CONSERVATION AND PRODUCTION OF
TRADITIONAL MEDICINAL PLANTS IN HOME GARDENS: THE CASE OF ETHIOPIA
By:
Zemede Asfaw
Department of Biology, Addis Ababa University,
P.O. Box 3434, Addis Ababa, Ethiopia
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ABSTRACT
The role of the farming system of the home garden in maintenance, production, conservation and utilization of traditional medicinal plant resoources was studied. Survey data on home gardens in Ethiopia were inspected with special focus on their contribution to traditional medicine. The plants species with medicinal value wewre categorically examined to reflect on the level of popularity and use by families/communities. Of the species purposely maintained in Ethiopian home gardens, those cultivated primarily their medicinal value accounted for about 6% while, about30% were cultivated primarily for food (spices/herbsetc). A number of common garden weeds and live ence species also have medicinal use Parallelism between the traditional modern healing systems pertaining to the hierarchical nature and medicines is described. The medicinal flora of the home garden is more improtant for safe home - neighbouring level treatment executed by mothers and elderly community memnbers, while professionl traditional healers useually attend to more serious health problems using plants material mainly obtined secretly from amont those growing wild in secluded places. Prospects for optimizing the use fo the existing home garden medicinal flora, gradusl incorporation fo suitable wild species, setting up special medicinal plants gardens, and other options are discussed. The advantages offered by home gardens are perceived from the view points of biodiversity and indigenous innovations plus vorizing the medicinal plant industry. Integration of different conservation approaches with a bias on home gardens is anticipated to result in comparative advantages in the development of the medicinal plants sector. The paper also emphasizes the special strategic role of the home garden for in-situ conservation of crops (on farm), wild relatives of crops and useful threatened systems. Regional and international cooperation would serve conservation and equitable resources and innovations through intellectual property rights and patent regimes. It is sustainable farming system, worthy of research and development efforts, is yet to be achieved to attract respect and courtesy of scientists, rural development groups and the national policy environment.
Key words: Home garden, medicinal plants, conservation, and production
INTRODUCTION
Home gardens are traditional farming systems wherein indigenous crops of various categories are regularly cultivated and new crips are recureited and domesticates. In the course of embracing different categories of plants for domestication and subsequent cultivation in home gardens, families/communities have developed diverse intuitive criteria to help their decision making. Some of the criteria for taking a plant into cultivation, in the home garden, must have included extent of satisfying basic needs, multiplicity of use, diverse agromorphologic features, safeness and whether the knowledge on he plants was public/open or individual/restricted. One of several motive forces for maintaining home gardens is provided by the medicinal value of plants that are essential components of home gardens in different parts of the world (Christianity 1990, Cabarello 1992, Zemede Asfaw and Ayele Nigatu 1995). The claim in Ethiopia becomes more founded upon extrapolating information on garden plants used in traditional medical lore (Mesfin Tadesse 1986, Gelahun Abate 1989, Mesfin Tadesse and Sebsebe Demissew 1992), and those of regional na dglonbal importance (Boulos 1983). Some plant species are purposely grown in home gardens for use in traditional medicine, a good number of he remainin species that are improtant in traditional remedy are plants grown primarily for non medicinal purposee. Boulos (1983), in his book on Medicinal Plants of North Africa, compiled some 50 cultivated medicinal plant species, almost all cultivated in Ethiopia home gardens, and about the same number (49 species) are included in Gelahun Abate's (1989) book titled "Etse Debdabe" (Letters on Plants or Communication on Plants).
The more significant medicinal use of home garden species is at the level of the family and the neighborhood while the wild "supermarket", as it is sometimes called, is a natural reservoir of many medicinal plants in addition to edible, utility and other categories which are mostly used in formulations of traditional healers.
There are problems of continuity and sustainability faced by the medicinal plants sector as a result of loss of taxa and cultures in the changing world. The resolution of the problems requires interventions geared to conservation and development of the biodiversity and associated indigenous innovations, practices and knowledge systems. This was brought up strongly in the Convention on Biological Diversity (CBD 1994), wherein conservation of indigenous useful plants through maintenance of indigenous taxa, innovations, practices and knowledge systems was discussed and legislated in Articles 8 and 9 on in - situ and ex - situ conservation in general and paragraph 8(j) on knowledge, innovations, and practices of indigenous and local communities in particular (CBD 1994). The home garden farming system with the indigenous plants maintained in and its environs and the associated innovations, practices and knowledge systems offers a special opportunity for implementing the relevant provisions of the Convention. Traditional medicinal plants found in developing countries also face problems of unjust exploitation by individuals and companies in the developed world through intellectual property rights and patent laws that fail to consider the rightful owners of the resources and associated knowledge.
Where as the cultivated medicinal plants are traditionally conserved on-farm, individually and collectively, medicinal plants that continued being used from the wild flora have been threatened by unsustainable resource use habits. There is a growing demand for medicinal plants which when seen together with the rate of destruction of natural habitats alludes to enhanced conservation and protection strategies. The home garden is a very strategic and ideal farming system of conservation, production and enhancement of medicinal plants with the associated indigenous knowledge. Concerted national, regional and global efforts are key elements in consolidating actions to improve the sector.
This paper focuses on the role home gardens play in Ethiopia, particularly as they relate to traditional medicinal plants and delivery of traditional medicine. The current contributions of home gardens are examined, gaps and constraints reviewed and conceivable interventions voiced in light of the potential and prospects. Protection and increased production of traditional medicinal plants in home gardens is discussed in the context of improving community health, family income and conservation of biological diversity together with the associated indigenous knowledge, innovations and practices.
SOURCE OF INFORMATION AND METHODS
This paper is mainly based on data recovered from previous studies, conducted over the past few years, on Ethiopian home gardens (see Zemede Asfaw 1992, Zemede Asfaw and Ayele Nigatu 1995, Zemede Asfaw and Zehurin Woldu 1997). Information retrieved from the National Herbarium about medicinal plants cultivated in home gardens has also been included. Personal experience on how the traditional healing process operates at the rural village level and plants featuring in the system was reconstructed and included in the discussion part. Traditional medicinal plants of Ethiopia reported in monographs and papers/articles (e.g. Jansen 1981, Mesfin Tadesse 1986, Gelahun Abatae 1989, Mesfin Tadesse and Sebsebe Demissew 1992) were screened to list out those found in home gardens. Examinations of home garden plants and traditional medicinal plants allowed the screening of the common medicinal plants of the home garden; including those that are found in its immediate environs to reflect on species used and believed to be important in Ethiopia's traditional health care system. Traditional medicinal plants that are common elements of the home garden flora were examined against the entire medicinal plants of Ethiopia, categorized and analyzed to show the current contribution of the farming system to conservation and production of medicinal plants. The analyses and discussions have been linked to relevant sections of the Convention on Biological Diversity.
