Shanghai Academy of Agricultural Sciences, Shanghai, 201403, China.
Sci Rep. 2021 Dec 3;11(1):23382. doi: 10.1038/s41598-021-02912-w.
Rapeseed, a major oil crop in the world, is easily affected by low-temperature stress. A low temperature delays seed germination and increases seedling mortality, adversely affecting rapeseed growth and production. In the present study, a tolerant cultivar (Huyou21) was crossed with a susceptible genotype (3429) to develop a mapping population consisting of 574 F progenies and elucidate the genetic mechanisms of seed germination under low temperatures. Two quantitative trait loci (QTL) for low-temperature germination (LTG) were detected, one on chromosome A09 (named qLTGA9-1) and the other on chromosome C01 (named qLTGC1-1), using the QTL-seq approach and confirmed via linkage analysis in the mapping population. Further, qLTGA9-1 was mapped to a 341.86 kb interval between the SSR markers Nys9A212 and Nys9A215. In this region, 69 genes including six specific genes with moderate or high effect function variants were identified based on the Ningyou7 genome sequence. Meanwhile, qLTGC1-1 was mapped onto a 1.31 Mb interval between SSR markers Nys1C96 and Nys1C117. In this region, 133 genes including five specific genes with moderate effect function variants were identified. These specific genes within the two QTL could be used for further studies on cold tolerance and as targets in rapeseed breeding programs.
油菜是世界上主要的油料作物之一，容易受到低温胁迫的影响。低温会延迟种子萌发并增加幼苗死亡率，从而对油菜的生长和生产产生不利影响。在本研究中，将一个耐低温品种（Huyou21）与一个敏感基因型（3429）杂交，构建了一个由 574 个 F 代组成的作图群体，以阐明低温下种子萌发的遗传机制。利用 QTL-seq 方法检测到了两个与低温萌发（LTG）相关的数量性状位点（QTL），一个位于 A09 染色体上（命名为 qLTGA9-1），另一个位于 C01 染色体上（命名为 qLTGC1-1），并通过在作图群体中的连锁分析进行了验证。进一步将 qLTGA9-1 定位在 SSR 标记 Nys9A212 和 Nys9A215 之间的 341.86kb 区间内。在这个区域内，根据宁油 7 号基因组序列，鉴定出了包括 6 个具有中等或高效应功能变异的特异基因在内的 69 个基因。同时，将 qLTGC1-1 定位在 SSR 标记 Nys1C96 和 Nys1C117 之间的 1.31Mb 区间内。在这个区域内，鉴定出了包括 5 个具有中等效应功能变异的特异基因在内的 133 个基因。这两个 QTL 内的特异基因可用于进一步研究油菜的耐冷性，并作为油菜育种计划中的目标。
