Development of SCAR Markers to Identify Medicinal Cultivars of Paeonia lactiflora

Paeoniae Radix, the dried root of Paeonia lactiflora, is one of the most important ingredients in Kampo medicine. It is known that Paeoniae Radix is derived from various P. lactiflora cultivars, including medici-nal and horticultural cultivars, and that cultivar identification by DNA analysis has been unsuccessful. We attempted to develop sequence characterized amplified region (SCAR) markers as useful DNA markers for the identification and herbal medicine authentication of two cultivars developed in Japan, 'Bonten' and 'Kitasaisho,' which are two superior medicinal strains of P. lactiflora. Sequence-related amplified poly-morphism (SRAP) analysis was conducted on fourteen P. lactiflora cultivars, and polymorphic fragments specific to 'Bonten' or 'Kitasaisho' were detected. Then, SCAR markers for 'Bonten' and 'Kitasaisho' were developed from the sequence information of these polymorphic fragments. Thirty cultivars of P. lactiflora and five herbal medicine samples were used to validate the specificity of the developed SCAR markers. As a result, we confirmed that our SCAR markers can identify 'Bonten' or 'Kitasaisho' from the plant samples and the herbal medicine samples. Thus, we have successfully designed two highly specific DNA markers and established an easy, rapid, and cost-efficient method to identify specific cultivars of P. lactiflora. Our SCAR markers are expected to contribute to the maintenance of P. lactiflora cultivars such as 'Bonten' as superior medicinal strains, the development of more elite cultivars in the future, and the deterrence of outflow of original cultivars to foreign countries.