【作者】 孙峰成；

【导师】 于卓； 冯勇；

【作者基本信息】 内蒙古农业大学 ， 作物遗传育种， 2012， 博士

【摘要】 玉米群体的遗传基础广泛,分析和掌握其来源、系谱关系及遗传差异,并据此将其合理地划分为不同的杂优类群,建立杂种优势模式,对于避免杂交种组配的盲目性、提高育种效率至关重要。为提高玉米人工合成群体的改良利用效率,本研究以蒙群1、蒙群2、蒙群3、蒙群4、蒙A群、蒙B群、蒙C群7个自有群体,中综5号、中综7号2个国内合成的群体,以及3个加拿大引进群体C群1、C群2、C群3为供试材料,B73、Mo17、丹340、黄早4、掖4785个自交系为测验种,通过田间鉴定和分子水平检测,对其表型性状、配合力、杂种优势、增密效应等方面进行分析,旨在划分杂种优势群,确定高效杂种优势利用模式,鉴别和筛选出利用前景广、育种潜力大的优良群体,为玉米种质创新与杂交改良利用提供科学依据。主要结果如下：1.灰色关联度分析发现,12个玉米群体与产量密切相关的农艺性状依次是出籽率、行粒数、穗粗、百粒重、株高、穗粒数、穗长、穗行数、穗位高和秃尖长度,与粗蛋白、粗脂肪、粗淀粉和赖氨酸含量等营养品质密切相关的农艺性状依次是穗粒数、百粒重、行粒数、出籽率、穗行数、株高、穗粗、穗位高、穗长与秃尖长度。2.12个玉米群体在内蒙古东部、中部、西部三种不同环境条件下的15个农艺性状GCA效应分析表明,蒙C群、蒙群3、蒙群4、中综7号4个群体产量潜力高,主要农艺性状优良,是选育自交系和培育杂交种的理想材料,可优先考虑作为育种材料直接利用。产量SCA效应分析表明,除C群2外,其余11个群体划分成4个杂优类群。3.在12个群体与测验种测交的60个杂交组合中,中综7号×掖478、蒙A群×Mo17、蒙B群×B73、蒙C群×B73、蒙群4xB73、C群1×黄早4、C群2×黄早4、中综5号×B73这8个组合的SCA值均较高,它们之间的遗传差异大,优良非加性基因频率高,具有潜在杂种优势模式和强杂种优势,可用于构建杂种优势模式。4.综合产量与抗性指标,玉米群体增密效应分析得出,蒙A群、蒙群4适宜增密种植,蒙群1、蒙B群、蒙C群、中综7号4个群体可适当增密,C群2、C群3、蒙群3、蒙群2、C群1、中综5号6个群体不适于增密。5.群体改良效果分析得知,蒙群2、蒙群4、中综7号、蒙C群、蒙A群产量遗传增益均较大,并在其它农艺性状中改良效果显著,可直接选择优株自交进行选系,而其余7个群体遗传增益小,改良利用潜力不大。6.玉米群体DNA取样试验确定出,每个群体60株、每12株叶片混合提取DNA,组成5个样本,为玉米群体DNA的最优取样方法。7.利用筛选出的86对SSR适宜引物,对12个玉米群体及6个对照自交系的基因组DNA扩增得到391条多态性带,每个位点上的等位基因数为2-11之间,平均5.67条,各群体间的GD值在0.268-0.807之间,平均为0.528,群体遗传基础较宽。以GD值0.67为基准,将12个群体及6个对照自交系划分为6个类群。更多还原

【Abstract】 It is very important to partition heterotic group and build up heterotic patterns based on the analysis of the originality, the genealogical relationship and the generic difference of the maize generic characters for avoiding the blindness of hybrid and improving the efficiency of breeding, as the generic basis of maize group is very wide. In this study, we aimed at (1) improving the improvement efficiency of artificially synthesized maize populations and (2) providing scientific basis for maize germplasm innovation and hybrid improvement through partitioning heterotic populations, determining heterotic improvement patterns, and filtering the top quality populations with wide improvement prospect and high breeding potential. The phenotypic character, combining ability, hetarosis, densification effect, etc aspects of12maize populations, including7self-breeding maize populations, MengQunl to MengQun4, MengAQun, MengBQun, MengCQun,2internal maize populations, Zhongzong5and Zhongzong7, and3Canada populations, CQunl to CQun3, were analyzed by field identification and molecular level detection. The inbred line B73、Mo17、Dan340、Huangzao、Ye478were the tested varieties. The main results were listed below.1. Based on grey relativity analysis, the most closed interrelated agricultural characters of these12populations associated with maize yield is seed rate, followed by kernels per row, spike diameter,100-seed weight, plant height, number of grains per spike, spike length, number of rows per spike、ear height and the length of the bald; the order of agricultural characters, which is closed associated with content of crude protein, crude fat, crude starch, and lysine, etc nutrient quality, is number of grains per spike,100-seed weight、number of grains per row, seed rate, number of rows per spike, plant height, spike diameter, ear height, length of spike and the length of the bald.2. In the GCA effect analysis on15agricultural characters of these12maize populations in the eastern, western and central area of Inner Mongolia, the increasing potential yield of MengCQun, MengQun3, MengQun4and Zhongzong7is the highest, and the main agricultural characters of these four populations are better than the other study populations. Therefore, these four populations are the ideal material for selecting selfed lines and breeding hybrids, and able to use as the breeding material. Base on the SCA analysis, these12maize populations were partitioned into4hetarosis class populations, and only CQun2is belong to different hetarosis class group in these three areas.3.60hybrid populations were generated by test cross between these12maize populations and tested varieties. The higher values of SCA showed in the populations of Zhongzong7x Ye478, MengAQun x Mo17, MengBQun x B73, MengCQun*B73, MengQun4x B73, CQun x Huangzao4, CQun2x Huangzao4and Zhongzong5x B73. As the higher generic difference and frequency of good non-additive gene are showed in these8populations, they have the advantage to build up hetarosis pattern.4. The results in the maize densification effect analysis showed that the planting density of MengAQun and MengQun4were suitable to be densified; MengQunl, MengQun, MengQun and Zhongzong7were able to be densified, but CQuanl, CQuan2, CQuan3, MengQun2, MengQun3and Zhongzong5were not suitable to be densified.5. The generic increment in yield is higher in the populations of MengQun2, MengQun4, Zhongzong7, MengAQun and MengCQun, furthermore, the improvement effect of the other agricultural characters were also significant. Thus, these five maize populations have the advantage in directly selecting first-class plants for self cross. The generic increment of the other seven populations was small, and the potential improvement of these populations was very limited.6. The results in the investigation of DNA sampling from maize populations indicated that the best DNA sampling method was to sample60-plants from each maize group, and divide five sub-populations with12-plants per sub-group, then extract DNA sample from mixing leaves in each sub-group.7.391polymorphic bands were gained by amplifying genome DNA from the studied12maize populations and6CK self cross maize populations using86selected primers. There are2-11genes in each locus, average is5.67. The value of GD of these18maize populations is ranged from0.268to0.807with0.528for the average, thus, the hereditary basis of maize populations is wide. The studied12maize populations and6CK self cross maize populations could be partitioned into6class group on the basis of0.67for the GD value.更多还原