Centaurea Scabiosa Research Articles

ПРИМЕНЕНИЕ МИКРОСПЕКТРОФЛУОРИМЕТРА / МИКРОСПЕКТРОФОТОМЕТРА ДЛЯ ИССЛЕДОВАНИЯ ПОВЕРХНОСТИ РАСТИТЕЛЬНЫХ КЛЕТОК

The fluorescence and absorbance spectra of intact plant leaf cells from juniper Juniperus excelsa, Jerusalem-sage Phlomis tuberosa, butterbur Petasites spurius, centaury Centaurea scabiosa and wild chervil Anthriscus sylvestris have been obtained using the microspectrofluorimeter/ microspectrophotometer MSF-15 (LOMO, St. Petersburg). The obtained spectra of autofluorescence and absorbance made it possible to test the composition of compounds outside the cell wall. This tool is able to detect the presence of secretions on the surface of intact cells, including secondary metabolites with the fluorescence maxima in the region of 530-550 nm, characteristic of phenolic compounds. In the absorbance spectra of leaves, maxima were found in the region of 580-620 nm, which is peculiar to blue pigments azulenes. The presence of azulenes on the surface of cells has been confirmed by short-term extraction of these pigments with ethanol or acetone. Similar methodical approach has been recommended for rapid analysis of intact surfaces of plant cells.

Germination performance of alien and native species could shape community assembly of temperate grasslands under different temperature scenarios

Rising temperatures due to climate change are expected to interplay with biological invasions, and may enhance the spread and growth of some alien species upon arrival in new areas. To successfully invade, a plant species needs to overcome multiple biological barriers. Among the crucial life stages, seed germination greatly contributes to the final species assembly of a plant community. Several studies have suggested that alien plant success is related to their high seed germination and longevity in the soil. Hence, our aim is to test if the germination potential of alien seeds present in the seed bank will be further enhanced by future warming in temperate dry grasslands, an ecosystem that is among those most prone to biological invasions. We designed a laboratory germination experiment at two temperatures (20 and 28 °C), to simulate an early or late heat wave in the growing season, using seeds from nine common grassland Asteraceae species, including native, archaeophyte and neophyte species. The test was performed on both single and mixed pools of these categories of species, using a full-factorial orthogonal design. The warmer germination temperature promoted neophyte success by increasing germination probability and germination speed, while negatively impacting these parameters in seeds of native species. The co-occurrence of native and archaeophyte seeds at the lower temperature limited the invasiveness of neophytes. These results provide important information on future management actions aimed at containing alien plant invasions, by improving our knowledge on the possible seed-bank response and interaction mechanisms of common species occurring in disturbed natural areas or restored sites.Graphical abstractSummary of the experimental results. The colour of the flowers represent the status, divided as native (blue), neophyte (red) and archaeophyte (green). Each flower symbol represents the species pool for each plant category (i.e. NA = Buphthalmum salicifolium, Carlina vulgaris, Centaurea scabiosa; NE = Artemisia annua, Symphyotrichum novi-belgii, Senecio inaequidens; AR = Centaurea cyanus, Cichorium intybus, Tripleurospermum inodorum). The number of flowers represent the germination percentage of the various category assembly. In the columns are divided the various combination. From up to bottom the trend of germination percentage at 20 and 28 °C are shown.

RESOURCE MELLIFEROUS-POLLENIFEROUS ROLE OF INVASIVE PLANTS IN RUSSIA

The resource melliferous-polleniferous potential of Russian invasive plant species was studied on the basis of the results of melissopalynological (pollen) analysis. The study of the pollen composition of 2121 honey samples from 70 Russian regions made it possible to diagnose the pollen of 26 invasive plants in their composition, 13 of which were resource plants. In the European part of Russia, important melliferous plants were Robinia pseudoacacia L., Gleditsia triacanthos L., Amorpha fruticosa L., Solidago canadensis L., and Ailanthus altissima (Miller) Swingle. Monofloral honey types from these invasive species were obtained mainly in the southern regions. In Siberia, Centaurea scabiosa L., C. jacea L., Echium vulgare L., and Co nium maculatum L. were of resource importance. Monofloral greater and brown knapweed, viper`s bugloss and wild hemlock honey types were found mainly in the regions of Western Siberia. In the Far East, sources of monofloral honey were Nonea rossica Steven and Amoria hybrida (L.) C. Presl. The species Lupinus polyphyllus Lindll. and species of the genus Ambrosia were classified as important Russian polleniferous plants.

