Vincetoxicum Species Research Articles

Mass spectrometry-based metabolomics for the elucidation of alkaloid biosynthesis and function in invasive Vincetoxicum rossicum populations

The genus Vincetoxicum includes a couple of highly invasive vines in North America that threaten biodiversity and challenge land management strategies. Vincetoxicum species are known to produce bioactive phenanthroindolizidine alkaloids that might play a role in the invasiveness of these plants via chemical interactions with other organisms. Untargeted, high-resolution mass spectrometry-based metabolomics approaches were used to explore specialized metabolism in Vincetoxicum plants collected from invaded sites in Ontario, Canada. All metabolites corresponding to alkaloids in lab and field samples of V. rossicum and V. nigrum were identified, which collectively contained 25 different alkaloidal features. The biosynthesis of these alkaloids was investigated by the incorporation of the stable isotope-labelled phenylalanine precursor providing a basis for an updated biosynthetic pathway accounting for the rapid generation of chemical diversity in invasive Vincetoxicum. Aqueous extracts of aerial Vincetoxicum rossicum foliage had phytotoxic activity against seedlings of several species, resulting in identification of tylophorine as a phytotoxin; tylophorine and 14 other alkaloids from Vincetoxicum accumulated in soils associated with full-sun and a high-density of V. rossicum. Using desorption-electrospray ionization mass spectrometry, 15 alkaloids were found to accumulate at wounded sites of V. rossicum leaves, a chemical cocktail that would be encountered by feeding herbivores. Understanding the specialized metabolism of V. rossicum provides insight into the roles and influences of phenanthroindolizidine alkaloids in ecological systems and enables potential, natural product-based approaches for the control of invasive Vincetoxicum and other weedy species.

1095. Vincetoxicum magnificum (Nakai) Kitag.: Apocynaceae

SummaryThe genus Vincetoxicum Wolf is one of the most species‐rich genera in the Apocynaceae and has diversified in Japan. Vincetoxicum magnificum (Nakai) Kitag. is a perennial herb endemic to Japan. Most Japanese Vincetoxicum species flower in summer to autumn, whereas V. magnificum flowers in spring. Here we provide images of Japanese Vincetoxicum species in their natural habitats and a colour painting, detailed illustrations, photos, and a full description of V. magnificum.

Recovery of lipophilic compounds of Vincetoxicum species by supercritical carbon dioxide extraction

In this study, the dried herb of three Vincetoxicum species was subjected to supercritical carbon dioxide (SC-CO2) extraction for the recovery and characterisation of lipophilic compounds. The differences in extraction yield were not remarkable for the analyzed species; however, the effect of herb harvesting time at different year was quite significant. Two times higher yields of lipids were obtained from the plants collected in September 2020 compared to those collected in June 2022, e.g., from 1.39 to 3.01%. Linoleic, linolenic, oleic and palmitic acids were the major fatty acids in the extracted oils. β-sitosterol was the major phytosterol (from 4.84 to 10.74 mg/g), followed by stigmasterol, while vitamin E (α-tocopherol) was the dominant tocopherol in Vincetoxicum species extracts.CO2 extracts had similar antioxidant capacity and total phenolic content determined by different methods. Isovaleric acid, butyrolactone, hexanoic acid were the major volatile components identified in almost all plants extracts, however based on the integrated peak area significant quantitative variations were observed for different species and harvesting period (year). In conclusion, this study is the first report on lipophilic fraction of Vincetoxicum species recovered by SC-CO2, which demonstrates the presence of various bioactive components in the studied botanicals.

