玉米株高QTL qPH3.2和qPH3.3的精细定位

发布时间：2019-03-01 07:26

【摘要】：玉米株高属于株型育种目标性状之一,不仅与玉米籽粒的机械化收获及抗倒伏相关,也与玉米产量密切相关,是玉米遗传育种研究的重要目标性状之一。在课题组前期工作中,利用高代回交重组自交系W1和W2构建的F2和F2:3群体在第三染色体上定位到两个主效QTL位点q PH3.2(C42-P17)和qPH3.3(C79-C103);在此基础上,本试验目标是利用剩余杂合群体对上述两个主效QTL进行重定位,鉴定其真实可靠性,进而利用目标区段的子代纯系和跨叠系精细定位qPH3.2和qPH3.3并对其进行遗传解析。本试验获得的主要结果如下:1、利用剩余杂合群体对qPH3.2进行重定位。将含有目标区段的2个剩余杂合单株自交构建分离群体,采用复合区间作图法和单标记分析法将qPH3.2剖分为2个主效QTL,分别命名为qPH3.2.1和qPH3.2.2。QTL重定位区间与初定位区间相一致,证实了QTL定位结果的准确性和真实性。2、qPH3.2.1的精细定位。将qPH3.2.1目标区段内的跨叠系纯系(1765株)在黄冈、山东进行一年两点试验,每点3次重复随机区组设计播种,将qPH3.2.1定位在标记Y72-Y91之间。随后利用Y72-Y91目标区段内筛选到的5种重组类型,交换单株自交构建的F2群体进行子代测验将q PH3.2.1定位在标YH305-Y72之间约7.6Mb范围内。3、qPH3.2.2的精细定位。将qPH3.2.2目标区段内的跨叠系纯系(2125株)在黄冈、山东进行一年两点试验,每点3次重复随机区组设计播种,将qPH3.2.2定位在标记P17-Y150之间。进而利用P17-Y150目标区段内筛选到的4种重组类型,不同类型的交换单株自交构建F2群体进行子代测验qPH3.2.2进一步精细定位,最终将qPH3.2.2定位在标记YH112-Y150之间约8Mb范围。4、利用剩余杂合群体对qPH3.3进行重定位。将含有目标区段的3个剩余杂合单株自交构建分离群体,采用复合区间作图法和单标记分析法对qPH3.3重定位,验证了初定位结果的准确性和真实性。5、qPH3.3的精细定位。根据重定位的结果,在目标区间筛选到11种重组类型。利用不同重组类型的交换单株自交构建的F2群体将qPH3.3定位在标记C79-C90之间约11Mb范围。
[Abstract]:The plant height of maize is one of the target traits of plant type breeding, which is not only related to the mechanization harvest and lodging resistance of maize seeds, but also closely related to the yield of maize. It is one of the important target traits in the research of maize genetics and breeding. In the previous work of our research group, two major QTL loci Q PH3.2 (C42-P17) and qPH3.3 (C79-C103) were located on the third chromosome in F2 and F2 population constructed by high-generation backcross recombination inbred lines W1 and W2. The two major loci, Q PH3.2 (C42-P17) and qPH3.3 (C79-C103), were located on the third chromosome. On this basis, the objective of this experiment is to relocate the two main effects of QTL using the residual heterozygous population, and to identify its true reliability. Furthermore, qPH3.2 and qPH3.3 were precisely mapped and analyzed by using the progeny lines and cross-overlapping lines of the target region. The main results obtained in this study are as follows: 1. The residual heterozygous population was used to relocate qPH3.2. Two residual heterozygous individual plants with target segment were used to construct the segregation population. The qPH3.2 was divided into two main effect QTL, by the method of compound interval mapping and single marker analysis. They are named as qPH3.2.1 and qPH3.2.2.QTL respectively, which are consistent with the initial location interval. The accuracy and authenticity of the QTL localization results are confirmed. 2, and the fine positioning of qPH 3.2.1 is confirmed. The crossing line pure lines (1765 strains) in the target region of qPH3.2.1 were tested at two points a year in Huanggang and Shandong Province. The random block design was designed and seeded three times per point, and the qPH3.2.1 was located between the marker Y72-Y91. Then, using the five recombination types screened in the target region of Y72-Y91, the F2 population constructed by single self-crossing was exchanged for progeny test to locate the Q-PH3.2.1 within the range of approximately 7.6Mb between the labeled YH305-Y72. 3. Fine positioning of qPH3.2.2. The crossing line pure lines (2125 strains) in the target region of qPH3.2.2 were tested at two points a year in Huanggang and Shandong Province. The random block design was designed and seeded three times per point, and the qPH3.2.2 was located between the marker P17-Y150. Then, using the four recombination types screened in the target region of P17-Y150, the F2 population was constructed by using different types of exchange single-plant self-crossing to carry out further fine mapping of qPH3.2.2 in progeny test. Finally, the qPH3.2.2 was located within the 8Mb range of the marker YH112-Y150. 4. The residual heterozygous population was used to relocate the qPH3.3. The segregation population was constructed by self-crossing of three residual heterozygotes containing the target region, and the qPH3.3 was repositioned by the method of compound interval mapping and single marker analysis. The accuracy and authenticity of the initial localization results were verified. 5, qPH 3.3 fine localization was carried out. According to the results of repositioning, 11 recombination types were screened in the target interval. The F2 population with different recombination types was used to map the qPH3.3 to the 11Mb range between the marker C79-C90.
【学位授予单位】：华中农业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S513

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