Nontarget catches of traps with chemical lures may refer to the flower‐visitation, probable pollination, and feeding of bush crickets (Ensifera: Tettigoniidae)

AbstractThe diurnal bees, lepidopterans, and other pollinators are among the most studied flower‐visiting insect taxa. They mostly play distinct functions in temperate grasslands and ecotones of grassland‐forest mosaics (such as in forest steppes). Although orthopterans are widely distributed in these habitats, however, their flower visitation is nearly unknown, especially in the temperate zone. During the development of traps with chemical lures to catch Lepidoptera pests, large numbers of Orthoptera were caught that provide a chance for studying the flower visitation and odor and indirectly the host plant preference of seven temperate zone Tettigoniidae species. Data on the attractivity of isoamyl alcohol‐based semisynthetic lures for Meconema thalassinum and efficiency of phenylacetaldehyde‐based lures on Leptophyes albovittata and Phaneroptera falcata were reported for the first time. Additionally, analysis of nature photos collected from internet sources, as part of a passive citizen science also supports the revealed preference of these species. Based on photos, the studied orthopterans mainly visit Asteraceae species including the most preferred Tanacetum vulgare, Pulicaria dysenterica, Achillea millefolium, Solidago canadensis, and Centaurea scabiosa. Based on catches of volatile traps, the first data were recorded on the attractivity of phenylacetaldehyde‐ and isoamyl alcohol‐based lures on three temperate zone Orthoptera species. Results of a passive citizen science study strengthen these results that may increase the knowledge on the host plant and habitat preference of Orthoptera species.

Anti-glutamatergic Effects of Three Lignan Compounds: Arctigenin, Matairesinol and Trachelogenin - An ex vivo Study on Rat Brain Slices.

Arctigenin is a bioactive dibenzylbutyrolactone-type lignan exhibiting various pharmacological activities. The neuroprotective effects of arctigenin were demonstrated to be mediated via inhibition of AMPA and KA type glutamate receptors in the somatosensory cortex of the rat brain. The aim of this study was to compare the effects of arctigenin with matairesinol and trachelogenin on synaptic activity in ex vivo rat brain slices. Arctigenin, matairesinol and trachelogenin were isolated from Arctium lappa, Centaurea scabiosa and Cirsium arvense, respectively, and applied on brain slices via perfusion medium at the concentration range of 0.5 - 40 µM. The effects of the lignans were examined in the CA1 hippocampus and the somatosensory cortex by recording electrically evoked field potentials. Arctigenin and trachelogenin caused a significant dose-dependent decrease in the amplitude of hippocampal population spikes (POPS) and the slope of excitatory postsynaptic potentials (EPSPs), whereas matairesinol (1 µM and 10 µM) decreased EPSP slope but had no effect on POPS amplitude. Trachelogenin effect (0.5 µM, 10 µM, 20 µM) was comparable to arctigenin (1 µM, 20 µM, 40 µM) (p > 0.05). In the neocortex, arctigenin (10 µM, 20 µM) and trachelogenin (10 µM) significantly decreased the amplitude of evoked potential early component, while matairesinol (1 µM and 10 µM) had no significant effect (p > 0.05). The results suggest that trachelogenin and arctigenin act via inhibition of AMPA and KA receptors in the brain and trachelogenin has a higher potency than arctigenin. Thus, trachelogenin and arctigenin could serve as lead compounds in the development of neuroprotective drugs.

Volatile Oil Chemical Composition of Wild, Edible Centaurea scabiosa L. and Its Cytotoxic Activity.

