四倍体马铃薯SNP遗传图谱的构建及重要农艺性状的关联分析

Conventional genotyping approaches are limited in their potential for exploiting marker/phenotype associations in gene discovery and applied research programmes. The availability of a potato genome sequence and high throughput sequencing platforms, provides a clear opportunity to convert this information into a gene-based marker platform that has potential impact on all future potato breeding efforts. Association mapping approaches can be used to dissect trait variation across broader germplasm populations than conventional genetic mapping and can resolve complex trait variation. This project will employ the very latest genome sequencing technologies (GBS, Genotyping by Sequencing), using an association genetics approach, to analysis the tetropioid potato agronomic trait genetics and devolope the marker tools. The project will use a set of 200 diverse potato clones representing the different market sectors, and several traits relevant to yield, agronomic traits, tuber shapes, dormancy etc will be analysed simultaneously. We will identify genes and sequence-based markers underpinning a range of important agronomic traits. It will make use of genomics data to genetically analyse some of the most important potato traits, By coupling association mapping (uses historical and evolutionary recombination events at the population level) with a truly novel 'next gen' sequencing based approach GBS, the project has the potential to scan the whole genome for marker-trait associations at much more depth than is possible through any other existing genotyping approach. Trait data will be tested for associations with sequence variants (or 'alleles') detected in the sequence analysis. Alleles which 'explain' significant proportions of trait variation will be subjected to further analysis to allow them to be converted into genetic markers that can be deployed directly by potato breeders on large number of breeding clones in a cost-effective manner. The aims of this study is to identify the SNP markers closely associated with the traits and provide useful markers for marker-assisted selection in a tetraploid potato breeding programme.

四倍体马铃薯遗传方式复杂，传统的分子标记技术在性状-标记关联分析方面还存在较大局限性。全基因组测序的完成为马铃薯重要性状的遗传分析提供了全新平台，本项目拟采用最新测序分型（GBS, Genotyping by Sequencing）方法及结合关联作图，在四倍体水平下进行马铃薯重要农艺性状的遗传分析和分子标记开发。 项目拟选择200个具有代表性的四倍体马铃薯品种（系）构建自然群体，系统评价马铃薯抗病性、生育期、块茎形状、肉色等重要农艺性状，同时采用GBS方法对200份材料进行全基因组数据扫描，构建单核苷酸多态性（SNP）分子标记遗传图谱，开展标记-性状关联分析（MTA, marker-trait association），筛选影响马铃薯重要农艺性状多态性位点，明晰相关位点的遗传效应，发掘可用于辅助育种的分子标记，为通过分子标记辅助选择改良马铃薯遗传性状提供技术支撑。

四倍体马铃薯遗传方式复杂，传统的分子标记技术在性状-标记关联分析方面还存在较大局限性。全基因组测序的完成为马铃薯重要性状的遗传分析提供了全新平台，本项目拟采用最新测序分型（GBS, Genotyping by Sequencing）方法及结合关联作图，在四倍体水平下进行马铃薯重要农艺性状的遗传分析和分子标记开发。.项目通过对292份马铃薯品种及种质资源进行SSR群体结构分析，表明可分为两个亚群P1和P2，P1群体遗传狭窄，为育种选择驯化的结果，P2群体遗传多样性丰富，有更多的野生种资源遗传背景。对778个基因型进行了农艺性状、块茎性状、产量性状等表型评价，通过SLAF-seq（Specific-Locus Amplified Fragment Sequencing）测序分型，获得16,531,339个SNP标记。基于SNP标记，采用不同的统计模型，对重要农艺性状进行了关联作图，通过全基因组标记-性状关联分析，定位获得控制抗晚疫病性、成熟期、植株高度、茎粗等农艺性状的主效QTL位点；对位于5号、9号和11号染色体上基因组区域进行了功能分析及分子标记开发，研究结果为通过分子标记辅助选择改良马铃薯遗传性状提供技术支撑。项目在研期间发表研究论文5 篇，其中SCI 论文2篇，中文核心期刊3篇。发表会议论文1篇，出版编著1部，构建数据库1个，获得专利1项。