Boonruangrod R, Desai D, Fluch S, Berenyi M, Burg K
Department of Bioresources, Austrian Research Centers GmbH, ARC, 2444, Seibersdorf, Austria.
Theor Appl Genet. 2008 Dec;118(1):43-55. doi: 10.1007/s00122-008-0875-3. Epub 2008 Sep 2.
Cytoplasmically inherited characters such as resistance to viral and fungal diseases, determination of starch types, crop yield, resistance to low or high temperature often contribute to the advantageous phenotypic traits of plants. In the present study, our goal was to elucidate the genealogy of cytoplasmic genomes chloroplast and mitochondria in banana. Banana breeding is rather complicated because of the low fertility and mostly unknown origin of the edible cultivars, therefore, knowledge on the putative fertile ancestors of cytoplasmic genomes chloroplast and mitochondria would be beneficial for breeding programmes. Based on the established marker systems distinct species specific gene-pools could be identified for both chloroplast and mitochondrial genomes for Musa acuminata and Musa balbisiana wild types, respectively. Detailed analysis of the species specific chloroplast and mitochondrial gene-pools of M. acuminata and M. balbisiana revealed six chloroplast and seven mitochondrial gene-pools in the analysed accessions. Comparative analysis of the haplotypes revealed the presence of Primary Centers of origin for both chloroplast and mitochondrial genomes of both species supporting the idea of common origin of these genomes. Cytotypes representing combinations of M. acuminata chloroplast and mitochondrial gene-pools were identified in majority of the analysed hybrid cultivars. A single M. acuminata cytotype was present in the majority of the analysed cultivars, which combination was not detected in any of the wild types. On the other part a single balbisiana cytotype was identified participating in the formation of interspecies hybrids. The strong preference for the presence of certain cytoplasmic gene-pools in cultivars may indicate hundreds of years of natural as well as of farmers' selection supplementing the phenotypic traits provided by the nuclear genome. Based on the present results the present day subspecies classification of M. acuminata is also discussed.
细胞质遗传性状，如对病毒和真菌病害的抗性、淀粉类型的决定、作物产量、对低温或高温的抗性等，常常有助于植物表现出有利的表型特征。在本研究中，我们的目标是阐明香蕉叶绿体和线粒体细胞质基因组的谱系。由于可食用品种的育性低且起源大多未知，香蕉育种相当复杂，因此，了解叶绿体和线粒体细胞质基因组可能的可育祖先，将对育种计划有益。基于已建立的标记系统，分别为尖叶蕉和野蕉野生型的叶绿体和线粒体基因组鉴定出了不同的物种特异性基因库。对尖叶蕉和野蕉物种特异性叶绿体和线粒体基因库的详细分析显示，在所分析的种质中存在6种叶绿体基因库和7种线粒体基因库。单倍型的比较分析表明，这两个物种的叶绿体和线粒体基因组都存在主要起源中心，支持了这些基因组有共同起源的观点。在大多数分析的杂交品种中，鉴定出了代表尖叶蕉叶绿体和线粒体基因库组合的细胞型。在大多数分析的品种中存在单一的尖叶蕉细胞型组合，而在任何野生型中都未检测到这种组合。另一方面，鉴定出了单一的野蕉细胞型参与种间杂种的形成。品种中对某些细胞质基因库存在的强烈偏好，可能表明经过数百年的自然选择以及农民选择，补充了核基因组提供的表型特征。基于目前的结果，还讨论了尖叶蕉当今的亚种分类。
