【作者】 高帆；

【导师】 李艳琴； 张宗文；

【作者基本信息】 山西大学 ， 生物化学与分子生物学， 2010， 硕士

【摘要】 本研究利用AFLP和SSR两种分子标记方法研究了50份国内苦荞优异种质材料的遗传多样性,并对这两种分子标记系统进行了比较。用19对AFLP引物组,检测到了211个AFLP特异性标记,PIC值变幅为0.0241-0.1918；用19对SSR引物组检测到了160个基因特异性标记,PIC值变幅为0.5908-0.9992。UPGMA聚类结果显示,当相似系数为0.790时,AFLP标记可将供试材料分为五个组群：当相似系数为0.578时,SSR标记可将供试材料分为四个组群。比较发现,两种分子标记划分结果不太一致。但通过比较两种分子标记的遗传多样性参数值,证实这两种分子标记系统均适合于苦荞遗传多样性研究。通过筛选,从中发现了一些适宜遗传多样性分析和杂交亲本材料选择的优势引物组合。这不仅对我国苦荞种质资源的遗传多样性保护提供了借鉴,也为国内优异苦荞品种的选育提供了很好的参考价值。此外,本研究还将对苦荞遗传图谱的构建、重要农艺性状基因的标记定位、荞麦起源研究提供了有益的参考价值。本研究还利用经典的RACE法成功地克隆出控制苦荞黄酮代谢合成的关键酶基因——查尔酮合酶(CHS)基因,确定了其完整的开放性阅读框(ORF)。用生物信息学手段分析预测了苦荞中该酶的基本理化性质和同源性,并用临接法构建了系统发生树,初步确定了苦荞以及其它植物中该酶的进化地位和方向。本实验的研究成果为下一步该基因转化及功能验证打下了良好的基础,并对今后用分子手段改良苦荞品质,即分子辅助选育高黄酮含量的苦荞优异品种具有重要意义。更多还原

【Abstract】 We studied the genetic diversity of 50 elite tartary buckwheat (Fagopyrum tataricum) germplasm by Amplified Fragments Length Polymorphism marker (AFLP) and Simple Sequence Repeat marker (SSR). Meanwhile, we had a comparison on effectiveness of two molecular markers systems. The results showed that 211 special AFLP markers were detected by 19 AFLP primer pairs and 160 special SSR markers by 19 SSR primer pairs. The Polymorphism Information Content (PIC) value was from 0.0241 to 0.1918 for AFLP and from 0.5908 to 0.9992 for SSR, respectively. The clustering analysis by Unweighted Pair Group Method with Arithmetic Mean (UPGMA) indicated that these germplasm resources could be divided into five clusters when the similarity coefficient was 0.790, and could be divided into four clusters when the similarity coefficient was 0.578.Although the results were not so consistent by the two kinds of markers, both of them were effective for studying tartary buckwheat genetic diversity. Moreover, we identified some good molecular markers primer pairs for F. tataricum, which will be very useful for assessing genetic diversity and identifying more appropriated varieties for breeding. Fianally, our work will also have a important reference on constructing more complete and detailed genetic linkage map, locating some important agronomic trait genes and determining the origion of F. tataricum.We cloned the key enzyme, chalcone synthase (CHS) gene responsible for synthesizing flavonoid in tartary buckwheat by Rapid Amplification of cDNA Ends (RACE), and got its Open Reading Frame (ORF).We analysed basic physicochemical properties and homology of the enzyme gene, and constructed the phylogenetic tree of gene family by neighbor-joining, which confirmed its evolution status and origin in F. tataricum.Our research provided a base on further study on its transform and functional testing. Moreover, it will paly an important role o molecular assistant breeding for the excellent F. tataricum varieties with high flavonoid content.更多还原