Seed coat cracking (SCC), particularly the Type-I irregular cracking, is critical in determining the quality of appearance and commercial value of soybean seeds. The objective of this study was to identify the quantitative trait loci (QTLs) for SCC with high-density genetic map. One hundred sixty-seven recombinant inbred lines (RILs) developed from a cross between Uram (SCC-resistant) and Chamol (SCC-susceptible) were evaluated for SCC over 2 years (2016–2017). The QTL analysis identified 12 QTLs located on chromosomes 2 (D1b), 6 (C2), 8 (A2), 9 (K), 10 (O), 12 (H), 19 (L), and 20 (I). Out of the 12 QTLs, qSC2-1, qSC9, SC10-1, qSC10-2, and qSC12 were novel QTLs and the other seven QTLs (qSC2-2, qSC2-3, qSC6, qSC8, qSC19-1, qSC19-2, and qSC20) were found to co-localize with the previously identified QTLs. The mean SCC of the RILs of early maturity group was significantly higher than that of the late maturity group, suggesting an association between SCC and maturity loci. In addition, although 10 QTLs were distantly located from the maturity loci (E1, E3, E4, E7, and E10), qSC10-1 and qSC10-2 co-localized with the maturity loci E2. The results obtained in this study provide useful genetic information on SCC which could be used in the SCC breeding programs.

中文翻译：

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高密度连锁图揭示了大豆 RIL 群体中 I 型种皮开裂的 QTL [Glycine max (L.) Merr.]

种皮开裂 (SCC)，尤其是 I 型不规则开裂，对于确定大豆种子的外观质量和商业价值至关重要。本研究的目的是利用高密度遗传图谱确定 SCC 的数量性状位点 (QTL)。在 2 年（2016-2017 年）期间，对由 Uram（抗 SCC）和 Chamol（SCC 易感）杂交产生的 167 个重组自交系（RIL）进行了 SCC 评估。QTL 分析确定了位于染色体 2 (D1b)、6 (C2)、8 (A2)、9 (K)、10 (O)、12 (H)、19 (L) 和 20 (I) 上的 12 个 QTL。在这 12 个 QTL 中，qSC2-1、qSC9、SC10-1、qSC10-2 和 qSC12 是新的 QTL，其他 7 个 QTL（qSC2-2、qSC2-3、qSC6、qSC8、qSC19-1、qSC19-2和 qSC20) 被发现与先前鉴定的 QTL 共定位。早熟组 RILs 的平均 SCC 显着高于晚熟组，表明 SCC 与成熟位点之间存在关联。此外，虽然有 10 个 QTL 远离成熟基因座（E1、E3、E4、E7 和 E10），但 qSC10-1 和 qSC10-2 与成熟基因座 E2 共定位。本研究中获得的结果提供了有用的 SCC 遗传信息，可用于 SCC 育种计划。