Search

A series of greenhouse experiments was conducted to evaluate the effect of Plasmodiophora brassicae virulence on clubroot development and propagation of resting spores in 86 plant species from 19 botanical families. Plants were artificially inoculated with two isolates of P. brassicae, which were virulent on clubroot-resistant oilseed rape cultivar Mendel [pathotype 1; P1 (+)] or avirulent on this cultivar (P1). Clubroot severity and the number of resting spores inside the roots were assessed 35 days post inoculation. Typical clubroot symptoms were observed only in the Brassicaceae family. P1 (+)–inoculated species exhibited more severe symptoms (two- to 10-fold more severe), bigger galls (1.1- to 5.8-fold heavier), and greater numbers of resting spores than the P1-inoculated plants. Among all Brassica species, Bunias orientalis, Coronopus squamatus, and Raphanus sativus were fully resistant against both isolates, whereas Camelina sativa, Capsella bursa-pastoris, Coincya monensis, Descurainia sophia, Diplotaxis muralis, Erucastrum gallicum, Neslia paniculata, Sinapis alba, Sinapis arvensis, Sisymbrium altissimum, Sisymbrium loeselii, and Thlaspi arvense were highly susceptible. Conringia orientalis, Diplotaxis tenuifolia, Hirschfeldia incana, Iberis amara, Lepidium campestre, and N. paniculata were completely or partially resistant to P1 isolate but highly susceptible to P1 (+). These results suggest that the basis for resistance in these species may be similar to that found in some commercial cultivars, and that these species could contribute to the buildup of inoculum of virulent pathotypes. Furthermore, the pathogen DNA was detected in Alopecurus myosuroides, Phacelia tanacetifolia, Papaver rhoeas, and Pisum sativum. It can be concluded that the number and diversity of hosts for P. brassicae are greater than previously reported.

Purpose. Determine a number of morphometric and biochemical parameters of various genotypes of Bunias orientalis L. in the M. M. Gryshko National Botanical Garden of the NAS of Ukraine (NBG). Methods. Plant samples of B. orientalis (6 genotypes created in the NBG) were examined during the flowering stage. Determination of dry matter, ash, calcium was carried out according to Hrytsaienko et al. (2003), phosphorus according to Pochinok (1976), sugars, ascorbic acid and lipids were determined according to Krishchenko (1983), b-carotene according to Pleshkov (1985). The energy value of plants was determined using an IKA C-200 calorimeter. The obtained results were analysed statistically. Results. The height of plants varied from 140.9 (Genotype 1) to 157.5 (Genotype 5) cm, stem diameter from 11.67 (Genotype 1) to 16.1 (Genotype 6) mm, the number of internodes from 18.7 (Genotype 1) to 25.7 (Genotype 6), the number of leaves on a stem from 14.11 (Genotype 1) to 21.8 (Genotype 5), leaf lamina length from 14.2 (Genotype 1) to 23.45 (Genotype 6) cm, leaf lamina width from 6.34 (Genotype 1) to 14.5 (Genotype 4) cm, inflorescence length from 27.4 (Genotype 1) to 45.4 (Genotype 3) cm, inflorescence width from 2.32 (Genotype 1) to 4.92 (Genotype 3) cm, and the number of stems from 2.55 (Genotype 2) to 5.33 (Genotype 1). The study of the content of structural and functional compounds and nutrients at the flowering stage showed that the dry matter content was in the range of 13.58–16.00%, sugars 5.07–8.86%, titratable acidity 3.28–4.25%, lipids 3.33–6.61%, ascorbic acid 382.83–693.82 mg%, b-carotene 0.94–3.48 mg%, ash 6.79–9.2%, calcium 1.00–2.44%, phosphorus 1.61–2.67% and energy value 3337.0–3498.0 cal/g. Conclusions. It was revealed that samples of various genotypes of B. orientalis are a valuable source of nutrients at the flowering stage. The biochemical composition of plants depended on the genotype and stage of growth. Results of the morphometric study showed variability of investigated parameters. The obtained data can be used to predict and evaluate the results of introduction and breeding studies with B. orientalis genotypes as promising crops in Ukraine.

