During the last century the medicinal and aromatic plant sector has became a successful part of the Hungarian Agriculture. Some of the national products have been accepted as a special Hungarian ones ("Hungaricum"), evaluated on the world market, respectfully. By the estimates the cultivation area of medicinal and aromatic plants increased up to 37,000-42,000 hectares and considerable amount — about 10, 000-15, 000 tonnes of dry biomass — are produced by utilisation of Hungarian indigenous flora, year by year.

In the present work ecological requirements of 97 collected and 55 cultivated medicinal and aromatic plants are characterised. Based on the analysis of ^-Ts (temperature regime values) about 63 per cent of cultivated species came from Submediterranean and Mediterranean type of habitat, originally, while the majority of collected plants (61.8 per cent of them) prefer the deciduous forest conditions. The differences between collected and cultivated species are appreciable too, if the distributions of their characteristic water regime ('W' values) are compared. The majority of cultivated species require dry (moderate dry) and fresh (moderate fresh) habitats, while the amplitude of water requirement of collected species is much more wide-ranging.

The regional specialisation of Hungary according to production of medicinal and aromatic plants is known from the beginnings of the 20th century. As a result of spontaneous process seven well-defined production areas were developed. The relationship between regions, their climatic conditions and spectrum of species produced there are analysed.

The choice of varieties among medicinal plant species is relatively small, compared to other horticultural crops. In Hungary, only poppy (Papaver somniferum) and mustard (Sinapis alba) have several cultivars. Recognising the problem, in the recent years breeding activity has been intensified all over the world, in spite of financial, technical and legal difficulties. The article reports on the results of breeding at the Department of Medicinal and Aromatic Plants of the Szent István University, 11 varieties of which has been officially registered till 2000. Main goals of genetic improvement are: increasing of the production capacity of utilised plant organs, enhancement of active material accumulation capacity, improvement of sensory quality and technological properties. The most often applied methods are selection, and recently, cross breeding, the results of which can be measured on new materials of caraway (Carum carvi), hyssop (Hyssopus officinalis), marjoram (Majorana hortensis), poppy (Papaver somniferum), etc. Efficacy of breeding work is established by additional, regular research on the genetics, physiology, floral and reproductive biology, chemosyndromes of medicinal plant species.

Oxygen free radicals play an important role in the development of different disorders like inflammatory-immune injury, carcinogenesis, hepatic toxicity and artherosclerosis. The antioxydant role of a wide spectrum of natural products has been established. Flavonoids and other phenolic compounds (proanthocyanidins, rosmarinic acid, hydroxicinnamic derivatives, catechines, etc.) of plant origin have been reported as scavengers and inhibitors of lipid peroxidation.

We have studied the antioxidant activity as well as content and composition of natural phenolics in a series of medicinal plants with phytotherapeutical significance. Thus we determined the total phenol contents and studied the composition of flavonoids, polyphenols, phenolic acids of different vegetative and reproductive organs of medicinal plants: Anthriscus cerefolium (L.) Hoffm., Petroselinum crispum L., Cichorium intybus L., Helichrysum arenarium D.C.„cempervivum tectorum L., Taravacum officinale Web.

Characteristic constituents in the various crude drugs were determined by chromatographic (TLC, HPLC) and spectroscopic (UV, UV-VIS) methods. The non specific scavenger activities of the medicinal plant extracts were studied by the chemiluminometric technique. The changes of chemiluminescence intensity of the H,G,•0H-luminol system at increasing concentrations of the H₇0₂/ -OH were measured. Inhibitory effects of selected standardized fractions from plants were tested on ascorbic acid induced lipid peroxidation in rat liver and homogenates.

The best correlation were established with total phenolics in some medicinal plants (S. tectorum, T. officinale) while activities in other cases seem to be influenced by flavonoids (P. crispum, H. arenarium, A. cerefolium) and by hydroxicinnamic derivatives (C. intybus).

In this study we summarize the results of a five-years period concerning seed traits examinations on Iris pumila, Adonis vernalis, Primula veris and Alkanna tinctoria, with special attention to seed dimensions, seed mass and other traits concerning plant fitness, to their variability and the relationship among them. We found tight correlation between seed weight and seed dimensions in Adonis and Primula, at the same time no correlation exists among the same characters in Alkanna tinctoria. Consequently, the seed weight and seed dimensions can be used as synonyms in the form of „seed size" only after preliminary detection of correlations among them.

The variability of seed traits is higher in natural categories (individuals, morphs) than in seed mass categories as speculative groups. When we need homogeneous plant stand (e.g. for an introduction experiment) it is suggested to use seeds pre-selected in this way. For ex situ conservation, where the central goal is to maintain the genetic variability, seeds originated from different individuals are preferred.

As a part of the research project to establish natural sources of plant pigments, possibilities of introduction of Alkanna tinctoria (alkanet) into cultivation were studied.

