From nutrients to competition processes: Habitat specific threats to Arnica montana L. populations in Hesse, Germany.

Populations of Arnica montana, a characteristic species of nutrient poor grasslands in Central Europe, have been deteriorating over the last decades, especially in lowland regions. Population size has been declining and signs of sexual reproduction are scarce. To start a long-term regeneration program, we investigated the major habitat specific drivers for the decline in Hesse, Germany. Firstly, we conducted a field study to analyze habitat characteristics of 32 Hessian lowland sites, comparing those on which this species has become extinct during the last 15 years with sites of small and declining, as well as large, stable populations. We compared habitat traits focusing on soil parameters, nutrients, and vegetation characteristics. Secondly, we set up a greenhouse experiment to study the response of A. montana seedlings to competition and nutrient input to assess the effects of competition pressure and fertilization. The results show lower carbon-to-nitrogen ratios and higher Ellenberg nitrogen indicator values on sites with extinct populations compared to existing populations. Both pH and Ellenberg soil reaction indicator values were higher on sites with extinct populations. In the greenhouse, the combination of nitrogen addition and competition resulted in lower seedling numbers. While rosette size was not dependent on fertilization, growth was strongly enhanced in the plots lacking vegetation. Both studies suggest that soil nutrient enrichment followed by competition pressure diminishes the number of safe sites for A. montana seedling recruitment and establishment and negatively impacts the growth of existing rosettes, thus leading to the continuous decline of populations. There is an urgent need for actions to reduce unintentional nitrogen deposition in the remaining nutrient poor areas as well as to modify land use to withdraw nutrients from enriched soils in order to preserve the remaining A. montana populations and to create bare ground for the safekeeping and enhancement of self-sustainable populations.

Chemical Composition of Essential Oil from Flower Heads of Arnica Chamissonis Less. under a Nitrogen Impact.

Chamisso arnica (Arnica chamissonis Less.) is a valuable plant species used in the pharmaceutical industry due to the content of many pharmacologically active substances and the similarity of its chemical composition to that of Arnica montana-a medicinal plant commonly used in pharmacy and cosmetics. The similarity of the two plant species implies that chamisso arnica can be a pharmaceutical substitute for the mountain arnica, i.e., an endangered and endemic plant species in Europe. Chamisso arnica extracts exhibit anti-inflammatory and antiradical activity and possesses high antioxidant properties that might be helpful in preventing or delaying the progress of free radical dependent diseases. The attributes of A. chamissonis are mainly related to the content and chemical composition of essential oil. Therefore, the objective of this study was to characterize the chemical composition of essential oil derived from A. chamissonis flower heads under a nitrogen impact. The experiment was performed on experimental fields in mid-eastern Poland on two soil types (sandy and loamy soils). The nitrogen fertilizer was applied as ammonium sulfate (control, 30, 60, 90, and 120 kg N ha-1). Collection of flower heads was carried out in the full flowering phase, which was characterized by the highest content of essential oil. The chemical composition of essential oil was examined using GC-MS. Among the 75 ingredients of the volatile oil of chamisso arnica flower heads, alpha-pinene, cumene, p-cymene, germacrene D, spathulenol, decanal, caryophyllene oxide, beta-pinene, and benzene acetaldehyde were present at relatively high levels. Both the nitrogen application and the soil type had an effect on the oil concentration and the yield of the main constituents (alpha-pinene and germacrene D) with pharmacological value. Different levels of nitrogen application could be considered as a relevant way to modify the chemical composition and to increase the essential oil production.

Propagation and introduction of Arnica montana L. into cultivation: a step to reduce the pressure on endangered and high-valued medicinal plant species.

Arnica montana (L.) is an endangered and endemic medicinal plant species in Europe. The pressure on natural sources of this plant is alleviated by a suitable use of arnica resources in the European region and introduction into cultivation. The objective of this study was to describe the impact of different ways of plant propagation and introduction on the growth and reproduction mode of this species. During the six consecutive years of the field experiment, the vegetative and reproductive traits were monitored, and survival time was assessed. The particular ways of arnica plant propagation and introduction determined all the intrinsic species traits and plant survival. The values of the characteristics studied indicated good acclimatization of the arnica ecotype to the climatic conditions of eastern Poland. Practical implications from the data presented here include the possibility of using the presented modes of arnica propagation and introduction in the short- and long-term perspective of arnica cultivation, which can give a possibility of better adjustment of raw material production.