Centaurea species are well known as a source of phytopharmaceuticals having both beneficial and harmful influences on human health. Centaurea scabiosa L. is a wild edible plant used in Mediterranean cuisine in the Dalmatian region of Croatia. We have assessed the volatile oil's chemical composition using GC/MS chromatography and its cytotoxic activity on human fibroblasts using the MTT test. Data on chromosome number, obtained by classical karyological methods, and genome size, assessed by flow cytometry, of the same plant material of C. scabiosa, were also given. The major chemical compounds found in C. scabiosa volatile oil were heptacosane, caryophyllene oxide, alloaromadendrene epoxide, α-cyperone, and α-bisabolol. This volatile oil showed no cytotoxicity on human fibroblasts in a dose range of 0.01-1 g/L. The chromosome number of a C. scabiosa sample from Croatia showed 2n = 20 + 2B chromosomes. The total genome DNA amount of 2C = 3.3 ± 0.01 pg or 1 Cx = 1628 Mbp presents the first report on the genome size of this species from Croatia. The presented results support the idea of using this plant in the human diet. To our knowledge, this is the first report on edible C. scabiosa species in general and in particular from Croatia.

Flora of the former Kolokolnikov estate (Tyumen)

The article presents for the first time data on the species diversity of vascular plants growing on the territory of the former estate of the Kolokolnikovs, which has a history of formation for a century and a half and is today a place of rest for the citizens of Tyumen. In 2021, most of the study area was classified as a natural monument of regional significance «Lesopark (Parkland) Zatyumensky». For the spring-summer period 2021, 182 species of vascular plants belonging to 136 genera, 56 families were identified. Among the leading families: Asteraceae (22 species), Rosaceae (21), Poaceae (19), Fabaceae (14), Brassicaceae (9), Salicaceae (8), Caryophyllaceae (7), Apiaceae (6), Ranunculaceae (5), which accounted for 61 %. The arboreal layer is dominated by Betula pendula and Tilia cordata, and the grass-shrub layer is dominated by Aegopodium podagraria, Centaurea scabiosa, Geranium sibiricum, Glechoma hederacea, and Poa pratensis. On the territory there are species listed in the Red Book of the Tyumen region: Tilia cordata and Cerasus fruticosa (Prunus fruticosa). In a comparative analysis with herbarium funds, 33 plant species were not identified in the modern flora of the study area. According to the biomorphological analysis according to the system of life forms of K. Raunkier, most plants belong to hemicryptophytes (40.7 %), I. G. Serebryakova - long-rhizomatous polycarpics (21.5 %), O. V. Smirnova et al. - mono-centric type (52.2 %).

THE FIRST EXPERIENCE IN THE DEVELOPMENT OF THE RICHES OF THE VASYUGAN SWAMP

Introduction to Siberia of bees of different breeds such as Italian Apis mellifera ligustica Spin., Apis mellifera carnica Pollm., Kuban (yellow Caucasian) Apis mellifera remipes Gerst., Far Eastern Apis mellifera acervorum, grey mountain Caucasian Apis mellifera caucasica Gorb. led to the fact that crossbreeds of an unknown generation predominate in the Novosibirsk region. These bees are rich in swarms, do not winter well, and the egg-laying of the queens is low. Currently, the importation of packet bees has stopped due to sharp increases in fuel prices (fuels and lubricants) and air and rail transport. But the importation of fetal queen bees is still ongoing. The authors studied the method of reproduction of bee colonies to preserve the beekeeping industry in Western Siberia. In one of the promising regions of Western Siberia, in the Vasyugan swamps, nectariferous plants grow for breeding bees. In that place, plants grow such as Rubus idaeus L. (common raspberry), Angelica sylvestris L. (wood angelica), Archangelica decurrens L. (Siberian angelica), Ribus nigrum L. (black currant), Sonchus arvensis L. (field sow thistle), Melilotus officinalis L. (yellow sweet clover), Melilotus albus Medik. (White sweet clover), Centaurea scabiosa L. (rough cornflower), Salix L. (willow), Taraxacum Wigg. (dandelion), Dracocephalum nutans L. (Siberian snakehead), Glechoma bederaceae L. (ivy-shaped budra), Prunella vulgaris L. (common blackhead). These plants are an excellent forage base for beekeeping. For two years of research, the authors found that the collection of honey per bee colony was in the group where the bees were propagated by natural swarming, 51.8 ± 5.1 kg, individual layering - 49.9 ± 4.3, prefabricated layering - 55, 6±3.1 kg. The strength of the families that went into the winter was 8.47±0.30; 8.77±0.20 and 9.06±0.40 bee space, respectively. Reproduction of bee colonies for two years showed that it is possible to increase the number of bee colonies from 4 to 16 (403%) by natural swarming, by individual layers - up to 19 (572%), and teams - up to 17 (422%).

