Comparative study of tree peony (Paeonia suffruticosa Andr.) cultivars and hybrids by random amplified polymorphic DNA (RAPD) analysis

Random amplified polymorphic DNA (RAPD) assay was performed to categorize or discriminate 14 tree peony (Paeonia suffruticosa) cultivars, a yellow tree peony (P. lutea), a Chinese peony (P. lactiflora) cultivar, and five interspecific cultivars. Forty decamer primers were screened; 11 of these primers produced 108 reproducible amplified DNA bands useful as polymorphic markers. Twenty one genotypes were discriminated with these markers. The similarity values among the genotypes were also calculated with these markers. The results showed that P. suffruticosa cultivars are clearly distinct species from P. lactiflora and P. lutea. Similarity values of yellow flowering hybrid cultivars, 'Kinkaku', 'Kinshi', 'Kinkoh', 'High Noon', and 'Oriental Gold' were between those of P. suffruticosa cultivars and P. lutea. Among P. suffruticosa cultivars, 'Shishigashira', which was introduced to Shimane Pref. from Shizuoka Pref. in the Edo-period, had lower similarity values with cultivars which originated from the Osaka Pref. during the Meiji era. P. suffruticosa cultivars with closely related parentage showed high similarity values (SVs) with both or either parent (s). Cultivar relationships based on SVs established by RAPD markers agreed partly with those based on morphological data, but not on the basis of petal anthocyanidins.