Molecular authentication of Dendrobium loddigesii Rolfe by Amplification Refractory Mutation System (ARMS).

As a widely used medicinal plant, Dendrobium loddigesii Rolfe is always a possible target for fraudulent labeling. The identification of D. loddigesii is generally difficult from its morphological and chemical appearance only. In order to develop a convenient and efficient identification method for D. loddigesii, six pairs of diagnostic ARMS primers were designed based on nrDNA ITS sequences of D. loddigesii and eleven adulterants. The results showed that one diagnostic primer pair (FJB-04-forward, FJB-04-reverse) could be used to authenticate D. loddigesii by generating a fragment of 353 bp at annealing temperatures from 48 degrees C to 62 degrees C while the other diagnostic primer pair (FJB-03-forward, FJB-03-reverse) took on the same effect at annealing temperatures from 49 degrees C to 55 degrees C. This points out the potential of ARMS analysis for authentication of D. loddigesii.