A review of the subtribe Centaureinae (Asteraceae, Cardueae) in Lithuania with information on new alien species

The study’s objective was to overview all Centaureinae species recorded in Lithuania, evaluate the distribution and population state of the newly discovered four alien species and provide information on the residence status, distribution and habitats occupied by all species of the subtribe. The subtribe Centaureinae in Lithuania is now represented by five genera: Centaurea, Leuzea, Psephellus, Serratula and Zoegea. The largest genus in the flora of the country is Centaurea, which includes four native and six alien species. The genus Serratula is represented by one native species, while the genera Leuzea, Psephellus and Zoegea each have one alien species. Tree alien species (an archaeophyte, Centaurea cyanus, and neophytes Centaurea montana and Psephellus dealbatus) are naturalised aliens, whereas Centaurea cheiranthifolia, Centaurea diffusa, Centaurea iberica, Centaurea macrocephala, Leuzea repens and Zoegea crinita are casual aliens. Five species of the subtribe Centaureinae (Centaurea jacea, Centaurea phrygia, Centaurea scabiosa, Centaurea stoebe and Serratula tinctoria) are native to Lithuania. Maps of the distribution of newly discovered alien species in Lithuania are presented.

Substances for biological protection, regulation of growth and development of agricultural crops based on secondary plant metabolites

Plants are a promising source of a wide range of biologically active substances as biopesticides and growth stimulants in organic agriculture. Screening of the antimicrobial activity of ethanol extracts of air-dry aboveground biomass of 22 plant species of the family Asteraceae, typical representatives of the flora of the Republic of Tatarstan, was carried out. The antibacterial activity of greater knapweed (Centaurea scabiosa L.), milk thistle (Silybum marianum (L.) Gaertn), scentless mayweed (Tripleurospermum inodorum (L.) Sch. Bip.), marsh cudweed (Gnaphalium uliginosum L.) against test strains of microorganisms – Clavibacter michiganensis VKM Ac-1404 (phytopathogenic gram-positive bacterium) and Alternaria solani St108 (phytopathogenic fungi) was established. The highest indices of inhibitory activity were found in the case of marsh cudweed - 0.0063%. The efficiency of pre-sowing treatment of seeds and foliar treatment of plants with an aqueous solution the potassium salts of terpene acids of Siberian cedar pine resin on the yield of winter wheat variety Kazanskaya-560 on gray forest soil at the Republic of Tatarstan was revealed. The yield increase was 3.7-3.9% to control. The grain size indicator (1000 grains weight) varied in the range of 36-38 g with the highest values in the case of pre-sowing treatment.

Reactions of two xeric-congeneric species of Centaurea (Asteraceae) to soils with different pH values and iron availability.

Centaurea scabiosa L. and C. stoebe Tausch are known to co-exist naturally in two extremely different types of open dry habitats in the temperate zone, alkaline xerothermic grasslands and acidic dry grasslands. However, knowledge about their preferences to edaphic conditions, including soil acidity (pH), and iron (Fe) availability is scarce. Therefore, experimental comparison of soil requirements (acidic Podzol vs alkaline Rendzina) of these species was carried out. The study was designed as a pot experiment and conducted under field conditions. Fe availability was increased by application of Fe-HBED. Reactions of plants to edaphic conditions were determined using growth measurements, leaf morphometric measurements, chlorosis scoring, chlorophyll content and chlorophyll a fluorescence (OJIP) quantification as well as determination of element content (Ca, Mg, Fe, Mn, Zn and Cu). Growth and leaf morphometrical traits of the studied congeneric species were affected similarly by the soil type and differently by the chelate treatment. Increased availability of Fe in Rendzina contrasted the species, as treatment with 25 µmol Fe-HBED kg−1 soil promoted growth only in C. stoebe. Both species turned out to be resistant to Fe-dependent chlorosis which was also reflected in only minor changes in chlorophyll a fluorescence parameters. Both species showed relatively low nutritional demands. Surprisingly, Fe-HBED did not stimulate Fe acquisition in the studied species, nor its translocation along the root:shoot axis. Furthermore, contrary to expectations, C. scabiosa took up less Fe from the acidic than alkaline soil. C. scabiosa not only absorbed more Ca and Zn but also translocated greater amounts of these elements to shoots than C. stoebe. Both species acquired more Mg on Podzol than on Rendzina which suggests adaptation allowing avoidance of aluminum (Al) toxicity on acidic soils. Overall, it seems that C. scabiosa prefers alkaline soils, whilst C. stoebe prefers acidic ones.

