【作者】 孙朝辉；

【导师】 陈彦惠；

【作者基本信息】 河南农业大学 ， 作物遗传育种， 2009， 硕士

【摘要】 光周期是影响植物生长发育的关键环境因素之一。玉米是短日照植物,光周期敏感性是不同纬度和不同海拔地区间玉米种质资源交流的主要限制因子。研究热带玉米的光周期反应的分子机理,弱化玉米的光周期敏感性,不但有利于玉米种质的扩增与创新、提高玉米品种对不同地理纬度和播种季节的适应性,而且还能在玉米开花时间的光周期调控方面进行有益的探索。本研究以对光周期钝感的温带自交系黄早4和对光周期敏感的热带自交系CML288为亲本配置了温热组合黄早4×CML288,通过单粒传法构建了一套重组自交系群体(RIL)。2006年在河南郑州长日照环境下对包含207个家系的F7代RIL的群体进行了田间鉴定,考察了光周期敏感相关性状株高和叶片数的动态发育状况,结合构建的遗传连锁图谱,对考察的性状进行了发育动态的QTL定位分析。2007年在河南郑州、河南洛阳和北京昌平3个地点2个不同的光周期环境下,对包含201个家系的F10代RIL群体及包含278个杂交组合的永久F2群体进行了田间鉴定,考察了总气生根层数和有效气生根层数等光周期敏感性相关的性状,结合构建的遗传连锁图谱进行了QTL定位、遗传效应以及与环境互作效应的分析,主要结果如下:1、选用玉米基因组的713对SSR引物对亲本进行多态性筛选,以F7代和F10代重组近交系为基础材料,构建了两个包含237个SSR标记的重组近交系遗传连锁图,总长度分别为1753.6与1974.7cM,平均间距分别为7.40与8.33cM。两张图谱有很好的一致性,与IBM群体连锁图谱相比在图谱总长度、分子标记总数和平均间距均仍有一定差距,但共同SSR标记在连锁图谱位置非常一致。2、利用F7代重组自交系群体,在郑州环境下共检测到20个不同的控制株高发育的QTL,分布在除第2染色体外的所有9条染色体上,其中非条件QTL 11个,条件QTL 16个。检测到11个不同的与叶片数有关的QTL,分别位于第1、2、4、7、8、9和第10染色体上,其中非条件QTL 8个,条件QTL 6。株高和叶片数的QTL在不同时期的表达是不一样的,有些QTL在连续的几个时期都被检测到,有些QTL只能在特定时期检测到。没有一个QTL能在测定的所有时期都有效应,说明可能没有一个基因能在玉米生长的所有阶段都表达。3、F10代RIL群体和永久F2群体田间试验结果表明,总气生根层数和有效气生根层数方差分析的F值均达到极显著水平;群体性状分布的偏斜度、峰度绝对值均小于1,符合正态分布,且均有较大的变异幅度,呈现数量性状的遗传特点。结果还表明,总气生根层数和有效气生根层数两个性状均受加性和显性基因效应的共同作用,在总气生根层数上黄早4对CML288表现部分显性效应,而在有效气生根层数上CML288对黄早四表现部分显性效应。总气生根层数与有效气生根层数间均呈极显著的表型相关和遗传相关。总气生根层数的广义遗传力较高。4、利用RIL群体共检测到6个控制总气生根层数的QTL和4个控制有效气生根层数的QTL。控制总气生根层数的QTL分别位于玉米的第1,5,6,7,9,10条染色体上。控制有效气生根层数的QTL分别位于玉米的第3,5,9和第10条染色体上,加性效应绝对值和贡献率都不大。利用IF2群体共检测到8个控制总气生根层数的QTL和7个控制有效气生根层数的QTL。控制总气生根层数的QTL分别位于玉米的第1,2,5,7,8,10条染色体上,其中3个具有显著的显性效应。检测到7个控制有效气生根层数QTL,分别位于玉米的第5,6,8,9和第10条染色体上。5、两个群体在3个地点(两个不同的光周期环境)共检测到2个相同的总气生根层数QTL和1个相同的有效气生根层数QTL。控制总气生根层数的QTL分别为位于第7染色体umc1426-umc1159区间的的qTAR7-1和位于第10染色体umc1873-umc1077的qTAR10-1,其中qTAR10-1为主效QTL,可解释17.88 %的表型变量。控制有效跟层数的QTL为位于第10染色体umc1873-umc1077的qEAR10-1,也是主效QTL,可解释6.37%的表型变量。在两个群体中都检测到多对上位性互作QTL,且所解释的表型变异占一定比例,表明上位性效应在气生根的遗传中大量存在,尤以永久F2群体居多。绝大多数QTL及上位性与环境间均无显著的互作效应,仅在IF2群体中检测到作用效应极小的3个QTL与环境互作。6、综合上述试验结果表明,株高和叶片数的动态发育QTL定位以及总气生根层数和有效气生根层数均在第10染色体的umc1873附近检测到主效QTL,表现为一因多效或基因紧密连锁,说明该位点附近可能含有控制光周期敏感的主要基因,该实验也可为其进一步精细定位等研究奠定基础。更多还原