Purpose. Determine a number of morphometric and biochemical parameters of various genotypes of Bunias orientalis L. in the M. M. Gryshko National Botanical Garden of the NAS of Ukraine (NBG). Methods. Plant samples of B. orientalis (6 genotypes created in the NBG) were examined during the flowering stage. Determination of dry matter, ash, calcium was carried out according to Hrytsaienko et al. (2003), phosphorus according to Pochinok (1976), sugars, ascorbic acid and lipids were determined according to Krishchenko (1983), b-carotene according to Pleshkov (1985). The energy value of plants was determined using an IKA C-200 calorimeter. The obtained results were analysed statistically. Results. The height of plants varied from 140.9 (Genotype 1) to 157.5 (Genotype 5) cm, stem diameter from 11.67 (Genotype 1) to 16.1 (Genotype 6) mm, the number of internodes from 18.7 (Genotype 1) to 25.7 (Genotype 6), the number of leaves on a stem from 14.11 (Genotype 1) to 21.8 (Genotype 5), leaf lamina length from 14.2 (Genotype 1) to 23.45 (Genotype 6) cm, leaf lamina width from 6.34 (Genotype 1) to 14.5 (Genotype 4) cm, inflorescence length from 27.4 (Genotype 1) to 45.4 (Genotype 3) cm, inflorescence width from 2.32 (Genotype 1) to 4.92 (Genotype 3) cm, and the number of stems from 2.55 (Genotype 2) to 5.33 (Genotype 1). The study of the content of structural and functional compounds and nutrients at the flowering stage showed that the dry matter content was in the range of 13.58–16.00%, sugars 5.07–8.86%, titratable acidity 3.28–4.25%, lipids 3.33–6.61%, ascorbic acid 382.83–693.82 mg%, b-carotene 0.94–3.48 mg%, ash 6.79–9.2%, calcium 1.00–2.44%, phosphorus 1.61–2.67% and energy value 3337.0–3498.0 cal/g. Conclusions. It was revealed that samples of various genotypes of B. orientalis are a valuable source of nutrients at the flowering stage. The biochemical composition of plants depended on the genotype and stage of growth. Results of the morphometric study showed variability of investigated parameters. The obtained data can be used to predict and evaluate the results of introduction and breeding studies with B. orientalis genotypes as promising crops in Ukraine., Мета. Визначити деякі морфометричні та біохімічні параметри генотипів Bunias orientalis L. у Національному ботанічному саду імені М. М. Гришка НАН України (НБС). Методи. Рослинну сировину B. orientalis досліджували в період квітування (6 генотипів власної селекції НБС). Визначення сухої речовини, золи, кальцію проводили згідно з Грицаєнко та ін. (2003), фосфор – згідно з Починком (1976), цукри, аскорбінову кислоту та ліпіди – згідно з Крищенком (1983), b-каротин – згідно з Плєш­ковим (1985). Енергетична цінність визначалась на кало­риметрі IKA C-200. Дані проаналізовано статистично. Результати. Висота рослин становила від 140,9 (генотип 1) до 157,5 (генотип 5) см, діаметр стебла – від 11,67 (генотип 1) до 16,1 (генотип 6) мм, кількість міжвузлів – від 18,7 (генотип 1) до 25,7 (генотип 6) шт., кількість листків на стеблі – від 14,11 (генотип 1) до 21,8 (генотип 5) шт., довжина листкової пластинки – від 14,2 (генотип 1) до 23,45 (генотип 6) см, ширина листкової пластинки – від 6,34 (генотип 1) до 14,5 (генотип 4) см, довжина суцвіття – від 27,4 (генотип 1) до 45,4 (генотип 3) см, ширина суцвіття – від 2,32 (генотип 1) до 4,92 (генотип 3) см та кількість стебел – від 2,55 (генотип 2) до 5,33 (генотип 1) шт. Дослідження поживних речовин у період квітування показало, що вміст сухої речовини становив 13,58–16,00%, цукрів – 5,07–8,86%, титрована кислотність – 3,28–4,25%, ліпідів – 3,33–6,61%, аскорбінової кислоти – 382,83–693,82 мг%, b-каротину – 0,94–3,48 мг%, золи – 6,79–9,2%, кальцію – 1,00–2,44%, фосфору – 1,61–2,67%, енергетична цінність – 3337,0–3498,0 кал/г. Висновки. Рослинна сировина генотипів B. orientalis – цінне джерело поживних речовин у період квітування. Біохімічний склад рослин залежить від генотипу та фази розвитку. У результаті морфометричних вимірювань показано варіабельність досліджуваних параметрів. Отримані да­ні можуть бути використані для прогнозування та оці­нювання результатів інтродукційної і селекційної роботи з генотипами B. orientalis як перспективних культур в Україні.

Climate change is altering precipitation patterns, with higher frequency and magnitude of extreme events. Specifically, longer and more pronounced waterlogged conditions are predicted after rain spells as well as more frequent droughts, especially in Central Europe. Such hydrological changes can severely affect species performance and alter the function of ecosystems, as well as favor plant invasions. Competition with native communities may change depending on water stress. Bunias orientalis is an invasive plant that may benefit from disturbance or precipitation changes. We conducted a 3-year mesocosm experiment in a common garden to investigate how invasion success of B. orientalis in native German grassland communities is affected by varying hydrological conditions (from very dry to waterlogged). We measured the establishment and growth of B. orientalis in varying water table depths in bare soil (simulating disturbance) vs. in the community. Establishment and biomass of B. orientalis was generally highest under non-stress conditions. The species was also highly tolerant to dry conditions, but only when growing in bare soil. However, performance of B. orientalis was generally low, whereby interspecific competition in communities greatly limited invasion success. This might be due to the low competitive ability of the species in conditions of hydrological stress and the near-natural grassland communities with an extensive mowing regime used in our experiment. Our results suggest that invasion success of B. orientalis in grasslands will not increase if precipitation patterns change toward more extreme events. However, disturbance that creates bare soil patches might favor B. orientalis under drought conditions.

Проведено изучение научной литературы, где был анализ, показывающий содержание ценных БАВ разных групп в исследуемом сырье. Проведен качественный анализ сырья, в ходе которого было доказано наличие дубильных веществ реакцией с FeCl3, а также флавоноидов, реакцией с NaOH, а также цианидиновой пробой. При изучении микропрепарата листа с поверхности были идентицированы: 1) характерные вильчатые простые волоски на обеих сторонах листа, 2) извилистые жилки спиралевидной формы, A study of the scientific literature was performed, where there was an analysis showing the content of valuable biologically active substances of different groups in the studied raw materials. A qualitative analysis of the raw material was carried out, after which the presence of tannins was proved by reaction with FeCl3, as well as flavonoids, reaction with NaOH, and also a cyanidin breakdown. During the research of the micropreparation of the leaf surface, the following items were identified: 1) characteristic forked simple filaments on both sides of the leaf, 2) winding veins of spiral shape.

In the study natural plant communities appearing at the first stages of vegetation recovery in open cuts are described. Sixty-three species of higher vascular plants were found, six of which are adventive (Bunias orientalis L., Cichorium intybus L., Cirsium arvense (L.) Scop., Melilotus albus Medik., Sedum spurium M.Bieb., Solidago canadensis L.). Species from the Asteraceae (15), Gramíneae (8), Fabáceae (7) families prevail. The predominant life form according to I. Serebryakov are long-rhizome. According to G. Zozulin’s classification, plants belonging to the meadow and birch formations are most common. The associations of Calamagrostis epigejos and Bromus inermis predominate. Cirsium arvense (L.) Scop., Heracleum sibiricum L., Campanula glomerata L. are single.

The paper presents the results of a biochemical study of the aerial overburden mass of the Bunias orientalis L., grown under the conditions of the middle taiga subzone of the Republic of Komi according to the terms of its harvesting. The mass fraction of flavonols during the vegetative period of plants has been determined. It has been established that in mass budding and mass flowering phases in the row-leaves-buds (or flowers) the mass fraction of flavonols increases from 0,25% to 6,06% and from 0,6 to 15,43%, respectively. It is shown that when plants migrate to mass flowering, a sharp increase in the content of flavonols in all the above-ground organs of the plant is observed. A particularly large increase in the mass fraction of flavonols has been detected in the flowers of the overbearing of the eastern plants in comparison with the buds. Unconditional maximum of the pool of flavonols is observed in the flowers of the plant (15,43%). But, taking into account the fact that the mass fraction of flowers on the generative shoot is no more than 3%, in the technological plan, a promising source of flavonols from the aboveground mass of the studied plant are the leaves and flowers collected during the flowering phase in the Komi Republic in the third decade of June-July.