Efeito de dinamizações de Arnica montana L. no metabolismo de chambá (Justicia pectoralis Jacq. ) / Effect of dynamizations of Arnica montana in metabolism of chambá (Justicia pectoralis Jacq. )

Este estudo objetivou avaliar a resposta do crescimento e do metabolismo secundário de Justicia pectoralis, expresso em produção de cumarina, a crescentes dinamizações de A. montana. O experimento foi conduzido na Universidade Federal de Viçosa. O delineamento estatístico foi inteiramente casualizado, com seis repetições e cinco tratamentos, totalizando 30 parcelas experimentais, sendo cada parcela constituída de uma planta por vaso. Os tratamentos foram as dinamizações 3CH, 30CH, 60CH, 100CH e 200CH do preparado homeopático A. montana. Os tratamentos foram aplicados às plantas via pulverização, em intervalos semanais, iniciando logo após o plantio. Após quatro meses do plantio as plantas foram colhidas. As características de crescimento avaliadas foram matérias fresca e seca de folhas e caules, matérias fresca e seca de inflorescências e matérias fresca e seca total. No estudo fitoquímico foi avaliada a produção da cumarina (1-2 benzopirona). Não houve resposta nas variáveis de crescimento aos tratamentos. As dinamizações de A. montana causaram alterações no metabolismo secundário das plantas. Os conteúdos de cumarina das plantas com A. montana 3CH e 30CH foram próximos e mais baixos, aumentando progressivamente a partir de 60CH, chegando ao máximo em 100CH, seguido de redução em 200CH. A preparação homeopática A. montana causa alterações no metabolismo secundário de chambá, sendo as repostas dependentes da dinamização.

Were evaluated the responses to dynamizations of Arnica montana in the growth and in the secondary metabolism of Justicia pectoralis expressed as coumarin production. The studies were carried out at the Universidade Federal de Viçosa. The statistical design was completely randomized, with six replicates and five treatments, 30 experimental plots, one plant per pot. The treatments were dynamizations 3CH, 30CH, 60CH, 100CH and 200CH homeopathic preparation of A. montana. The application the treatments begun are planting seedlings, the aerial part being sprayed, at weekly intervals. After four months of planting, the plants were harvested. The evaluated growth characteristics were: fresh and dry matter of leaves and stems, fresh and dry matter of inflorecenses, and fresh and dry matter total. In the phytochemistry study, the production of the coumarin 1,2-benzopyrone was evaluated. Were no responses of growth characteristics. The dynamizations of A. montana caused changes in secondary metabolism of plants. The coumarin production with A. montana plants 3CH and 30CH were lower, increasing progressively from 60CH, and coming to increased in 100CH, followed by a large reduction in the 200CH. The homeopathic preparation A. montana cause change in secondary metabolism of chambá, and the responses depend on dynamizations.

Optimization of culture conditions of Arnica montana L.: effects of mycorrhizal fungi and competing plants.

Arnica montana is a rare plant that needs special protection because of its intensive harvesting for medicinal purposes. The present work was aimed at finding optimal culture conditions for Arnica plants in order to enable their successful reintroduction into their natural stands. Plants were cultivated under controlled greenhouse conditions on substrata with different nitrogen (N) concentration. As Arnica is always colonized by arbuscular mycorrhizal fungi (AMF) in nature, a fact that has been overlooked in other similar projects, we, here, applied and tested different inocula. We found that they differed in their effectiveness, both in establishing symbiosis, assessed by the colonization parameters, and in improving the performance of Arnica, evaluated by the photosynthetic parameters derived from the fluorescence transients (JIP-test), with the inocula containing G. intraradices or composed of several Glomus strains being the most effective. The comparison was possible only on substrata with medium N, since high N did not permit the formation of mycorrhiza, while at low N, few nonmycorrhizal plants survived until the measurements and mycorrhizal plants, which were well growing, exhibited a high heterogeneity. Analysis of secondary metabolites showed clearly that mycorrhization was associated with increased concentrations of phenolic acids in roots. For some of the inocula used, a tendency for increase of the level of phenolic acids in shoots and of sesquiterpene lactones, both in roots and in shoots, was also observed. We also studied the interactions between A. montana and Dactylis glomerata, known to compete with Arnica under field conditions. When specimens from both species were cultured together, there was no effect on D. glomerata, but Arnica could retain a photosynthetic performance that permitted survivability only in the presence of AMF; without AMF, the photosynthetic performance was lower, and the plants were eventually totally outcompeted.