Identification of Peucedani Radix, Peucedani Decursivi Radix and its adulterants using ITS2 sequence

Abstract

In order to identify Peucedani Radix, Peucedani Decursivi Radix and their adulterants, the internal transcribed spacer 2 (ITS2) regions of Peucedani Radix, Peucedani Decursivi Radix and their adulterants were amplified and bidirectionally sequenced based on the Principles for Molecular Identification of Traditional Chinese Materia Medica Using DNA Barcoding, which has been promulgated by Chinese Pharmacopoeia Commission. Sequences were analyzed and assembled by Codon Code Aligner V3. 7.1. The relevant data were analyzed by MEGA 5. 0. Species identification analyses were performed by using the nearest distance methods and neighbor-joining (NJ) methods. The result showed that the ITS2 sequence lengths of Peucedani Radix were 229-230 bp and the average intra-specific genetic distances were 0.005. The ITS2 sequence lengths of Peucedani Decursivi Radix were 227 bp and the sequences contained no variation site. The average inter-specific K2P genetic distance of Peucedani Radix, Peucedani Decursivi Radix and their adulterants species were 0.044 and 0.065 respectively. The minimum inter-specific divergence is larger than the maximum intra-specific divergence of Peucedani Decursivi Radix. The nearest distance methods and NJ trees results indicated that Peucedani Radix, Peucedani Decursivi Radix and their adulterants species could be identification clearly. The ITS2 regions can stably and accurately distinguish Peucedani Radix, Peucedani Decursivi Radix and their adulterants.