Phylogenetic Relationships in Actinidia as Revealed by RAPD Analysis

AIK+TXACT. Phylogenetic relationships within theftcfinidio were investigated usingrandomly amplified polymorphic DNA (RAPD) markers. DNAs from 10 taxa, including31 species encompassing all four sections and four series of the traditional subdivisions within the genus, were amplified using 22 preselected IO-mer oligonucieotide primers. A total 204 DNA bands were scored across the 10 taxa, of which 188 (92%) were polymorphic. A wide range of genetic similarity was observed among the taxa (0.13 to 0.61). The average similarity between varieties of the same species was 0.54, and between different species was 0.28. respectively. Although the phylogenetic analysis revealed a clear indication that section Leiocarpue was a monophyletic group, subdivisions of the other three traditional sections were poorly supported. The UPGMA phenogram showed that the majority of the species clustered into geographic subgroups in accordance with their natural dis tr ibut ion ( the Yangtzi River , southeastern China, southern China and southwestern China) . The intrageneric subdivisions ofActiizi&zappeared to be difficult, but some subdivisions could be explained by the geographic distribution of the species, particularly for species of Gang’s sections of Maculatae and Stellutue. The phylogenetic relationships among several species with previous taxonomic uncertainty are also discussed on the basis of the RAPD data. The results of this s tudy supplement our previous understanding of the Actinidiu t a x o n o m y b a s e d s o l e l y o n morphological characters.