PCR-RFLP ANALYSIS OF THE CHLOROPLAST GENE trn K IN THE PINACEAE, WITH SPECIAL REFERENCE TO THE SYSTEMATIC POSITION OF CATHAYA
The molecular phylogeny of the Pinaceae represented by 13 species of 10 genera was constructed from PCR-RFLP analysis of the chloroplast gene trn K, which was approximately 2557 bp long. Ninety-two restriction sites, of which 68 were variable, were identified by 16 restriction enzymes. Thirty-five of the 68 polymorphic sites were phylogenetically informative. The restriction site data were analyzed by PAUP (version 3.1.1) with both the Wagner parsimony method and the Dollo parsimony method. As a result, Dollo and Wagner parsimonious trees have similar topologies except for the position of Cedrus. The Abies-Keteleeria-Tsuga-Pseudolarix clade was well resolved in all trees. Pseudotsuga is closely related to Larix, while Abies is relatively closely related to Keteleeria. As an isolated genus, Cathaya is distantly related to the Abies-Keteleeria-Tsuga-Pseudolarix clade, and is not very closely related to any other genus of the Pinaceae.