Analysis of cytoplasmic organellar function in wheat and its related species

1.普通小麦核质杂种与普通小麦及其近缘种细胞质杂种的光合能力和呼吸特性存在较大变异。杂种光合能力差异大于30%，光合能力差异大的同时伴随着不亲和性，导致杂种植株活力下降。细胞色素途径、细胞色素c氧化酶和交替途径活性在杂种间差异显著。细胞色素c氧化酶活性在细胞质缺失的杂种中显着升高，导致生长势下降.两种冰草的细胞核减数分裂与普通小麦细胞核结合后，其生长势和雄性育性明显下降，而端部着丝粒染色体则恢复了正常的生长势和雄性育性。冰草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，普通小麦与两种冰草的细胞质基因组间的遗传距离与普通小麦与簇毛麦的细胞质基因组间的遗传距离基本相同。两种冰草的细胞质基因组差异显著.构建了两种冰草和簇毛麦的叶绿体DNA物理图谱，并对光合作用相关基因进行了定位。

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.