RESULTS AND DISCUSSION
Medicinal Plants in Home Garden Farming System
Home gardens are small scale traditional farming systems practiced around the house. They are primarily for growing various crops for home consumption and on-farm conservation as well as for experimental planting of new recruits. Studies show that the agro biodiversity in tropical Africa, including Ethiopia, is highest near the home (Okigbo 1994). Traditionally families plant many species they considered useful close to their living quarters. Such observations have directed special focus on home gardens as strategic units for in-situ conservation of the agro biodiversity and for maintenance of indigenous knowledge, practices and innovations.
Depending on the agro ecology of the area, staple crops, supplementary crops, additives, tree crops and non food plants of various utility classes including medicine are grown in home gardens in tropical and subtropical areas of the world (Christanty 1990, Okigbo 1994, Cabarello 1992). In Ethiopia, home gardens range from non-existent, through rudimentary existence to well developed stages (Zemede Asfaw and Ayele Nigatu 1995). They are very versatile in their uses so that their intensity, major purposes and productivity varies with agro ecology, locality and traditions and needs of social groups. It is also observed that experimental growing, maintenance of planting materials, seedling raising, on-farm conservation and improvement of crop through selection for specific traits are some of the rather subtly or keen purposes of traditional home gardens. Many garden crops are multipurpose and one of these purposes is medicinal value. Ensete ventricosum is one of the most frequent indigenous home garden crops which is valued as food, fodder, fibre, medicinal and general utility crop. It is reported that twelve out of forty-two and seventeen out of forty - three clones of this species have medicinal value in Sidamo and Gurage, respectively (Ansketch Woldentensaye 1997.
It is speculated that home gardening in Ethiopia is probably as old as agriculture itself, which is estimated to have started at about 7000 years ago (Ehret 1979, Brandt 1984). A study made in southern Ethiopia (Zemede Asfaw and Zerihun Woldu 1997) showed that the home garden is by far a place for production of food crops as revealed by the family nutritional calculus that surfaced out when the nutritional complement of the species grown together was taken into account. Though the primary target of home gardens in human nutrition, medicinal functions are also embodied. Out of 30 most frequent crops in 18 randomly selectd homes gardens, 15 (50%) are used medicinally, showing that crop clusters of home gardens have multiple functions, food and medicine being the most frequent combinations for rural communities.
Home Garden Medicinal Plants in Traditional Health Care
Crop species primarily cultivated for purposed of medicinal purposes in home gardens (Tables 2) are presented to reflect the level of popularity. In addition to about 6% of those primarily considered medicinal, traditional medicinal plants are obtained from all crop categories but more so from spices and herbs, fragrances, stimulants, fruits and others. Most of the medicinal plants of home gardens are meant for instant use and their medicinal effect may sometimes depend on the vitamins and minerals that they supply. During a recent study in a semi - urban town in southwestern parts of Ethiopia, Families affirmed that about 75% of Ruta chalepensis and Cariandrum sativum they harvest from home gardens were either used or sold for medicinal purposes. Some of the traditional medicines are actually given with food or tea and some times serve like the prophylactics of modern medicine.
The medicinal plants frequently used by rural families are obtained from plants purposely cultivated in the home garden primarily for their medicinal value, those cultivated primarily for non - medicinal use but widely known to have additional value as medicine when the need arises and those that occur in gardens as weeds and live plants of garden fences. A large number of the medicinal flora that occurs spontaneously in the general area of the homestead outside the garden proper and far out. The medicinal value of some crop species (e.g. Ruta chalepensis, Foenicuulum vugare, Allium sativum, Lepidium sativum, Nigella sativa, Zingiber officinale, Thymus serulatus, Coffea arabica, Linum usitatisimum, Rhammus pronoides, Citrus aurantifolium, Cucurbita pepo, Ensete ventricosum, Carica papaya) is a common public knowledge in Ethiopia as these are frequently prescribed by ordinary people for a variety of minor health complaints. Animal health and pest controls is also simple and are attended by the low level medication at family and neighborhood levels.
Medicinal Plants and the Traditional Healing System
Hierarchy and Ethics in Traditional Medical Delivery
There is a parallelism in the medical ethics adopted by the traditional and modern delivery and healing systems, both in medication and operation. It appears that the toxicity of the plants, the seriousness of the health problem for which medication is sought and the application procedure determine both the hierarchy of medication and the class of plants. Treatment of the health problems of domestic animals follows the first line of operation. The first line can be seen to be analogous to minor drugs sold openly or to simple first aid like treatments of modern medicine while the second is analogous to drugs sold and used under strict prescription by doctors or administered under intensive medical care. This is probably one reason, in addition to knowledge monopoly and protection from law, for traditional medicinal medicine being secrete and mythical in many instances while open and clear at family level. The professional knowledge is not available to all, but only passed over to one of the healer's trustworthy relations through long time training under an apprenticeship system. The medicinal plants of the home garden are, by contrast, well known to many, and their proper prescription is usually sought from amateur mothers and elderly women.
The delivery system, which is handled by people of different levels of competence is also structured like that of modern hospital system. At the lowest level mothers take care of simple medication within the family. If they find it not easy to handle, a more competent woman or a man in the neighborhood is looked for and usually there is no charge at this level. If it is found to be serious by the village level, it is automatically referred to a specialist healer, usually a man who uses combinations of plants which only he knows and does not show to any one, but only to his close relation, to whom he is going to pass his wisdom. This level of medication is usually paid for either in cash or kind unless one is a relative or the healer. It may also be that some of the plants that he uses are deadly poisonous and he has to handle them carefully by keeping them secret and prescribing the right amount of doses. Growing such plants in home gardens may not be advisable for the simple reason that desperate people may harm themselves through self of amateur treatment. No one except w well recognized healer would dare to treat a person bitten by a mad dog or one with jaundice. In my own village the hierarchy in healing went from my mother (frequent family healer), to Hadadem (village healer) and Abiyendinget (the specialist healer for many villages as a kind of referral system). The plants used, the combinations, the problems attended to the level of secrecy involved vary with the healing level as depicted in Fig 2. The level of specialization and the difference in gender roles comes out to a clear view in this scheme, which has been reconstructed by visualizing the traditional system.
Home garden Medicinal Plants in the Hierarchy of Traditional Healing
The plants of the Home Garden were more that often used by the rather informal and amateur healing system exercised at the family and neighborhood levels. The medicinally well-known home garden plants are frequently used by the family level treatment and after being sold in the open market, usually for non-medicinal purposes. Women are almost the sole venders of these aromatic plants also used as medicinal. In traditional lifestyle the kitchen and the hospital looked so close as many of the pot herbs and spices are prescribed for some health complaints. The mother is the food maker and the family doctor, while few elderly women in the village act as village doctors. The role of traditional medicinal plants is visualized in this hierarchical medical delivery structure, which reveals differences in the plants and the level of competence in dealing with serious health matters.
The class of medicinal plants delivered by mothers and semi-specialist women in the village are mostly obtained from the crops of the garden. These are mostly for instant use, usually for external applications and use with food and tea. Such plants usually have one- to - one correspondence with a health problem. Thus mothers prescribe rue, garlic, basil and others for specific health complaints, which they apply by including in food, tea, soups or smoke, rub the skin, or smear the affected part as the case may be. The plants frequently used by specialist healers are usually obtained from secluded places and administered after an elaborate diagnosis and complex mixing an intensive treatment and by the specialist himself.
