The tropical regions of the world supply the bulk of current global demand for ''natural medicine'', albeit with increasing uncertainty. India, with its diverse ecological conditions, rich ethnic diversity and a strong traditional knowledge base, accounts for over 45,000 plant species representing 11% of world''s known botanical diversity and 6% of flowering plant diversity. More than 8,000 species are employed in the preparation of herbal drug formulations. Additional demands are being made by the cosmetic and herbal drug formulations. Additional demands are being made by the cosmetic and nutraceutical industry. Ninety percent of the industry''s requirement is sourced from the forests. There is no reliable assessment of the volume or value of the herb-related trade in India. Collection and processing of medicinal plants are said to contribute to at least 35 million workdays of employment every year. Collection is mostly unscientific and destructive, causing irreversible damage to the precious natural resources. The global plant based drug trade is projected around US$ 62 billion with a 7% annual growth rate but India''s share is just 2.5% and almost one-fourth that of China. When so, there is a growing realization that demand is fast outstripping supply, putting an unreasonable pressure on our wild phytoresources. This has already placed certain species at risk. Saussurea lappa is listed under CITES Appendix I and Aquilaria malaccensis, Dioscorea deltoidea, Nardostachys grandiflora, Picrorhiza kurroa, Podophyllum hexandrum, Rauvolfia serpentina and Taxus wallichiana are placed under Appendix II. Others will soon follow if immediate corrective measures are not taken.

Ongoing conservation efforts in the country are directed towards both in situ and ex situ approaches. In situ measures are, of course, ideal. The Ministry of Environment and Forests has established a protected area network of around 150,000 km2 established under the Wildlife (Protection) Act, 1972. In addition, community initiatives in the form of ''sacred groves'' - dedicated to particular local deities - play a very useful role. Collection of plants or parts thereof is taboo in such preserves. Medicinal plants, however, do not receive any special attention in either of these.

Ex situ conservation measures include maintenance of species in botanical gardens, herbal gardens and ''vanaspati vans''. It is also possible to preserve propagules variety of depositories broadly referred to as ''gene banks''. The latter preserve samples; of seeds, pollen, in vitro-regenerated material and DNA samples on medium to long term basis. Long term preservation is possible under liquid nitrogen in cryo banks. The Department of Biotechnology has established four gene banks specifically devoted to the conservation of medicinal and aromatic species of the country. These are located at the Central Institute of Medicinal and Aromatic Plants, Lucknow; National Bureau of Plant Genetic Resources, New Delhi; Regional Research Laboratory, Jammu; and Tropical Botanical Garden and Research Institute, Thiruvananthapuram. More recently, a fifth gene bank has been added to cater exclusively to Ayurvedic plants, at the Arya Vaidya Sala Kottakal. The paper describes the role of biotechnology in conservation of our medicinal plant resources.

The Department of Biotechnology has established four gene banks specifically devoted to the conservation of medicinal and aromatic species of the country. These are located at the Central Institute of Medicinal and Aromatic Plants, Lucknow; National Bureau of Plant Genetic Resources, New Delhi; Regional Research Laboratory, Jammu; and Tropical Botanical Garden and Research Institute. More recently, a fifth gene bank has been added to cater exclusively to ayurvedic plants, at the Arya Vaidya Sala Kottakal.