Preliminary Study On DNA Fingerprinting Of Peony Curtivars

Peaonia suffruticosa and P. lactiflora are Chinese famous traditional plant, playing an important role in Chinese gardening and people's cultural life. The objectives of this study are to develop superior cultivars, and to effectively conserve and utilize the superior genetic resources, to identify new cultivars for registration. DNA fingerprinting were established for typical varieties, based on the AFLP techniques and the DNA fingerprinting, the identification of tree peaonies and herbaceous peonies cultivars were studied with use of SSR software. The main results were as follows:(1) An AFLP system suitable for P. suffruticosa and P. lactiflora was developed, clear and high resolution bands were obtained with appropriate handlings in sample collection, DNA extraction, restriction-ligase reaction, and double amplification as well as staining techniques throughout the experiment process.(2) With use of Mse I - EcoR I digest and primers, fingerprinting of the 11 samples were obtained. P. suffruticosa ,With 5 combinations of primers, we obtained 257 bands among which 214 were polymorphic ones with 80.4% percentage of polymorphism being; Paeonia lactiflora , With 4 combinations of primers, we obtained 215 bands among which 179 were polymorphic ones with an average identifying percentage of 95.87%. The result showed that AFLP was truly a useful tool to test polymorphism among closely-related cultivars. 9 combinations of primers distinguished all tested cultivars completely, 11 cultivars were found to have cultivar-specific(having or missing)AFLP fingerprinting. The result showed that AFLP was one of the most effective method in identifying cultivars at present.(3)The primer E-AGG/ M-CAG was proved to be ideal combinations of primers for AFLP analysis of P. suffruticosa . The primer E-ACT/ M-CAT are better ones for P. lactiflora.(4)In the analysis among similar cultivars, singer pair of primer was not enough to distinguish their difference sometimes. We should select two or more pairs of primers to analysis and combine some other traditional methods.(5)'Guan Shi Mo Yu' is possible a natural hybrid of 'Yan Long Zi Zhu Pan' and 'Hei Hua kui' and is also likely be affected by other cultivars. 'Primevere'and 'Zhong Sheng Fen 'have higher genetic similarity,genetic distance is 0.6667.(6)AFLP is an effective method for plant identification and classification. Combination of AFLP techniques with morphological, palynologicah catonological and enzyme techniques is essential for variety identification.The preliminarily constructed fingerprinting provided useful information not only for developing superior cultivars and new variety right protection but also for conservationn and utilization the genetic resources. The improved systems could be used to construct standardized fingerprinting archive of genetic map, marker-assisted selection and map based cloning in peony . The results, therefore, will produce important effects on genetic improvement of peony at the molecular levels.