The male butterfly Pieris napi produces the anti-aphrodisiac pheromone methyl salicylate (MeS) and transfers it to the female during mating. After mating she releases MeS, when courted by conspecific males, which decreases her attractiveness and the duration of male harassment, thus increasing her time available for egg-laying. In previous studies we have shown that males produced MeS from the amino acid L-phenylalanine (L-Phe) acquired during larval stage. In this study we show that adult males of P. napi can utilize L-Phe and aromatic flower volatiles as building blocks for production of anti-aphrodisiac pheromone and transfer it to females during mating. We demonstrate this by feeding butterflies with stable isotope labelled molecules mixed in sugar solutions, and, to mimic the natural conditions, we fed male butterflies with floral nectar of Bunias orientalis plants treated with labelled L-Phe. The volatiles from butterflies and plants were collected and identified by solid phase micro extraction, gas chromatography and mass spectrometry techniques. Since P. napi is polygamous, males would gain from restoring the titre of MeS after mating and the use of aromatic precursors for production of MeS could be considered as an advantageous trait which could enable butterflies to relocate L-Phe for other needs.

We analyzed the pollen content in the gut and on the body of hoverflies (Diptera: Syrphidae), mostly from three genera (Eristalis, Syrphus s. l., and Sphaerophoria) that visited flowers of two jointly flowering species of Apiaceae with indistinguishable pollen (Anthriscus sylvestris and Aegopodium podagraria) and of Bunias orientalis (Brassicaceae). Pollen compositions depended on the plant from which the flies were collected rather than on the insect genus. At the same time, individual preferences of the studied flies to food plant species were confirmed. The pollen compositions in the gut and on the body were weakly correlated. Two possible reasons for such a weak correlation are discussed: individual differences in the fly feeding habits and different time of pollen preservation in the gut and on the body.

Bunias orientalis is a highly vigorous weed and the powerful taproot makes control difficult. Taking action against unwanted plant species at the development stage where they have a minimum of energy stored in their below ground plant parts has been efficient. Both young and older plants of B. orientalis were studied in order to identify this stage. Root dry-weight as a measurement of stored energy and the sprouting ability from root sections were studied as well as the transport direction of carbohydrates within the plants by using the isotop 14C.

Small-scale soil disturbances by fossorial animals can change physical and biotic conditions in disturbed patches and influence spatial and temporal dynamics, and the composition of plant communities. They create regeneration niches and colonization openings for native plants and, according to the intermediate disturbance hypothesis, they are expected to increase plant community diversity. However, it also has been reported that increased disturbance resource availability and decreased competition with native species may result in the invasion of communities by alien plant species, as predicted by the fluctuating resources theory of invasibility. In this study, we investigated the importance of European mole disturbances for the invasion of semi-natural fresh meadows and pastures by the alien plant, Bunias orientalis, which has mainly spread throughout Central Europe on anthropogenically disturbed sites. We hypothesized that the invader, being particularly well adapted to anthropogenic disturbances, enters into dense vegetation of meadows and pastures mainly on mole mounds. To assess the seedling recruitment of B. orientalis in relation to disturbance, we counted the number of seedlings that emerged on molehills and control plots in meadows and pastures. The establishment of juvenile (0–1 year) rosette plants on and off molehills was surveyed on 5 × 5 m plots. In accordance with our hypothesis, mole disturbances were found to serve as a gateway for B. orientalis by which the invader may colonize semi-natural grasslands. The seedlings of the species emerged almost solely on molehills and the young rosettes were established predominantly on mole mounds. Although the seedling density did not differ significantly between the meadows and pastures, the number of established plants in the pastures was considerably higher. We suggest that the invasion by B. orientalis in pastures may be facilitated by vegetative regeneration following root fragmentation by sheep pasturing.

Whereas many studies have revealed mechanisms driving plant invasions between continents, research on intracontinental range expanders is scarce. Therefore, we studied genetic, chemical and ecological traits of a range-expanding Brassicaceae, assuming that high genetic diversity should maintain chemical variation, which potentially benefits the invasion success. Moreover, we expected that within-individual defence diversity plays an essential role in biotic interactions. We compared Bunias orientalis L. plants from 16 populations of native, invasive or exotic non-invasive origin. The genetic structure was investigated by analysing the plastid DNA and amplified fragment length polymorphisms. For characterisation of the leaf chemistry, metabolic fingerprinting and profiling of glucosinolates as defence compounds were performed. The plant defence potential was tested using the generalist herbivore Mamestra brassicae. We found two major genetic lineages, which were mirrored in distinct chemical fingerprints of the plants. Genetic differentiation patterns point to a multiple introduction history of B. orientalis underlying the range expansion. Moreover, the genetic distance between individuals was correlated with the distance in chemical features. Genetic diversity tended to be reduced in potential leading edge (exotic) populations and was positively associated with quantitative metabolic diversity. Concentrations of indole glucosinolates were elevated in non-native populations, and high glucosinolate diversity was associated with low herbivore survival. Synthesis. This study suggests that the invasion success of this species may be facilitated by high chemical variation within populations. Moreover, high defence diversity within individuals of a population might be the main factor reducing herbivory and can be more important than the total concentration of defences. The combination of genetic and chemical analyses combined with bioassays revealed to be a powerful tool to study the differentiation between native and non-native populations and should be applied more often to explore intraspecific divergence.

