Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China.
Plant Germplasm Introduction and Testing Research, United States Department of Agriculture-Agricultural Research Service, Prosser, WA, USA.
Plant Genome. 2020 Nov;13(3):e20045. doi: 10.1002/tpg2.20045. Epub 2020 Sep 26.
Flowering time is an important agronomic trait of alfalfa (Medicago sativa L.). Managing flowering time can produce economic benefits for farmers. To understand the genetic basis of this trait, quantitative trait loci (QTL) mapping was conducted in a full-sib population that consisted of 392 individuals segregating based on flowering time. High density linkage maps were constructed using single nucleotide polymorphism (SNP) markers generated by genotyping-by-sequencing (GBS). The linkage maps contained 3,818 SNP markers on 64 linkage groups in two parents. The average marker density was 4.33 cM for Parent 1 (P1) and 1.47 cM for Parent 2 (P2). Phenotypic data for flowering time was collected for three years at one location. Twenty-eight QTLs were identified associated with flowering time. Eleven QTLs explained more than 10% of the phenotypic variation. Among them, five main effect QTLs located on linkage group (LG) 7D of P1 and five main effect QTLs located on LG 6D of P2 were identified. Three QTLs were co-located with other QTLs. The identified linked markers to QTLs could be used for marker-assisted selection in breeding programs to develop new alfalfa varieties to modulate flowering time.
开花时间是紫花苜蓿（Medicago sativa L.）的一个重要农艺性状。管理开花时间可以为农民带来经济效益。为了了解该性状的遗传基础，对基于开花时间分离的 392 个个体的全同胞群体进行了数量性状位点（QTL）作图。使用通过测序（GBS）基因型生成的单核苷酸多态性（SNP）标记构建了高密度连锁图谱。连锁图谱在两个亲本的 64 个连锁群中包含 3818 个 SNP 标记。亲本 1（P1）的平均标记密度为 4.33 cM，亲本 2（P2）为 1.47 cM。开花时间的表型数据在一个地点收集了三年。鉴定出与开花时间相关的 28 个 QTL。其中 11 个 QTL 解释了超过 10%的表型变异。其中，在 P1 的连锁群 7D 和 P2 的连锁群 6D 上分别鉴定到 5 个主效 QTL。三个 QTL 与其他 QTL共定位。鉴定到的与 QTL 连锁的标记可用于标记辅助选择，以开发新的紫花苜蓿品种来调节开花时间。