【Abstract】 Photoperiod is a major environment factor affecting plant development. Maize is short day plant and flowering time is affected by photoperiod. Sensitivity to photoperiod limits the potential for successful exchange of germplasm across different latitudes. Therefore, it is vital for maize breeders to understand the genetic basis of photoperiod sensitivity in their efforts to integrate tropical germplasm into temperate zone maize breeding.For resolving the genetic basis of photoperiod sensitivity in maize, in this research , a population of 207 recombinant inbred lines (F7) derived from a temperate and tropical inbred line cross were developed . In zhengzhou location of 2006, we detected the plant height and leaf numbers the two photoperiod relevant senstivity traits in different development periods, combining with the genetic linkage map, we detected the conditional QTLs and unconditional QTLs. In the base of F7 recombinant inbred lines ,we constrcted a F10 recombinant inbred lines, and an immortalized F2 population of 278 F1 cross which was constrcted by intercrossing of RIL population. The immortalized F2 population and the RIL population were evaluated in three location of two different photoperiod environment in 2007. Total aerial root numbers and effective aerial root numbers, the performinance data of the two photoperiod sensitivity relevant traits in RIL population and immortalized F2 popultion were used for QTL mapping and digenic interaction analysis. The main results obtained in this study were concluded as follow:1. Two genetic linkage maps, both containing 237 SSR polymorphic markers was constructed using F7 and F10 RIL populations, spanned a total length of 1753.6 and 1974.3 cM with an average space between two makers of 7.40 and 8.33 cM, respectively.2、In zhengzhou location, using the F7 RIL popution, 20 plant heigth QTLs were detected, distributing in the 9 chromosomes except the No. 2 chromosome, including 11 unconditional QTLs and 16 conditional QTLs ;11 leaf number QTLs were detected, distributing in the 1、2、4、7、8、9 and the 10 chromosomes ,including 8 unconditional QTLs and 6 conditional QTLs. In different stages, the expression of the plant numbers and the leaf numbers were different, some of them can be detected in several continuous times, while some others could be detected only in specific stages. None QTL can be detected in all the stages, it showed that none QTL can express in all the stages.3、In the three locations of two different photoperiod , the Total aerial root numbers and Effective aerial root numbers in the RIL (F10) and IF2 poputions both have significant differences, the frequency of all traits show continuous changes and normally distribution,so the two population can be used in QTL mapping and analysis. The conclusion also showed that the total aerial root numbers and the effective aerial root numbers were synergy effected by the additive effect and the dominant effect. The Total aerial root numbers and effective aerial root numbers was registered as phenotypic correlation and genotype correlation, the broad-sense heritability of the total aerial root numbers was higher than the effective aerial root numbers.4、6 QTLs that controlling total aerial root and 4 QTLs that controlling effective aerial root were detected in the F10 RIL, they were located in the 1,5,6,7,9,10 chromosomes and 3,5,9,10 chromosomes, respectively. The additive effect absolute value and the contribute value of all the QTLs that contriolling the effective aerial roots were low. 8 QTL that controlling total aerial root and 7 QTL that controlling effective aerial root were detected in the IF2 popution, they were located in the 1,2,5,7,8,10 chromosomes with 3 dominant effect and 5,6,8,9,10 chromosomes, respectively.5、Two similar total aerial root numbers QTLs and one sililar effective aerial root numbers were detected in the RIL(F10) and IF2 poputions in three different locations. The QTLs that controlling the total aerial root numbers were qTAR7-1 and qTAR10-1, located in umc1426-umc1159 segment of chr.7 and umc1873-umc1077 of chr.10, respectively. qTAR10-1 was the main effect QTL, can explained phenotypic variation 17.88%. qEAR10-1, the main effect QTL that controlling the effective aerial root numbers, also located in umc1873-umc1077 of chr.10, can explained phenotypic variation 6.37%. Using QTLNetwork2.0 software, epistasis was detected in the F10 RIL and IF2 poputions, they can explain some of the phenotype variations. It shows that the epistasis was abound exist in the heredity of the aerial roots, much more in the IF2 poputions, especially. Most of the QTLs and epistasis, detected in the RIL(F10) and IF2 poputions, have no significient interactions with the environment. There are only 3 interactions between QTLs and environment in the IF2 popution, all of them have low effect.6、We conclude that a main effect photoperiod sensitive QTL that located in the umc1873 region of chromosome 10 were detected in all the triats in the 3 poputions,it shows pleiotropic or closely linked each other, it is the base for the fine mapping and breeding.更多还原