【作者】 何婷婷；

【导师】 谭学林；

【作者基本信息】 云南农业大学 ， 作物遗传育种， 2013， 博士

【摘要】 水稻是重要的粮食作物，也是分子生物学上的模式植物。育性恢复基因(restorer fertility gene,Rf)是细胞质雄性不育利用于杂交水稻所必需的关键基因。Rf-1是水稻上研究最系统的、也是第一个被克隆的恢复基因。恢复基因仅存在于热带、亚热带的野生稻和籼稻种质中，而不存在于温凉气候的粳稻种质中。研究Rf-1恢复基因在水稻种质中的变异以及海拔和细胞质因素对Rf-1位点基因型遗传分离比例的影响，不仅有助于对水稻恢复基因演化的认识，也有助于阐明恢复基因与适于不同海拔条件的籼粳亚种的分化的关系。本研究利用Rf-1位点上的特异性标记68923-8对来源不同的野生稻、籼稻和粳稻品种的PCR序列进行研究，以分析该恢复基因位点在水稻中的序列差异，从而进一步研究恢复基因的演化。另外，对不同细胞质背景的改良品种南34和C418分别与云南地方高寒品种的杂交组合在不同海拔的小穗育性及在Rf-1位点上的基因型频率进行研究，以分析高低海拔（2200m，1890m，1250m，400m）和细胞质对不同杂交组合Rf-1位点的遗传分化的影响。结果如下：（1）根据Rf-1位点的PCR片段序列间的遗传距离构建系统发育树，供试材料可分成两大类，第一类包括野生稻、籼稻种质及粳稻恢复系，第二类包括7个粳稻常规品种。在第一类中，又主要分成野生稻和籼稻两部分，但有一个籼稻常规品种滇黎401与野生稻的亲缘关系较近。（2）中高海拔下（1890m和2200m），具粳稻细胞质背景的亲本产生的杂交组合的小穗育性平均值大于具籼稻细胞质背景亲本产生的杂交组合的小穗育性，而在中低海拔（400m和1250m），小穗育性平均值在籼粳不同细胞质间出现差异。（3）在Rf-1位点上，以具籼稻细胞质背景的恢复系为母本时，各海拔点产生的分离群体均极显著的偏向具籼稻细胞质的亲本南34，且在中高海拔地区产生的分离群体的偏离程度更大；而具粳稻细胞质背景的亲本产生的杂交后代分离群体中，中高海拔较易发生偏分离，低海拔地区发生偏分离的群体较少，且所有海拔发生偏分离的群体绝大部分偏向地方品种。（4）粳稻细胞质背景下，在低海拔产生与在中高海拔产生的分离群体间的分化较为明显，而具籼稻细胞质背景的亲本产生的群体间的遗传分化在不同世代间存在差异。聚类分析也表明，籼、粳不同细胞质产生的分离群体间存在明显的遗传分化，而且籼稻细胞质下的分化受到海拔的影响更加显著。（5）本研究首次揭示了野生稻与籼、粳稻在Rf-1位点上的序列变异及其亲缘关系，该结果可以为籼粳进化等研究提供参考。另外，本研究首次揭示了籼稻细胞质与粳稻细胞核间的遗传互作不协调，以及海拔因素可使群体的Rf-1位点基因型遗传结构发生改变，最终导致群体出现遗传分化。更多还原

【Abstract】 Rice is one of the most important crops, and it is a model plant in molecular biology. Restorerfertility gene (Rf) is the key gene for cytoplasmic male sterility used in hybrid rice production. Rf-1isthe first one of Rf genes studied systemically and cloned. Rf genes exist only in wild rice and indica ricethat grow in tropical and subtropical region, but don’t exist in japonica rice germplasm fitting templateregions. Studies on sequence variation at Rf-1locus in rice germplasm and on genotype segregationdistortion at Rf-1locus caused by altitude and cytoplasmic factors would helpful for understandingevolution of Rf genes in rice, also helpful for clarifying relationship between Rf genes andindica-japonica differentiation of different altitude condition.Based on68923-8primer located on Rf-1locus, PCR fragment sequences in wild rice, indica andjaponica rice were analyzed and to indicated sequence variation in rice, further study evolution of Rfgene sequentially. Segregated populations generated from crosses between Nan34and C418possessedRf-1gene and Xiaohuagu and Xiaomagu possessed non-Rf-1gene, which are two japonica ricelandraces from a high altitude in Yunnan. Geneotype segregation at Rf-1locus of the populationsgenerated at four altitudes (400m、1250m、1890m and2200m) were analyzed by PCR with68923-8primer, also spikelet fertility of the populations were analyzed, to know the effect to geneticdifferentiation of altitude and cytoplasm The main results were as follows:（1）According to phylogeny tree based on DNA fragment sequence at Rf-1locus, all of thegermplasm were divided into two groups, one was consisted of wild rice, indica rice and japonicarestorer lines, and the another one constituted mainly by japonica conventional varieties. The first groupwas consisted mainly by wild and indica lines, and only one indica conventional variety namedDianli401had near relationship with wild rice.(2) Sikelet fertility average value under japonica cytoplasm was larger than indica cytoplasm atmiddle、high altitudes（1890m and2200m）, but at low、middle altitudes（1250m and1890m）, spikeletfertility average value between reciprocal populations distorted to different cytoplasm.(3) On Rf-1locus, as Nan34which has indica cytoplasm was female parent, populations were alldistorted toward Nan34at all altitudes, and the distorted was more serious at middle、high altitude.Under japonica cytoplasm background, only several populations occurred distortion, and thosepopulations was most distorted toward landrice.(4) Under japonica cytoplasm background, differentiation between low altitude and middle-highaltitude was significated, and populations of different generations had difference under indica cytoplasm.Cluster analysis indicated that there were obvious differentiation between indica and japonica cytoplasm,and indica cytoplasm effects on differentiation were modified by altitude variation.(5) Our study first indicate sequence variation on Rf-1locus of different type of rice, and these results could be reference for study indica-japonica differentiation. In addition, it is the first time toshow that genetic structure of populations would be changed by effects from interaction betweenindica-cytoplasm and japonica-nuclei, and then caused genetic differentiation between populations.更多还原