J Syst Evol ›› 1998, Vol. 36 ›› Issue (5): 403-410.

• Research Articles • Previous Articles     Next Articles

The Systematic Position of Beesia: Evidence from ITS (nrDNA) Sequence Analysis

WANG Xiao-Quan, DENG Zheng-Rong, HONG De-Yuan   

  • Published:1998-09-10

Abstract: Discussed in the present paper is the systematic position of Beesia, a small ranunculaceous genus mainly distributed in SW China. Sequences of the internal transcribed spacers (ITS) and 3’ end of 5.8 S rRNA gene of Beesia calthifolia, Trollius chinensis, Cimicifuga acerina, C. brachycarpa and Actaea asiatica were determined by direct PCR sequencing method. The sequences of ITS-1 in the five species range from 225 bp to 232 bp in size and those of ITS-2 from 201 bp to 217 bp. Beesia is very similar to Cimicifuga and Actaea not only in size, sequence and G+C content of ITS, but also in sequence of 3’ end of 5.8 S rRNA gene. In PAUP analysis, Ranunculus enysii was used as outgroup, and the most parsimonious tree was obtained through exhaustive search. The gaps were treated respectively as missing characters and the fifth base in two analyses. The two analyses show that a monophyletic group comprising Beesia calthifolia, Cimicifuga acerina, C. brachycarpa and Actaea asiatica is strongly supported by the bootstrap value. In the monophyletic group, Beesia calthifolia is basal to the other three species. The present DNA sequence analysis demonstrates that the genus Beesia should be placed in the tribe Cimicifugeae, which is consistent with the results from phytochemistry, palynology and cytology. In addition, Beesia may be the most original genus in the tribe Cimicifugeae in view of simple leaf,apetalous flower and molecular evidence.

Key words: Beesia, Trollieae, Cimicifugeae, ITS, Molecular phylogeny