梅花高密度遗传图谱构建及部分观赏性状QTL分析

发布时间：2018-01-12 15:30

  本文关键词：梅花高密度遗传图谱构建及部分观赏性状QTL分析　出处：《北京林业大学》2016年博士论文　论文类型：学位论文

  更多相关文章： 梅花 SLAF-seq 遗传连锁图谱 QTL分析 垂枝 精细定位

【摘要】：梅花(Prunus mume Sieb. et Zucc.)是中国传统名花,具有重要的文化及经济价值。培育集合多种优良观赏性状的新品种是梅花产业发展的关键,目前梅花新品种育种工作主要采用传统杂交育种途径,然而木本植物童期较长,此外观赏性状遗传机理复杂,直接找到控制这些性状的关键基因十分困难。通过构建高密度遗传连锁图谱及QTL定位分析,是找到控制复杂性状的关键遗传因子和紧密连锁分子标记的重要方法,但其在梅花中研究较少。为了挖掘控制梅花花色、花型、花瓣数、垂枝等性状的遗传因子及候选基因,本研究利用性状分离良好的‘六瓣’ב粉台垂枝’F1群体为试验材料,通过SLAF-seq技术进行大规模分子标记开发并构建了梅花高密度遗传连锁图谱,然后对F1群体这些观赏性状进行QTL分析及候选基因的挖掘。由于垂枝性状为木本植物特有性状,后续重点对其进行了精细定位及候选基因的挖掘。主要结论如下：(1)通过梅花杂交试验获得了在株型、花色、花型均有明显分离的F1作图群体‘六瓣’ב粉台垂枝’,该群体大小为387。在此基础上,利用SLAF-seq技术对梅花进行全基因组范围分子标记的开发,构建了梅花标记密度最大的一张遗传连锁图谱,共有8条连锁群,包含遗传标记8,007个,标记间平均遗传距离为0.195 cM。其中2号连锁群上标记数量最多为1,722个,遗传距离为263.84cM,6号连锁群上标记数量为698个,遗传距离为142.48cM。总图距为1,550.62 cM,覆盖梅花基因组64.31%,最终图谱上的SLAF标记在F1作图群体中的平均完整度为96%。(2)基于构建的梅花高密度遗传连锁图谱,采用复合区间作图法对梅花‘六瓣’ב粉台垂枝’F1群体15个生长、株型、花部相关重要性状进行了QTL定位分析。共检测到66个QTLs位点,利用梅花基因组注释信息筛选出58个可能的候选基因。(3)对垂枝梅与直枝梅枝条不同部位及发育阶段细胞结构、木材成分以及激素水平3个生理层面的差异进行了分析。发现垂枝梅与直枝梅在枝条近远轴面细胞排列、木质化程度均存在差异,且在垂枝梅枝条木质部细胞中存在淀粉体的缺失；木质素含量测定结果表明直枝梅枝条近轴面木质素含量比远轴面低,垂枝枝条近轴面木质素含量比远轴面高,田间观察发现梅花枝条生长初期并未表现出明显的垂枝表型,而在木质化过程中垂枝表型越来越明显,推测垂枝性状形成可能与枝条木质化过程的差异有关；采用液相质谱的方法对5个发育阶段垂枝梅和直枝梅枝条不同部位激素水平进行比较分析,推测GA3可能与垂枝表型形成有关。(4)根据垂枝性状遗传分析结果推测梅花垂枝性状可能由一个主效基因和一个或者多个微效基因共同控制。在此基础上采用三种统计分析方法将垂枝性状定位到梅花7号染色体10.54Mb-11.68Mb区域,同时10个SLAF分子标记被认为与梅花垂枝性状紧密连锁。在前期生理试验结果的基础上对垂枝候选区域进行候选基因筛选。最终,9个可能与枝条木质化相关,参与细胞壁及纤维素合成与降解的结构基因/酶类,以及9个被预测参与基因的转录调控的基因被推测与梅花垂枝性状形成相关。本研究构建的梅花高密度遗传连锁图谱将为后续重要性状的定位奠定基础,15个梅花重要性状QTL分析对指导这些复杂性状的分子育种具有重要意义,而垂枝性状的精细定位将为后续找到控制垂枝性状的基因奠定基础,同时为木本植物其他重要性状的定位提供一种研究策略。
[Abstract]:Plum (Prunus mume Sieb. et Zucc.) is China traditional flowers, has an important cultural and economic value. To cultivate new varieties of various sets of excellent ornamental traits is the key of plum industry development, the plum breeding of new varieties by traditional breeding work, but woody plant children over a long period of time, the ornamental characters of complex genetic mechanism direct, find the key genes controlling these traits is very difficult. The high density genetic linkage map and QTL mapping analysis of the construction, is an important method to find the key genetic factors controlling complex traits and molecular markers closely linked, but less research. In order to control mining in plum flower color, flower type, flower number, genetic factor and candidate gene pendula traits, this study uses characters of good separation "six flap '*' Pink Taiwan branches' F1 group as the experimental material, by SLAF-seq The technology for large-scale development of molecular markers and genetic linkage map of plum high density was established, and then the F1 group of these ornamental characters of mining and QTL analysis of the candidate genes. Because of the weeping traits of woody plant traits, the follow-up key has carried on the fine mapping and candidate gene mining. The main conclusions are as follows: (1) the plum hybridization experiments obtained in plant type, color, F1 mapping population 'patterns are obviously separated with six' x 'powder Taiwan branches', the population size of 387. on the basis of this, the development of molecular markers for genome wide Meihua using SLAF-seq technology, one of the largest plum marker density genetic linkage to build a map, a total of 8 linkage groups, including 8007 genetic markers, markers between the average genetic distance of 0.195 cM. markers in 2 linkage groups, including the number of up to 1722, the genetic distance was 263. 