Abstract: Relationship among 5 wild species and 26 cultivars were analyzed using RAPD（Random amplified polymorphic DNA）markers. One hundred and fifty three amplified fragments were detected by applying 17 10-mer primers, among them 149 fragments were polymorphic. Cluster analysis was then performed by UPGMA method. In the dendrogram based on the genetic similarity coefficients, Paeonia anomala were separated from other 30 samples at GSC(Genetic Similarity Coefficient) of 0.32; And at GSC of 0.54, P.veitchii, P.obovata and P.mairei were individually separated, while P.lactiflora was still linked together with all of the cultivars. The result suggested high genetic homogeneity between the cultivars and P.lactiflora. Comparatively, the other 4 wild species showed distant genetic relationship with the cultivars, and the order based on the GSC from close to distant was arranged as P.mairei, P.obovata,P.veitchii and P.anomola. This molecular study revealed the narrow genetic background of the cultivated peonies native to China, so there exists broad space of improving the cultivars with wild species. 

Key words: Peony, Germplasm resource, Relationship, RAPD