【作者】 冯彦侠；

【导师】 陈建民；

【作者基本信息】 扬州大学 ， 遗传学， 2010， 硕士

【摘要】 水稻杂种优势的利用是提高水稻产量的有效途径,但是目前由于选用的杂交亲本的遗传关系较近,育成的新品种的产量没有较大的突破。分子标记辅助育种可以更有效地利用资源的遗传多样性,在分子水平上更精确地进行选择,从而培育出更高产的杂交水稻品种。本研究利用基于反转座子的分子标记技术对三组水稻品种进行品种鉴定与杂种优势的预测。研究结果如下:1、籼稻和粳稻亚种间的DNA序列的差异性利用6对引物对12份供试水稻材料进行PCR扩增,共扩增出173个条带,97个是多态性带,多态性水平56.1%;其中籼稻的多态性为32.1%,高于粳稻的多态性(24.3%)。根据遗传距离进行聚类,可以清楚地把籼粳分为两大类,并且籼稻差异性高于粳稻。这说明利用基于反转座子发展的分子标记能够准确地鉴定籼粳稻亚种间及品种间的的遗传差异。2、水稻杂种优势的预测利用5对引物对8个水稻亲本(4个母本和4个父本)以及由它们组配的12个杂交种进行分子指纹图谱数据分析,结果说明基于反转座子发展的分子标记能很好地把这20份水稻材料区分开来。利用类平均聚类法(UPGMA)进行聚类分析,并对聚类后的遗传距离与产量相关的各农艺性状的关系进行分析,结果表明随着遗传距离的增大杂种优势越明显。各农艺性状的杂种表现和配合力方差分析表明,绝大多数性状的一般配合力方差大于特殊配合力方差,表明各性状在杂交组合的遗传效应中以加性基因效应为主;另外,超亲优势较高的组合中至少有一个亲本的一般配合力较高,说明亲本的遗传因素对子代表型有很大影响。遗传距离与各性状的回归相关关系表明,遗传距离与各性状之间大都呈正相关,但其决定系数并不高。3、偏籼偏粳稻的鉴定利用5对引物对53份偏籼偏粳水稻材料进行多态性分析,平均多态性56.5%,说明偏籼偏粳间存在较大的遗传多样性。聚类分析可将偏籼和偏粳分为明显的两大类,并且由相同亲本组配的杂交后代的亲缘关系更近,说明利用基于反转座子的分子指纹不仅可以区分出偏籼偏粳材料间的差异,而且可以显示出材料的遗传特征。更多还原

【Abstract】 The utility of heterosis is an effieient way to improve yield in rice.At present, the current result of the selection of hybrid parents are the close kinship so the production of new varieties bred have no major breakthrough in yield.The molecular marker assisted breeding is an effieient way for making full use of genetic diversity,fine seletion at molecular level,which leads develop rice hybrids for rice production and peaple’s demands. In this study, species identification and prediction of heterosis about three groups of rice by retrotransposon-based molecular marker techniques. The results were as follows:1.Subspecies differences in DNA sequences between Indica and japonicaA total of 173 bands were amplified by 6 primers in the PCR analysis with 12 indica and japonica, of which 97 are polymorphic, polymorphism level is 56.1%; Polymorphism of indica rice 32.1%, higher than the polymorphism of japonica rice(24.3%). Based on the genetic distance clustering can be clearly divided into two categories-Indica and Japonica,and the Indica polymorphism higher than the japonica rice. This shows that the use of retrotransposon-based molecular markers can accurately identify subspecies and varieties of genetic differences between the Indica and Japonica.2. Prediction of Heterosis in RiceThe eight rice parents( in which four female parents and four paternal), as well as their 12 hybrids can be well distinguished from rice materials with 5 pairs of primers of molecular fingerprinting datas. Using UPGMA method gets the dendrogram which based on the genetic distance.Analyse the correlation analysis between genetic distance and yield of agronomic traits. Agronomic traits of hybrid performance and parental combining ability analysis showed that among the vast majority of traits general combining ability variance is greater than specific combining ability variance. Therefore,the genetic effects get first place to the additive genetic effects in hybrid combinations of each trait.In the combination of ultra-high-parent heterosis, one parent have a high general combining ability, at least. The genetic factors that explain relatively large impact on the sub-representative type. Simple linear regressio relationship between genetic distance and various agronomic traits show that most of them are positive correlation. However, the coefficient of determination is not high.3. Identification of partial indica-japonica rice sideThe average polymorphism is 56.5% for 53 kinds of partial indica-japonica rice side with 5 pairs of primers show that there is a great genetic diversity between the partial indica and japonica side. Cluster analysis showed that partial indica and japonica is divided into two categories obviously. And by the same parents of the hybrids in this group with closer genetic relationship. These results suggest that the use of retrotransposon-based molecular fingerprints can distinguish not only the partial indica-japonica materials’differences and can show the genetic characteristics of these rice materials.更多还原