Analysis of cytoplasmic organellar function in wheat and its related species

1. 普通小麦的核细胞质与普通小麦及其近缘种的细胞质在光合能力和呼吸特性上存在较大差异。杂种间的光合能力差异达30%以上，而较高的光合能力伴随着不亲和，导致杂种的植株活力降低。不同杂种间细胞色素途径、细胞色素c氧化酶和替代途径的活性差异显著。细胞色素c氧化酶活性在有细胞质的杂种中显著升高，导致生长活力降低。两种稻草的细胞质与普通小麦核结合后，其生长活力和雄性育性明显降低，而稻草的远心染色体则恢复正常的生长活力和雄性育性。Agropyron细胞质与普通小麦细胞核的不亲和性表现为线粒体功能异常。叶绿体和线粒体dna的研究表明，普通小麦与两种稻草的细胞质基因组之间的遗传距离与普通小麦与海纳尔迪亚的遗传距离几乎相同。两种稻的细胞质基因组差异显著。构建了两种稻草和海纳藻的叶绿体dna物理图谱，并在图谱上定位了光合作用相关基因。

1. A large variability was found in photosynthetic capacity and respiratory characteristics in nuclar cytoplasmic hybrids of common wheat with cytoplasms of common wheat and its related species. Photosynthetic capacity differed more than 30% among the hybrids, while higer capacity was accompanied by incompatibility, resulting in the reduction of plant vigor of the hydrids. The activities of cytochrome path, cytochrome c oxidase and alternative path differed significantly among the hybrids. The cytochrome c oxidase activity was markedly high in hybrids with cytoplasms causing the reduction of growth vigor.2. Cytoplasms of two Agropyron species caused marked reduction in growth vigor and male fertilitly when combined with common wheat nucleus, while Agropyron telocentric chromosmes restored normal growth vigor and male fertility. The incompatibility between Agropyron cytoplasms and common wheat nucleus was expressed as aberrant mitochondrial function.3. Study of chloroplast and mitochondrial DNAs showed that the genetic distances between cytoplasmic genomes of common wheat and the two Agropyron species were nearly the same as that between common wheat and Haynaldia villosa. The cytoplasmic genomes of the two Agropyron species differed significantly.4. Physical maps of chloroplast DNAs of the two Agropyron species and Haynaldia villosa were constructed and photosynthesis-related genes were located on the maps.