Identification of origin plant of Uygur medicine mulberry based on DNA barcode

Abstract

To provide molecular evidence for medical material identification, we analyzed the nucleotide sequence of ITS2, psbA-trnH gene in Morus genus plants and commercial products which were obtained from different places in Xinjiang. The sequence of ITS2 and psbA-trnH in fifty-one samples were amplified and sequenced, MEGA 6.0 was used to analyze the intra- and interspecific K-2P distances, neighbor-joining (NJ) tree was used to constructing clustering tree. ITS2 sequence analyzed results showed that there is no intra-specific variation among Morus alba, M. alba var. tatarica and M. nigra, but 13 variations sites were exist between M. alba and M. nigra and their inter-specific K-2P distances was 0.04, which indicated that there had significant variation in them. We didn't find informative variation sites between Morus genus plants and commercial products, and we also found that M. nigra can be distinguished from other two species by NJ Tree. PsbA-trnH analysis results showed there was only one variation site between M. alba and M. nigra, but insertion or deletion variation were remarkable evidence among M. alba, M. alba var. tatarica and M. Nigra. Inter-specific variation was accordance with intra-specific variation of commercial products. So ITS2 and psbA-trnH gene were important marker for M. alba, M. alba var. tatarica and M. nigra identification. This study provided important evidence for Uygur medicine identification and market supervision.