HYPENA OPULENTA: A BIOLOGICAL WEED CONTROL AGENT FOR CONTROLLING AN INVASIVE WEED SPECIES, SWALLOW-WORT: A REVIEW

Biological weed control agents are eco-friendly measures of controlling various weed species. They are the living organisms which kill or suppress the growth of another organism. This paper aims at organizing the scientific research finding and providing information about biological control of an invasive weed species, Swallowwort of Southern Ottawa region of Canada. Hypena opulenta, leaf feeding moth (Lepidoptera: Erebidae) is an effective bio-agent for controlling invasive plant species, Swallowwort (Vincetoxicum). Vincetoxicum is native to Mediterranean regions of France, Italy, and Spain and typically grows in calcareous soils on forested slopes. It was introduced to North America (Ontario, Canada) in 19th century. It is found in wide range of habitat that is from agricultural field to the forests and plantations making several adverse impacts in the respective ecosystems of the region. Overwintering Pupa of Leaf feeding moth emerges as an adult and starts laying eggs after 2 days. Eggs are deposited on upper or under side of the main vein and petioles of leaves. Larvae of H. opulenta feed exclusively on newly expanded leaves of the plant for completion of its developmental cycle. Though the larvae show the minimal feeding on other plants but they necessarily require Vincetoxicum species as a host for completion of their life stages. Before releasing larvae of H. opulenta for control of Vincetoxicum in the field they were tested in the lab for host specificity and environmental safety. Larvae of H. opulenta can spread up to the distance of 100 m from release site and control the growth of swallow-wort by feeding on newly emerged leaves which results in reduced shoot biomass and seed multiplication of the plant.

Impact of Abrostola asclepiadis combined with other stressors on invasive swallow-worts (Vincetoxicum species)

The moth Abrostola asclepiadis (Lepidoptera: Noctuidae) is being investigated for biological control of pale and black swallow-wort (Vincetoxicum rossicum and V. nigrum, respectively; Apocynaceae), European vines introduced into North America. Limited information existed on its potential impact on swallow-worts, and the combination of defoliation damage by A. asclepiadis and other stresses to the plants had not been studied. We conducted greenhouse studies of the impact of different frequencies (once or twice) and degrees of defoliation (50 or 100%-seedlings; one or two larvae per stem-mature plants) by larvae on seedlings and mature (flowering) plants of black and pale swallow-wort. Defoliation was combined with varying light levels (shaded or not) or competition with quackgrass (Elymus repens). Significant reductions in aboveground dry mass and seeds generally only occurred when plants were completely defoliated twice. Grass competition and, to a greater extent, shading reduced growth and reproduction of swallow-wort plants. However, no interactions between defoliation and the other stressors occurred, suggesting they would have an additive effect. Because A. asclepiadis is likely to be univoltine if released in North America, its impact appears to be limited even if severe defoliation is achieved. Therefore, A. asclepiadis should be given a lower priority for release.

Identifying critical life stage transitions for biological control of long‐lived perennial Vincetoxicum species

Abstract Demographic matrix modelling of invasive plant populations can be a powerful tool to identify life stage transitions for targeted disruption, in order to cause population decline. This approach can provide quantitative estimates of reductions in select vital rates needed to reduce population growth rate (λ) below 1 and can inform the prerelease selection of effective biological control agents, as in the case of two invasive Vincetoxicum species in North America. We parameterized a five life stage matrix model using vital rate data from six populations (field and forest) of Vincetoxicum nigrum and Vincetoxicum rossicum. Elasticity analyses were used to identify life stage transitions and associated vital rates for perturbation through the incorporation of per capita impact data of candidate agents. Several survival, growth and fecundity‐related transitions were identified that were mostly similar across species, habitats and locations, although two populations showed unique population dynamics. Reductions in associated vital rates needed to prevent population growth varied greatly among populations. Defoliation damage and predispersal seed predation can be effective against slower growing forest and field populations of Vincetoxicum species. A fly and bivoltine moth are recommended as priority agents. However, biological control with these same agents will be ineffective against other field populations as well as some forest populations if the intensity of damage is not severe. Synthesis and applications. Control of long‐lived perennial plants, such as species of Vincetoxicum, is projected to occur through disruption of some individual vital rates of survival, growth or fecundity if population increase is low to moderate (λ < 1.6). However, without significant and simultaneous reductions in multiple lower level vital rates, faster growing populations will not be contained with biological control or other management tools.

Host specificity of Asian Chrysochus Chevr. in Dej. (Coleoptera, Chrysomelidae: Eumolpinae) and their potential use for biological control of invasive Vincetoxicum species

Three Asian leaf beetles of the genus Chrysochus were investigated as potential biological control agents of Vincetoxicum rossicum and V. nigrum, invasive weeds in northeastern North America. Chrysochus chinensis and Ch. globicollis were collected from a field host in a different genus and subtribe. Preliminary no-choice laboratory tests with Ch. goniostoma showed that its physiological host range is too broad. Based on these data, we are not considering these three species as potential biological control agents of invasive Vincetoxicum species.