Efforts Geared at Traditional Medicinal Plants
These are studies conducted on various aspects of traditional medicinal plants in Ethiopia. However, well focused studies targeted to both research and development are still missing. The documentation of traditional medicinal plants appears to be in a better stage with the recent publication of four volumes of flora of Ethiopia and extensive collection of plants throughout the country. However, these collections do not have sufficient ethno botanical information as the collections did not primarily focus at documenting medicinal plants. Over the years, attempts have been made to recover the species with medicinal value as could be seen in Mesfin Tadesse 1986, Gelahun Abate 1989, mesfin Tadesse and Ssebsebe Demissew 1992. The utilization aspect has also been studied by the department for traditional medicine while conservation is to be seen as part of forest and nature conservation in some zones. The GEF supported project on a dynamic farmer-based approach to the conservation of Ethiopia's plant genetic resources, which envisages establishment of botanic gardens in project sites, is being implemented by the Biodiversity institute. The recent report indicates that there are attempts to demarcate places for botanic gardens at two sites. Since Ethiopia is a big country with diverse agro ecologies, these efforts are far too shorter than the needs. The strategic role of the home garden has for long escaped sights of appropriate development/conservation schemes and has not been targeted for modern conservation production of traditional medicinal plants. A project, now at the stage of writing a proposal, is being initiated in the country and it appears to be multidisciplinary and keen on the role of home gardens.
Constraints and Gaps in Conservation and Use of Traditional Medicinal Plants
Many plants used in traditional medicine are harvested from natural stands and some of these are becoming more and more limited in distribution as a result of agricultural expansion and habitat shrinkage (e.g. Hagenia abyssinica) and overuse at least in some cases (e.g. Taverniera abyssinca, clausiena anisata). A major current concern, therefore, is to enhance not only conservation but also production of medicinal plants. The potential of home gardens in the conservation and use of medicinal plants is considered high and would need to be integrated with other options. While some medicinal plants are cultivated for other purposes and do not as such face conservation problems, those that used to be common weeds in gardens are being abandoned as a result of intensification of the home garden farming system. A major observation made during the study was that plants cultivated primarily for their medicinal value are very few and the traditional medical lore depends to a great extent on wild grown plants. It appeared that the role of home gardens for continuously domesticating new plants, the medical efficacy of which is acknowledged by the society, has not been encouraging being related to the knowledge system and the healing practice that evolved over generations. The other problem is connected with the pre eminent function of the home garden which is more of food and economy oriented in addition to the fact the at the space is mostly limited and cannot be expanded to incorporate many new plants. Modern agriculture failed to see the home garden as a production and conservation facility of the traditional agricultural system. The new movement in the country for crop on-farm in-situ conservation will ultimately lead to the recognition of the value of home gardening for conservation of the agro biodiversity including wild and weedy crop relatives.
Need for Improvement of the Traditional Medicinal Plants Sector
In order to improve the situation of medicinal plants in Ethiopia, a number of options come to mind. These can be seen under production, conservation, improvement, processing and exchange systems. The home gardens will be a good target of attention to positively respond to many of the needs of traditional health care system that exists in Ethiopia today. One very important strategy, therefore, will be to enhance the farming system of the home garden to enable more production and effective conservation of medicinal plants. However, for a comprehensive approach the medicinal plants industry would need to consider other options of cultivation and conservation outlined below as well as improvement of the delivery system to include market incentives.
Enhancement of Cultivation of Medicinal Plants in Home Gardens
In order to enhance the role of traditional medicinal plants in the community, the home gardens are central targets for in-situ conservation of existing species and ex-situ conservation of wild species through domestication and cultivation. Many home gardens in Ethiopia are not optimally used with respect to space and niching the growth forms. In some areas the space surrounding the house is not utilized while in others there are unused spaces. Even well developed home gardens can find some places for important medicinal plants if families are convinced about their uses in domestic health care and income generation. It is possible to fit many new medicinal plants into the home garden faming system. However, there may be space limitation in some of the already overburdened home gardens.
Farmers usually plant few plants on experimental basis closely observing them before production. This testing period allows seeing if the new plants are in some way detrimental to other garden crops. Since some wild plants are disease reservoirs, domestication of wild medicinal plants should be handled professionally with the assistance of farmers. Furthermore, it should be noted that some wild plants are adapted to marginal poor soils and fail to fit in the fertile home garden environment. Unworked plots within the home garden can be devoted for growing wild medicinal plants for gradual domestication. The introduction of new medicinal plants into the home garden must also pay particular attention to ethical issues concerning toxicity.
Enhancement of Traditional Medicinal Plants by other Means
The home garden is one major avenue for enhancement of conservation and use of medicinal plants. However, since medicinal plants are many in number and also very diverse in their botany and ecology, other conservation and production methods including those discussed below need to be motivated.
Establishment of Small - Scale Special Medicinal Plant Gardens
Some traditional healers have started establishing small compound gardens where they grow most of the medicinal plants they need for their work. Below ( Fig 3) is a sketch and description of one such garden seen in the compound of a nature clinic in Addis Ababa. This is kindly shown to us by the owner, who has already set a good example not only in the large number of plants he has managed to grow continuously but also in the style of cultivation he adopted. Most of the medicinal plants are grown in a plot wherein the pattern of planting is more or random and there is no weeding so that the plot appears like a natural stand wherein weedy medicinal plants get incorporated spontaneously and many of them regenerate naturally. In another plot in the same compound other species are planted with vegetables under intensive care. At the back of the house there are profusely growing medicinal plants including Achyranthes aspera, Ricinus communis, Tropaoleum sp. and Ipomea sp. which the healer uses in his formulations. The compound has many other species growing rather informally, thus sufficiently increasing the diversity of medicinal plant without having to depend on nature alone, but optimizing the new nature cure drive.
There are many traditional healers in Addis Ababa but most of them use plants mostly collected from nature. Only some of them are keen in cultivating some plants that are common components of traditional home gardens. The plants observed in the compound of one well-known healer were Ruta Chalepensis, Laggera sp., Ocimum lamifolium and Vernonia amygdalina. Use of medicinal plants from nature by professional healers cannot be sustainable particularly when the species is rare and its habitat is narrow. Women by contrast cannot grow more of the traditional home garden crops partly as spices and partly as medicines even in urban areas like Addis Ababa.
In one rural home garden 20 of the species grown for various purposes are known to have medicinal value. Together with the medicinal species of the fences and garden weeds the number available to families is considerable, but the use is limited by the healing system. Even in this village the preparations of the professional traditional healer are obtained from his own garden or elsewhere. When the healer has to prepare the medicine from the customers garden he makes sure that he goes alone in the garden and comes back with meshed up plant material such that no one would know what plant it came from.
Conservation of Traditional Medicinal Plants in Nature Reserves
Some traditional plants may have to conserved in - situ in their natural habitats due to difficulty for domestication and management or failure to produce the desired amount and quality of the active principles under cultivation (Franz 1993).