Comparative Assessment of the Phytochemical Composition and Biological Activity of Extracts of Flowering Plants of Centaurea cyanus L., Centaurea jacea L. and Centaurea scabiosa L.

The data on the phytochemical composition and biological activity for flowering plant extracts of the genus Centaurea (Knapweed)—cornflower (Centaurea cyanus L.), brown knapweed (Centaurea jacea L.), and greater knapweed (Centaurea scabiosa L.), which are typical representatives of the flora in the middle belt of the Russian Federation, were obtained. For the first time, biologically active substances such as pyranone, coumaran (2,3-dihydrobenzofuran), and 5-hydroxymethylfurfural were identified in ethanol and methanol extracts of Centaurea scabiosa L. by gas chromatography–mass spectrometry. Catechol and α-amyrin were the major components of the ethanol extract from Centaurea cyanus L., and flavone was the major component of Centaurea jacea L. flower extract. The greatest antimicrobial activity against phytopathogens was detected in Centaurea scabiosa L. when extracting freshly harvested flower biomass with methyl tert-butyl ether at room temperature: the minimum inhibitory concentrations were 60–120 µg/mL, the minimum fungicidal concentration was 120 µg/mL, and the minimum bactericidal concentration was 250 µg/mL. The low antioxidant activity of the studied plant extracts was established using the maximum values of Centaurea jacea L. Ethanol extract of Centaurea cyanus L. flowers had low antimicrobial and antioxidant activity. The extracts showed no phytotoxicity to garden cress germination but inhibited the growth of juvenile plants, especially roots. The greatest phytotoxic effect was revealed with methyl tert-butyl ether, where the depression of growth indicators was 35% or more.

Where trees cannot grow – Particulate matter accumulation by urban meadows

It has already been proven that trees and shrubs, can efficiently remove particulate matter (PM) from air. However, almost nothing is known about PM accumulation by herbaceous plants (grasses and forbs) found in urban meadows. Meadows, unlike trees and shrubs, can be located close to roads, one of the main sources of PM in cites. The aim of this study was to investigate the tolerance to urban condition and PM accumulation in the immediate roads vicinity of selected plants species in urban meadows. PM accumulation of annual and perennial meadows was compared with that of lawns. Results were interpreted in the context of species composition, biomass production, soil conditions and ambient PM concentrations. Of the species grown in annual meadows, the highest PM accumulation was found in Achillea millefolium L., Chenopodium album L. and Echium vulgare L., while Centaurea scabiosa L., Echium vulgare L. and Convolvulus arvensis L. accumulated the largest amounts of PM in perennial meadows. PM deposition on plants was positively correlated with a feathery leaf shape. For species in the annual meadows, a positive correlation was also found between PM accumulation and the wax content on plants. The presence of hairs on leaves, leaf size and plant growth pattern had no effect on PM deposition on plants. PM accumulation in one square metre of urban meadow was on average greater than that of lawn, regardless of meadow species' composition, age and location. The greatest accumulation of PM was found in a perennial meadow with low biodiversity but the greatest biomass. It would appear that the biomass produced by meadows and canopy structure has a crucial impact on the amount of PM accumulated by meadow plants. The results obtained indicate that meadows could be an important element of nature-based solutions for mitigating air pollution in urbanised areas.

Functional packaging of seeds.

SummaryThe encapsulation of seeds in hard coats and fruit walls (pericarp layers) fulfils protective and dispersal functions in many plant families. In angiosperms, packaging structures possess a remarkable range of different morphologies and functionalities, as illustrated by thermo and hygro‐responsive seed pods and appendages, as well as mechanically strong and water‐impermeable shells. Key to these different functionalities are characteristic structural arrangements and chemical modifications of the underlying sclerenchymatous tissues. Although many ecological aspects of hard seed encapsulation have been well documented, a detailed understanding of the relationship between tissue structure and function only recently started to emerge, especially in the context of environmentally driven fruit opening and seed dispersal (responsive encapsulations) and the outstanding durability of some seed coats and indehiscent fruits (static encapsulations). In this review, we focus on the tissue properties of these two systems, with particular consideration of water interactions, mechanical resistance, and force generation. Common principles, as well as unique adaptations, are discussed in different plant species. Understanding how plants integrate a broad range of functions and properties for seed protection during storage and dispersal plays a central role for seed conservation, population dynamics, and plant‐based material developments.

