2. Some figures to start with ...

2.1. How many MAP are used world-wide?

The number of plant species which have at one time or another been used in some culture for medicinal purposes can only be estimated. An enumeration of the WHO from the late 1970s listed 21 000 medicinal species (Penso 1980). However, in China alone 4 941 of 26 092 native species are used as drugs in Chinese traditional medicine (Duke and Ayensu 1985), an astonishing 18.9 percent. If this proportion is calculated for other well-known medicinal floras and then applied to the global total of 422 000 flowering plant species (Bramwell 2002; Govaert 2001), it can be estimated that the number of plant species used for medicinal purposes is more than 50 000 (Table 1).

We recognize, however, that certain plant families have higher proportions of medicinal plants than others. Good examples are the Apocynaceae, Araliaceae, Apiaceae, Asclepiadaceae, Canellaceae, Guttiferae and Menispermaceae. In addition, these families are not distributed uniformly across the world. As a consequence, not only do some floras have higher proportions of medicinal plants than others, but also have certain plant families a higher proportion of threatened species than others (Table 9 in Appendix 1).

2.2. How many MAP species are traded?

It is difficult to assess how many MAP are commercially traded, either on a national or even an international level. The bulk of the plant material is exported from developing countries while major markets are in the developed countries. An analysis of UNCTAD trade figures for 1981-1998 reflects this almost universal feature of MAP trade (Table 2). Adding the volumes for the five European countries in this list (94 300 tonnes) marks the dominance of Europe as an import region. Germany ranks fourth and third as importer and exporter, expressing the country's major role as a turntable for medicinal plant raw materials world-wide.

Iqbal (1993) estimates that about "4 000 to 6 000 botanicals are of commercial importance", another source refers to 5-6 000 "botanicals entering the world market" (SCBD 2001). A thorough investigation of the German medicinal plant trade identified a total of 1 543 MAP being traded or offered on the German market (Lange and Schippmann 1997). An extension of this survey to Europe as a whole arrived at 2 000 species in trade for medicinal purposes (Lange 1998). Recognizing the role of Europe as a sink for MAP traded from all regions of the world, it is a qualified guess that the total number of MAP in international trade will be around 2 500 species world-wide.

2.3. How many MAP are threatened world-wide?

To satisfy the regional and international markets, the plant sources for expanding local, regional and international markets are harvested in increasing volumes and largely from wild populations (Kuipers 1997; Lange 1998). Supplies of wild plants in general are increasingly limited by deforestation from logging and conversion to plantations, pasture and agriculture (Ahmad 1998; Cunningham 1993).

In many cases, the impact through direct off-take goes hand-in-hand with decline owing to changes in land use. Species favoured by extensive agricultural management likeArnica montanain central Europe go into decline with changes in farming practices towards higher nutrient input on the meadows. This requires habitat management as the key factor in managing species populations (Ellenberger 1999).

One of the goals of the IUCN Medicinal Plant Specialist Group is to identify the species that have become threatened by non-sustainable harvest and other factors (see Appendix 4). The enormity of this task is illustrated by the following estimate: According to Walter and Gillett (1998), 34 000 species or 8 percent of the world's flora are threatened with extinction. If this is applied to our earlier estimate that 52 000 plant species are used medicinally, it leads us to estimate that 4 160 MAP species are threatened (Table 3).

2.4. How many MAP are under cultivation?

Many medicinal plants, especially the aromatic herbs, are grown in home gardens, some are cultivated as field crops, either in sole cropping or in intercropping systems and rarely as plantation crops (Paduaet al.1999).

In a survey carried out for the Rainforest Alliance, companies involved in trade and production of herbal remedies and other botanical products were asked what percentage of their material is from cultivated sources and what percentage from the wild. On average, companies reported that 60-90 percent of material was cultivated, with the remaining wild harvested. However, when asked about species numbers rather than volume of material, the figures are generally inverted (Laird and Pierce 2002). Lange and Schippmann (1997) state that of the 1 543 species traded in Germany, only 50-100 species (3-6 percent) are exclusively sourced from cultivation.

Of more than 400 plants species used for production of medicine by the Indian herbal industry, fewer than 20 species are currently under cultivation in different parts of the country (Uniyalet al.2000). In China, about 5 000 medicinal plants have been identified and about 1 000 are more commonly used, but only 100-250 species are cultivated (Xiao Pei-Gen 1991, He Shan-An and Ning Sheng 1997). In Hungary, a country with a long tradition of MAP cultivation, only 40 species are cultivated for commercial production (Bernáth 1999; Palevitch 1991). In Europe as a whole, only 130-140 MAP species are cultivated (Pank 1998; Verlet and Leclercq 1999).

Based on these figures, we assume that the number of MAP species currently in formal cultivation for commercial production does not exceed a few hundred world-wide. A global survey on the extent of MAP cultivation in terms of species, volumes and values would be highly desirable. On the other hand, however, we recognize that many more MAP species are cultivated on a small-scale in home gardens, either as home remedies or by herbalist or cultivation by local people can take place as enrichment planting.