Various mechanisms can facilitate the success of plant invasions simultaneously, but may be difficult to disentangle. In the present study, plants of the range-expanding species Bunias orientalis from native, invasive and naturalised, not yet invasive populations were compared in a field common garden over two years. Plants were grown under two nitrate-regimes and multiple traits regarding growth, defence, antagonist loads and reproduction were measured. A rank-based clustering approach was used to assign correlated traits to distinct suites. These suites were analysed for “syndromes” that are expressed as a function of population origin and/or fertilisation treatment and might represent different invasion mechanisms. Indeed, distinct suites of traits were differentially affected by these factors. The results suggest that several pre-adaptation properties, such as certain growth characteristics and intraspecific chemical variation, as well as post-introduction adaptations to antagonists and resource availability in novel habitats, are candidate mechanisms that facilitate the success of invasive B. orientalis in parallel. It was concluded that rank-based clustering is a robust and expedient approach to integrate multiple traits for elucidating invasion syndromes within individual species. Studying a multitude of traits at different life-history and establishment stages of plants grown under distinct resource treatments reveals species-specific trade-offs and resource sinks and simplifies the interpretation of trait functions for the potential invasive success of plants.

We studied the invasive warty cabbage Bunias orientalis (Brassicaceae) in three geographically distinct areas. Using inter-simple sequence repeat fingerprinting, we analyzed warty cabbages, including non-native populations, from the eastern Baltic and western Siberian regions and native populations from southwestern Russia. The eastern Baltic region and western Siberia represent the two opposite directions of B. orientalis spread in climatically different zones. The genetic structures of the native and non-native B. orientalis populations were assessed through analysis of molecular variance (AMOVA) and the Bayesian clustering method and by determining the main measures of genetic diversity. AMOVA revealed considerable population differentiation in both the native and invasive ranges. Our results did not indicate a decrease in genetic diversity in the non-native populations of B. orientalis. Similar measures of genetic diversity and genetic structure were determined in the invasive populations in two geographically and ecologically distinct, non-native regions located in Europe and Asia. In both of these regions, higher genetic diversity was detected in the non-native populations than in the native region populations, which may be due to multiple introductions. However, Bayesian clustering analysis revealed slightly different sources of invasive populations in the two non-native regions. Genetic diversity patterns revealed the lack of isolation by distance between populations and confirmed the influence of anthropogenic factors on the spread of B. orientalis. The significance of native populations as germplasm resources for breeding is discussed.

Šiukštaitė L., Patamsytė J., Žvingila D., 2013: Impact of genetic and demographic factors on the expansion potential of alien species Bunias orientalis in the suburbs of Vilnius [Genetinių ir demografinių veiksnių įtaka svetimkraštės rūšies Bunias orientalis vienos populiacijos plitimo galimybėms]. - Both. Lith., 19(2): 111-119. Bunias orientalis L. (Brassicaceae) is an alien and already naturalized plant species in Lithuania. Our purpose was to assess genetic diversity and age structure within single Belmontas population of B. orientalis, using RAPD, ISSR assays and herbchronology analysis. Three selected RAPD primers produced 58 scorable DNA bands, 53.33% of which were polymorphic. RAPD analysis identified 31 DNA markers. Six ISSR primers produced 113 reliable bands, but the level of polymorphism was slightly lower (38.1%) than RAPD. The 43 ISSR markers were identified. DNA markers were used for analysis of population genetic structure. AMOVA revealed significant genetic differentiation (ΦPT = 0.11) among subpopulations of B. orientalis located on both riversides of the Vilnia River. UPGMA cluster analysis did not reveal identical individuals in the group of studied plants, which indicate that spreading by seeds prevails in Belmontas population. Based on herbchronology analysis, young individuals dominate and provide good perspectives for population spreading.

[KEYWORDS: Exotic invasive species Volatiles Plant preference–performance Host shift Multitrophic interactions Bunias orientalis] Exotic plants often generate physical and chemical changes in native plant communities where they become established. A major challenge is to understand how novel plants may affect trophic interactions in their new habitats, and how native herbivores and their natural enemies might respond to them. We compared the oviposition preference and offspring performance of the crucifer specialist, Pieris brassicae, on an exotic plant, Bunias orientalis, and on a related native plant, Sinapis arvensis. Additionally, we studied the response of the parasitoid, Cotesia glomerata to herbivore-induced plant volatiles (HIPV) and determined the volatile blend composition to elucidate which compound(s) might be involved in parasitoid attraction. On both host plants we also compared the parasitism rate of P. brassicae by C. glomerata. Female butterflies preferred to oviposit on the native plant and their offspring survival and performance was higher on the native plant compared to the exotic. Although, headspace analysis revealed qualitative and quantitative differences in the volatile blends of both plant species, C. glomerata did not discriminate between the HIPV blends in flight-tent bioassays. Nevertheless, parasitism rate of P. brassicae larvae was higher on the native plant under semi-field conditions. Overall, P. brassicae oviposition preference may be more influenced by bottom-up effects of the host plant on larval performance than by top-down pressure exerted by its parasitoid. The potential for dietary breadth expansion of P. brassicae to include the exotic B. orientalis and the role of top-down processes played by parasitoids in shaping herbivore host shifts are further discussed.

A virus was isolated, using mechanical inoculation, from hill mustard (Bunias orientalis L.) plants exhibiting yellow mottling and blistering on leaves, which were frequently accompanied by asymmetric leaf narrowing. It systemically infected certain plants from the family Brassicaceae (Brassica rapa, Bunias orientalis, Hesperis matronalis, Sinapis alba) as well as Cleome spinosa and Nicotiana clevelandii, and locally Atriplex hortensis, Chenopodium quinoa, Ch. amaranticolor, N. tabacum. In the sap, it maintained infectivity for 3-4 days and lost it after heating for 10 min. at a temperature of 55 - 60oC or when diluted with water at 10-3. Virus particles were thread- like with a length of 675 - 710 nm. Based on an analysis of biological properties of the pathogen, serological response, particle morphology and data from field observations, it was identified as an isolate of Turnip mosaic virus (TuMV), and hill mustard was recognised as a natural overwintering host for this pathogen.

