中国白菜型油菜种质资源的遗传多样性研究

Genetic Diversity of Germplasm Resources of Brassica campestris L. in China by RAPD Markers

利用 RAPD标记和 UPGMA聚类分析 ,对我国 2 3个省市的 172份白菜型油菜资源进行了遗传多样性分析。 4 3个随机引物扩增出 2 4 8条多态性带。聚类分析表明 ,我国白菜型油菜分为 15个类群 ,其中 ,6个类群为北方小油菜 ,8个类群为南方油白菜 ,及 1个混合类群。我国白菜型油菜的遗传多样性是非常丰富的 ;北方小油菜品种之间的遗传差异很大 ,春油菜的遗传多样性水平明显高于冬油菜 ;南方油白菜的遗传变异类型很多 ,而南方小白菜与其它类型的白菜型油菜关系密切。北方小油菜的遗传多样性与地理分布密切相关 ,而南方油白菜与地理分布具有一定的相关。在北方小油菜中 ,来自青海、甘肃和新疆的地方品种的遗传变异较大 ,比其它地方品种表现出更高的遗传多样性水平 ;而在南方油白菜中 ,来自云南、贵州和湖北省的地方品种的变异类型较多 。

RAPDs (Randomly Amplified Polymorphic DNAs) were used to research the genetic diversity among 172 landraces of Brassica campestris selected from all of China. Forty three random 10 mer primers were tested and 248 polymorphic bands were amplified. By using the dendrogram analysis, 172 varieties were separated into two major groups at the DNA level: 8 vegetable campestris and 164 oil purpose campestris. This result was corresponded to morphological classification and previous conclusions. Vegetable B.campestris was very different from oil purpose B.campestris. Moreover by UPGMA (Un weighted Pair Group Mathematics Average) clustering, the germplasms of 164 oil purpose B. campestris were separated into 15 groups: 6 groups from northern origins, 8 groups are southern origins and one mixed group. The result indicated that the group dividing was related to geographical origins. The diversity level of spring type is higher than that of winter type. The genetic diversity of northern B. campestris was related closely to geographical regions. Spring type campestris was closer to winter type campestris than to semi winter type campestris in genetic relationships and had more extensive difference in genetic diversity than winter type campestris. Semi winter type campestris had a great many genetic variations and its genetic diversity level was also related to geographical origins. Furthermore, landraces from a specific area such as Yunnan Guizhou Hubei provinces and Qinghai Gansu Xinjiang Provinces show more genetic variations and exhibited higher level of genetic diversity than landraces from other provinces, which might give some evidences about origins of B. campestris, as China is the origin center of B. campestris L.