Genetic diversity assessment of chrysanthemum germplasm using conserved DNA-derived polymorphism markers

- CDDP is a novel method for generating plant DNA markers and this is the first study about the genetic diversity analysis of C. morifolium by CDDP markers.
- CDDP marker was a more efficient technique to distinguish various chrysanthemum accessions.
- Clustering closely corresponded to inflorescence size and not to petal type or colour type.

The genetic diversity and relationships among 50 cultivars of chrysanthemum (Chrysanthemum morifolium) and 3 wild species, C. nankingense, C. indicum and C. vestitum, were analysed using conserved DNA-derived polymorphism (CDDP) markers. Using 19 selected CDDP primers, 241 bands were generated with an average of 12.68 bands per primer among the 53 accessions, with 223 (92.53%) being polymorphic. The genetic distance between different pairs of genotypes varied from 0.06 to 0.73, averaging 0.36. The 53 accessions were clustered by UPGMA into 6 major groups based on the CDDP marker data. Clustering closely corresponded to inflorescence size and not to petal type or colour type. The minimum number of primers required to distinguish all 53 accessions was 2 (WRKY-R2 and WRKY-R3). There was a significant positive correlation between the resolving power (Rp) of each primer and the number of cultivars identified (r = 0.94, **P < 0.01). The results demonstrated that the CDDP marker system was useful for the identification and genetic diversity analysis of chrysanthemum genotypes. The results provide useful information for the efficient utilisation of chrysanthemum germplasm resources in plant breeding.