The adventive fraction of the Middle Ural flora is represented by 328 species of vascular plants from 198 genera and 51 families. Most of the adventive plants are nonaggressive and form the group of epecophytes (41%); all these plants have been accidentally introduced into the Middle Ural flora (xenophytes). Ephemerophytes occupy second place in the number of species (27%). More than half of this group (60%) is represented by ergasiophytes. The maximum diversity of ephemerophytes is observed in the urban flora (26%) and along railways (23%). Colonophytes form a group of similar size (26%), and most of these species are introduced plants. Agriophytes (18 species, or 6%) represent the most aggressive group. Among them, 78% belong to xenophytes and 22% are ergasiophytes. Thirteen agriophyte species represent alien plants: Heracleum sosnowskyi, Artemisia absinthium, Conyza canadensis, Impatiens grandulifera, Bunias orientalis, Chenopodium album, Convolvulus arvensis, Echinocystis lobata, Hippophae rhamnoides, Elodea canadensis, Epilobium adenocaulon, Epilobium pseudorubescens, and Amelanchier spicata. Thus, alien plants are a minor component of the adventive flora of the Middle Urals (4%).

The article contains information about the records of 43 species of alien vascular plants made in the Yamalo-Nenets Autonomous District. Field surveys were carried out in 2012-2016. The detected invasive species were growing on wasteland, abandoned and new lawns, in ditches and on roadsides. A majority of the reported species (Avena fatua, A. sativa, Barbarea vulgaris., Brassica rapa, Bunias orientalis, Cannabis sativa, Cirsium arvense, Crepis tectorum, Cyanus segetum, Dactylis glomerata, Erodium cicutarium, Fallopia convolvulus, Geum aleppicum, Glechoma hederacea, Helianthus lenticularis, Lappula squarrosa, Lathyrus pratensis, Lepidium ruderale, Lycopersicon esculentum, Medicago falcata, Plantago media, Potentilla norvegica, Raphanus raphanistrum, Rubus idaeus, Rumex pseudonatronatus, Scorzoneroides autumnalis, Secale cereale, Silene tatarica, Solanum tuberosum, Sonchus arvensis, Trifolium hybridum, T. medium, Triticum aestivum, Tussilago farfara, Typha latifolia, Urtica dioica) have been previously known from a few locations in the district. Onobrychis viciifolia Scop. and Echium vulgare L. are new for the regional flora. There is little information in the literature and in herbaria about Hordeum jubatum, Lepidotheca suaveolens, Senecio vulgaris, Melilotus albus and M. officinalis in the Yamalo-Nenets Autonomous District. However, these species are getting successfully naturalized, turning into common synanthropic plants in settlements of the district. Data from the herbarium label, information on the distribution in the Yamalo-Nenets Autonomous District and, if necessary, brief comments on the distribution in Siberia with specification for Western Siberia are provided for each species.

Many plants have been intentionally or accidentally introduced to new habitats where some of them now cause major ecological and economic threats to natural and agricultural ecosystems. The potential to become invasive might depend on plant characteristics, as well as on specific interactions with other organisms acting as symbionts or antagonists, including other plants, microbes, herbivores, or pollinators. The invasion potential furthermore depends on abiotic conditions in the habitat. Several species of the Brassicaceae, well known for their glucosinolate-myrosinase defence system, are invasive species. Various factors are reviewed here that might explain why these species were so successful in colonising new areas. Specific emphasis is laid on the role of glucosinolates and their hydrolysis products in the invasion potential. This particular defence system is involved specifically in plant-plant, plant-microbe and plant-insect interactions. Most research has been done on the mechanisms underlying invasion success of Alliaria petiolata and Brassica spp., followed by Bunias orientalis and Lepidium draba. Some examples are also given for plants that are not necessarily considered as invasives, but which were well investigated with respect to their interference potential with their biotic environment. For each species, most likely a combination of different plant characteristics enhanced the competitive abilities and led to diverse invasive phenotypes.

Summary 1 The EICA (evolution of increased competitive ability) hypothesis suggests that release from natural enemies and pathogens results in higher vigour of invasive plants as a result of the selection of less defended but rapidly growing genotypes. Slug diversity and abundance appear to be low in North America compared with Europe, and we therefore hypothesized that release from slug herbivory contributes to the invasiveness of European Brassicaceae species in North America. 2 In common garden and glasshouse experiments we compared life history and fitness parameters in native (NP) and introduced (IP) provenances of four invasive Brassicaceae species (Barbarea vulgaris, Bunias orientalis, Cardaria draba, Rorippa austriaca) that were subjected to herbivory by Arion lusitanicus. In climate chamber bioassays we investigated slug damage to seedlings and leaf discs using the same sources of plant material. 3 In all species except B. orientalis we found significant but not always consistent differences in growth and reproductive characteristics between IP and NP plants. Plants of B. vulgaris and R. austriaca from the introduced range had a considerably higher growth rate than those from the native range. While IP plants of the non-clonal B. vulgaris allocated more resources to seed production than NP plants, the IP plants of the clonal R. austriaca showed a decreased number of seeds. 4 Contrary to expectation, there were no differences between NP plants and IP plants in the number of damaged leaves and leaf area consumed by slugs, or in the proportion of seedlings damaged and killed. Nor were there interaction effects between slug treatments and provenance. 5 The results suggest that there are genetically based differences in growth and reproductive parameters between NP and IP plants. As there were no differences in herbivore damage between the provenances, this genetic differentiation is probably due to factors such as competition rather than herbivore effects. 6 In order to make progress in understanding why some species become invasive, more comparative experimental studies are needed that investigate how different kinds of antagonists (generalist and specialist herbivores and pathogens) influence the performance of plants at different life stages.

While it is widely accepted that disturbance often promotes the process of plant invasion, few data are available on specific relationships between different types of disturbance and success of plant invaders. Nor is much known about variation in invader behaviour in response to changing composition of the dominant native species in the recipient habitats. In the middle Main valley near Wurzburg (Germany), two invasive Brassicaceae forbs, Bunias orientalis and Rorippa austriaca , are frequently associated with a small number of dominant native species in the herbaceous vegetation of productive, disturbed sites. Variation in the relative dominance of these species suggests high variability between sites in the factors influencing the local invasion process. In our study, we examined variation in regeneration mode, type and frequency of disturbance, and native species composition, and considered life history differences between the two invasive species as factors contributing to the distinct dominance patterns. These factors were tested in a controlled field experiment in which individuals of the two invasive species and four native species were grown in mixed stands for almost 3 years. The development of the plants was monitored by cover values and all plants were harvested at the end of the study. All factors investigated contributed considerably to the development of distinct dominance patterns in the species mixtures. Relative to the natives, both invasive species were promoted by regeneration from vegetative fragments as compared to development from sexual offspring. While both invasive species were generally promoted by disturbance relative to the natives, they differed in their response to distinct types of disturbance, and these differences were strongly affected by species composition. Our results indicate that invasion success of R. austriaca may depend more on soil disturbance, soil transport and deposition, while B. orientalis is expected to particularly expand at mown sites that do not have dense cover by meadow grasses. Whether the native resident vegetation is mainly composed of successional competitors that suffer from disturbance or of ruderal competitors that compete early and strongly with the invasive species may be of critical importance for invasion by the two species.