Large Scale medicinal Plant Farms
Depending on the level of development of the medicinal plant industry, large-scale private medicinal plant farms can be established to produce plant material for analysis. This will turn out to be a lucrative business since mostly vegetative material (leaves, etc.) are harvested, without having to wait for fruiting.
In - situ Conservation of the Biodiversity of medicinal Plants in Special Places
Medicinal plants can also be conserved by ensuring and encouraging their growth in special places, as they have been traditionally, within the cultivated landscape including in places of worship (churches, mosques, grave yards, etc.), sacred grooves, farm margins, river banks, roadsides, rocky outcrops in fields, trees in fields/villages, live fences of gardens and fields, etc., where native species thrive. It may also be possible to conserve tree and shrub species of medicinal plants by using them in afforestation and hillside plantation programmes of re - vegetating hillsides.
Conservation of Medicinal Plants by Conventional Ex-Situ Methods
Alongside the above methods of conservation and conventional ex-situ methods including gene banks, botanical gardens and field gene banks should be considered.
Domestication/Cultivation of Medicinal Plants in Home Gardens
Most medicinal Plants of Ethiopia and the world at large are wild. The development of the medicinal plants industry without endangering biological diversity can only come if the important wild medicinal plants are domesticated. This is what has been arrived at many international forums (Franz 1993). Three main advantages of this strategy are conservation, large-scale production and standardization of products through growth manipulations and genetic improvement. This will also preserve the indigenous knowledge on the conservation and use of medicinal plants. Though domestication of wild species is a tedious process, it has to be made. To overcome this problem, the traditional knowledge and practice could be useful and should be adopted through a partnership with local farmers and farming communities. Given the long tradition in Ethiopia of crop domestication and introduction, the domestication of selected wild medicinal plants will not be a problem to farmers as long as they are convinced about their uses. Efforts to domesticate wild growing medicinal plants in home gardens can adopt the following procedure (Franz 1993) in addition to practices of local farmers.
* Study of the natural habitat, botany/ethnobotany, ethnomedicine, soil, climate, growing, natural distribution and propagation (much information from indigenous knowledge) of important wild - grown medicinal plants
* Collection of wild grown plants, seeds and phytochemcal screening
* Plant propagation, vegetative/seed. Plantlet cultivation, in-vitro methods
* Genetic improvement, variability, selection, breeding, phytochemical investigation
* Cutivation treatments, growing site, fertilization, crop maintenance and cultivation
* Duration of cultivation, harvest/post-harvest handling, phytochemical control of produce
* Apply procedure for introduction of new crops blended with farmer methods
Economic evaluation and calculations
The cultivation of newly domesticated medicinal plants and introduced ones will be essential in order to increase the contribution of medicinal plants in the health care system of Ethiopia.
The Path Ahead
In Ethiopia, home gardens are important traditional innovations much concerned with the continuous provision of food and other basic necessities and home gardening is a ling standing practice. Most of the crops maintained on-farm are also indigenous, but the system has also been dynamic, introducing exotic plants found to be useful, suitable and well fitting into the culture and the ecology. However, their critical importance in food security and in-situ conservation of the agro biodiversity of traditional crops and associated wild and weedy relatives seem to have eluded the necessary emphasis by modern agricultural and community development interventions. The modern agricultural system has not been able to appreciate the totality of the traditional system and the crops as a viable system for promotion. The modern system works hard to produce few high yielding international crops based on marketed seeds, while traditional home gardening is based on diversifying the tax to have little of everything which spreads the risks and maximizes the nutritional diversity being concerned not only for people but also for animals. Until modern agricultural systems consider home gardens viable and become committed to develop appropriate enhancement strategies, other parties such as non-governmental organizations can engage in participatory programmes. They can study the system, learn from it and try to positively influence it without pushing for monoculture gardens, as has been the practice earlier on. In Welayita, it was observed that with growing urbanization home gardens are evolving to a near monoculture of few tree crops (Zemede Asfaw and Zerihun Woldu 1997), being influenced by promotion from the modrn agricultural sector which emphasized on the financial returns, disregarding the diversity of products, nutritional value and the primary home-use functions.
The conservation of traditional medicinal plants must be looked at in a holistic manner so that not only in-situ but also ex-situ options are motivated. Such an approach would automatically serve the objectives envisaged by Article 8(j) of the Convention on Biological Diversity (CBD 1994, BIOTHAI and GRAIN 1997). This article of the convention call for respect, maintenance and preservation of knowledge, innovations and practices of indigenous and local communities embodying traditional lifestyles relevant for the conservation and enable use of biological diversity and promote wider application with approval and involvement of the holders of such knowledge, innovations and practices and encourage equitable sharing of benefits arising from utilization of such knowledge, innovations and practices. The article draws attention to the protection of many rights (IUCN 1993, BIOTHAI and GRAIN1997), and instruments developed following the wishes of the Convention should submit to its basic doctrine. When it comes to application, it is not advisable to single out this paragraph since conservation should be seen like a package of in-situ and ex-situ which are given separately for the purpose of improving clarity for implementation. The article assumes that there will be honesty and harmony in regional and global collaborations to preserve and use biological diversity and indigenous innovations in the best interest of collaborating parties. The main issue is protection of biodiversity an associated knowledge systems from individualization of benefits by such things as intellectual property rights and patent laws that exclude those who generated and maintained the resources and the knowledge through generations.
RECOMMENDATIONS
The home gardens in Ethiopia have been important in production and conservation of such critical plant species as medicinal plants. They allow for integration of medicinal plants with other categories of plants offering multiple uses. A plant which has medicinal and other uses is most likely to be quickly accepted and cultivated in home gardens by farming communities as it allows them to get multiple advantages as has been the case traditionally. A food plant with medicinal property will attract even better attention of farming families because of the added fact that there will be less risks of toxicity (the part used as medicine may be toxic) when used as medicine. Conservation and production of medicinal plants primarily in home gardens must be given priority along with other conservation options and market incentives. It is therefore imperative that the following recommended steps be realized.
* Recognize home gardens as important places for conservation and production of important categories of plants such as medicinal plants and promote their intensification and enhancement,
* Study important wild growing medicinal plant with a vision for domestication in home gardens and subsequent cultivation through step by step strategy,
* Compile and build a compendium of information on each tax on of interest
* Start a two-way awareness creation scheme for development agents/NGOs and local people learning from each other,
* With the local people, identify wild-growing medicinal plants that can fit into the home garden agro-culture, considering botanical, social and ethical/factors,
* Classify the plants for short, medium and long-term domestication/cultivation in home gardens of the main agro ecological zones,
* learn from the people who have knowledge on uses of propagation methods,
* Activate conservation of medicinal plants in all possible ways in a holistic approach and for medicinal plants not recommended for cultivation in home gardens ensure implementation of one or more of the methods outlined,
* Identify families who will be willing to start experimental planting of selected species in their home gardens and initiate actual domestication and cultivation,
* For all medicinal plants in home gardens create market incentives so that the production level of families will rise,
* Develop technologies for crude extracts of medicines with keen visions for improvement to modern pharmaceutical formulations,
* Strengthen faithful regional and global cooperation to ensure conservation, development and equitable sharing of the benefits that accrue from traditional medicinal plants.
