Evaluation of genetic diversity of Brassica napus germplasm from China and Europe assessed by RAPD markers

The genetic diversity and the relationships among rapeseed germplasm, including a collection of 20 Chinese, 25 Czech, 2 German, 2 French, and I English cultivars and breeding materials were evaluated using random amplified polymorphic DNA (RAPD) markers. A total of 79 different polymorphic amplification products were obtained using10 selected decamer primers. RAPDs revealed a significant level of polymorphism among the accessions. The diversity index (DI) ranged from 1.390 to 3,491, showing a sufficient potential of selected primers to differentiate among studied genotypes. Three different metrics were used to assess genetic diversity. The best fit between a priori knowledge about germplasm origin and a posteriori grouping was found using Hamman metrics. Cluster analysis based on Hamman pairwise distance comparison divided the studied accessions into three main clusters. The first group included only accessions from China, the second group only that from Europe with the exception of Zhongshuang No. 2, a Chinese winter rape possessing European cultivars in the pedigree. The third group included accessions both from China and Europe. The results indicate the occurrence of a considerable genetic variation between Chinese and European accessions.