Beijing Vegetable Research Center (BVRC), Beijing Academy of Agriculture and Forestry Science (BAAFS), Beijing 100097, China; Department of Crop Genetics, John Innes Centre, Norwich NR4 7UH, UK; Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (North China), Ministry of Agriculture, Beijing 100097, China; Beijing Key Laboratory of Vegetable Germplasm Improvement, Beijing 100097, China.
Beijing Vegetable Research Center (BVRC), Beijing Academy of Agriculture and Forestry Science (BAAFS), Beijing 100097, China; Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (North China), Ministry of Agriculture, Beijing 100097, China; Beijing Key Laboratory of Vegetable Germplasm Improvement, Beijing 100097, China.
Mol Plant. 2018 Nov 5;11(11):1360-1376. doi: 10.1016/j.molp.2018.08.006. Epub 2018 Sep 12.
Chinese cabbage is the most consumed leafy crop in East Asian countries. However, premature bolting induced by continuous low temperatures severely decreases the yield and quality of the Chinese cabbage, and therefore restricts its planting season and geographic distribution. In the past 40 years, spring Chinese cabbage with strong winterness has been selected to meet the market demand. Here, we report a genome variation map of Chinese cabbage generated from the resequencing data of 194 geographically diverse accessions of three ecotypes. In-depth analyses of the selection sweeps and genome-wide patterns revealed that spring Chinese cabbage was selected from a specific population of autumn Chinese cabbage around the area of Shandong peninsula in northern China. We identified 23 genomic loci that underwent intensive selection, and further demonstrated by gene expression and haplotype analyses that the incorporation of elite alleles of VERNALISATION INSENTIVE 3.1 (BrVIN3.1) and FLOWER LOCUS C 1 (BrFLC1) is a determinant genetic source of variation during selection. Moreover, we showed that the quantitative response of BrVIN3.1 to cold due to the sequence variations in the cis elements of the BrVIN3.1 promoter significantly contributes to bolting-time variation in Chinese cabbage. Collectively, our study provides valuable insights into the genetic basis of spring Chinese cabbage selection and will facilitate the breeding of bolting-resistant varieties by molecular-marker-assisted selection, transgenic or gene editing approaches.
大白菜是东亚国家消费最多的叶菜作物。然而，连续低温引起的过早抽薹严重降低了大白菜的产量和品质，从而限制了其种植季节和地理分布。在过去的 40 年中，已经选择了具有较强耐寒性的春大白菜来满足市场需求。在这里，我们报告了一个由三个生态型的 194 个地理多样的大白菜品种的重测序数据生成的大白菜基因组变异图谱。对选择扫描和全基因组模式的深入分析表明，春大白菜是从中国北方山东半岛地区的秋大白菜特定群体中选择出来的。我们鉴定了 23 个经历了强烈选择的基因组位点，并通过基因表达和单倍型分析进一步证明， VernalisatIon INSENTIVE 3.1（BrVIN3.1）和 FLOWER LOCUS C 1（BrFLC1）的优异等位基因的整合是选择过程中变异的一个决定遗传来源。此外，我们表明，由于 BrVIN3.1 启动子顺式元件的序列变异，BrVIN3.1 对低温的定量反应显著导致了大白菜抽薹时间的变化。总的来说，我们的研究为春大白菜选择的遗传基础提供了有价值的见解，并将通过分子标记辅助选择、转基因或基因编辑方法促进抗抽薹品种的培育。