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By:
Zemede Asfaw
Department of Biology, Addis Ababa University,
P.O. Box 3434, Addis Ababa, Ethiopia
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ABSTRACT
The role of the farming system of the home garden in maintenance, production, conservation and utilization of traditional medicinal plant resoources was studied. Survey data on home gardens in Ethiopia were inspected with special focus on their contribution to traditional medicine. The plants species with medicinal value wewre categorically examined to reflect on the level of popularity and use by families/communities. Of the species purposely maintained in Ethiopian home gardens, those cultivated primarily their medicinal value accounted for about 6% while, about30% were cultivated primarily for food (spices/herbsetc). A number of common garden weeds and live ence species also have medicinal use Parallelism between the traditional modern healing systems pertaining to the hierarchical nature and medicines is described. The medicinal flora of the home garden is more improtant for safe home - neighbouring level treatment executed by mothers and elderly community memnbers, while professionl traditional healers useually attend to more serious health problems using plants material mainly obtined secretly from amont those growing wild in secluded places. Prospects for optimizing the use fo the existing home garden medicinal flora, gradusl incorporation fo suitable wild species, setting up special medicinal plants gardens, and other options are discussed. The advantages offered by home gardens are perceived from the view points of biodiversity and indigenous innovations plus vorizing the medicinal plant industry. Integration of different conservation approaches with a bias on home gardens is anticipated to result in comparative advantages in the development of the medicinal plants sector. The paper also emphasizes the special strategic role of the home garden for in-situ conservation of crops (on farm), wild relatives of crops and useful threatened systems. Regional and international cooperation would serve conservation and equitable resources and innovations through intellectual property rights and patent regimes. It is sustainable farming system, worthy of research and development efforts, is yet to be achieved to attract respect and courtesy of scientists, rural development groups and the national policy environment.
Key words: Home garden, medicinal plants, conservation, and production
INTRODUCTION
Home gardens are traditional farming systems wherein indigenous crops of various categories are regularly cultivated and new crips are recureited and domesticates. In the course of embracing different categories of plants for domestication and subsequent cultivation in home gardens, families/communities have developed diverse intuitive criteria to help their decision making. Some of the criteria for taking a plant into cultivation, in the home garden, must have included extent of satisfying basic needs, multiplicity of use, diverse agromorphologic features, safeness and whether the knowledge on he plants was public/open or individual/restricted. One of several motive forces for maintaining home gardens is provided by the medicinal value of plants that are essential components of home gardens in different parts of the world (Christianity 1990, Cabarello 1992, Zemede Asfaw and Ayele Nigatu 1995). The claim in Ethiopia becomes more founded upon extrapolating information on garden plants used in traditional medical lore (Mesfin Tadesse 1986, Gelahun Abate 1989, Mesfin Tadesse and Sebsebe Demissew 1992), and those of regional na dglonbal importance (Boulos 1983). Some plant species are purposely grown in home gardens for use in traditional medicine, a good number of he remainin species that are improtant in traditional remedy are plants grown primarily for non medicinal purposee. Boulos (1983), in his book on Medicinal Plants of North Africa, compiled some 50 cultivated medicinal plant species, almost all cultivated in Ethiopia home gardens, and about the same number (49 species) are included in Gelahun Abate's (1989) book titled "Etse Debdabe" (Letters on Plants or Communication on Plants).
The more significant medicinal use of home garden species is at the level of the family and the neighborhood while the wild "supermarket", as it is sometimes called, is a natural reservoir of many medicinal plants in addition to edible, utility and other categories which are mostly used in formulations of traditional healers.
There are problems of continuity and sustainability faced by the medicinal plants sector as a result of loss of taxa and cultures in the changing world. The resolution of the problems requires interventions geared to conservation and development of the biodiversity and associated indigenous innovations, practices and knowledge systems. This was brought up strongly in the Convention on Biological Diversity (CBD 1994), wherein conservation of indigenous useful plants through maintenance of indigenous taxa, innovations, practices and knowledge systems was discussed and legislated in Articles 8 and 9 on in - situ and ex - situ conservation in general and paragraph 8(j) on knowledge, innovations, and practices of indigenous and local communities in particular (CBD 1994). The home garden farming system with the indigenous plants maintained in and its environs and the associated innovations, practices and knowledge systems offers a special opportunity for implementing the relevant provisions of the Convention. Traditional medicinal plants found in developing countries also face problems of unjust exploitation by individuals and companies in the developed world through intellectual property rights and patent laws that fail to consider the rightful owners of the resources and associated knowledge.
Where as the cultivated medicinal plants are traditionally conserved on-farm, individually and collectively, medicinal plants that continued being used from the wild flora have been threatened by unsustainable resource use habits. There is a growing demand for medicinal plants which when seen together with the rate of destruction of natural habitats alludes to enhanced conservation and protection strategies. The home garden is a very strategic and ideal farming system of conservation, production and enhancement of medicinal plants with the associated indigenous knowledge. Concerted national, regional and global efforts are key elements in consolidating actions to improve the sector.
This paper focuses on the role home gardens play in Ethiopia, particularly as they relate to traditional medicinal plants and delivery of traditional medicine. The current contributions of home gardens are examined, gaps and constraints reviewed and conceivable interventions voiced in light of the potential and prospects. Protection and increased production of traditional medicinal plants in home gardens is discussed in the context of improving community health, family income and conservation of biological diversity together with the associated indigenous knowledge, innovations and practices.
SOURCE OF INFORMATION AND METHODS
This paper is mainly based on data recovered from previous studies, conducted over the past few years, on Ethiopian home gardens (see Zemede Asfaw 1992, Zemede Asfaw and Ayele Nigatu 1995, Zemede Asfaw and Zehurin Woldu 1997). Information retrieved from the National Herbarium about medicinal plants cultivated in home gardens has also been included. Personal experience on how the traditional healing process operates at the rural village level and plants featuring in the system was reconstructed and included in the discussion part. Traditional medicinal plants of Ethiopia reported in monographs and papers/articles (e.g. Jansen 1981, Mesfin Tadesse 1986, Gelahun Abatae 1989, Mesfin Tadesse and Sebsebe Demissew 1992) were screened to list out those found in home gardens. Examinations of home garden plants and traditional medicinal plants allowed the screening of the common medicinal plants of the home garden; including those that are found in its immediate environs to reflect on species used and believed to be important in Ethiopia's traditional health care system. Traditional medicinal plants that are common elements of the home garden flora were examined against the entire medicinal plants of Ethiopia, categorized and analyzed to show the current contribution of the farming system to conservation and production of medicinal plants. The analyses and discussions have been linked to relevant sections of the Convention on Biological Diversity.
RESULTS AND DISCUSSION
Medicinal Plants in Home Garden Farming System
Home gardens are small scale traditional farming systems practiced around the house. They are primarily for growing various crops for home consumption and on-farm conservation as well as for experimental planting of new recruits. Studies show that the agro biodiversity in tropical Africa, including Ethiopia, is highest near the home (Okigbo 1994). Traditionally families plant many species they considered useful close to their living quarters. Such observations have directed special focus on home gardens as strategic units for in-situ conservation of the agro biodiversity and for maintenance of indigenous knowledge, practices and innovations.