The Turkish warty cabbage (or Russian old man) Bunias orientalis (Linnaeus 1753) is an extremely succcesful invasive plant species, which has firmly established itself in many central European habitats, and is rapidly expanding. For the first time, the nectar production and pollinators of this plant species are described, in order to predict its value as a food source for native insects. In addition, this study aims to predict possible competitive interactions with native plants in the context of pollination. It was found that nectar production per flower in B. orientalis is relatively low. However, because of the extremely high number of flowers per plant and per area, this plant is a valuable food source for energetically demanding visitors such as bumble bees and honeybees. These are the most common visitors to B orientalis, even though classical pollination syndromes would categorise this flower as fly-pollinated. Since B orientalis is an attractive nectar source, it is conceivable that there is a negative impact of its presence on the fitness of native species, simply by depressing visitation frequencies to other species.

In two potentially competing herbaceous plants, the invasive Bunias orientalis L. (Brassicaceae) and the native Picris hieracioides L. (Asteraceae), seasonal changes in leaf CO2 gas exchange and plant growth were studied over an entire growing season from February 1998 to December 1998 in two experimental fields. The study was motivated by the hypothesis that pre-adaptive phenological displacement of alien species relative to the native flora may be an important reason for the observed expansion of B. orientalis in central Europe. We quantified the importance of phenological differences for annual carbon gain in both species by estimating total leaf carbon gain from the results of leaf CO2 exchange and changes in plant leaf area. Bunias orientalis achieved almost half of its annual carbon gain in the time between early September and December, when competition for light by other species, like P. hieracioides, is low. Our quantitative approach corroborates the notion that the phenological shift of a relatively poor competitor, such as B. orientalis, could be of great importance for the success as an invasive species.

The population history of a 9-year-old roadside population of the invasive plant Bunias orientalis was reconstructed by demographic analysis including size, position, age (determined by herbchronology) and RAPD-PCR patterns of individual plants. We evaluated emerging patterns of population growth and genetic structure during a full period of population development under typical site conditions (anthropogenic disturbance) and their possible consequences for the invasion potential of the species. The population has grown rapidly and continuously (though with slowing geometric population increase) during the 9 years since its foundation, filling the space available in the study area. Genetic variation (RAPD markers) was already high in the founder cohorts and remained at the same level throughout population development (variance fluctuations

The competitive abilities of six perennial ruderal plants of three different growth forms were compared via yield measures using an additive diallel experimental design with unbalanced mixtures (9:3 or 3:9 plants per pot, respectively). Thus, in a given mixture species A was grown in two configurations: three individuals in centre position of the pot together with nine plants of species B in border position and vice versa. Effect competitive abilities as well as response competitive abilities of the species were significantly related to canopy height and plant biomass. The species with lower rosette growth form and smaller biomasses were weaker competitors than the species possessing elevated canopies along with higher biomasses, whereas total leaf area was not significantly correlated with competitive ability between species. Species differences in competitive ability were stronger between the plants grown in the central position than between those grown in the border position. Furthermore, interactions between species-specific traits and configuration could be observed, indicating the importance of species proportions and arrangement patterns for evaluation of competitive outcome in the field. The degree of complete transitivity of the competitive network of the six ruderal species, which was significantly higher than expected under the null model in our experimental design, also seemed to depend on species proportions in mixture. Shifts in root:shoot ratio of the centre plants when faced with competition by the border plants were in the direction of higher shoot allocation for the weak competitors with rosette growth form irrespective of the neighbour species, except for Bunias orientalis, which showed a more plastic response. The stronger competitors showed higher root allocation (Urtica dioica) or were hardly affected at all. Consistent with the results of our experiment, the weaker competitors occur at rather frequently disturbed and therefore transient field sites whereas the stronger competitors predominate at infrequently disturbed sites during several phases of succession.

Although plant-herbivore-enemy interactions have been studied extensively in cross-continental plant invasions, little is known about intra-continental range expanders, despite their rapid spread globally. Using an ecological and metabolomics approach, we compared the insect performance of a generalist and specialist herbivore and a parasitoid, as well as plant defence traits, among native, exotic invasive and exotic non-invasive populations of the Turkish rocket, Bunias orientalis, a range-expanding species across parts of Eurasia. In the glasshouse, the generalist herbivore, Mamestra brassicae, and its parasitoid, Microplitis mediator, performed better on non-native than on native plant populations. Insect performance did not differ between the two non-native origins. By contrast, the specialist herbivore, Pieris brassicae, developed poorly on all populations. Differences in trichome densities and in the metabolome, particularly in the family-specific secondary metabolites (i.e. glucosinolates), may explain population-related variation in the performance of the generalist herbivore and its parasitoid. Total glucosinolate concentrations were significantly induced by herbivory, particularly in native populations. Native populations of B. orientalis are generally better defended than non-native populations. The role of insect herbivores and dietary specialization as a selection force on defence traits in the range-expanding B. orientalis is discussed.

Phenological development of the colonizer Bunias orientalis L. was investigated in permanent plots in herbaceous vegetation, using photography and image analysis. In all habitats but one, B. orientalis showed a two-phased rosette growth behaviour, with a first peak cover reached in spring, roughly coinciding with an early peak cover of the matrix vegetation, and a second autumn growth flush occurring in a phase of reduced matrix vegetation cover. This seasonally bimodal growth pattern of B. orientalis appears to partly compensate for its competitive inferiority in crowded herbaceous vegetation. Small or overshadowed individuals of this species particularly profit from higher above-ground performance or release from overlap in autumn. The significance of temporal niche separation for survival and growth of B. orientalis individuals varies with habitat conditions, being most apparent in occasionally disturbed habitats with a relatively low frequency of gap formation. Despite some limitations, image analysis proved to be useful for phenological investigations within herbaceous plant stands.

