KEY MESSAGE: ddRAD-seq-based high-density genetic map comprising 2595 loci identified a major and consensus QTL with a linked marker in a 0.8-Mb physical interval for oil content in peanut. Enhancing oil content is an important breeding objective in peanut. High-resolution mapping of quantitative trait loci (QTLs) with linked markers could facilitate marker-assisted selection in breeding for target traits. In the present study, a recombined inbred line population (Xuhua 13 × Zhonghua 6) was used to construct a genetic map based on double-digest restriction-site-associated DNA sequencing (ddRAD-seq). The resulting high-density genetic map contained 2595 loci, and spanned a length of 2465.62 cM, with an average distance of 0.95 cM/locus. Seven QTLs for oil content were identified on five linkage groups, including the major and stable QTL qOCA08.1 on chromosome A08 with 10.14-27.19% phenotypic variation explained. The physical interval of qOCA08.1 was further delimited to a ~ 0.8-Mb genomic region where two genes affecting oil synthesis had been annotated. The marker SNPOCA08 was developed targeting the SNP loci associated with oil content and validated in peanut cultivars with diverse oil contents. The major and stable QTL identified in the present study could be further dissected for gene discovery. Furthermore, the tightly linked marker for oil content would be useful in marker-assisted breeding in peanut.

中文翻译：

---

花生（Arachis hypogaea L.）的主要和共有数量性状的油分含量高分辨率映射到A08染色体上的〜0.8-Mb区。

关键信息：包含2595个基因座的基于ddRAD-seq的高密度遗传图谱确定了一个主要且共有的QTL，带有一个链接标记，其物理间隔为0.8-Mb，用于测定花生中的油含量。提高含油量是花生的重要育种目标。带有关联标记的定量性状基因座（QTL）的高分辨率作图可以促进目标性状育种中标记辅助选择。在本研究中，使用重组自交系群体（徐化13×中华6）构建基于双消化限制性位点相关DNA测序（ddRAD-seq）的遗传图谱。所得的高密度遗传图谱包含2595个位点，长度为2465.62 cM，平均距离为0.95 cM /基因座。在五个连锁组上确定了七个含油QTL，包括主要和稳定的QTL qOCA08。解释了A08染色体上的1，具有10.14-27.19％的表型变异。qOCA08.1的物理间隔进一步限定在〜0.8-Mb基因组区域，其中注释了两个影响石油合成的基因。针对与油含量相关的SNP位点开发了标记SNPOCA08，并在具有不同油含量的花生品种中进行了验证。在本研究中确定的主要和稳定的QTL可以进一步解剖以发现基因。此外，油含量紧密相关的标记物可用于花生的标记物辅助育种。针对与油含量相关的SNP位点开发了标记SNPOCA08，并在具有不同油含量的花生品种中进行了验证。在本研究中确定的主要和稳定的QTL可以进一步解剖以发现基因。此外，油含量紧密相关的标记物可用于花生的标记物辅助育种。针对与油含量相关的SNP位点开发了标记SNPOCA08，并在具有不同油含量的花生品种中进行了验证。在本研究中确定的主要和稳定的QTL可以进一步解剖以发现基因。此外，油含量紧密相关的标记物可用于花生的标记物辅助育种。