Frequency of flower visitors and achene production increase with rising population size in the self-incompatible herb Centaurea scabiosa (Asteraceae)

Self-incompatible, non-clonal plant species are especially dependent on the activity of flower visitors for seed production. Therefore, populations of these plants are vulnerable to a reduced flower visitation rates, but also to increased isolation by extinction of local populations. To study how local populations of Centaurea scabiosa, a self-incompatible, bee-pollinated herb species changed over time in the region of Bonn, we collected historical population records in the area and investigated their current status. We found that more than half of the subpopulations mentioned in the literature between 1950 and 2012 (38 of 65) have since disappeared. Small populations were most vulnerable, whereas medium to large populations increased in size. In a second step, we studied visitation frequencies and achene production and weight across 14 extant populations. We found that both flower visitation frequency and achene production were positively related to population size. Achene weight was neither related to the frequency of flower visitors nor to achene production. These results clearly indicate that reduced pollen transfer and lower pollination rates may contribute to local extinction in small populations of Centaurea scabiosa. Overall our results call for an intensified monitoring of the populations of self-incompatible plant species.

Evaluation of the Floristic Composition and Soil Properties of Grasslands in the Mohelno Serpentine Steppe 20 Years Since the Reintroduction of Sheep Grazing

In the paper there is evaluated floristic composition and soil characteristics of grasslands in the Mohelno Serpentine Steppe, where the sheep grazing was renewed after ca 60 years in 1997. Soil samples were collected in spring 2016 from 9 permanent plots MHS 1-9 in the same date as the phytocoenological releves were conducted. In the soil there was determined the soil acidity and the content of macro- and micronutrients. Data were evaluated using RDA (redundance analysis). It was found the higher dominance of species such as: Plantago lanceolata L., Festuca pseudovina Hack. ex Wiesb., Achillea collina Heimerl, Cerastium arvense L. and Centaurea scabiosa L. by higher content of basic macronutrients (N, P, K) in the soil. There is was apparent tendency for the decrease in the species diversity connected with increasing soil nutrient content.

Nitrogen signals and their ecological significance for seed germination of ten psammophilous plant species from European dry acidic grasslands.

The presented study evaluated effects of potassium nitrate (KNO3), ammonium nitrate (NH4 NO3) and ammonium chloride (NH4Cl) on the germination-related characteristics of 10 species from European dry acidic grasslands. Germination was studied under controlled laboratory conditions. The seeds were subjected to KNO3, NH4 NO3 and NH4Cl in four doses (1, 10, 50 and 100 mM) and to distilled water. Final germination percentage, index of germination velocity and index of germination synchrony were determined. Content of nitrogen in the soil probed from the site of seeds collection was also analyzed. Significant effects of type of the nitrogen compounds and their concentrations were observed. High concentrations of nitrogen-containing salts inhibited completion of germination in almost all species. Helichrysum arenarium and Hypericum perforatum showed preference for NH4+ over NO3‒, whereas Arnoseris minima, Alyssum montanum, Jasione montana and Spergula morisonii showed preference for NO3‒ over NH4+. Centaurea scabiosa, C. stoebe and Hypochaeris radicata had no preference and wide tolerance to the type of nitrogen-containing compound. Echium vulgare showed differential response hard for interpretation. A. montanum and J. montana showed stenotopic behavior in terms of nitrogen-related conditions. It is proposed that nitrogen-rich soil gaps favor establishment of more nitro-tolerant plant species (e.g. C. scabiosa, C. stoebe and H. radicata) as compared to nitrogen-poor ones.

