The Study On Epigenetic Structure Of Panax Ginseng

Chinese ginseng(Panax ginseng C.A.Meyer) is a precious medicinal herb, which belongs to the Araliaceae. Three hundred years ago, people began to domesticate the ginseng. At present, there are two major ecotypes forms in China, wild ginseng and cultivated ginseng. Compelling evidence has established that cultivated ginseng was domesticated from wild ginseng. In order to understand that the impact of domestication for ginseng epigenetic structure, the research work was carried out. In this study, Methylation-sensitive Amplified Polymorphism(MSAP) analysis was performed on 47 Chinese ginseng samples, including 32 cultivated ginseng samples and 15 wild ginseng samples. The eleven selected primers of MSAP generatred a total of 720 methylation sites across the 47 individuals, the MSAP data were dissected into methylationinsensitive and methylation-sensitive polymorphism,MISP and MSP. According to MISP analysis, the genetic diversity parameters of cultivated ginseng(h=0.0862, I=0.1401, PPB=39.31%) is lower than that of wild ginseng( h=0.1728,I=0.2681,PPB=58.06%), the genetic distance between them is 0.0343. In the light of MSP analysis, the epigenetic diversity parameters of cultivated ginseng(h=0.0825,I=0.1325,PPB=38.61%) is also lower than that of wild ginseng(h=0.1400,I=0.2206,PPB=49.86%), the epigenetic distance between them is 0.0164. At the same time, we noted that cultivated ginseng showed significant lower level of CHG methylation than that of wild(t-test, p <0.01), the level of CG showed relatively lower than wild(t-test, p < 0.05). In other words, cultivated ginseng possessed relatively low level of cytosine methylation compared to wild ginseng. Based on the analysis of the above, the study indicated that domestication has indeed shaped the genetic and epigenetic structures of cultivated ginseng, Which will provide theoretical basis for domestication and genetic breeding.