甘蓝型油菜早熟性状遗传分析与基因定位

Early-matured rapeseed is the bottleneck of the cultivation mode of rice- rice-rapeseed, is the base to rapeseed planting in the large area winter fallow field in central-south china, which guarantee the security of edible oils for the citizen. But the breeding of early-matured rapeseed has no substantial progress in our country, without ideal early-matured rapeseed cultivar .Genetic analysis and gene mapping of early-matured traits in rapeseed is the theoretical basis for breeding,which would effectively improve the efficiency of rapeseed breeding.Our group collected a landrace in south Jiangxi province ,named "Huqianzao”. A photosensitive spring rapeseed "Global"used as female to crossed with a DH line from "Huqianzao”,and 340 DH lines were created by microspore culture with the hybrid. 190 DH lines which choosed by field identification and Molecular identification will constitute the mapping population with the two parents. And a high-resolution genetic map would be constructed with mass polymorphism SNP makers by re-sequencing. The traits of early maturity which identificated through years of multi-point test would be used for genetic analysis and gene mapping. And early maturity varieties may be breeded by using the excellent DH lines from the population.

早熟油菜是稻-稻-油三熟制栽培模式的瓶颈，是南方亿亩冬闲田油菜种植的基础，是我国食用油安全的重要保障。但是我国早熟油菜的育种一直没有得到突破性进展。开展早熟油菜的遗传研究和基因定位可为育种提供理论基础，有效提高育种效率。本研究从江西南部收集到地方早熟品种“花前早”，该品种具有冬性弱、开花期较早、成熟期早、花期抗寒性好等早熟油菜必需的优良性状,是开展早熟性状研究和品种选育的极佳资源。以感光性春油菜品种“Global”做母本，“花前早”DH系做父本，杂交后经小孢子培养创建了340个株系组成的DH群体。经田间和分子标记鉴定，选择190个DH系和双亲组成作图群体，应用重测序技术获取海量多态性标记构建一张高密度遗传图谱；通过多年多点试验鉴定DH群体早熟相关性状，并进行遗传分析和基因定位，以指导早熟油菜品种选育；同时从群体中鉴定的早熟株系可应用于早熟品种选育。

本研究以地方早熟品种“花前早”为材料基础，构建了190个DH株系和双亲组成的作图群体，通过对群体的多年多点田间试验，对与早熟相关的开花期、终花期、成熟期进行调查。分析发现早熟相关性状复合数量性状遗传模式。对作图群体进行全基因重测序，构建了由874,995个高质量多态性的SNP标记组成的高密度遗传图谱，利用此遗传图谱对油菜的早熟性状进行QTL定位，检测到30个早熟相关性状QTL位点。结合甘蓝型油菜基因组测序结果，对定位区间基因做功能注释，预测并筛选到29个与油菜早熟相关的候选基因，为解析早熟油菜形成机理奠定基础。项目发表研究论文1篇，项目申报专利2项，授权专利1项，育成油菜品种1个。