Analysis of rDNA ITS sequences of Radix et Rhizoma Salviae Miltiorrhizae and plants of Salvia L / 中草药

ABSTRACT

Objective To study the genetic diversity of ITS sequences of Radix et Rhizoma Salviae Miltiorrhizae (RRSM) and plants of Salvia L. and analyze the utility of ITS sequences in molecular authentication of RRSM and phylogenetic of plants of Salvia L. Methods The ITS gene fragment was amplified using a pair of primers. The PCR products were purified and sequenced by the methods of Sanger dideoxy. Results The DNA sequence of 222-224 bp ITS1, 220-223 bp ITS2 gene fragments and 5.8S rDNA were obtained from 13 samples of Salvia L. The interspecific substitution varied from 0% to 12.16% at ITS1 and 0.5% to 13.51% at ITS2. The intraspecific substitution of RRSM is 0% to 0.9% at ITS1 and 0% to 0.5% at ITS2. The substitution between group of Salvia L. and outgroup varied from 16.07% to 20.27% at ITS1 and 15.91% to 20.27% at ITS2. The phylogenetic tree based on ITS1 and ITS2 data was set up. Conclusion The ITS1 and ITS2 gene fragments are highly conservative at intraspecific level in RRSM, while they are less conservative at interspecific level in Salvia L. They are least conservative between group of Salvia L. and outgroup. Hence, the sequence of this fragment is a good molecular marker for authentication of RRSM and can be used for further study on the phylogenesis for plants of Salvia L.