Paeonia ostii,which belongs to Paeoniaceae,is one of the famous ornamental and medicinal plants in China.It is also the main species to Jiangnan Mudan Group.Postii is a good material for breeding and researching because of its strong resistance and fruitfulness.However,there were few reports to its distribution,and the studies on the genetic diversity of P.ostii also need to be systematic.According to its area distribution,tree peony can be divided into four main variety groups,they are Zhongyuan (Ce...