Medicinal plants of Dagala region in Bhutan: their diversity, distribution, uses and economic potential.

BACKGROUND: The traditional g.so-ba-rig-pa hospitals in Bhutan uses more than 100 polyingredient medicines that are manufactured by the Menjong Sorig Pharmaceuticals (MSP). The MSP has been collecting medicinal plants from Lingzhi region for about 48 years and therefore the ecological pressure on these plants have increased. It is MSP's top priority to identify an alternative collection site to ease the problem. Therefore, this study was carried out to determine whether Dagala region could potentially be an alternative collection site for MSP.

METHODS: First the multidisciplinary research team generated a tentative plant list by reviewing a body of ancient g.so-ba-rig-pa literature, current formulations, and the MSP medicinal plants inventory documents. Second, the research team visited the study areas in Dagala region for spot identification of medicinal plants. Third, we confirmed our traditional and botanical identification by crosschecking the descriptions with the series of books on traditional texts, Flora of Bhutan, scientific papers on medicinal plants, and the plant databases.

RESULTS: We have identified 100 species of high altitude medicinal plants from Dagala region. Of these, 24 species grow abundantly, 29 species grow in moderate numbers and 47 species were scarce. More than 85 species belonged to the herbaceous life form and 51 of them are used as a whole plant. A total of 68 species grow in between 4000 and 4999 meter above sea level. These 100 medicinal plants represented 39 different families and 80 genera and the maximum number of plants belonged to the family Asteraceae. Of 60 species that are currently used for formulating medicines at MSP, 16 species have economic importance with potential for commercial collection. Out of seven areas covered by the survey, Kipchen hosted maximum number of medicinal plants (21 species).

CONCLUSIONS: Our survey identified 100 medicinal plants from Dagala region and of these, 16 species has economic potential that could benefit both MSP and Dagala communities. It is feasible to establish an alternative medicinal plants collection center in Dagala Gewog.