Abstract: The evaluation of distinctness, uniformity and stability is very important for new variety registration and protection. In this study, 89 varieties being subjected to National official field test were fingerprinted by 41 polymorphic markers generating from 15 highly informative SSR primers. The genetic clustering, principal component analysis, assignment test and AMOVA (analysis of molecular variance) results showed that: 41 polymorphic markers are sufficient to completely separate all 89 varieties; most similar varieties were bred by the same breeders and the most distinct ones came from different province or breeders, which was in accordance with the pedigree information; 75% of the tested varieties are distinct using a genetic distance threshold of 0.1; in the assignment test, most varieties can be correctly placed back to the respective source variety, yet the other had a low correct individual assignment percentage, a sign of poor uniformity; the genetic variation between seed delivery is not significant, indicating a good stability of variety, and genetic variation among varieties within seed delivery is significant, meaning a good distinctness. Overall, our data showed that most of the tested rapeseed varieties have the characteristics of distinctness, uniformity and stability (DUS), and SSR marker is suitable for DUS testing.

Key words: rapeseed (Brassica napus L.), official field test, SSR marker, DUS testing