The Araliaceae family is very old, and its representatives were already known among the first floral plants. This dates back to Early Cretaceous, that is to about 118 million years before present. Southeast Asia is considered the center of the species diversity and, possibly, the origin of Araliaceae. Having spread from there, the ancestors of modern species of Araliaceae spread over a vast area. In the Tertiary, they occurred in most of Eurasia and America, moving far to the north to extend even into the Arctic. The oldest traces of Araliaceae have been revealed in the Far East, in the south of Primorye (near Partizansk), and in the north, in the Kolyma River basin.

Under the impact of periodic glaciations, the specific composition and distribution of Aralia was substantially reduced, only slightly more than two dozen species having been preserved in the temperate zone.

In the territory of Russia, the greatest number of species of Araliaceae were preserved in the very south of the Russian Far East. A. L Takhtadjan, a well-known Russian botanist, assigned the region to the East Asian floristic range, which was not only a major center of development of higher plants, but a major refugium for Tertiary flora.

The contemporary state of various species of Russian Far Eastern Araliaceae is linked with both external factors and the ecological specifics of the plants themselves.

Eleutherococcus .senticosus and A. elata are successfully recruited in their natural habitats and are hardy. Their excellent ability at vegetative reproduction permits them to exist in relatively unfavorable conditions. However, mass uncontrolled collection of medicinal raw material from these plants may substantially reduce their natural stocks in Russian Far Eastern forests.

Eleutherococcus sessiliflorus in Khabarovsk Territory, at the northernmost part of its range, experiences significant man-made stress. Its populations has decrease on account of lumbering, fires, and collection of medicinal raw material. It is included in the list of rare plants of Khabarovsk Territory, and may be picked only under special licenses with no sale rights.

Intensive storing of O. elatus has led to considerable decrease in its resources, and today it is included in the list of rare plants of Khabarovsk Territory. Its resources in Primorye are exhausted also; the roots of O. elatus may be stored only in exceptional cases.

Extensive use of Kalopanax septemlobus caused its mass cutting, and it was entered in Russia's Red Book with subsequent ban of storing.

Fires and harvesting for medicinal purposes have also had a negative impact on A. continentalis resources, and the plant has also been included in Russia's Red Book.

Panax ginseng is now rated as "critically endangered." Its range has steadily become reduced, the basic cause being off ending storing, which has lately been done on a massive scale. Besides, humans also produce an indirect negative impact by cutting forests to cause overall drying of the climate, shallowing of rivers, and by fires.

Principal ways for preserving biodiversity of the Araliaceae of the Russian Far East:

I. Protection measures:

Rare and endangered plants are traditionally preserved by retaining their gene pool over areas excluded to various extent from human economic activity (in nature reserves, game refuges, national parks, etc.). The largest number of species per family occurs in Ussuri, Lazo, and "Kedrovaya Pad" nature reserves. Some Araliaceae are also largely present in such major introduction centers in Primorye as the Botanical Garden and "Gornotajezhnaya" Station, Far East Branch of the Russian Academy of Sciences.

The presence of a number of species of Araliaceae in nature reserves provides the hope that they are protected not only as species, but that their basic diversity is represented in protected areas. Unfortunately, this cannot be said of ginseng, since it occurs only in three nature reserves, all of which are located on the outskirts of the range.

To conserve ginseng, there is need for a very special and urgent system of measures. Current research and protection measures are focused on the following three trends:

1. Estimation and conservation of genetic variability of ginseng in natural habitats and protection of said habitats.

Researchers from the Institute of Biology and Soil Science (IBSS), Russian Academy of Sciences, have developed a concept for revealing and preserving the genetic polymorphism of ginseng (Muzarok et al., 1992; Zhuravlev, 1994). The concept is based on methods of molecular genetics (polymerase chain reaction for random amplified polymorphic DNA and methods of allozyme markers) and is aimed at studying the dynamics of wild-growing and cultured populations. Already today, approaches have been developed for identifying genotypes belonging to different populations and estimating their heterozygozsity. A detailed genetic assessment of the state of ginseng populations would be the basis for reintroducing and involving valuable genotypes in a relevant selection process.

2. Improving the system for protecting ginseng diversity through additional protection of most valuable (sub) populations, which may be present beyond protected areas.

This trend would assume the expansion of protected areas within the ginseng range, notably in its central and some peripheral parts, where according to preliminary studies, its most heterozygous representatives are concentrated.

