The World Health Organization (WHO) has estimated the present demand for medicinal plants is approximately US $14 billion per year 34. The demand for medicinal plant-based raw materials is growing at the rate of 15 to 25% annually, and according to an estimate of WHO, the demand for medicinal plants is likely to increase more than US $5 trillion in 2050. In India, the medicinal plant-related trade is estimated to be approximately US $1 billion per year 35. According to an estimate, the quantity of export of Ayurvedic products produced in India has tripled between last two financial years (2001–2002 and 2002–2003; Figure 1).

The projected escalating demand of medicinal plants has led to the over-harvesting of many plants from wild, which subsequently results in the loss of their existing populations. For example, the large quantity of Himalayan yew (Taxus baccata) has been gathered from the wild since its extract, taxol, was established as a use in the treatment of ovarian cancer. Aconitum heterophyllum, Nardostachys grandiflora, Dactylorhiza hatagirea, Polygonatum verticillatum, Gloriosa superba, Arnebia benthamii and Megacarpoea polyandra are other examples of north Indian medicinal plant species which have been overexploited for therapeutic uses and have subsequently been placed today in rare and endangered categories. Many medicinal plant species are used in curing more than one disease 3637, and as a result, these species are under pressure due to over collection from wild. For example, Hemidesmus indicus is used to cure 34 types of diseases; Aegle marmelos 31, Phyllanthus emblica 29, and Gloriosa superba 28 (Table 3). Over-exploitation and continuous depletion of medicinal plants have not only affected their supply and loss of genetic diversity, but have seriously affected the livelihoods of indigenous people living in the forest margins 17.

More than 95% of the 400 plant species used in preparing medicine by various industries are harvested from wild populations in India 38. Harvesting medicinal plants for commercial use, coupled with the destructive harvest of underground parts of slow reproducing, slow growing and habitat-specific species, are the crucial factors in meeting the goal of sustainability 3940. Harvesting shoots and leaves of medicinal plants may decline their photosynthetic capacity, and as well as the potential for survival and effective propagation. Medicinal plants tolerance to harvest varies with climatic conditions as the temperate herbs become highly vulnerable to harvest of individuals 41. Furthermore, rising demand with shrinking habitats may lead to the local extinction of many medicinal plant species.

The continuous exploitation of several medicinal plant species from the wild 42 and substantial loss of their habitats during past 15 years 43 have resulted in population decline of many high value medicinal plant species over the years. The primary threats to medicinal plants are those that affect any kind of biodiversity used by humans 1744. The weakening of customary laws, which have regulated the use of natural resources, are among the causes of threatening the medicinal plant species 4045. These customary laws have often proved to be easily diluted by modern socio-economic forces 4. There are many other potential causes of rarity in medicinal plant species, such as habitat specificity, narrow range of distribution, land use disturbances, introduction of non-natives, habitat alteration, climatic changes, heavy livestock grazing, explosion of human population, fragmentation and degradation of population, population bottleneck, and genetic drift 14464748. Additionally, natural enemies (i.e., pathogens, herbivores, and seed predators) could substantially limit the abundance of rare medicinal plant species in any given area 4950.

In addition to the consumption of medicinal plants by animals, there are physical ailments in humans, which are cured by different species of the same genera. For example, the malarial fever is treated by many species of Swertia (e.g. Swertia chiraiyta, S. angustifolia, and S. cordata). Similarly, different species of Berberis (e.g. Berberis aristata, B. asiatica, B. lycium, B. chitria and B. jaeschkeana) are used as a source of berberidine to cure certain eye diseases. Furthermore, different species of the same genera contain different proportions of chemical quantity, and there is a preference over their demand; however, the degree of threat for their exploitation is relatively lower than those species, which do not have alternatives

An estimated 4,000 to 10,000 species of medicinal plants face potential local, national, regional or global extinction, with subsequent serious consequences for livelihoods, economies and health care systems 51. Although, a few studies exist on the rare and endangered medicinal plant species of the northern India 814485253, none of these studies have complete data set for even a single species. In 2003, 71 rare and endangered medicinal plant species have been assessed for the northwest Himalaya during the Conservation Assessment and Management Plan workshop, according to the guidelines of the World Conservation Union. In northern India, Aconitum is the rarest genus with 5 species, followed by Rheum with 4 rare species. Out of the 71 rare medicinal plants, 92% are in active trade; 74% are traded nationally and 35% are traded internationally 52.

