Analisis Biomolekuler Gen Internal Transcribed Spacer (ITS) dalam Studi Filogenetik Zingiber loerzingii Valeton (Zingiberaceae)

Abstract

Zingiberaceae consists of 50 genera and 1400 species distributed in tropical and subtropical areas. The center of the diversity of Zingiberaceae is South Asia and Southeast Asia. Zingiber loerzingii is only found in Sumatera. Unlike other species, this species has not been well studied so the information is still limited, whereas the clarity of plant identity is very crucial. The present study was aimed to determine phylogenetic relationship of Zingiber loerzingii and its relative based on the Internal Transcribed Spacer (ITS) gene. DNA sample was isolated using cetyltrimethylammonium bromide based method of Doyle & Doyle modification. Amplification of ITS region resulted in ± 700 bp amplicon. Sequencing of ITS region of Zingiber loerzingii produced 813 bp DNA sequences that has high rate of evolution. Recontruction of phylogenetic tree was analysed using the Phylogenetic Analysis Using Parsimony program. The results of phylogenetic analysis showed that the genus of Zingiber formed a clade with bootstrap value of 61.9%. The clade consisted of two clades, clade I with bootstrap 62% and clade II with bootstrap 70.8%. Therefore, we conclude that the genus Zingiber is possibly monophyletic. Zingiber loerzingii is nested in clade I with the nearest or sister taxa: Zingiber rubens, Zingiber orbiculatum dan Zingiber fragile.