萝卜是云贵高原乃至全国广泛栽培的重要蔬菜作物，但先期抽薹严重影响冬春和春夏萝卜品质和产量，选育耐抽薹品种是解决该问题的重要手段。目前用于准确鉴定萝卜耐抽薹性状的分子标记非常少，关于控制萝卜耐抽薹相关QTL位点的研究缓慢，制约了萝卜耐抽薹的分子育种进程。项目拟利用基于简化基因组测序的基因分型技术（Genotyping-by-sequencing，GBS）对云贵高寒山地不同生态环境下的77份萝卜资源进行遗传结构分析；利用筛选鉴定出的2对抽薹性状差异显著的高代自交系材料组配F2︰3群体；发掘与耐抽薹相关的SNP位点并开发CAPS分子标记；构建遗传连锁图谱，对耐抽薹相关QTL位点进行定位。研究成果不仅有助于深入理解萝卜耐抽薹性状的遗传机制，对加速萝卜耐抽薹分子标记辅助育种亦具有重要的理论和实践意义。

Radish (Raphanus sativus L.) is one of the most important vegetative crops cultivated widely in Yunnan-Guizhou Plateau and nation widely. However, pre-mature bolting has become one of the limiting factors for the yield and quality of Winter-Spring radish. The effective approach to solve this problem is to breeding the bolting-resistant varieties. However, there are very limited molecular markers currently that have been developed for screening and identifying the bolting-resistant traits of radish, and the study about QTLs mapping associated with bolting-resistance has been slower, which has significantly retarded the progress in the molecular breeding of bolting-resistant radish varieties. This project plan to screen and identify the novel germplasms of Raphanus sativus L. with strong bolting-resistant traits from a population consisting of 77 lines mainly collected from Yunnan-Guizhou Plateau. The genotyping-by-sequencing (GBS) technology will be deployed to analyze the genetic structure and genetic variation of this panel. Meanwhile, two pairs of bolting-resistant lines vs sensitive lines identified will be used to construct a F2:3 mapping population, and GBS will be used for identifying high-quality of SNPs that will be used for develop CAPS makers. Then a high-density of genetic map will be constructed, and used for QTL mapping of bolting-resistant traits. The results will help us to gain deeper understanding about the genetic mechanisms of bolting-resistance, and to accelerate the marker-assistant breeding program for bolting-resistant radish varieties theoretically and practically.