CONSERVATION

CONSERVATION OF MEDICINAL PLANTS: AN OVERVIEW

Medicinal plants are not new to us: their therapeutic significance is well studied and discussed. However, their significance as an integral element of the biodiversity is being realized in the forestry sector lately, as it is brought to light that about 85% of known and recorded medicinal plant diversity of the country is captured in forests and wild habitat. It is also being realized that, 82% of high consumption botanicals (>100 MT per annum) in trade originates from wild sources. This realization has consequently led to a widespread concern in the forestry sector about medicinal plant resources.

These medicinal plants are the true backbones of a wide range of local health traditions, in addition to the codified medical systems such as Ayurveda, Siddha, Unani and Homoeopathy. Several medicinal plants species constitute many classical drug formulations and hundreds of home remedies. Medicinal plants are largely put to use in 3 different forms: Curative, promotive and preventive.

While the general understanding of a medicinal plant is rooted in the use of a plant to cure a disease, it should be noted that more than two third of the total medicinal plant diversity is used for preventive and promotive uses, which usually go unnoticed. Such preventive and promotive use, which is more predominant than the curative uses, is seen in the form of routine practices amongst us for body care, dental care and eye care, and in the form of cosmetics and special applications for beauty care and many special preparations for overall healthcare. It is a traditional practice to use different medicinal plants for hygiene and sanitation, fumigation and water purification in a household. Communities have different modes of using specific medicinal plants during many rituals and customary observances, and in the form of season specific diet and special preparations during festivals and celebrations in a year.

Hundreds of home remedies and household formulations have been interwoven into the lifestyles of several local communities. Besides, there are region-specific and community-specific medicinal plant usages that have further broadened the health traditions. Added to these, there are specialized fields of healthcare in the form of bone setting, antidotes and treatment of poisonous bites, traditional birth attendants, mother and post natal care and child care.

Status of medicinal plants in the wild and need for Conservation

That on one hand, these medicinal plants imply a flourishing pharmaceutical industry, raw drug trade and commerce, it is also true that, these plants hint at the possibility of high levels of pressures these might be undergoing. That is indeed true! The international pharmaceutical industry, considers the tropical medicinal plants as the source of rare drugs worth millions. The foremost pressure comes in the form of High levels of demand for the raw material of these lifesaving medicinal plants. This high demand sets in an interlocking loop affecting the overall survival of the species. It begins with high demand that results in high volume extraction, which might also trigger destructive methods of harvesting, to make up the produce in the least available time; such destructive harvesting measures, will invariably damage the population and subsequently the regeneration process of the species gets affected. Once the regeneration is affected, the total quantum of raw material available from a population also gets affected.

To compound the situation, not many raw drugs in the country originate from cultivated sources. Of the 178 medicinal plants species that register high volume trade of >100MT per year, only 36 are found to be entirely sourced from cultivation. Among these 36, only 4 species including, Isabgol, Senna, Henna, Aswagandha register large scale cultivation in the country, while acreage details of others are not available. It also brings to light that, besides these 4 species, Muskdana (Abelmoschus moschatus), Sweet flag (Acorus calamus), Adhatoda zeylanica, Aloe (Aloe barbadensis), Aswagandha (Withania somnifera), whose agro-technology practices are stabilized, have already entered into local agricultural systems.

The case of Amla, (Goose berry, Emblica officinalis) is worth mentioning, whose cultivation is seen in sizeable plantations in north India. The Amla growers association claims that the acreage of Amla plantations is about 70,000 ha. However, it is interesting to note that, only about 60% of the total produce from these plantations is used by the medicinal industry, while the rest goes for culinary preparations such as pickles, candies, jam and juice.

Species such as Neem, Tulsi, Coleus, Long Pepper, Sweet Basil, and Guggul are found in sizeable cultivation while common spices and condiments such as Black Pepper, Cinnamon, Clove, Nutmeg, Cardamom, and Coriander originate from cultivated sources. Apart from these examples, medicinal plants cultivation for supply of raw material for pharmaceutical industry is too fragmented and seen only on small holdings.