The meager availability of data on the population and quantum of rare species in nature, however, has restricted their categorization to a few species on the basis of herbarium collection and by consultation by a few experts 14. The present assessments are also questioned for their validity on the assignment of threat categories to the species, including the number of taxa in danger for specific area. The problems in assessing the species is increased in the mountainous region, especially high altitude areas because of tough and inaccessibility of the terrain, inhospitable climatic conditions, and short life cycle of plants. Most of the available data have been collected from the easily accessible areas in these mountains. Indigenous communities and commercial herb gatherers also raid these same areas for collection of medicinal plants. Therefore, the estimated population density of categorized rare medicinal plants is not precise because it differs the areas that never and hardly undergone any collection of such rare medicinal plant species 54.

Information on the propagation of medicinal plants is available for less than 10% and agro-technology is available only for 1% of the total known plants globally 5556. This trend shows that developing agro-technology should be one of the thrust areas for research. Furthermore, in order to meet the escalating demand of medicinal plants, farming of these plant species is imperative. Apart from meeting the present demand, farming may conserve the wild genetic diversity of medicinal plants. Farming permits the production of uniform material, from which standardized products can be consistently obtained. Cultivation also permits better species identification, improved quality control, and increased prospects for genetic improvements. Selection of planting material for large-scale farming is also an important task. The planting material therefore should be of good quality, rich in active ingredients, pest- and disease-resistant and environmental tolerant. For the large scale farming, one has to find out whether monoculture is the right way to cultivate all medicinal plants or one has to promote polyculture model for better production of medicinal plants.

Studies conducted on the agro-forestry of medicinal plants elsewhere suggest that since many medicinal plant species prefer to grow under forest cover, agroforestry offers a convenient strategy for their cultivation as well as conservation through: 1) integrating shade tolerant medicinal plants as lower strata species in multistrata system, 2) cultivating short cycle medicinal plants as intercrops in existing stands of tree crops, 3) growing medicinal tree as shade providers and boundary markers, and 4) inter-planting medicinal plants with food crops 17. Notwithstanding, it is understood that the cultivation of medicinal plants is not an easy task as the history of medicinal plants farming reflects. Many farmers in trans-Himalayan region of northern India have replaced the medicinal plants farming with common crops [i.e., peas (Pisum sativum), potatos (Solanum tuberosum) and hops (Humulus lupulus)] due to the lengthy cultivation cycle of medicinal plants like Saussurea costus 7. The cost of many medicinal plants in northern India is lower than many seasonal vegetables 58, which is a cause of scanty farming of medicinal plants.

Attempts are being made by different organizations to cultivate various medicinal plant species, including rare and endangered categories. Agro-technology for about 20 species of rare and endangered medicinal plants of the northern India has been developed by different organizations 52. However, the per hectare cost of cultivation, total annual production and cost benefit ratio fluctuate with different medicinal plant species. Out of 10 selected rare and endangered medicinal plant species, Rheum emodi was calculated as a most beneficial cash crop of the medicinal plant in terms of net income generation in northern India (Table 4). At present, however, the farming of most of the medicinal plant species is being operated on a small scale and is restricted to a few hectares of land in various states of northern India. There is an uncertainty of obtaining the necessary permits from government agencies for cultivation of medicinal plants. Additionally, many farmers are unaware about the agency responsible for issuing permits. If the farmers are not granted permits needed to cultivate, they are forced to sell their products on the illegal market, which exposes them to action by government agencies and the exploitation by middlemen 1459.