Depending on the agro ecology of the area, staple crops, supplementary crops, additives, tree crops and non food plants of various utility classes including medicine are grown in home gardens in tropical and subtropical areas of the world (Christanty 1990, Okigbo 1994, Cabarello 1992). In Ethiopia, home gardens range from non-existent, through rudimentary existence to well developed stages (Zemede Asfaw and Ayele Nigatu 1995). They are very versatile in their uses so that their intensity, major purposes and productivity varies with agro ecology, locality and traditions and needs of social groups. It is also observed that experimental growing, maintenance of planting materials, seedling raising, on-farm conservation and improvement of crop through selection for specific traits are some of the rather subtly or keen purposes of traditional home gardens. Many garden crops are multipurpose and one of these purposes is medicinal value. Ensete ventricosum is one of the most frequent indigenous home garden crops which is valued as food, fodder, fibre, medicinal and general utility crop. It is reported that twelve out of forty-two and seventeen out of forty - three clones of this species have medicinal value in Sidamo and Gurage, respectively (Ansketch Woldentensaye 1997.
It is speculated that home gardening in Ethiopia is probably as old as agriculture itself, which is estimated to have started at about 7000 years ago (Ehret 1979, Brandt 1984). A study made in southern Ethiopia (Zemede Asfaw and Zerihun Woldu 1997) showed that the home garden is by far a place for production of food crops as revealed by the family nutritional calculus that surfaced out when the nutritional complement of the species grown together was taken into account. Though the primary target of home gardens in human nutrition, medicinal functions are also embodied. Out of 30 most frequent crops in 18 randomly selectd homes gardens, 15 (50%) are used medicinally, showing that crop clusters of home gardens have multiple functions, food and medicine being the most frequent combinations for rural communities.
Home Garden Medicinal Plants in Traditional Health Care
Crop species primarily cultivated for purposed of medicinal purposes in home gardens (Tables 2) are presented to reflect the level of popularity. In addition to about 6% of those primarily considered medicinal, traditional medicinal plants are obtained from all crop categories but more so from spices and herbs, fragrances, stimulants, fruits and others. Most of the medicinal plants of home gardens are meant for instant use and their medicinal effect may sometimes depend on the vitamins and minerals that they supply. During a recent study in a semi - urban town in southwestern parts of Ethiopia, Families affirmed that about 75% of Ruta chalepensis and Cariandrum sativum they harvest from home gardens were either used or sold for medicinal purposes. Some of the traditional medicines are actually given with food or tea and some times serve like the prophylactics of modern medicine.
The medicinal plants frequently used by rural families are obtained from plants purposely cultivated in the home garden primarily for their medicinal value, those cultivated primarily for non - medicinal use but widely known to have additional value as medicine when the need arises and those that occur in gardens as weeds and live plants of garden fences. A large number of the medicinal flora that occurs spontaneously in the general area of the homestead outside the garden proper and far out. The medicinal value of some crop species (e.g. Ruta chalepensis, Foenicuulum vugare, Allium sativum, Lepidium sativum, Nigella sativa, Zingiber officinale, Thymus serulatus, Coffea arabica, Linum usitatisimum, Rhammus pronoides, Citrus aurantifolium, Cucurbita pepo, Ensete ventricosum, Carica papaya) is a common public knowledge in Ethiopia as these are frequently prescribed by ordinary people for a variety of minor health complaints. Animal health and pest controls is also simple and are attended by the low level medication at family and neighborhood levels.
Medicinal Plants and the Traditional Healing System
Hierarchy and Ethics in Traditional Medical Delivery
There is a parallelism in the medical ethics adopted by the traditional and modern delivery and healing systems, both in medication and operation. It appears that the toxicity of the plants, the seriousness of the health problem for which medication is sought and the application procedure determine both the hierarchy of medication and the class of plants. Treatment of the health problems of domestic animals follows the first line of operation. The first line can be seen to be analogous to minor drugs sold openly or to simple first aid like treatments of modern medicine while the second is analogous to drugs sold and used under strict prescription by doctors or administered under intensive medical care. This is probably one reason, in addition to knowledge monopoly and protection from law, for traditional medicinal medicine being secrete and mythical in many instances while open and clear at family level. The professional knowledge is not available to all, but only passed over to one of the healer's trustworthy relations through long time training under an apprenticeship system. The medicinal plants of the home garden are, by contrast, well known to many, and their proper prescription is usually sought from amateur mothers and elderly women.
The delivery system, which is handled by people of different levels of competence is also structured like that of modern hospital system. At the lowest level mothers take care of simple medication within the family. If they find it not easy to handle, a more competent woman or a man in the neighborhood is looked for and usually there is no charge at this level. If it is found to be serious by the village level, it is automatically referred to a specialist healer, usually a man who uses combinations of plants which only he knows and does not show to any one, but only to his close relation, to whom he is going to pass his wisdom. This level of medication is usually paid for either in cash or kind unless one is a relative or the healer. It may also be that some of the plants that he uses are deadly poisonous and he has to handle them carefully by keeping them secret and prescribing the right amount of doses. Growing such plants in home gardens may not be advisable for the simple reason that desperate people may harm themselves through self of amateur treatment. No one except w well recognized healer would dare to treat a person bitten by a mad dog or one with jaundice. In my own village the hierarchy in healing went from my mother (frequent family healer), to Hadadem (village healer) and Abiyendinget (the specialist healer for many villages as a kind of referral system). The plants used, the combinations, the problems attended to the level of secrecy involved vary with the healing level as depicted in Fig 2. The level of specialization and the difference in gender roles comes out to a clear view in this scheme, which has been reconstructed by visualizing the traditional system.
Home garden Medicinal Plants in the Hierarchy of Traditional Healing
The plants of the Home Garden were more that often used by the rather informal and amateur healing system exercised at the family and neighborhood levels. The medicinally well-known home garden plants are frequently used by the family level treatment and after being sold in the open market, usually for non-medicinal purposes. Women are almost the sole venders of these aromatic plants also used as medicinal. In traditional lifestyle the kitchen and the hospital looked so close as many of the pot herbs and spices are prescribed for some health complaints. The mother is the food maker and the family doctor, while few elderly women in the village act as village doctors. The role of traditional medicinal plants is visualized in this hierarchical medical delivery structure, which reveals differences in the plants and the level of competence in dealing with serious health matters.
The class of medicinal plants delivered by mothers and semi-specialist women in the village are mostly obtained from the crops of the garden. These are mostly for instant use, usually for external applications and use with food and tea. Such plants usually have one- to - one correspondence with a health problem. Thus mothers prescribe rue, garlic, basil and others for specific health complaints, which they apply by including in food, tea, soups or smoke, rub the skin, or smear the affected part as the case may be. The plants frequently used by specialist healers are usually obtained from secluded places and administered after an elaborate diagnosis and complex mixing an intensive treatment and by the specialist himself.