As a result of the germination experiment, the relevance of 21 days' duration of germination procedure was proved. To get high germination rate alkanet fruits are proposed to pretreat by gibberellinic acid (GA3) in the concentration of 400 ppm, overnight before sowing. This method results approximately 50 % germination rate.

The morphological and production properties of alkanet roots are characterized during ontogenesis. Transplanted populations can be characterized by numerous, thick and heavy roots comparing to the spontaneous ones. Thus, seed sowing and transplantation proved to be an effective method for cultivation of the species.

According to our results it can be concluded that in cultivation the optimal harvesting time of roots is at the end of the second vegetation cycle, when the dry root mass of the individuals is about 10-20 g with 3,0-3,5 % accumulation level of active substances.

Considerable seasonal variability have been found influencing not only the root masses, but also the accumulation levels of alkannin derivatives. In a more humid vegetation cycle the root size and mass as well as the content of active substances are much higher.

In the temperate zone live about 150 species of the Nepeta genus. Our investigations covered the examinations of the volatile oil containing species of the genus endemic in Hungary, Nepeta cataria and Nepeta parviflora. Latter is a relict of the ancient steppe-flora and endemic in Hungary as well. Phytochemical examination of the volatile oil containing plant material has also been carried out. Catnip growing in the Botanical Garden of PTE Department of Botany contained 0,67% volatile oil in May and 0,14% in November. Chemical character of the volatile oils were measured by gas chromatography/mass spectrometry and citronellol, citral-A, citral-B and geraniol components were identified. The composition of the oil of November samples shifted towards citronellol (65%). In both samples insecticide and repellent activity bearing compounds (+)-cis-p-menthane-3,8-diol, and (—)-trans-p-menthane-3,8-diol in 2-2.5 and 4-4.5% amount have been found. The catnip sample deriving from Germany contained a small amount of anetol, citronellol, neral, geraniol and geranial (6-13%), and possibly two isomers of nepetalactone in 23-31%.

The Nepeta parviflora endemic in the Nagyvolgy valley near Nagykaracsony consisted of the same compounds in the investigated years (1998-2000). Its limonene, methyl chavicol, b-cariophyllene, b-selinene, b-cubebene, davanone, germacrene-D constituents have been identified. In the year 2000 different GC % of these compounds were detected in the different organs of the plants.

The closely related species Nepeta cataria var. citriodora contained 83% citral, and the N. glechoma (= Glechoma hederacea) contained 41% a-cubebene, 20% patchoulenol, 7,7% spathulenol respectively. These compounds were identified by gas chromatography and gas chromatography / mass spectrometry.

In the present work we have examined the changes of germination ability of some medicinal plant species belonging to the Solanaceae family (Datura stramonium L., Datura innoxia Mill. and Hyoscyamus niger L.) during 5-6 years' storage period. According to our results, all the three species showed an after-ripening behavior. Potassium nitrate and gibberellic acid increased significantly the rate of germination in the case of Datura species. During the storage period tested (1995-2001), the species maintained their germination ability which is favourably but not significantly influenced by the cooled gene bank conditions. The degree of ripeness affected considerably the proportion of germinated seeds at all the three species. As a consequence of our results we emphasise that propagation with completely ripe seeds is proposed, however, half-ripe seeds developped in an unadvantageous vegetation period can be also utilized in the practice. The effect of vegetation year on stramony seeds manifested in the length of after-ripening period, while in the case of henbane the germination ability was also influenced.

In this study the changes of the characteristics of Satureja hortensis herb were investigated during flowering period, in case of savories of 4 different origins. The change of drying ratio, leaf/stem ratio, essential oil content, the ratio of several essential oil components (carvacrol, y-terpinene, p-cymol, a-pinene, p-pinene and fi-caryophyllene) were studied from bud formation till seed ripening.

Angel's trumpet (Danira = Brugmansia arhorea) is a common, popular ornamental plant in Hungary. On the basis of thin layer chromatographic and densitometric alkaloid studies of leaf and flower samples collected from several places in Somogy and Baranya counties it can be stated that in samples of cultivars with different flower colour, taken approximately at the same time, the atropine and scopolamine content varies: there are samples free of alkaloids, but most of them are rich in alkaloids. Although the means do not reflect the extremes, they are suitable for determining the alkaloid accumulating capacity of flowers. Generally the amount of atropine and scopolamine is significant both in the leaf and the flower. It is conspicuous that the flower can be characterised by an extremely high scopolamine content (mean in mg/g dry matter of leaf: atropine 0.34, scopolamine 0.31; of flower: atropine 0.26, scopolamine 0.85). Thus it can be stated that the leaf, and especially the flower of angel's trumpet is a potential hallucinogen, just like in the case of Datura stramonium.

