[Molecular identification of medicinal plants: Dendrobium chrysanthum, Dendrobium fimbriatum and their morphologically allied species by PCR-RFLP analyses].

Aim: To establish a simple method for molecular identification of original plants of D. chrysanthum and D. fimbriatum using molecular marker rDNA ITS region.

Methods: Restriction patterns of ITS fragments were obtained using PCR-RFLP method. The PCR products of D. chrysanthum and its morphologically allied species were digested at 37 degrees C by Cla I and Apa LI, those of D. fimbriatum and its morphologically allied species were digested by Sph I.

Results: D. chrysanthum, D. fimbriatum and their morphologically allied species could be identified by predicted restriction profiles of PCR-RFLP. The botanical origin of twenty-five fresh samples of "Shihu" collected in markets was identified by this method.

Conclusion: The results showed that PCR-RFLP analysis of the rDNA ITS region is a feasible, simple and inexpensive method for determining the botanical origin of the traditional Chinese medicine "Shihu".