Analysis of ITS DNA Sequences of the Korean Native Chrysanthemum

This study investigates the molecular phylogenetic relationships among 15 species in the genus Chrysanthemum and one species of their close related genera Ajania pacifica, an outgroup on the internal transcribed spacer (ITS) region of nuclear ribosomal DNA (nrDNA). The study selected the sequence analysis of ITS regions and evaluated the differences in genetic variation. A total 640-641bp was sequenced at the 5.8S ribosomal DNA and internal transcribed spacer 1 and 2. The 5.8S coding region is 164bp, and has no sequence variations. The length of the ITS sequences aligned using the clustal V program was 640-641bp, and the lengths of the ITS 1 and ITS regions were 254-255bp and 222bp, respectively. The evolutionary rate was very slow in Chrysanthemum ITS region targeting 18S rRNA sequence analysis of the nucleotide length of 14bp, 26S rRNA with coding region 9bp. The speed was high in the DNA sequence evolution particularly in ITS region which was due to the use of good taxa. However, it did not show large variation in the genus chrysanthemum category. The GC content was lower in spacer region ITS1 (46.9 to 51.0%) in chrysanthemums than ITS2 (51.8 to 53.2%) in Asteraceae plant family. The results of the study suggest that the molecular techniques used could be useful for the phylogenetic analysis of Korean chrysanthemum with variations in morphological characteristics.

Additional key words: ITS, sequence, chrysanthemum