Restriction fragment length polymorphism and sequence analysis of PCR-amplified ribosomal DNA were used to identify and classify phytoplasmas associated with diseases of various wild and cultivated plants. The diseases examined were either not known before or the presumable causal agents were not yet identified and characterized or were only known from other geographic areas. New diseases examined were those causing virescence and phyllody of Bunias orientalis and Cardaria draba. Both were associated with strains of the aster yellows phytoplasma. The same type of aster yellows phytoplasma was also found to be associated with yellows and phyllody diseases of Portulaca oleracea, Stellaria media, Daucus carota ssp. sativus, and Cyclamen persicum. In German and French DNA samples from diseased Trifolium repens, the clover phyllody phytoplasma was identified, which could clearly be distinguished from other phytoplasmas of the aster yellows group. Strains of the stolbur phytoplasma were detected in big bud-affected tomatoes and almost exclusively in Convolvulus arvensis. In Cirsium arvense and Picris echioides two distinct phytoplasmas were identified which showed relationship to the sugarcane white leaf phytoplasma group but may represent a new group or subgroup. In Conyza (syn.: Erigeron) canadensis a phytoplasma of the X-disease group was detected. A strain from Gossypium hirsutum showed the same restriction profiles as the faba bean phyllody phytoplasma.

Herbivory induces direct resistance responses in plants that negatively affect subsequently colonizing herbivores. Moreover, eggs of herbivorous insects can also activate plant resistance, which in some cases prevents hatching larvae from feeding. Until now, plant-mediated effects of eggs on subsequent herbivory, and the specificity of such responses, have remained poorly understood. We studied the specificity and effects of plant resistance induced by herbivore egg deposition against lepidopteran larvae of species with different dietary breadths, feeding on a wild annual plant, the crucifer Brassica nigra. We examined whether this plant-mediated response affects the growth of caterpillars of a specialist (Pieris brassicae) that feeds on B. nigra leaves and flowers, and a generalist (Mamestra brassicae) that rarely attacks this wild crucifer. We measured growth rates of neonate larvae to the end of their second instar after the larvae had hatched on plants exposed to eggs vs. plants without eggs, under laboratory and semi-field conditions. Moreover, we studied the effects of egg deposition by the two herbivore species on plant height and flowering rate before and after larval hatching. Larvae of both herbivore species that developed on plants previously infested with eggs of the specialist butterfly P. brassicae gained less mass compared with larvae that developed on egg-free plants. Plants exposed to butterfly eggs showed accelerated plant growth and flowering compared to egg-free plants. Egg deposition by the generalist moth M. brassicae, in contrast, had no effect on subsequent performance by either herbivore species, or on plant development. Our results demonstrate that B. nigra plants respond differently to eggs of two herbivore species in terms of plant development and induced resistance to caterpillar attack. For this annual crucifer, the retardation of caterpillar growth in response to deposition of eggs by P. brassicae in combination with enhanced growth and flowering likely result in reproductive assurance, after being exposed to eggs from an herbivore whose larvae rapidly reduce the plant's reproductive potential through florivory.

Leaf extracts ofBunias orientalis were shown to inhibit seed germination of a variety of cultivar plant species and of species cooccurring withB. orientalis in the field. Root exudate solutions and leaf litter leachates ofB. orientalis were tested for their allelopathic activity using seedling growth assays. Additionally, in comparative seedling growth assays soil cores removed from denseB. orientalis stands were tested bimonthly for elevated allelopathic effects. The impact of root exudates on seedling growth was generally weak and varied between species. Similar results were obtained for the effect ofB. orientalis leaf litter leachates on seedlings grown in sand culture relative to the effect of leaf litter leachates of a plant species mixture. When soil as a growth substrate was used, no consistent differences in seedling growth were obtained between the two litter leachate treatments. In the soil core experiment seedlings grown in soil cores collected from a denseB. orientalis stand unexpectedly showed better performance than seedlings grown in soil cores collected from a nearby mixed plant stand withoutB. orientalis, at least in early spring and late autumn. Predominating nutrient effects are, therefore, assumed to conceal a potentially increased allelopathic effect of soil beneath denseB. orientalis stands. It is concluded that other factors than allelopathy must be investigated to explain the rapid establishment of dense stands of this alien plant species.

The polycarpic perennial Bunias orientalis L. (Brassicaceae) introduced to Central Europe in the 18th century recently entered a phase of rapid spread accompanied by sudden establishments of extensive dominance stands mainly on roadside locations. We studied vegetation structure and expansion rate of B. orientalis stands and performed a series of experiments to investigate key factors that underlie the colonizing and establishment of B. orientalis. Reiterated observations exposed a high current expansion rate of B. orientalis populations and vegetation surveys of B. orientalis stands showed that these stands were mainly composed of Artemisietea and Arrhenateretea species. Regeneration experiments with root fragments revealed high regeneration capacities: root fragments of 3 cm length showed 93% regeneration, varying water content (10-50% water loss) and separation into root cortex and root stele yielded regeneration of 30 to 50%. In a field study high regrowth after mowing with varying mowing intensity indicates B. orientalis to be well adapted to disturbed sites as its preferential locations for development of dominance stands. Vegetative growth parameters were studied in two controlled growth experiments with elevated nutrient availabilities. B. orientalis exhibited a high sensitivity to nutrient addition and rosette sizes of maximal 90 cm were reached. Biomass was comparable or even higher than that of native ruderals grown in the same experiment. Measurements of reproductive parameters revealed a high reproductive effort (0.2 to 0.45 g g(-1)) even under intense mowing regimes, resulting in a dense seed bank with maximal values of about 400 fruits (congruent to 550 seeds) l(-1) soil. With respect to colonization and establishment of B. orientalis the results of our study enable the formulation of three hypotheses.

