Genetic differences among populations of Gynura procumbens (Lour.) Merr.

Twenty-four populations of Gynura procumbens from different geographical regions were studied to determine the genetic differences using ITS and trnL-trnF sequences. The ITS sequence had an aligned length of 718 bp and a G+C content of 49.8%, with 5 variable sites and 3 parsimonious informative sites. The trnL-trnF sequence had an aligned length of 835 bp and a G+C content of 35.0%, with 6 variable sites and 3 parsimonious informative sites. The phylogenetic tree based on trnL-trnF sequences showed that all populations of Gynura procumbens clustered into one branch, indicating that this sequence has strong identifying abilities in genetic difference studies. Furthermore, the phylogenetic analysis using both ITS and trnL-trnF sequences showed similar results. Populations collected from Taiwan and Indonesia were grouped into one clade, while those collected from Guizhou, Guangxi, Fujian, and Guangdong shared a close relationship, corresponding to their geographical distribution pattern.