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.
Keywords
DNA marker, Globba expansa Wall. ex Horan., HAT-RAPD, Thailand, Zingberaceae