群体。2016 年和 2017 年，每个 RIL 在佐治亚州沃特金斯维尔作为单行种植，而 2018 年，种群在两个地点种植。使用近红外 (NIR) 光谱分析 RIL 的种子成分。使用 SoySNP6k BeadChip 对 RIL 群体进行基因分型，以进行数量性状基因座 (QTL) 作图。观察到显着的基因型×环境相互作用。在四种环境中和跨四种环境的 QTL 分析分别鉴定了蛋白质、油、蔗糖以及标准化半胱氨酸和蛋氨酸含量的 16、10、10、16 和 5 个 QTL。在多种环境中检测到在 3、6、13 和 20 号染色体 (Chrs) 上鉴定的蛋白质含量 QTL。检测到 Chrs 3、6、8、10、13、17 和 20 上的 8 个基因组区域影响 2 至 4 个性状，表明这些基因座的多效性或连锁效应可能影响多个种子组成性状。这项研究的结果为种子组成的遗传改良提供了额外的基因组资源，并帮助育种者更好地了解环境对这些 QTL 的影响。