Genetic Relationships Between Globba expansa (Zingiberaceae) and Other Closely Related Taxa in Thailand Using HAT-RAPD Marker Analysis

Abstract

Globba expansa Wall. ex Horan. is the most well-known and widespread species of the subsection Nudae K.Larsen in mainland Southeast Asia. Several sympatric species with morphological similarities have also been described through its distribution range, therefore creating difficulties in identification among their closely related taxa. To clarify their interspecific relationship, HAT-RAPD marker analysis was carried out for three confusing taxa in this subsection: G. expansa, G. flagellaris K.Larsen, and G. macrochila Sangvir. & M.F.Newman. Seventeen decamer primers were used to generate RAPD products and then to reconstruct a UPGMA dendrogram. Their species recognitions were confirmed since all four accessions of G. expansa were grouped together and placed sisterly to G. flagellaris in the UPGMA tree. A UBC61 primer gave a unique 200-basepair band for G. expansa suggesting that HAT-RAPD could be an effective assay for Globba species identifications. Useful morphological characters to discriminate each species, particularly labellum and staminodes, to discriminate each species were also discussed in this paper