Desta Zeratsion Abera, de Koning Dirk-Jan, Ortiz Rodomiro
Department of Plant Breeding, Swedish University of Agricultural Sciences, Sundesvagen 10 Box 101, 23053, Alnarp, Sweden.
Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences, Box 7023, 75007, Uppsala, Sweden.
Heredity (Edinb). 2020 Apr;124(4):579-591. doi: 10.1038/s41437-020-0296-x. Epub 2020 Feb 19.
Lepidium campestre (L.) or field cress is a multifaceted oilseed plant, which is not yet domesticated. Moreover, the molecular and genetic mechanisms underlying the domestication traits of field cress remain largely elusive. The overarching goal of this study is to identify quantitative trait loci (QTL) that are fundamental for domestication of field cress. Mapping and dissecting quantitative trait variation may provide important insights into genomic trajectories underlying field cress domestication. We used 7624 single nucleotide polymorphism (SNP) markers for QTL mapping in 428 F interspecific hybrid individuals, while field phenotyping was conducted in F segregating families. We applied multiple QTL mapping algorithms to detect and estimate the QTL effects for seven important domestication traits of field cress. Verification of pod shattering across sites revealed that the non-shattering lines declined drastically whereas the shattering lines increased sharply, possibly due to inbreeding followed by selection events. In total, 1461 of the 7624 SNP loci were mapped to eight linkage groups (LGs), spanning 571.9 cM map length. We identified 27 QTL across all LGs of field cress genome, which captured medium to high heritability, implying that genomics-assisted selection could deliver domesticated lines in field cress breeding. The use of high throughput genotyping can accelerate the process of domestication in novel crop species. This is the first QTL mapping analysis in the field cress genome that may lay a foundational framework for positional or functional QTL cloning, introgression as well as genomics-assisted breeding in field cress domestication.
野油菜（Lepidium campestre (L.)），即田芥菜，是一种具有多种用途的油料作物，但尚未被驯化。此外，田芥菜驯化性状背后的分子和遗传机制在很大程度上仍不清楚。本研究的总体目标是确定对田芥菜驯化至关重要的数量性状位点（QTL）。绘制和剖析数量性状变异可能为田芥菜驯化的基因组轨迹提供重要见解。我们使用7624个单核苷酸多态性（SNP）标记对428个种间杂交个体进行QTL定位，同时在F分离群体中进行田间表型分析。我们应用多种QTL定位算法来检测和估计田芥菜七个重要驯化性状的QTL效应。不同地点对荚果炸裂情况的验证表明，不炸裂品系急剧减少，而炸裂品系急剧增加，这可能是由于近亲繁殖后再进行选择事件导致的。在7624个SNP位点中，共有1461个被定位到8个连锁群（LGs）上，图谱长度为571.9 cM。我们在田芥菜基因组的所有LGs上鉴定出27个QTL，这些QTL具有中等至高的遗传力，这意味着基因组辅助选择可以在田芥菜育种中培育出驯化品系。使用高通量基因分型可以加速新作物品种的驯化过程。这是田芥菜基因组中的首次QTL定位分析，可能为田芥菜驯化中的定位或功能QTL克隆、基因渗入以及基因组辅助育种奠定基础框架。