The investigations of the growth and alkaloid production of cell suspension-, callus-, organized- and hairy root cultures from Lobelia inflata L. proved that these cultures are able to synthesize the characteristic piperidine alkaloids of the intact plant. Alkaloid precursor amino acids (Phe, Lys) and plant growth regulators affect not only the growth and differentiation of tissue cultures but also their secondary metabolism. The synthetic regulator Sz/I I combined with Phe increased the total alkaloid content considerably in callus- and organized cultures; regulator Sz/28 especially increased the lobeline content (in organized cultures in response to Lys, in callus tissues as a result of Phe application). With the aim of optimizing growth and alkaloid production of the genetically transformed hairy root cultures of Lobelia inflata L. we studied the effect of some growth regulators (NAA, IAA, kinetin) and precursor amino acids (Lys, Phe). The kinetin had inhibiting effect on the growth and lobeline production of the hairy roots. The IAA and NAA increased the biomass formation and lobeline production. The highest lobeline level was detected in tissues cultivated on hormone-free medium containing Phe.

Marjoram is one of the most important spices in Hungary, which is utilized both in phytotherapy as well as in alimentary industry. Organoleptic quality of the drugs of two Hungarian varieties of Majorana hortensis /'Francia' and 'Magyar'/ were investigated by two different methods of sensory analysis. The chemical composition of the material was checked by GC analysis of the distilled essential oil. Although their main compounds and proportions showed similar patterns, both the human and instrumental sensory tests based on the complex odour and aroma of the drug, proved a significant differentiation of the two varieties.

On the basis of our results, sensory evaluation may be a useful tool in the practice in determination of complex aromatic values of marjoram, as a spice. At the same time it seems to be a suitable method in promotion of breeding efforts.

Authors dealt more than ten years with the analysis of supercritical extracts. For extraction (SFE) carbon dioxide was used as supercritical solvent. Fractionation of extracts was carried out by releasing the separations pressure at two stages. The extracts were collected as separate samples successively in time.

The traditional extractions were carried out with steam distillation or by using n-hexane and ethanol in Soxhlet apparatus. For the analysis of volatile compounds GC, GC-MS; of non volatile compounds TLC-densitometry and spectroscopic methods were used.

The following general characteristics were established comparing the composition of steam distillated oils with that of volatile SFE fractions. The SFE fractions were richer in monoterpene-esters and poorer in alcohols than the essential oils prepared by traditional way (clary sage, lavandel). Regarding the distributi,n of the monoterpene and sesquiterpene compounds, the SFE fractions contained sesquiterpene hydrocarbon in higher percentage than the distillated oils (e.g. 13-caryophyllene in Salvia fruticosa, (3-car_yoph_yllene, y­muurolene, y-cadinene in Ochnum basilicum). Further the proportion of sesquiterpenes increased in SFE fractions collected successively in time.Significant difference was remarkable in respect of the optical rotationability of lovage oil and SFE fraction which was probably caused by the different ratio between the two ligustilid enantiomers. It was verified in some cases that a part of mono- and sesquiterpenes were present originally in a bounded form (glycosides) in plants. Therefore they appeared in essential oil fractions only after previous acidic treatment (Thymus, Origanum species). During the supercritical extraction the azulenogene sesquiterpene lactones did not transform to azulenes (in chamomile, yarrow), but the non volatile SFE fractions of some Asteraceae plant contained sesquiterpene--lacton of unchanged structure in high quantity (e.g. cnicin in blessed thistle, parthenolide in feverfew). Authors obtained also SFE fractions which were rich in triterpenoids and phytosterols (marigold, common dandelion).

The effectiveness of drug plant and of essential oil of oregano (Origanum vulgare L. ssp. hirtum Ietswaart) against the adults and egg hatching of bean weevil (Acanthoscelides obtectus Say) was studied in laboratory trials in order to screen for a new potential insecticide in the control of this granary pest of beans. The adult mortality as well as oviposition and hatching capabilities were evaluated after 6 days of treatment of beans cv. `Berggold' (55 g) in Petri dishes by powdered drug (0.33 g, 0.66 g, 1.0 g and 2.0 g) and by equivalent amounts of essential oil (5 ill, 10 15 ill and 30 ill). Oregano essential oil showed both fumigant and contact toxicities to bean weevil, the later being more potent. When considering fumigant toxicity, insecticidal effect (mortality rate 82.5%) was observed 6 days after application of high concentrations of oregano essential oil (150 Al per 55 g of beans). When considering contact toxicity, both oregano drug plant and essential oil at all tested concentrations significantly increased the bean weevils' mortality rates with comparison to the controls. Also, egg laying and hatching were inhibited after treatment of bean weevil with powdered drug plant or with essential oil at all tested concentrations. Insecticidal effect of drug plants issuing from two different stocks depended on their essential oil contents. Essential oils (5 pi, 15 pi and 30 IA per 55 g of beans) induced 100% mortality of bean weevil population when applied directly to the surface of beans (55 g) in Petri dishes. The content of essential oil in oregano and oregano-based preparations for insecticidal use is proposed as a parameter for quality control purposes.