FAN, CHUANZHU*, JENNY QIU-YUN XIANG, AND RICHARDSON ADJOA. Department of Biological Sciences, Idaho State University, Pocatello, Idaho 83209-8007. - Phylogenetic Relationships of Cornus L. Inferred from Nuclear DNA Sequences.
Chuan-Zhu Fan*, (Jenny) Qiu-Yun Xiang, Adjoa Richardson Phylogenetic
Relationships of Cornus L. Inferred from Nuclear DNA Sequences
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