The former remote green forests have now become part of a dynamic, profit-seeking economy and demanding pluralistic politics worldwide. Reducing the pressure on various forest products, especially on the medicinal plants, is therefore a tough challenge both for policy makers and for economists. Medicinal plants are the local heritage with global importance. The Convention on Biological Diversity at Rio had agreed on a framework that would help the biodiversity to be utilized in a prudent and controlled way. Bio-prospecting, at present, occurs in an environment of suspicions and growing tensions between the bio-piracy and rights of sharing benefits between the developing and developed countries 60. Most of the issues relating to the protection of the legal status for indigenous knowledge and compensation of the indigenous herbal practitioners for that knowledge are extremely complicated. There are arguments for the present state of compensation or benefit sharing under the intellectual property rights, which is being considered a new legal form of bio-piracy by one group, whereas other groups argue that the intellectual property right is a legal tool to protect the rights of knowledge holders 61.

Different ways and systems for awarding patents on the medicinal plants in India, United States, Europe, Canada and other countries have widened the confusion 62. In many countries, the plants and inventions directed to the plants and the plant products (i.e., seeds, flowers, gums, and resins) are not eligible for filing a patent. In United States, however, any living organism derived by human invention, such as by breeding or by laboratory-based manipulation, can be filed for awarding patent. The Indian Protection of Plant Varieties and Farmers Rights Act of 2001 recognizes the contribution of farmers who actively participate in the breeding programs. Furthermore, this act contains provisions for benefit sharing whereby local communities are acknowledged as a contributor of plants 62.

Unfortunately, there is a wide gap between developed and developing nations such as India on patenting the products. For example, out of the 3,125,603 patents filed in 91 countries, only 301,177 or 9.6% are registered in developing countries while the rest is in industrialized countries. Of these, only 0.2% of the total and 2.3% of those registered in developing countries belong to residents. In addition, 97.7% of the total patents filed thus far are in the name of non-residents, who apply solely to control export markets in developing countries 63. Developing nations and many scientists who want to exploit medicinal plants demand more specific rules about the recording of nationality of samples and sharing of their benefits between the nations of origin, the inventor, and the commercial sponsors. Some developed nations are not inclined to accept such provisions. These conflicts have frustrated many scientists who believe that natural products remain the most promising source for new drugs. To mitigate such conflicts and gear up to find out new sources for drugs, the representatives of 188 nations at Kuala Lumpur Conference in 2004 agreed to try to build such a framework that would be acceptable to all signatories and thus the proposed framework will be placed for consideration at the next meeting in 2006 going to be held in Brazil 60.

Besides government agencies, there are numbers of stakeholders ranging from herb gatherers, local middlemen, urban traders, wholesalers, manufacturers, exporters and herbal healers in the medicinal plants trade sector. The marketing system in medicinal plants sector is largely unregulated and inequitable 4. The medicinal plant collectors are generally the marginal farmers and laborers. They get cash income to meet their basic requirements for food, health and children education by selling medicinal plants 42. They are often unaware about the real market prices of many medicinal plant species. Generally, in medicinal plants sector, there is a top down approach and even the many stakeholders at the bottom are not aware of the rising demand of their product and the availability of its market. In some villages of Chamoli district of Uttaranchal, the farmers had cultivated Kut (Saussurea costus) and Dolu (Rheum emodi) but they were unable to sell them due to lack of knowledge on the marketing system. Conversely, many medicinal plant species are traded through illegal channels 42.

The other constraints in the medicinal plants sector are: 1) slow rate of production of many medicinal plants, 2) long gestation period, 3) shortage of suitable cultivation technology, 4) production of small quantity, 5) unscientific harvesting, 6) paucity of research on the high yielding varieties, 7) inefficient processing techniques, 8) fluctuation in demand and supply, 9) poor quality control procedures, 10) scarcity of good manufacturers, (11) poor marketing infrastructure, and 12) poor coordination among different stakeholders 13814515964. On many occasions, the wild medicinal plants are preferred by manufactures compared to the cultivated ones, as there is a general feeling that wild plant species contain better chemical contents. The variation in chemical contents also depends upon the harvesting seasons of species and different stages of species growth. The medicinal plant sector is largely less documented and inadequately regulated. The economy generated by this sector is therefore, not precise because of the enormous illegal trade. The economic benefits and management cost for wild populations are poorly estimated on several occasions 465.

