India is one of the 12 mega biodiversity centres of the world with two major hot spots of endemic species and 49,000 plant species reported in 16 agro-climatic zones of the country. There are about 15,000 to 20,000 plant species reported to have medicinal value with 30% considered as endemic to the country. Among these 7,000-8,000 are reported to be used in unregulated informal systems of medicine and 1,200-2,000 in the regulated AYUSH (Qazi, 2003). Some of the medicinal and aromatic plants found in India along with their traditional uses are listed in Table 1 (Ahmad et al., 1998).
Around 70% of Indian medicinal and aromatic plants are found in tropical areas mostly in various forest types spread across the Western and Eastern Ghats, the Vindhyas, the Chotta Nagpur plateau, the Aravalis ranges and the Himalayas. Although less than 30% of the medicinal and aromatic plant species are found in the temperate and alpine areas and higher altitudes, they include species of high medicinal value. About 90% of the medicinal plants used by industries are collected from the wild. While over 800 species are used in production by industry, less than 20 species of plants are under commercial cultivation. More than 70% of the plant collections in India involve destructive harvesting because of the use of parts such as roots, bark, wood, stem and the whole plant in the case of herbs. As a result several medicinal plants have been assessed as endangered, vulnerable and threatened due to over or unskilful harvesting and habitat destruction in the form of deforestation in the wild. The government of India has put 29 species, which are believed to be threatened in the wild, on the negative list of exports (Anonymous, 2000).
India’s diverse agro-climatic zones, variation in regional topography and in flora and fauna has contributed to the richness of its biological diversity. Depending on the availability of principal medicinal plants, the country has been divided into eight phytogeographic regions. The major species of medicinal and aromatic plants found in different regions are listed in Table 2 (Datta, 2001).
India, with its rich and ancient culture of using medicinal plants, has discovered herbs for all human ailments. The country is also famous for its spices for which it has a long tradition of use and production. More than 50 kinds of spices are produced, some in huge quantities. Indian consumption of spices is among the highest in the world with more than 90% of the domestic production used locally (Vasisht and Maninder, 2003). The Indian states with their respective areas under cultivation of medicinal plants are presented in Table 3 (Rajasekharan, 2004).
Brazil, Indonesia, China and India are the leading world producers of essential oils. However, as the consumption of essential oils in India is very high, very little is made available for export. The important essential oils produced in India are from sandalwood, lemon grass, palmarosa, eucalyptus (Eucalyptus citriodora Hook. and Eucalyptus globulus Labill.), mentha, khus and linaloe. Some commercially important plants in India that provide essential oils are listed in Table 4 (FAO, 2002).
National Institute of Ayurveda (NIA) Jaipur (http://www.nia.nic.in)
National Institute of Homeopathy, Kolkata; (http://nih.nic.in)
National Institute of Naturopathy, Pune; (http://www.punenin.org)
National Institute of Unani Medicine, Bangalore (http://www.nium.in)