大白菜抗病和晚抽薹性状的GWAS分析及其优异资源发掘

发布时间：2018-04-24 08:55

本文选题：大白菜 + 抗病性　；参考：《中国农业科学院》2016年博士论文

【摘要】：蔬菜品种抗逆性、抗病性和品质的优劣是其成败的要素。而相关性状优异基因资源发掘是实现分子育种的基础。本研究以203份来源广泛、类型丰富的大白菜高代自交系为试材,进行了耐抽薹性和5种主要病害抗病性的人工控制环境下的鉴定,筛选出一批优良的大白菜育种材料;根据核心种质的重测序结果,开发了覆盖全基因组的SNP标记,并开展了全基因组关联分析,以挖掘控制这些性状的候选区段;对28份大白菜自交系或杂交组合进行感官品质和营养品质评价,并分析了两者的关系,为大白菜育种提供借鉴。主要研究结果如下:1.在6类不同形态类型的大白菜种质中,以合抱卵圆型材料的晚抽薹性最好;获得14份晚抽薹材料,其中以07-458和12-577开花最迟,从春化结束到开花分别需53天和41天。2.获得高抗霜霉病、病毒病、黑腐病、黄萎病和根肿病的材料分别有7、3、0、28和12个;兼抗2~4种病害的材料共计93个,并从中筛选到12-85、13-108和09-894等15个综合抗病性表现优异的自交系材料。3.基于10个核心种质的重测序数据,开发了覆盖全基因组的1040个SNP标记,并对203份材料进行基因分型和遗传结构分析;群体被划分为4个亚群,分别是合抱卵圆类亚群、叠抱平头类亚群、叠抱直筒类亚群和混合类型亚群;亲缘关系分析表明,自交系间两两亲缘关系系数在0.2以下的超过92%,表明群体亲缘关系较远。4.选用182份自交系材料组成的自然群体开展晚抽薹和5种病害的全基因组关联分析,分别获得与耐抽薹性、开花天数、霜霉病、病毒病、黑腐病、黄萎病和根肿病抗性显著关联的5、2、2、5、2、5和8个共计29个位点或热点区,为进一步发掘候选基因提供了依据。5.以28个自交系或品种为试材,筛选出了7个感官品质较好的自交系材料,并分析得到感官品质回归方程:生食综合yr=0.3103+0.254x1(多汁度)+0.1762x2(甜度)+0.2216x3(脆度)+0.3199x4(鲜味),熟食综合yc=0.2044+0.2509x5(渣量)+0.2469x6(甜度)+0.1825x7(绵软度)+0.3231x8(鲜味)。通径分析结果表明,多汁度和甜度对大白菜生食综合评价影响较大;甜度对熟食影响最大。获得营养品质预测的回归方程yr=-32.1920+0.3893x1(水分)+1.1698x2(可溶性糖),yc=7.4971+0.7326x2(可溶性糖)-5.6688x3(有机酸)-2.1763x5(粗纤维),可以水分和可溶性糖对生食,可溶性糖、有机酸和粗纤维对熟食品质进行预测。
[Abstract]:The resistance, disease resistance and quality of vegetable varieties are the key factors of their success or failure. The discovery of excellent genetic resources for related traits is the basis of molecular breeding. In this study, 203 high-generation inbred lines of Chinese cabbage from a wide range of sources were used as materials to identify bolting tolerance and disease resistance of five major diseases in artificial controlled environment, and a number of excellent breeding materials were screened out. According to the resequencing results of the core collection, SNP markers covering the whole genome were developed, and the whole genome association analysis was carried out to mine candidate regions controlling these traits. Sensory quality and nutritional quality of 28 Chinese cabbage inbred lines or hybrid combinations were evaluated and the relationship between them was analyzed in order to provide reference for Chinese cabbage breeding. The main results are as follows: 1. Among the 6 types of Chinese cabbage germplasm with different morphological types, the late bolting was the best in the zygotic oval type, and 14 late bolting materials were obtained, of which 07-458 and 12-577 had the latest flowering time, and from the end of vernalization to flowering, it took 53 days and 41 days, respectively. The materials with high resistance to downy mildew, virus disease, black rot, verticillium wilt and root-swelling were obtained, and 93 inbred lines with excellent comprehensive disease resistance, such as 12-85Y13-108 and 09-894, were selected from the materials with high resistance to downy mildew, virus disease, verticillium wilt and root swelling respectively. Based on the resequenced data of 10 core collections, 1040 SNP markers covering the whole genome were developed and genotyping and genetic structure analysis were carried out in 203.The population was divided into 4 subgroups, one of which was zygotic oval subgroup. The analysis of genetic relationship showed that the coefficient of genetic relationship between inbred lines was less than 0.2, which indicated that the genetic relationship of the inbred lines was more than 92.4.The results showed that the genetic relationship between the two inbred lines was higher than that of the control group, and the relationship between the two inbred lines was less than 0.2, which indicated that the population had a far relationship with each other. The whole genome association analysis of late bolting and 5 diseases was carried out in 182 natural populations of inbred lines. The results were as follows: bolting tolerance, flowering days, downy mildew, virus disease and black rot, respectively. A significant correlation between Verticillium wilt and Rhizomegaly Resistance was found in 5, 2, 2, 5 and 8 sites, or hot spots, which provided a basis for further discovery of candidate genes. Seven inbred lines with better sensory quality were selected from 28 inbred lines or varieties. The regression equation of sensory quality was obtained as follows: raw food synthesis yr=0.3103 0.254x1 (juiciness) 0.1762x2 (sweetness) 0.2216x3 (crispness) 0.3199x4 (fresh taste), cooked food synthesis yc=0.2044 0.2509x5 (residue amount) 0.2469x6 (sweetness) 0.1825x7 (softness) 0.3231x8 (fresh taste). The results of path analysis showed that juicy degree and sweetness had great influence on the comprehensive evaluation of Chinese cabbage raw food, while sweetness had the greatest effect on cooked food. The regression equation yr=-32.1920 0.3893x1 (water) 1.1698x2 (soluble sugar) 7.4971 0.7326x2 (soluble sugar) -5.6688x3 (organic acid) -2.1763x5 (crude fiber) can predict the quality of cooked food with water and soluble sugar, soluble sugar, organic acid and crude fiber.
【学位授予单位】：中国农业科学院
【学位级别】：博士
【学位授予年份】：2016
【分类号】：S634.1

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