In the National Five Year Plans of India, the medicinal plants sector has been identified as an integral part of the Indian System of Medicine and Homeopathy 67. In 1983, the National Health Policy recognized that the large stock of health manpower in Ayurveda, Siddha, Unani, Homeopathy and Naturopathy had not been adequately utilized; therefore, steps need to be taken to move towards a meaningful integration of the indigenous and modern systems of medicine 68. The Planning Commission and the National Medicinal Plants Board (NMPB) of the Government of India have prepared a policy document on the promotional and commercial aspects of the medicinal plants sector. In addition, the NMPB has prioritized 32 and Planning Commission has enlisted 24 medicinal plant species for research and development in order to meet the desired aim of the medicinal plant sector (Table 3). The Biodiversity Act 2002 has framed many rules for sustainable utilization of medicinal plants and to mitigate the chances of bio-piracy 69.

According to Uttaranchal state action plan, the Forest Department of the state will have to identify two major areas in each Forest Division; namely the conservation area and the developmental area. The conservation areas will be selected based on their rich medicinal plants diversity and marked for in-situ conservation and complete protection in the concerned Forest Division. In the developmental areas, apart from protection of the existing bio-resources, the medicinal plant species of the neighboring areas will also be introduced and cultivated at a large scale. The remaining areas in the Forest Division will remain open for sustainable harvesting of the medicinal plant species. A Joint Harvesting Team, composed of medicinal plants experts, Forest Department officials and some selected local people, will be constituted, which will decide the extent of annual harvesting of the desired medicinal plant species 70. The various policies at national and state level and their subsequent implementation will provide an opportunity in the advancement of medicinal plants sector. This model of conservation and cultivation of the medicinal plants may be useful for generating the raw material for the 'Herbal Industries' as well as for ensuring the conservation of the rare medicinal plants.

In India, many government and non-government organizations have had the focused attention on improving the medicinal plants sector (Table 5). Opportunities for funding have been created to assist the person who is willing to work and to build capacity of the medicinal plants sector. According to the mandate of NMPB, the projects may be submitted for funding within two major schemes: viz., a promotional scheme and a commercial scheme. The major thrust areas within the promotional scheme are: 1) survey and inventory of medicinal plants, 2) in-situ conservation and ex-situ cultivation of selected medicinal plants, 3) production of quality planting material, 4) diffusion of knowledge through education and communication, 5) promotion of global and domestic market system, and 6) strengthening research, development and man power. Within the commercial scheme, the major thrust areas are: 1) bulk production of medicinal plants and ensuring supply of quality planting material, 2) expansion of selected medicinal plants farming areas, 3) value addition in harvesting, processing and marketing of medicinal plants, and 4) developing innovative marketing mechanism.

Apart from the two major themes, the role of NMPB is to co-ordinate with the different ministries, departments, organizations, state and union territory Governments in order to develop and strengthen the medicinal plant sector. One of the major roles of NMPB is to make contacts with national and international organizations devoted to similar mandates and goals. A total of 35 State Medicinal Plants Boards have also been created by NMPB for the smooth functioning of the medicinal plants sector. Approximately 35,000 hectares of land has been selected and brought under cultivation under the supervision of NMPB for the large-scale farming of commercially important medicinal plants. One of the schemes of NMPB is a contractual farming in which any group, institution or person that possesses at least 3 years of experience in medicinal plants sector would be eligible to receive at least 30% financial assistance of the total project cost 71.

Ten years before establishment of NMPB (during 1992–93 financial years), a single project was launched to study the medicinal plants of the Himalayan region 72. During past one decade, there has been a considerable expansion in the Himalayan medicinal plants research as it is evident that many projects have been launched exclusively on the medicinal plants during that period. Of the total 4254 projects sanctioned by NMPB over past 5 years, 732 projects have been sanctioned to 11 hill states in northern India. All these projects are expected to strengthen the medicinal plants sector, to bridge the gaps and to meet the challenges in developing the sector. In addition to major funding organizations, the G.B. Pant Institute of Himalayan Environment and Development has sanctioned projects on the medicinal plants of northern India under the scheme of Ministry of Environment & Forests (Table 6). The Council of Scientific and Industrial Research is building up a Traditional Knowledge Digital Library, which will contain > 35,000 herbal medical formulations used in Ayurvedic system of medicine 69.