Progression of the desertification in northern China has been causing damage to wild
Ephedra plants on which we depend for most of supply of the traditional herbal medicine, “Ma huang.” The Chinese government encourages the cultivation of
Ephedra plants, and
Ephedra fields have been reclaimed in the original
Ephedra habitats in recent years. We surveyed 7
Ephedra fields that have been recently developed in the Inner Mongolia Autonomous Region and Ningxia Hui Autonomous Region to collect information on
Ephedra plant cultivation, especially pertaining to crop species. Specimens taken from those
Ephedra fields were genetically and morphologically analyzed, and their ephedrine alkaloid content was examined. DNA analyses of
Ephedra specimens, including DNA sequencing of ITS (internal transcribing sequence of nuclear ribosomal DNA) and
trn L/F (intron of
trnL and intergenic spacer between the
trnL and
trnF of chloroplast DNA) region and species-specific amplification of
trn L/F were conducted to identify
Ephedra species. Based on the results of DNA sequencing and morphological determination, the crops grown in 6 fields ware identified as
Ephedra sinica, while co-planting of
E. sinica and
E. intermedia was found in one field where a higher appearance rate of plants with varied morphology from wild
Ephedra plants was observed. Furthermore, direct sequencing of the PCR product of the
trn L/F region of some specimens from the field and their species-specific PCR showed ambivalent result. Cloning and sequencing of the PCR product of the
trn L/F region of those specimens DNA suggested their heteroplasmy, containing both
E. sinica- and
E. intermedia-type chloroplasts. On the other hand, the profile of the ephedrine alkaloid content was clearly correlated with the result of direct sequencing of the
trn L/F region; the specimens showing the
E. sinica-type sequence contained more ephedrine than pseudoephedrine, and the specimens of the
E. intermedia-type more pseudoephedrine.
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