Efforts Geared at Traditional Medicinal Plants
These are studies conducted on various aspects of traditional medicinal plants in Ethiopia. However, well focused studies targeted to both research and development are still missing. The documentation of traditional medicinal plants appears to be in a better stage with the recent publication of four volumes of flora of Ethiopia and extensive collection of plants throughout the country. However, these collections do not have sufficient ethno botanical information as the collections did not primarily focus at documenting medicinal plants. Over the years, attempts have been made to recover the species with medicinal value as could be seen in Mesfin Tadesse 1986, Gelahun Abate 1989, mesfin Tadesse and Ssebsebe Demissew 1992. The utilization aspect has also been studied by the department for traditional medicine while conservation is to be seen as part of forest and nature conservation in some zones. The GEF supported project on a dynamic farmer-based approach to the conservation of Ethiopia's plant genetic resources, which envisages establishment of botanic gardens in project sites, is being implemented by the Biodiversity institute. The recent report indicates that there are attempts to demarcate places for botanic gardens at two sites. Since Ethiopia is a big country with diverse agro ecologies, these efforts are far too shorter than the needs. The strategic role of the home garden has for long escaped sights of appropriate development/conservation schemes and has not been targeted for modern conservation production of traditional medicinal plants. A project, now at the stage of writing a proposal, is being initiated in the country and it appears to be multidisciplinary and keen on the role of home gardens.
Constraints and Gaps in Conservation and Use of Traditional Medicinal Plants
Many plants used in traditional medicine are harvested from natural stands and some of these are becoming more and more limited in distribution as a result of agricultural expansion and habitat shrinkage (e.g. Hagenia abyssinica) and overuse at least in some cases (e.g. Taverniera abyssinca, clausiena anisata). A major current concern, therefore, is to enhance not only conservation but also production of medicinal plants. The potential of home gardens in the conservation and use of medicinal plants is considered high and would need to be integrated with other options. While some medicinal plants are cultivated for other purposes and do not as such face conservation problems, those that used to be common weeds in gardens are being abandoned as a result of intensification of the home garden farming system. A major observation made during the study was that plants cultivated primarily for their medicinal value are very few and the traditional medical lore depends to a great extent on wild grown plants. It appeared that the role of home gardens for continuously domesticating new plants, the medical efficacy of which is acknowledged by the society, has not been encouraging being related to the knowledge system and the healing practice that evolved over generations. The other problem is connected with the pre eminent function of the home garden which is more of food and economy oriented in addition to the fact the at the space is mostly limited and cannot be expanded to incorporate many new plants. Modern agriculture failed to see the home garden as a production and conservation facility of the traditional agricultural system. The new movement in the country for crop on-farm in-situ conservation will ultimately lead to the recognition of the value of home gardening for conservation of the agro biodiversity including wild and weedy crop relatives.
Need for Improvement of the Traditional Medicinal Plants Sector
In order to improve the situation of medicinal plants in Ethiopia, a number of options come to mind. These can be seen under production, conservation, improvement, processing and exchange systems. The home gardens will be a good target of attention to positively respond to many of the needs of traditional health care system that exists in Ethiopia today. One very important strategy, therefore, will be to enhance the farming system of the home garden to enable more production and effective conservation of medicinal plants. However, for a comprehensive approach the medicinal plants industry would need to consider other options of cultivation and conservation outlined below as well as improvement of the delivery system to include market incentives.
Enhancement of Cultivation of Medicinal Plants in Home Gardens
In order to enhance the role of traditional medicinal plants in the community, the home gardens are central targets for in-situ conservation of existing species and ex-situ conservation of wild species through domestication and cultivation. Many home gardens in Ethiopia are not optimally used with respect to space and niching the growth forms. In some areas the space surrounding the house is not utilized while in others there are unused spaces. Even well developed home gardens can find some places for important medicinal plants if families are convinced about their uses in domestic health care and income generation. It is possible to fit many new medicinal plants into the home garden faming system. However, there may be space limitation in some of the already overburdened home gardens.
Farmers usually plant few plants on experimental basis closely observing them before production. This testing period allows seeing if the new plants are in some way detrimental to other garden crops. Since some wild plants are disease reservoirs, domestication of wild medicinal plants should be handled professionally with the assistance of farmers. Furthermore, it should be noted that some wild plants are adapted to marginal poor soils and fail to fit in the fertile home garden environment. Unworked plots within the home garden can be devoted for growing wild medicinal plants for gradual domestication. The introduction of new medicinal plants into the home garden must also pay particular attention to ethical issues concerning toxicity.
Enhancement of Traditional Medicinal Plants by other Means
The home garden is one major avenue for enhancement of conservation and use of medicinal plants. However, since medicinal plants are many in number and also very diverse in their botany and ecology, other conservation and production methods including those discussed below need to be motivated.
Establishment of Small - Scale Special Medicinal Plant Gardens
Some traditional healers have started establishing small compound gardens where they grow most of the medicinal plants they need for their work. Below ( Fig 3) is a sketch and description of one such garden seen in the compound of a nature clinic in Addis Ababa. This is kindly shown to us by the owner, who has already set a good example not only in the large number of plants he has managed to grow continuously but also in the style of cultivation he adopted. Most of the medicinal plants are grown in a plot wherein the pattern of planting is more or random and there is no weeding so that the plot appears like a natural stand wherein weedy medicinal plants get incorporated spontaneously and many of them regenerate naturally. In another plot in the same compound other species are planted with vegetables under intensive care. At the back of the house there are profusely growing medicinal plants including Achyranthes aspera, Ricinus communis, Tropaoleum sp. and Ipomea sp. which the healer uses in his formulations. The compound has many other species growing rather informally, thus sufficiently increasing the diversity of medicinal plant without having to depend on nature alone, but optimizing the new nature cure drive.
There are many traditional healers in Addis Ababa but most of them use plants mostly collected from nature. Only some of them are keen in cultivating some plants that are common components of traditional home gardens. The plants observed in the compound of one well-known healer were Ruta Chalepensis, Laggera sp., Ocimum lamifolium and Vernonia amygdalina. Use of medicinal plants from nature by professional healers cannot be sustainable particularly when the species is rare and its habitat is narrow. Women by contrast cannot grow more of the traditional home garden crops partly as spices and partly as medicines even in urban areas like Addis Ababa.
In one rural home garden 20 of the species grown for various purposes are known to have medicinal value. Together with the medicinal species of the fences and garden weeds the number available to families is considerable, but the use is limited by the healing system. Even in this village the preparations of the professional traditional healer are obtained from his own garden or elsewhere. When the healer has to prepare the medicine from the customers garden he makes sure that he goes alone in the garden and comes back with meshed up plant material such that no one would know what plant it came from.
Conservation of Traditional Medicinal Plants in Nature Reserves
Some traditional plants may have to conserved in - situ in their natural habitats due to difficulty for domestication and management or failure to produce the desired amount and quality of the active principles under cultivation (Franz 1993).
Large Scale medicinal Plant Farms
Depending on the level of development of the medicinal plant industry, large-scale private medicinal plant farms can be established to produce plant material for analysis. This will turn out to be a lucrative business since mostly vegetative material (leaves, etc.) are harvested, without having to wait for fruiting.
