DNA Barcoding the Plant of the Casuarina / 世界科学技术-中医药现代化

ABSTRACT

In this research, Casuarina eguisetifolia Linn was used to verify the broadly suitability of DNA bar-codes in identification of Li-medicine plants and systematic development of species. The genomic DNA of 22 samples collected C. eguisetifolia and its adulterants were amplified by 4 pairs of primers respectively (ITS (inter-nal transcribed spacer), ITS2 (internal transcribed spacer 2), trnH-psbA , rbcL) and sequenced bi-directionally. Obtained sequences were assembled using CodonCode Aligner. The dates were analysised using MEGA5.1 in ac-cordance with the kimura 2-parameter (K2P) model. The neighbor-joining (NJ) phylogenetic trees were construct-ed. Our study demonstrated the efficacy of ITS/ITS2 to distinguish between C. eguisetifolia and other adulterants species at the molecular level. Comparative to the primer of trnH-psbA and rbcL, there was a obviously DNA gap. The NJ trees showed that the several species of Casuarina can be classified to same types to show a obvi-ously monophyly, which the nearest family was Guttiferae. Therefore, ITS/ITS2 regions can accurately distinguish the original plant of Li-medicine. The systematic evolution of Casuarina can be verified in the molecular level.