Sources of Medicinal Orchids and Conservation

Abstract

Unprecedented population growth, industrialisation, mining and motorised vehicle transport have led to rapid depletion of natural resources, shrinkage of forests and reduction in wild species numbers or even their disappearance. In the case of medicinal orchids, the factors which decide whether a species is under threat are threefold: (1) the volume of the demand, (2) whether a species is under cultivation or being harvested from the wild, and (3) whether it has a restricted distribution and its natural habitat is under threat because of human activity. If a medicinal crop can be cultivated and herbalists support the use of the cultivated product, the wild species can continue to thrive in its natural habitat. At one time, more than 100 t of Gastrodia elata (Tianma) tubers were harvested from the wild. Following the discovery of its double mycorrhizal relationship during the 1970s, cultivated G. elata is the mainstay of supply. Extensive farming of Dendrobium catenatum and D. moniliforme has been initiated, and this should eventually reduce the need to employ other species of Dendrobium for Shihu. Bletilla striata is also cultivated.