3. Reintroduction of ginseng into its natural habitats.

This would require reliable genetic identification of stock material for reintroduction, something that is becoming quite realistic, given the investigations of researchers from the IBSS (see item 1, above). Besides, based on cell culture, IBSS researchers are able to preserve unique genetic material even from individual ginseng plants. To that end, sterile explantant containing a dormant bud is taken from wild plants. Special media permit to obtain there from a shoot with an inflorescence bearing unripe flower buds. From the latter, one can obtain embryogenic calli producing shoots and embryoids, artificial embryos of future plants. After special treatment, the growth and development of said embryoids is induced, and then also that of test-tube plants that are subsequently implanted. The thus obtained daughter plants largely correspond to the parent genotype, something that normally takes place in vegetative reproduction (Zhuravlev et al., 1990). Unique genotypes reproduced in this way and seed generations of plants collected in the defined habitats may be used for reintroduction of daughter plants in the same habitats.

II. Creating alternative sources of raw material:

Once the market is fully supplied with Russian Far Eastern Araliaceae material, one can expect that the man-made press on natural populations would reduce. A way to resolve the raw-material issue would be to develop effective know-how for reproducing plants on plantations and organizing the cell biomass production.

Growing ginseng on plantations is based on seed and vegetative reproduction. For most Far Eastern Araliaceae, know-how and seed stratification conditions have already been developed and seedling cultivation methods described. Vegetative reproduction has no such extensive application, but it would be needed when it would be necessary to replicate the mother plant properties.

Accumulation of cell biomass by tissue culture methods to obtain medicinal preparations was practiced on an industrial scale long ago, and ginseng was one of the first to be involved in this research. The first ginseng cell clone was obtained in 1960 at the K. A. Timirjazev lnstitute for Plant Physiology under the supervision of Corresponding Member of the Russian Academy of Sciences R. G. Butenko. In 1965, callus ginseng tissues maintained in continuous culture since 1960 were subjected to pharmacological analysis to show that, in its chemical composition, bioginseng is only slightly inferior to natural ginseng roots. By the early 1970s, a suspended ginseng cell culture was established to open prospects for industrially obtaining cell biomass. After a while, industrial production of ginseng cells began at the chemical work in Efremovo. By 1991, large amounts of ginseng cell biomass were also produced at chemical works in Omutninsk, the Vektor enterprise in Novosibirsk, at "Ginseng" enterprises in Pavlodar, and at the Biokhimmash enterprises, etc. Initially, bioginseng preparations were chiefly used in perfumery for making creams and shampoos. But already in 1989, the Russian Pharmacological Committee allowed the use of a bioginseng tincture as a tonic and stimulator of the central nerve system.

The manufacture of bioginseng encountered certain difficulties, when cultivated cells either grew poorly, or did not contain (or contained in small amounts) the most valuable dammaran glycosides (Uvarova et al., 1987; Elyakov et al., 1989). Besides, the amount of ginsenosides may vary not only in tinctures obtained at various chemical plants, but in various batches manufactured by the same plant as well (Reshetnyak and Nossov, 1993). There was need to find ways to increase the contents of biologically active substances in bioginseng.

New approaches to creating highly productive cell strains of ginseng by genetically transforming its cells were developed at the IBSS, to be followed by establishing so-called hairy root cultures. The latter emerge in the site where Agrobacterium rhizogenes microbes have infested the plant and can be isolated to produce a sterile culture. Such roots grow quicker than normal roots, albeit they are inferior in productivity to cell suspension cultures. They grow on simple cheap media. And yet, owing to their higher extent of differentiation (said roots contain some tissues typical of genuine roots), hairy roots may accumulate substances that are not synthesized in the non-differentiated callus mass and suspension cell cultures.

To obtain transgene cultures with an increased number of gene copies responsible for the key enzymes syntheses appears to be the most likely prospect in developing future research of ginseng genetic engineering.

III. Introduction:

Among the ways of preserving Araliaceae biodiversity, the essentially one is to introduce the plants in botanical gardens and arboretums both within and beyond their growth range. Owing to the fact that Araliaceae representatives possess highly-pronounced decorative and medicinal properties, they invariably attracted the attention of both Russian and foreign botanists. Already back in the 19th century, all Far Eastern Araliaceae were introduced into the culture, in Russia chiefly at the Petersburg Botanical Garden. Today, one can see them almost in any corner of Russia except for its northernmost regions.

List of illustrations:

Fig. 11.1. Protected areas within the geographic range of ginseng range in Russia: 1-4, actually existing nature reserves; l-VI, supposed habitats needing protection.

Fig. 11.2. Scheme for plant regeneration from dormant buds of unique specimens: 1, dormant explanted bud; 2, in vitro differentiation of shoot and inflorescence; 3, morphogenous callus induction from unripe flower buds; 4, forming of shoots and induction of embryoids; 5, implantation of test-tube shoots and small plants; 6, plants with signs of parent genotype for reintroduction.

Fig. 11.3. Hairy roots in transformed ginseng cultures.

Appendixes:

Formulas for remedies based on Araliaceae

Glossary

Key to species