Effects of temperature on pupal and egg development of Euphranta connexa, a candidate biological control agent for invasive swallow‐worts in North America

AbstractVincetoxicum rossicum (Kleopow) Barbar and Vincetoxicum nigrum (L.) (Apocynaceae) are invasive perennial weeds in North America, for which Euphranta connexa (Fabricius) (Diptera: Tephritidae) is a potential biological control agent. Female E. connexa oviposit in seed pods of European Vincetoxicum species, and developing larvae consume the seeds. Mature larvae emerge and form overwintering puparia in the soil. To facilitate laboratory rearing and the synchronization of oviposition and larval activity with vulnerable stages of target and non‐target plants, we investigated the effect of temperature on survival and development of E. connexa pupae and eggs. Field‐collected pupae from Switzerland were overwintered in cool storage and in spring, and they were placed in constant‐temperature treatments from 9.4 to 35 °C. Adults emerged at temperatures from 11.8 to 27.3 °C, and there was no evidence of pupal diapause. Rates of pupal development did not differ between sexes or among collection sites at altitudes ranging from 520 to over 1 700 m above sea level. From truncated normal models of development rate response to temperature, the estimated lower temperature threshold for pupal development was 4.2 °C and development was most rapid at 25.8 °C. When newly‐laid eggs were exposed to constant temperatures from 11.8 to 30 °C, hatch occurred at all temperatures. The estimated lower temperature threshold for egg development was 9.3 °C, and the predicted temperature at which egg development was most rapid was 31.2 °C. The models of pupal development suggest that E. connexa does not complete its life cycle at the highest altitude of our collection sites and that insects collected there were the result of dispersal from lower altitudes. The models predict that the northernmost North American sites where the insect might be released for biological control of invasive Vincetoxicum species are close to the northern limit for completion of the life cycle of E. connexa.

Impact of the defoliating moth Hypena opulenta on invasive swallow-worts (Vincetoxicum species) under different light environments

Black and pale swallow-wort (Vincetoxicum nigrum and Vincetoxicum rossicum, Apocynaceae) are twining vines from Europe that have become invasive in eastern North America. Hypena opulenta (Lepidoptera: Erebidae), a defoliating moth from the Ukraine, has recently been released in Canada and a request for release in the United States is under review. Its potential multivoltinism, and hence repeated defoliation of swallow-worts, combined with low-light levels in an understory environment may be promising for controlling forest infestations of swallow-worts. We conducted a greenhouse study of the impact of larval defoliation on seedlings and mature (flowering) plants of black and pale swallow-wort at different frequencies (once or twice) and degrees of defoliation (50 or 100%-seedlings; three or six larvae per stem-mature plants). Defoliation occurred under two forest light-regimes: low-light conditions typical of deeply-shaded forest habitats and higher light levels representative of a more open canopy or forest edge. Plants grown under higher light conditions were generally larger and produced many more seeds than heavily-shaded plants. One round of complete defoliation by H. opulenta, but not necessarily two, generally reduced biomass and seed production for both species and life stages, except for root mass of mature plants. No mature plants died and little seedling mortality occurred apart from black swallow-wort that had been completely defoliated twice under low light. Pale and black swallow-wort seedlings and mature plants appear to be tolerant of moderate defoliation damage. Complete defoliation repeated within and across years may be needed for suppression of forest infestations of swallow-wort.

Long-term persisting hybrid swarm and geographic difference in hybridization pattern: genetic consequences of secondary contact between two Vincetoxicum species (Apocynaceae–Asclepiadoideae)

