【作者】 宋立君；

【导师】 柳李旺；

【作者基本信息】 南京农业大学 ， 蔬菜学， 2009， 硕士

【摘要】 萝卜(Raphanus sativus L)是起源于我国的一种重要蔬菜作物,种质资源十分丰富。随着人们生活水平提高,品质性状成为当前育种工作的重点领域。构建分子标记遗传图谱是进行重要园艺性状定位研究的基础。进行萝卜主要品质性状遗传作图,能够解析品质性状遗传基础,有利于分子标记辅助选择,加快高品质品种的培育进程。但目前国内外萝卜图谱的研究较少,有关萝卜主要品质性状的QTLs分析还未见报道。本研究利用分子标记构建了萝卜遗传连锁图谱,并进行主要品质性状的QTLs分析。研究结果将为解析萝卜主要品质性状的遗传基础研究,促进品质育种工作提供理论基础。本研究以综合品质性状较高的自交系Nau-XWH (R.sativus L.)和综合品质性状较低的自交系NAU-LHZ (R.sativus L. var raphanistroid)为材料,配制169个单株组成的F2群体,利用RAPD和SRAP分子标记构建萝卜遗传连锁图谱。共得到139个在亲本间存在差异,并能稳定遗传的分子标记用于连锁分析,得到一张包含80个标记、11个连锁群的遗传连锁图谱框架,包括30个RAPD标记和50个SRAP标记,图谱覆盖基因组总长度为739.5cM,标记间的平均图距为9.2cM。用于连锁分析的139个标记中还有59个标记保持独立而未能连锁,占总标记数量的42.4%。由于RAPD标记在染色体上的随机分布,以及染色体不同区段交换值异质性的存在,使得连锁群上产生了多个较大的间隙和小片段连锁群的出现。利用构建的萝卜遗传连锁图谱,采用WinQTLCart V2.5软件,分别对萝卜粗纤维含量、干物质含量、硝酸盐含量、可溶性总糖含量、蛋白质含量和Vc含量性状进行QTLs定位分析。共检测到7个与萝卜粗纤维含量对应的QTLs位点,分别位于LG1, LG3, LG5和LG7连锁群上,总共可解释10%的表型变异；检测到一个与干物质含量有关的QTLs位点,位于LG6连锁群上,可解释5.3%的表型变异；检测到7个与萝卜硝酸盐含量相对应的QTLs位点均位于LG1连锁群上,总共可解释21.8%的表型变异；共检测到2个与可溶性总糖含量相关的QTLs位点,且均位于LG1上,总共可解释12.5%的表型变异；共检测到11个与蛋白质含量对应的QTLs位点,分别位于LG1, LG3, LG5, LG6和LG7连锁群上,总共可解释89.9%的表型变异；在此遗传连锁图谱中没有检测到与Vc含量性状相关的QTLs位点。更多还原

【Abstract】 Radish(Raphanus sativus L.) is an important vegetable originated from China and has abundant germplasm.Quality traits are the important fields of breeding programs as the improvement of living standard. Construction of the molecular linkage map is the base for location of significant horticulture character. Mapping of radish main quality traits could elucidate the genetic base of quality traits and promote marker-assisted selection and breeding programs of high-quality. The study on genetic linkage map of radish was poor. QTLs (Quantitative Trait Loci) analysis of main quality traits in radish has not been reported. In this study, a genetic linkage map of radish was constructed with molecular markers and processed QTLs analysis of main quality traits in radish. The result could provide theoretical basis for parsed the genetic base of quality traits and promote breeding programs of high-quality.In this study, a genetic linkage map of radish was constructed with F2 population consisting of 169 individuals from a cross of inbred line NAU-XWH (R. sativus L.) (High nutrient quality)×inbred line NAU-LHZ (R.sativus L. var raphanistroid) (low nutritient quality) based on random amplified polymorphic DNA (RAPD) and Sequence related amplified polymorphism (SRAP) markers. A total of 139 marker loci which were assayed in the population,and the map consisted of 11 linkage groups which included 80 loci (30 RAPD and 50 SRAP),and spanned 739.5 cM of the Radish genome with an average distance of 9.2 cM between two markers.Fifty-nine markers were still unlinked, accounting for 42.4% of total markers. There were several big gaps and some little linkage groups in the map due to that RAPD markers are random distributed on the chromosome and the cross-over value between different sections of chromosome are heterogenous.Based on the genetic linkage map and WinQTLCart V2.5, the QTLs location analysis of crude fiber content, dry matter content, nitrate content, total soluble sugar content, protein content and Vc content traits of radish was generated. Seven putative QTLs for crude fiber content were detected and located on LG01, LG03, LG05 and LG07,respectively, which explained 10% of the total phenotypic variance; One putative QTLs for dry matter content trait were detected and located on LG06, which explained 5.3% of the total phenotypic variance; seven putative QTLs for nitrate content were detected and located on LG01,which explained 21.8% of the total phenotypic variance; two putative QTLs for total soluble sugar content were detected and located on LG01, which explained 12.5% of the total phenotypic variance; eleven putative QTLs for protein content were detected and located on LG01, LG03, LG05, LG6 and LG07,respectively, which explained 89.9% of the total phenotypic variance; none putative QTLs for Vc content were detected in this genetic linkage map.更多还原