Molecular studies on cytoplasmic variation in three major crops and their related species and its utilization in the breeding

本合作研究旨在通过各种分子技术阐明水稻、小麦和甜菜及其野生近缘种的细胞质变异，并利用这些变异进行这些作物的育种。1）细胞器DNA的限制性内切酶分析和物理图谱的构建：构建了日本水稻、普通小麦和甜菜的叶绿体（ct）DNA的详细物理图谱。限制性内切酶分析进行了大量的加入二倍体稻属物种，所有小麦和山羊草属物种，和11个Beta物种。2）细胞器DNA文库的构建：构建了水稻、小麦和甜菜的叶绿体DNA文库。3）小环线粒体DNA的研究：从小麦线粒体DNA中克隆了两个小环DNA，B- 关于我们 1和B-2的基因片段，并分别进行了部分和全序列测定。这些DNA种类从雄性可育回复突变体的线粒体中消失。在10份甜菜雄性可育或不育材料的不同组合中，存在8种不同分子类型的小环状DNA。4）叶绿体基因分析：在水稻、普通小麦和甜菜的物理图谱上，分别定位了10 ~ 18个叶绿体基因。测定了水稻rbcL、atpB、aptE和psbA基因以及小麦和三种山羊草属植物rbcL基因的全序列。5）水稻mtDNA ars区的克隆和序列测定：从水稻mtDNA中分离到两个具有ars活性的序列，并进行了序列测定。6）外源细胞质染色体导入作物的遗传特性：O. sativa细胞质转入O. glaberrima，并产生雄性不育系。在从O.普通猪毛菜AE. searsii是两个四倍体物种Ae. kotschyi和Ae.变量一些异质小麦品系表现出与正常小麦品系不同的光合和/或电子传递活性。kotschyi细胞质比用t. timopheevi。细胞质一个普通的小麦生产线在高频率的双苗也产生使用Ae。kotschyi细胞质。少

The present cooperative research aimed to clarify cytoplasmic variation in rice, wheat and sugar beet, including their wild relatives, by various molecular techniques, and to utilize the variation in breeding of these crops. The research was conducted on the following seven items:1) Restriction endonuclease analysis and construction of the physical map of organellar DNAs: Detailed physical map of chloroplast (ct) DNA was conctructed in Japanese rice, common wheat and sugar beet. Restriction endonuclease analysis was carried out using a large number of accessions of diploid Oryza species, all Triticum and Aegilops species, and 11 Beta species. From the results, a phylogenetic tree of the chloroplast genome was constructed for each genus.2) Construction of the organellar DNA library: CtDNA library was constructed in rice, common wheat and sugar beet. About 70% of the HindIII fragments of wheat mitochondrial (mt) DNA were cloned.3) Studies on small circle mtDNAs: Two small circle DNAs, B- … More 1 and B-2, in mitochondria of male sterile rice were cloned, and partially or completely sequenced, respectively. These DNA species disappeared from mitochondria of the male fertile revertants. Eight different molecular species of small circle DNA were present in different combinations in ten male fertile or sterile accessions of sugar beet.4) Analysis on chloroplast genes: Ten to 18 chloroplast genes were located inthe physical map of each rice, common wheat and sugar beet. Complete nucleotide sequence of the genes, rbcL, atpB, aptE and psbA of rice, and rbcL genes of common wheat and three Aegilops species was determined.5) Cloning and sequencing the ars regions of mtDNA: Two sequences having the ars activity were isolated from rice mtDNA,and sequenced. They had the characteristic structures of the ars region.6) Genetic characterization of alien cytoplasms introduced into crop species: O. sativa cytoplasm was transferred into O. glaberrima, and the male sterile line was produced. Four new male sterile cytoplasms were identified among those introduced from O. rufipogon. Ae. searsii was found to be the cytoplasm donor to two tetraploid species, Ae. kotschyi and Ae. variabilis. Some alloplasmic wheat lines showed different photosynthetic and/or electron transport activities from the normal wheat line.7) Use of alien cytoplasms: Triple cross whear hybrids produced using Ae. kotschyi cytoplasm were more productive than the F_1 hybrids produced using t. timopheevi. cytoplasm. A common wheat line yielding twin seedlings at a high frequency was also produced using Ae. kotschyi cytoplasm. Less