Phylogeny of Korean Opuntia spp. based on multiple DNA regions

Although Opuntia species are of high agronomic value in Korea, the taxonomic position of Korean Opuntia species has never been investigated. The taxonomic position of Korean Opuntia spp. Within the tribe Opuntieae was examined based on DNA sequence analysis of matK, trnL-F, atpB-rbcl, and ITS regions. The total amplified sequence length was 2977 bp; only 18 parsimonious informative sites were present, even though they belonged to different species. A phylogenetic tree using both the maximum likelihood method with 2000 bootstrap replications and Bayesian posterior probabilities was constructed. The new forma, Opuntia humifusa f. Jeollaensis, used in this study was placed within the Macrocentra clade rather than the Humifusa clade. The genetic distance between O. Humifusa f. Jeollaenis and O. Camanchica was the lowest among all Opuntia spp. Analyzed in this study. Korean O. Ficus-indica was genetically closer to O. Engelmannii than to O. Ficus-indica previously reported. Opuntia engelmannii and O. Ficus-indica have been considered conspecific previously, and so it is likely that the Korean O. Ficus-indica used in this study may be a relative of O. Engelmannii or may have arisen from a lineage different to the O. Ficus-indica used in the analysis.