中国西藏芥菜型油菜遗传多样性研究

利用8对SRAP (sequence－related amplified polymorphism) 引物，结合20个表型性状对73份中国西藏及35份包含中国西南地区、西北地区和印度的芥菜型油菜进行了遗传多样性分析。8对SRAP引物共扩增出139个带谱，34个多态性条带，多态性带的比例为24.5%；SRAP分子标记结果的聚类分析将材料分为4个大类，材料按地区聚集现象明显；中国西藏地区材料的遗传多样性指数最高。对西藏材料的8个重要表型性状的变异程度分析显示，变异系数最高的性状为全株角果数，达41.29%。表型性状聚类结果表明除中国西北材料外，其它材料按地区聚集现象明显。综合分子标记和表型性状分析结果表明，中国西藏芥菜型油菜具有丰富的遗传多样性，其程度与地理环境和气候条件有十分重要的关系。不同地区芥菜型油菜遗传多样性程度从大到小依次为：中国西藏、中国西南地区、中国西北地区、印度。  

Genetic diversity of Brassica juncea from Tibet Autonomous Region of China

Genetic diversity of 73 mustard (Brassica juncea L.) accessions from Tibet Autonomous Region of China and 35 from southwest of China，northwest of China and India were analyzed using 8 SRAP (sequence－related amplified polymorphism) primers combinations on 20 phenotypic traits. SRAP results showed that a total of 139 bands were produced with polymorphism rate of 24.5%. Clustering result of SRAP showed that 108 accessions were divided into 4 groups, and the accessions in each group were mainly from the same region. Genetic diversity index of China Tibet accessions was higher than others. Variation degree of 8 important phenotypic traits of Tibet accessions showed the highest variation coefficiency was 41.29% on silique number per plant. Clustering analysis of phenotypic traits showed that 108 materials were clearly divided into different groups based on their original regions except the accessions from Northwest. In conclusion, Tibet mustard had abundant genetic diversity. The order of genetic diversity indexes from top to bottom was as follows: China Tibet, Southwestern China, Northwestern China and India. Mustard genetic diversity was mainly associated with geological and biological conditions.