84cM, No. 6 linkage group mark number is 698, the genetic distance of 142.48cM. total length is 1550.62 cM, 64.31% SLAF markers covering the plum genome, the final map on average in F1 mapping population in the degree of 96%. (2) to construct the plum high density genetic linkage map based on composite interval mapping method of plant type on the "six petal plum '*' powder Taiwan branches' F1 Group 15 growth, flower related traits were important for QTL positioning analysis. 66 QTLs loci were detected by plum genome annotation screened 58 candidate genes. (3) the different parts of the vertical and straight plum plum branches and the developmental stages of cell structure, the difference of wood components and hormone level 3 physiological level were analyzed. Found weeping plum and plum branches in nearly straight abaxial cell arrangement, there are differences in the degree of lignification, and vertical plum branches of wood There is lack of starch cells; the determination results of lignin content shows that the straight plum branches adaxial than abaxial surface of the lignin content is low, the weeping branches of the adaxial surface lignin content than the abaxial surface of high field observation found plum branch growth early shows no significant branches in phenotype. In lignification of pendula phenotype is more and more obvious, the difference that branches and branches may form characters of the lignification process; using the method of liquid chromatography mass spectrometry on the 5 developmental stages of vertical and straight plum plum branches in different parts of hormone levels were compared, suggesting that GA3 may from the weeping phenotype formation. (4) according to the weeping genetic analysis results suggest that characteristics of Prunus mume could be controlled by a major gene and one or more minor genes. On the basis of using three methods of statistical analysis will be weeping traits to Mei Take the 10.54Mb-11.68Mb region on chromosome 7, and 10 SLAF markers were considered closely linked with characteristics of Prunus mume. Based on the previous physiological test results on the vertical branch candidate region candidate gene screening. Finally, 9 possible branches and lignification related genes involved in cell wall structure, / and cellulose synthesis and degradation enzymes, as well as 9 are predicted to be involved in transcriptional regulation gene presumably associated with characteristics of Prunus mume. The plum high density genetic linkage map will lay the foundation for the subsequent location of important traits, 15 plum blossom shaped QTL importance to guide the analysis of molecular breeding of these complex traits has important significance, and fine mapping of weeping traits will find the control for the subsequent pendula gene lay the foundation, at the same time as other important traits of woody plants provide a research strategy.

【学位授予单位】：北京林业大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：S685.17
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本文编号：1414863