Molecular identification of herbal species belonging to genus Piper within family Piperaceae from northern Peninsular Malaysia

Abstract

Species identification technology (i.e. DNA barcoding) has been recognized as an important and reliable tools, although the effectiveness of using a single universal barcode marker for plants is still questionable. The present study reports a molecular identification method to discriminate 11 plant species within genus Piper that extensively utilized in traditional healing practices in Malaysia. The plants were sampled from six locations that represents three states in northern Peninsular of Malaysia, namely Perlis, Kedah and Penang. Species discrimination was conducted using BLASTn analysis and phylogenetic inference based on Maximum Likelihood and Neighbour-Joining method for two target genes, rbcL and rpoC1. The reliability of phylogenetic tree regenerations was assessed using Disparity Index analysis. Estimation of evolutionary divergence between all samples was employed based on Maximum Composite Likelihood with Kimura 2-parameter model. The present study revealed that the DNA identification method has successfully discriminated all samples to species level and that the rbcL is the reliable marker for identification. The outcome of the present study gives a significant information on the DNA barcoding of plants within genus Piper.