Genetic relationships of Osmanthus based on ISSR-PCR

Osmanthus is an important gardening plant, but determination of germplasm resources, number of species and bipship among species of Osmanthus are still not clear. In this article, genetic diversity of Osmanthus was first studied by ISSR molecular marker. Based on 20 primers screened from 74 primers, 361 bands were obtained from 17 species, and 95.29 % bands were polymorphic. Furthermore, it was found that the genetic distance between O. attenuatus and O. heterophyllus was the highest (0.5559), and was the lowest (0.2351) between O. ×fortunei and O. heterophyllus. As shown in the dendrogram obtained by UPGMA method, 17 species of Osmanthus could be divided into group I and group II, the group I was composed of O. matsumuraanus, O. americanus, O. yunnanensis and O. attenuatus, and the other species belonged to the group II that was further divided into two subgroups apparently, which were not consistent with the classic classification system, but mostly similar with traditional viewpoint about bipship among species. Therefore, it was feasible and effective to study genetic diversity among species of Osmanthus by ISSR molecular marker.