2000/12/04 by Chatchai Ngamriabsakul, Mark F. Newman, Quentin Cronk · 53 citations
Agricultural and Biological Sciences · Medicine · Pharmacology, Toxicology and Pharmaceutics · #Biology #Botany #Clade #Disjunct #Ethnobotanical and Medicinal Plants Studies #Evolutionary biology #Genetics #Genus #Ginger and Zingiberaceae research #Internal transcribed spacer #Monophyly #Pharmacological Effects of Medicinal Plants #Phylogenetic tree #Population #Ribosomal DNA #Sister group #Taxon #Zoology
paper · doi:10.1017/s0960428600000032
published in Edinburgh Journal of Botany 57(1), 39-61 (Royal Botanic Garden Edinburgh)
openalex publication_date 2000/12/04 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/08
A phylogenetic study of Roscoea (Zingiberaceae), a high-altitude genus of an otherwise tropical plant family, was undertaken using sequence data from the internal transcribed spacers (ITS) of the nuclear ribosomal DNA (nrDNA). Two species of Cautleya and two species of Curcuma were used as outgroups. This resulted in an aligned matrix of 436bp (ITS1, 203bp; ITS2, 233bp). Sequence divergence of ITS1 and ITS2 within the ingroup ranged from 0–13.9% and 0–7.6% respectively. The results suggest that Roscoea is monophyletic (BS=99%; DI=>3) with the genus Cautleya as sister group. Roscoea itself is divided into two sister clades which correlate with geography: a ‘Chinese’ clade (BS=67%; DI=+2) and a ‘Himalayan’ clade (BS=59%; DI=+1). These two groups are disjunct across the ‘Brahmaputra gap’, a region in which no Roscoea spp. have been recorded. The only species which occurs on both sides of the Brahmaputra gap is Roscoea tibetica. However, the western populations of Roscoea tibetica (from Bhutan) show numerous morphological differences. It is therefore possible that Bhutanese R. tibetica represents a distinct taxon, possibly more closely allied to Himalayan species.