Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences; Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Ministry of Agriculture, Beijing, 100081, China.
Copenhagen Plant Science Center and Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg C, Denmark.
BMC Genomics. 2019 May 14;20(1):371. doi: 10.1186/s12864-019-5769-z.
Barbarea vulgaris is a wild cruciferous plant and include two distinct types: the G- and P-types named after their glabrous and pubescent leaves, respectively. The types differ significantly in resistance to a range of insects and diseases as well as glucosinolates and other chemical defenses. A high-density linkage map was needed for further progress to be made in the molecular research of this plant.
We performed restriction site-associated DNA sequencing (RAD-Seq) on an F population generated from G- and P-type B. vulgaris. A total of 1545 SNP markers were mapped and ordered in eight linkage groups, which represents the highest density linkage map to date for the crucifer tribe Cardamineae. A total of 722 previously published genome contigs (50.2 Mb, 30% of the total length) can be anchored to this high density genetic map, an improvement compared to a previously published map (431 anchored contigs, 38.7 Mb, 23% of the assembly genome). Most of these (572 contigs, 31.2 Mb) were newly anchored to the map, representing a significant improvement. On the basis of the present high-density genetic map, 37 QTL were detected for eleven traits, each QTL explaining 2.9-71.3% of the phenotype variation. QTL of glucosinolates, leaf size and color traits were in most cases overlapping, possibly implying a functional connection.
This high-density linkage map and the QTL obtained in this study will be useful for further understanding of the genetic of the B. vulgaris and molecular basis of these traits, many of which are shared in the related crop watercress.
菘蓝是一种野生十字花科植物，包含两种截然不同的类型：G 型和 P 型，分别因其无毛和有毛的叶子而得名。这两种类型在对一系列昆虫和疾病以及硫代葡萄糖苷和其他化学防御的抗性方面有显著差异。为了在这种植物的分子研究方面取得进一步进展，需要构建一个高密度的连锁图谱。
我们对来自 G 型和 P 型菘蓝的 F 群体进行了限制性位点相关 DNA 测序（RAD-Seq）。共检测到 1545 个 SNP 标记，并在 8 个连锁群中进行了定位和排序，这是迄今为止十字花科芸薹族植物中密度最高的连锁图谱。总共 722 个先前公布的基因组 contigs（50.2 Mb，占总长度的 30%）可以锚定到这个高密度遗传图谱上，这比之前公布的图谱（431 个锚定 contigs，38.7 Mb，组装基因组的 38.7%）有所改进。其中大多数（572 个 contigs，31.2 Mb）是新锚定到图谱上的，这是一个显著的改进。基于目前的高密度遗传图谱，检测到了 11 个性状的 37 个 QTL，每个 QTL 解释了 2.9-71.3%的表型变异。硫代葡萄糖苷、叶片大小和颜色性状的 QTL 大多数情况下是重叠的，这可能暗示着它们在功能上存在联系。
本研究构建的高密度连锁图谱和获得的 QTL 将有助于进一步了解菘蓝的遗传基础和这些性状的分子基础，其中许多性状在相关作物西洋菜中也存在。