АНТИМИКРОБНАЯ АКТИВНОСТЬ И ФИТОТОКСИЧНОСТЬ ЭКСТРАКТОВ НЕКОТОРЫХ ВИДОВ РАСТЕНИЙ РОДА CENTAUREA

The article presents data on the phytochemical composition and biological activity of extracts of plants of the genus Cornflower (Centaurea L.) - blue cornflower (Centaurea cyanus L.), meadow cornflower (Centaurea jacea L.), rough cornflower (Centaurea scabiosa L.), which are typical representatives flora of the middle zone of the Russian Federation, to assess the potential effectiveness of their use as plant protection drugs against phytopathogenic infections. The ethanol extracts were obtained by maceration of freshly harvested flowers, followed by filtration of the extract and concentration with the help of a rotary evaporator. The chemical composition of ethanol extracts was studied with the help of the gas chromatography/mass spectrometry (GC/MS) method. The qualitative and quantitative composition of the components differed depending on the plant types. The largest number of compounds was identified in the plant extract of cornflower rough, the seven components prevailing – coumaran, L-arctigenin, stigmasterol, γ-sitosterol, α-amyrin, β-amyrin and tocopherol acetate. The bacteriostatic, bactericidal and fungicidal properties of the extracts varied over a wide concentration range of 0.6...20 mg/ml. The highest indicators of antibacterial activity were found in the rough cornflower - the minimum inhibiting and bactericidal concentrations were 0.6…5 mg/ml, the lowest in the meadow cornflower - 5...20 mg/ml, respectively. Clavibacter michiganensis was characterized by the highest sensitivity to the components of plant extracts. In the case of the phytopathogenic fungus, the growth-inhibiting antimicrobial activity of cornflower extracts was the same for all studied species, and the fungicidal activity was most pronounced in the meadow cornflower - the effective concentration was 1 mg/ml. Presowing treatment with ethanol extracts had an inhibitory effect on the germination of test plant seeds: at a concentration of 1 mg/ml, the germination of watercress decreased by 8...42% compared to the control, 10 mg/ml - by 30...100%. Presowing seed treatment inhibited the linear growth of watercress roots by 35...52% and the accumulation of raw biomass of seedlings and roots by 23...89%.

Influence of bacterial melanine on morphological indicators of seeds germination of high-decorative species of flora of Belarus

Aim. The purpose of the work is to study the effect of a biological product based on the melaninogenic strain of Bacillus thuringiensis on germination and morphological parameters of highly decorative species of the flora of Belarus, promising for landscaping in the urban environment. Methods. Seed germination in laboratory conditions used with soaking in solutions of bacterial melanin in concentrations of 0.04, 0.025, 0.01%. Water and Terrasil at a concentration of 0.01 was used for a comparative evaluation of the effectiveness. Results. Morphological parameters were estimated during germination of the seeds of Verbascum thapsus L., Verbascum nigrum L., Centaurea scabiosa L., Betonica officinalis L., Viscaria vulgaris Bernh. treated with various concentrations of the stimulant. Conclusions. The effect of the bacterial melanin on the morphological parameters of plants was species- and dospecific. The optimal concentration for use on the studied plants should include concentrations up to 0.025%. The most pronounced effect of the use of the drug was revealed in the first days of seed germination, which allows the use of bacterial melanin to increase the germination of seedlings.
 Keywords: bacterial melanin, stimulant, seed germination, highly decorative species of flora.

COMPARATIVE PHARMACOGNOSTIC RESEARCH OF CENTAUREA SCABIOSA L. WILD-GROWING AND CULTI-VATED IN THE CONDITIONS OF TOMSK

The purpose of this study is: on the basis of a comparative study of the biological characteristics and chemical composition of Centaurea scabiosa L. wild-growing and cultivated, to assess the prospects for its introduction into culture as an additional source of raw materials for the anthelmintic drug development. It has been established that the Centaurea scabiosa L. cultivated under the conditions of the Tomsk city in terms of developmental phenology is close to a wild-growing plant. The vegetative organs ratios of wild-growing and cultivated plants were determined: leaves constitute 10% and 24%; baskets – 37% and 24%; stems up to 0.5 cm of thick –18% and 20%; stems with a thickness of more than 0.5 cm – 34% and 31%, respectively (beginning of flowering phase). The cultivated Centaurea scabiosa L. is comparable to a wild-growing plant according to the sesquiterpene lactones content in separated organs. The sesquiterpene lactones maximum amount accumulates in the budding phase, decreases slightly at the beginning of flowering, and significantly decreases at the mass flowering phase. The Centaurea scabiosa L. harvesting periods (the leafiest shoots with a stem diameter of not more than 0.5 cm) are experimentally substantiated – the phase of flowering onset.