In - situ Conservation of the Biodiversity of medicinal Plants in Special Places
Medicinal plants can also be conserved by ensuring and encouraging their growth in special places, as they have been traditionally, within the cultivated landscape including in places of worship (churches, mosques, grave yards, etc.), sacred grooves, farm margins, river banks, roadsides, rocky outcrops in fields, trees in fields/villages, live fences of gardens and fields, etc., where native species thrive. It may also be possible to conserve tree and shrub species of medicinal plants by using them in afforestation and hillside plantation programmes of re - vegetating hillsides.
Conservation of Medicinal Plants by Conventional Ex-Situ Methods
Alongside the above methods of conservation and conventional ex-situ methods including gene banks, botanical gardens and field gene banks should be considered.
Domestication/Cultivation of Medicinal Plants in Home Gardens
Most medicinal Plants of Ethiopia and the world at large are wild. The development of the medicinal plants industry without endangering biological diversity can only come if the important wild medicinal plants are domesticated. This is what has been arrived at many international forums (Franz 1993). Three main advantages of this strategy are conservation, large-scale production and standardization of products through growth manipulations and genetic improvement. This will also preserve the indigenous knowledge on the conservation and use of medicinal plants. Though domestication of wild species is a tedious process, it has to be made. To overcome this problem, the traditional knowledge and practice could be useful and should be adopted through a partnership with local farmers and farming communities. Given the long tradition in Ethiopia of crop domestication and introduction, the domestication of selected wild medicinal plants will not be a problem to farmers as long as they are convinced about their uses. Efforts to domesticate wild growing medicinal plants in home gardens can adopt the following procedure (Franz 1993) in addition to practices of local farmers.
* Study of the natural habitat, botany/ethnobotany, ethnomedicine, soil, climate, growing, natural distribution and propagation (much information from indigenous knowledge) of important wild - grown medicinal plants
* Collection of wild grown plants, seeds and phytochemcal screening
* Plant propagation, vegetative/seed. Plantlet cultivation, in-vitro methods
* Genetic improvement, variability, selection, breeding, phytochemical investigation
* Cutivation treatments, growing site, fertilization, crop maintenance and cultivation
* Duration of cultivation, harvest/post-harvest handling, phytochemical control of produce
* Apply procedure for introduction of new crops blended with farmer methods
Economic evaluation and calculations
The cultivation of newly domesticated medicinal plants and introduced ones will be essential in order to increase the contribution of medicinal plants in the health care system of Ethiopia.
The Path Ahead
In Ethiopia, home gardens are important traditional innovations much concerned with the continuous provision of food and other basic necessities and home gardening is a ling standing practice. Most of the crops maintained on-farm are also indigenous, but the system has also been dynamic, introducing exotic plants found to be useful, suitable and well fitting into the culture and the ecology. However, their critical importance in food security and in-situ conservation of the agro biodiversity of traditional crops and associated wild and weedy relatives seem to have eluded the necessary emphasis by modern agricultural and community development interventions. The modern agricultural system has not been able to appreciate the totality of the traditional system and the crops as a viable system for promotion. The modern system works hard to produce few high yielding international crops based on marketed seeds, while traditional home gardening is based on diversifying the tax to have little of everything which spreads the risks and maximizes the nutritional diversity being concerned not only for people but also for animals. Until modern agricultural systems consider home gardens viable and become committed to develop appropriate enhancement strategies, other parties such as non-governmental organizations can engage in participatory programmes. They can study the system, learn from it and try to positively influence it without pushing for monoculture gardens, as has been the practice earlier on. In Welayita, it was observed that with growing urbanization home gardens are evolving to a near monoculture of few tree crops (Zemede Asfaw and Zerihun Woldu 1997), being influenced by promotion from the modrn agricultural sector which emphasized on the financial returns, disregarding the diversity of products, nutritional value and the primary home-use functions.
The conservation of traditional medicinal plants must be looked at in a holistic manner so that not only in-situ but also ex-situ options are motivated. Such an approach would automatically serve the objectives envisaged by Article 8(j) of the Convention on Biological Diversity (CBD 1994, BIOTHAI and GRAIN 1997). This article of the convention call for respect, maintenance and preservation of knowledge, innovations and practices of indigenous and local communities embodying traditional lifestyles relevant for the conservation and enable use of biological diversity and promote wider application with approval and involvement of the holders of such knowledge, innovations and practices and encourage equitable sharing of benefits arising from utilization of such knowledge, innovations and practices. The article draws attention to the protection of many rights (IUCN 1993, BIOTHAI and GRAIN1997), and instruments developed following the wishes of the Convention should submit to its basic doctrine. When it comes to application, it is not advisable to single out this paragraph since conservation should be seen like a package of in-situ and ex-situ which are given separately for the purpose of improving clarity for implementation. The article assumes that there will be honesty and harmony in regional and global collaborations to preserve and use biological diversity and indigenous innovations in the best interest of collaborating parties. The main issue is protection of biodiversity an associated knowledge systems from individualization of benefits by such things as intellectual property rights and patent laws that exclude those who generated and maintained the resources and the knowledge through generations.
RECOMMENDATIONS
The home gardens in Ethiopia have been important in production and conservation of such critical plant species as medicinal plants. They allow for integration of medicinal plants with other categories of plants offering multiple uses. A plant which has medicinal and other uses is most likely to be quickly accepted and cultivated in home gardens by farming communities as it allows them to get multiple advantages as has been the case traditionally. A food plant with medicinal property will attract even better attention of farming families because of the added fact that there will be less risks of toxicity (the part used as medicine may be toxic) when used as medicine. Conservation and production of medicinal plants primarily in home gardens must be given priority along with other conservation options and market incentives. It is therefore imperative that the following recommended steps be realized.
* Recognize home gardens as important places for conservation and production of important categories of plants such as medicinal plants and promote their intensification and enhancement,
* Study important wild growing medicinal plant with a vision for domestication in home gardens and subsequent cultivation through step by step strategy,
* Compile and build a compendium of information on each tax on of interest
* Start a two-way awareness creation scheme for development agents/NGOs and local people learning from each other,
* With the local people, identify wild-growing medicinal plants that can fit into the home garden agro-culture, considering botanical, social and ethical/factors,
* Classify the plants for short, medium and long-term domestication/cultivation in home gardens of the main agro ecological zones,
* learn from the people who have knowledge on uses of propagation methods,
* Activate conservation of medicinal plants in all possible ways in a holistic approach and for medicinal plants not recommended for cultivation in home gardens ensure implementation of one or more of the methods outlined,
* Identify families who will be willing to start experimental planting of selected species in their home gardens and initiate actual domestication and cultivation,
* For all medicinal plants in home gardens create market incentives so that the production level of families will rise,
* Develop technologies for crude extracts of medicines with keen visions for improvement to modern pharmaceutical formulations,
* Strengthen faithful regional and global cooperation to ensure conservation, development and equitable sharing of the benefits that accrue from traditional medicinal plants.
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