Thus, it only tells that, all is not well with medicinal plants, while many of them being subjected to different kinds of threats, often affecting the very survival. Several species are feared to be threatened, while the population size of some species is severely reduced and in certain cases the availability of the produce has become scarce.

This has set in an alarming situation, to register an urgent need to conserve the medicinal plants resource base. However, considering the large number of medicinal plant species under threat, the challenge is how to assign the conservation priorities.

Today many medicinal plants face extinction or severe genetic loss, but detailed information is lacking. For most of the endangered medicinal plant species no conservation action has been taken. For example, there is very little material of them in genebanks. Also, too much emphasis has been put on the potential for discovering new wonder drugs, and too little on the many problems involved in the use of traditional medicines by local populations.

For most countries, there is not even a complete inventory of medicinal plants. Much of the knowledge on their use is held by traditional societies, whose very existence is now under threat. Little of this information has been recorded in a systematic manner. Besides the identification and selection of medicinal plants for use in health services, there is the potential that plants hold as an inexhaustible reservoir for the identification and isolation of useful chemical compounds for syndromes such as AIDS, for which there is yet no known cure.

In the light of this situation, WHO, IUCN, and WWF decided that it would be timely to collaborate in convening an International Consultation on the conservation of medicinal plants, bringing together leading experts in different fields to exchange views on the problems, determine priorities and make recommendations for action. The experts at the meeting included administrators and policy-makers in health and conservation, and covered the disciplines of ethnomedicine, botany, education, pharmacology, nature conservation and economics. For IUCN and WWF, this meeting was an important part of their Plant Conservation Programmes.

Conservation of species broadly categorised into mainly two parts i.e. In-situ conservation and Ex-situ conservation.

Ex-situ conservation

Ex-situ conservation means literally, "off-site conservation". Ex situ conservation is the conservation and maintenance of samples of living organisms outside their natural habitat, in the form of whole plants, seed, pollen, vegetative propagules, and tissue or cell cultures.  It is the process of protecting an endangered species of plant or animal outside its natural habitat; for example, by removing part of the population from a threatened habitat and placing it in a new location, which may be a wild area or within the care of humans. While ex-situ conservation comprises some of the oldest and best known conservation methods, it also involves newer, sometimes controversial laboratory methods.

Ex situ conservation has several purposes:

• Rescue threatened germplasm.
• Produce material for conservation biology research.
• Bulk up germplasm for storage in various forms of ex situ facility.
• Supply material for various purposes to remove or reduce pressure from wild collecting.
• Grow those species with recalcitrant seeds that cannot be maintained in a seed store.
• Make available material for conservation education and display.
• Produce material for reintroduction, reinforcement, habitat restoration and management.

These ex situ collections of living organisms (living collections, seed banks, pollen, vegetative propagules, tissue or cell cultures) need to be managed according to strict scientific and horticultural standards to maximise their value for conservation purposes. Thus they need to be correctly identified, documented and managed and an efficient information management system put in place. Integrated conservation management can also ensure that ex situ collections can support in situ conservation, through habitat restoration and species recovery.

In-situ Conservation

In-situ conservation is on-site conservation or the conservation of genetic resources in natural populations of plant or animal species, such as forest genetic resources in natural populations of tree species. It is the process of protecting an endangered plant or animal species in its natural habitat, either by protecting or cleaning up the habitat itself, or by defending the species from predators. It is applied to conservation of agricultural biodiversity in agroecosystems by farmers, especially those using unconventional farming practices.

One benefit of in-situ conservation is that it maintains recovering populations in the surrounding where they have developed their distinctive properties. Another is that this strategy helps ensure the ongoing processes of evolution and adaptation within their environments. As a last resort, ex-situ conservation may be used on some or all of the population, when in-situ conservation is too difficult, or impossible.

Conservation Method