Genetic Diversity, Population Genetic Structure and Protection Strategies for Houpoëa officinalis (Magnoliaceae), an Endangered Chinese Medical Plant

Houpoëa officinalis is a traditional Chinese medical plant, which has significantly declined in the past decades because of human influence and habitat fragmentation. Twelve expressed sequence tag SSR (EST-SSR) markers developed from the EST sequence of H. officinalis were used to analyse the genetic diversity and structure of fourteen natural populations. The results indicated that moderate genetic diversity and high genetic differentiation existed in this plant (Ho = 0.600, Fst = 0.327). STRUCTURE and UPGMA analyses showed that H. officinalis populations could be divided into 3 different groups, and the west group had higher genetic diversity than the central and east groups. The historical migration rates among the groups were low and unsymmetrical, and there was no significant correlation between Nei’s genetic distance and geographic distance. According to the genetic consequences, conservation strategies (in situ or ex situ, artificial pollination) should be carried out in all populations to preserve genetic diversity.