| Abstract: | A molecular phylogeny of the subfamily Cyrtandroideae represented by five generaof four tribes was constructed using sequence analysis of the internal transcribed spacers(ITS) and partial 5.8 S rRNA gene (3’end) of nuclear ribosomal DNA. Direct PCRsequencing method was used in the study. The sequences of ITS-1 in the five species rangefrom 234 bp to 258 bp in size and those of ITS-2 from 218 bp to 246 bp. The ITS-1 (258bp) and ITS-2 (218 bp) of Whytockia bijieensis differ greatly from those of the other speciesin size, sequence and G + C content, and therefore the tribe Klugieae represented by W.bijieensis may have diverged from the ancestor of the subfamily Cyrtandroideae at a veryearly time. In PAUP analysis, W. bijieensis was used as the functional outgroup, and onlyone most parsimonious Fitch tree was obtained through exhaustive search. The tree has 353steps, with CI = 0. 932 and RI = 0. 529. In the tree, Chirita crassifolia is basal to amonophyletic group comprising Cyrtandra umbellifera, Briggisia longipes and Annamollifolia, and the monophyletic group is strongly supported by the bootstrap value (97).The tribes Trichosporeae and Cyrtandreae represented respectively by Anna mollifolia and Cyrtandra urnbellifera both evolved from the tribe Didymorcarpeae, which can explain whymany intermediate taxa exist among the three tribes. According to this, the present authorssuggest that the tribe Trichosporeae and the tribe Cyrtandreae be merged with the tribeDidymocarpeae. |