In the cytological literature and text-books, the term cryptopolyploidy is mainly ignored and sometimes re-interpreted and often wrongly quoted from the point of view of historical accuracy. The paternity over this term should be ascribed to Chiarugi (1933), although Jaretzky (1928a, b), while investigating karyologically two species of the genus Bunias, B. orientalis and B. erucago, first advanced a concept of «verkappte Polyploidie» to indicate the occurrence of chromosomes of enlarged size hypothetically due to fusion of homologous members (Jaretzky's «Sammelchromosomen»). By such homologous chromosome fusion a polyploid karyotype could appear as a diploid karyotype. A pupil of Chiarugi, Roma Melinossi, reinvestigating the two species quoted by Jaretzky, Bunias orientalis and B. erucago, documented a quite different karyological state for these species, cf. Melinossi (1935, 1937), that is the presence of the same karyotype (2n=14) in both species and the occurrence of chromosome of doubled siz...

Studies on the ecological impacts of exotic invasive plants have mainly focused on inter-continental invasions. However due to global environmental changes, a rapid increase in intra-continental range-expanding plants has been observed. In this context, multitrophic interactions between exotic plants, native herbivores and their natural enemies have been largely ignored. This thesis aimed at examining how an exotic range-expanding plant interacts with aboveground insect herbivores and their natural enemies and how it can contribute to the successful establishment of the exotic plant. In addition, it examines how resistance traits of different populations of the range-expander affect the behaviour and performance of herbivores and their natural enemies in the new habitat. Bunias orientalis (Capparales: Brassicaceae) is perennial plant from extreme south-eastern Europe and Asia that has recently expanded its range and become invasive in northern and central parts of Europe. In the Netherlands, it is considered naturalized but non-invasive. Firstly, using a community approach, I found that Bu. orientalis suffered less herbivore damage and harboured smaller invertebrate communities than sympatric native Brassicaceae in the Netherlands. The exotic plant has been found of low quality for the larval growth of the specialist herbivore (Pieris brassicae). Furthermore, two of its gregarious parasitoids were differentially affected by the quality of the exotic plant. The pupal parasitoid (Pteromalus puparum) survived better than the larval parasitoid (Cotesia glomerata), and the latter parasitized less hosts on the exotic than on native plants. Therefore, the herbivore can be selected to adapt to the new plant by conferring an enemy free space to the herbivore. In this case, a plant shift by the specialist herbivore might occur and thus preventing the further spread of the exotic plant. Conversely, in the field I found greater carnivore pressure on Bu. orientalis compared to other native Brassicaceae, particularly in the peak of arthropod abundance. Hence, top-down forces exerted by herbivore natural enemies may act in concert with bottom-up control of plant resistance traits to counteract herbivore plant shift and promote the successful range expansion of the exotic plant. Secondly, using a biogeographical approach, I found a considerable intraspecific variation in defence traits (trichomes, glucosinolates, metabolic fingerprints) of Bu. orientalis populations from the native and the exotic range. Plants collected in the native range were better defended than their exotic conspecifics. This variation matched with the performance of a generalist herbivore (Mamestra brassicae) and its parasitoid (Microplitis mediator), which developed poorly in plants from the native range. The results suggest that the defensive mechanisms of Bu. orientalis might have been counter-selected during the range expansion of the exotic plant. Further studies, however, need to examine if enemy release in the new range is followed by an increase in performance of the exotic plant. Finally, a comparative study of multitrophic interactions, both above- and belowground, in the plant native range and along the transect of its range expansion can help to clarify the mechanisms underlying the invasive success of Bu. orientalis.

Studies on the ecological impacts of exotic invasive plants have mainly focused on inter-continental invasions. However due to global environmental changes, a rapid increase in intra-continental range-expanding plants has been observed. In this context, multitrophic interactions between exotic plants, native herbivores and their natural enemies have been largely ignored. This thesis aimed at examining how an exotic range-expanding plant interacts with aboveground insect herbivores and their natural enemies and how it can contribute to the successful establishment of the exotic plant. In addition, it examines how resistance traits of different populations of the range-expander affect the behaviour and performance of herbivores and their natural enemies in the new habitat. Bunias orientalis (Capparales: Brassicaceae) is perennial plant from extreme south-eastern Europe and Asia that has recently expanded its range and become invasive in northern and central parts of Europe. In the Netherlands, it is considered naturalized but non-invasive. Firstly, using a community approach, I found that Bu. orientalis suffered less herbivore damage and harboured smaller invertebrate communities than sympatric native Brassicaceae in the Netherlands. The exotic plant has been found of low quality for the larval growth of the specialist herbivore (Pieris brassicae). Furthermore, two of its gregarious parasitoids were differentially affected by the quality of the exotic plant. The pupal parasitoid (Pteromalus puparum) survived better than the larval parasitoid (Cotesia glomerata), and the latter parasitized less hosts on the exotic than on native plants. Therefore, the herbivore can be selected to adapt to the new plant by conferring an enemy free space to the herbivore. In this case, a plant shift by the specialist herbivore might occur and thus preventing the further spread of the exotic plant. Conversely, in the field I found greater carnivore pressure on Bu. orientalis compared to other native Brassicaceae, particularly in the peak of arthropod abundance. Hence, top-down forces exerted by herbivore natural enemies may act in concert with bottom-up control of plant resistance traits to counteract herbivore plant shift and promote the successful range expansion of the exotic plant. Secondly, using a biogeographical approach, I found a considerable intraspecific variation in defence traits (trichomes, glucosinolates, metabolic fingerprints) of Bu. orientalis populations from the native and the exotic range. Plants collected in the native range were better defended than their exotic conspecifics. This variation matched with the performance of a generalist herbivore (Mamestra brassicae) and its parasitoid (Microplitis mediator), which developed poorly in plants from the native range. The results suggest that the defensive mechanisms of Bu. orientalis might have been counter-selected during the range expansion of the exotic plant. Further studies, however, need to examine if enemy release in the new range is followed by an increase in performance of the exotic plant. Finally, a comparative study of multitrophic interactions, both above- and belowground, in the plant native range and along the transect of its range expansion can help to clarify the mechanisms underlying the invasive success of Bu. orientalis.