Molecular phylogenetic analysis of Asclepiadoideae (Apocynaceae s. l.) in Taiwan

• Main Authors: Hsin-Bang Tsai, 蔡信邦
• Other Authors: Hsin-Mei Ku
• Format: Others
• Language: en_US
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/70023621190595187744

碩士 === 國立中興大學 === 農藝學系所 === 103 === Asclepiadoideae is comprised by 10 genus and 21 species in Taiwan, morphological characters from leaf, flower to colleters which require microscopic techniques, can used to delimit each species well, but the phylogeny within Asclepiadoideae is still unclear. In this study, two nrDNA ITS(Internal Transcribed Spacer)、G3DPH (Glyceraldehyde-3-phosphate dehydrogenase), and cpDNA trnL-F (tRNA-UAA to tRNA-GAA) were used to reconstruct the phylogeny by different analysis. Results showed that three major groups, Asclepiadeae, Ceropegieae and Marsdenieae, were evident using different gene sequence data. At genus level, Marsdenieae is not monophyletic, M. formosana and M. tintoria are morphological distinct species, the classification of Marsdenieae should be reexamined. The species from sect. Vincetoxicum and other Cynanchum species formed two distinct clades, sect. Vincetoxicum and Tylophora are paraphyletic. This is also supported by latex color and corona characters which indicate that Vincetoxicum and Tylophora should be lumped together. T. oshimae and T. taiwanensis are ancestral taxa in Tylophora, relationships among T. brownii, T. sui, T. insulana, T. lui and T. ovata are not accessible using ITS and trnL-F due to poor sequence variation. However, data from G3DPH has successfully grouped T. ovata, T. lui and T. insulana in the basal position. In conclusion, this study successfully reconstructed phylogeny of Asclepiadoideae using molecular data, in which G3DPH would be especially useful to reconstruct the phylogeny of Tylophora in Taiwan.