Previous phylogenetic analyses of Cornus using cpDNA data and morphological characters suggested different relationships within the genus. Independent data sets containing sequences from nuclear 26S and ITS1-5.8S region of rDNA were generated for Cornus L. to test the phylogenetic hypotheses based on chloroplast DNA and morphological data. The obtained 26S rDNA sequences were easily aligned with few gaps consisting of 3465 bp, but sequences from the ITS1-5.8S region were difficult to align unambiguously among subgroups of the genus. Phylogenetic analyses of these sequence data were conducted using PAUP4.0b4. Results from 26S rDNA sequences suggested relationships among subgroups congruent with those inferred from cpDNA data. That is, the dwarf dogwoods and the big-bracted dogwoods are sisters, which in turn, the sister of the cornelian cherries. The blue- or white-fruited dogwoods form a clade sister to this red-fruited. However, results from the ITS1-5.8S region suggested different relationships within the red-fruited dogwoods (i.e., the dwarf dogwoods are sister to the cornelian cherries).

Key words: Cornus, Nuclear DNA, Phylogentic Relationship, Sequencing