Specific PCR molecular identification of Dendrobium chrysotoxum / 中草药

ABSTRACT

Objective: To design a pair of PCR primers that could identify Dendrobium chrysotoxum specifically, to optimize the system of PCR detection, and to establish a method to identify D. chrysotoxum rapidly and accurately. Methods: From GenBank database, rDNA 170 ITS sequences in the plants of Dendrobium Sw. were downloaded and compared with all sequences using MEGA 5.0; The variation sites were located, and a pair of specific primers in the non-conservative district were designed. PCR amplification was performed using the specific primers with 35 DNA templates in the plants of Dendrobium Sw., D. chrysotoxum was positive. Results: D. chrysotoxum could be specifically amplificated by specific primers when the annealing temperature was raised to 58 °C, while other plants of Dendrobium Sw. were shown as negative, and the sensitivity of the primer could reach 0.69 ng/μL. Conclusion: This study designs a method that could identify D. chrysotoxum specifically. Using this specific primer could identify D. chrysotoxum rapidly and accurately from the homologous species. This method is well-performed in specificity, and it is more simple, convenient, efficient, and accurate than other methods, such as morphological and microscopical identification, chromatograph, and spectral method.