ITS2 Sequences as Barcodes for Identifying and Analyzing Pseudolaricis Cortex / 世界科学技术-中医药现代化

ABSTRACT

Pseudolaricis Cortex and its adulterants were identified using DNA barcoding technique in this study. The sequences of ITS2 of Pseudolaricis Cortex and its five adulterants including 37 samples were analyzed. Se-quences were assembled using CodonCode Aligner 3.5.7. K2P distances were calculated and NJ tree was per-formed applying MEGA5.0. The ITS2 secondary structure was predicted using the ITS2 database and website. The results showed that the haplotypes of ITS2 regions of Pseudolaricis Cortex were the same as that of the original plant leaves. The inter-specific K2P distances of ITS2 were obviously higher than the intra-specific ones. Sam-ples of Pseudolaricis Cortex were clustered into a single clade in the NJ tree. The secondary structure of ITS2 of Pseudolaricis Cortex was significantly different from its adulterants. Therefore, ITS2 could powerfully discriminate Pseudolaricis Cortex and its adulterants.