BackgroundDuring glacial periods, glacial advances caused temperate plant extirpation or retreat into localized warmer areas, and subsequent postglacial glacial retreats resulted in range expansions, which facilitated secondary contact of previously allopatric isolated lineages. The evolutionary outcomes of secondary contact, including hybrid zones, dynamic hybrid swarm, and resultant hybrid speciation, depends on the strengths of reproductive barriers that have arisen through epistatic and pleiotropic effects during allopatric isolation. The aim of this study was to demonstrate refugia isolation and subsequent secondary contact between two perennial Asclepioid species and to assess the genetic consequences of the secondary contact. We modeled the range shift of two ecologically distinct Vincetoxicum species using the species distribution model (SDM) and assessed the genetic consequences of secondary contact by combining morphological and genetic approaches. We performed morphometric analysis (592 individuals) and examined 10 nuclear microsatellites (671 individuals) in V. atratum, V. japonicum, and putative hybrid populations.ResultsMultivariate analysis, model-based Bayesian analysis, and non-model-based discriminant analysis of principal components confirmed the hybridization between V. atratum and V. japonicum. High pollen fertility and a lack of linkage disequilibrium suggested that the hybrid populations may be self-sustaining and have persisted since V. atratum and V. japonicum came into contact during the post-glacial period. Moreover, our findings show that the pattern of hybridization between V. atratum and V. japonicum is unidirectional and differs among populations. Geographically-isolated hybrid populations exist as genetically distinct hybrid swarms that consist of V. atratum-like genotypes, V. japonicum-like genotypes, or admixed genotypes. In addition, Bayesian-based clustering analysis and coalescent-based estimates of long-term gene flow showed patterns of introgressive hybridization in three morphologically ‘pure’ V. japonicum populations.ConclusionIn this study, we demonstrated that climatic oscillations during the Quaternary period likely led to species range shift and subsequently secondary contact. Hybrid populations may be self-sustaining and have persisted since V. atratum and V. japonicum came into contact during the post-glacial period. Pattern of hybridization between V. atratum and V. japonicum is unidirectional and differs among populations. We concluded that these differences in the genetic consequences of secondary contact are caused by historical colonization processes and/or natural selection.Electronic supplementary materialThe online version of this article (doi:10.1186/s12862-016-0587-2) contains supplementary material, which is available to authorized users.

Establishment of the invasive perennial Vincetoxicum rossicum across a disturbance gradient in New York State, USA

Vincetoxicum rossicum (pale swallow-wort) is a non-native, perennial, herbaceous vine in the Apocynaceae. The species’ abundance is steadily increasing in the northeastern United States and southeastern Canada. Little is known about Vincetoxicum species recruitment and growth. Therefore, we conducted a field experiment in New York State to address this knowledge gap. We determined the establishment, survival, and growth of V. rossicum during the first 2 years after sowing in two old fields subjected to four disturbance regimens. We hypothesized that establishment and survival would be higher in treatments with greater disturbance. At the better-drained location, overall establishment was 15 ± 1% [mean ± standard error] and did not differ among treatments. At the poorly drained location, establishment varied by treatment; mowed and control plots had greater establishment [10 ± 2%] than herbicide + tillage and herbicide-only plots [1.6 ± 0.5%]. Of those seedlings that emerged, overall survival was high at both locations (70–84%). Similarly, total (above + belowground) biomass was greater in herbicide + tillage and herbicide-only plots than in mowed and control plots at both locations. Thus, V. rossicum was successful in establishing and surviving across a range of disturbance regimens particularly relative to other old field species, but growth was greater in more disturbed treatments. The relatively high-establishment rates in old field habitats help explain the invasiveness of this Vincetoxicum species in the northeastern U.S. and southeastern Canada.

Exomorphic seed characters and anatomy of leaf and stem of some Vincetoxicum (Asclepiadaceae/apocynaceae) species from Turkey

Vincetoxicum NM Wolf cinsine ait 5 taksonunun ekzomorfik tohum karakteristigi isik ve taramali elektron mikroskobu kullanilarak arastirilmistir. Bazi karakterlerin farkli taksonlarda degisiklik gosterdigi bulunmustur. Bunlar tohum sekli, tohum yuzeyindeki girinti ve cikintilardir. Diger karakterler ise tohum koma tuyleri, periklinal duvarlarin konkav/konveks olmalari ve antiklinal duvarlarin cesitli derinliklerdeki kanallaridir. Bitkilerin govde ve yapraklarinin anatomik karakterleri belirlenmistir. Calisilan taksonlar Asclepiadaceae familyasinin genel anatomik ozelliklerine sahiptir

Morphological aspects and phylogenetic analyses of pollination systems in the Tylophora-Vincetoxicum complex (Apocynaceae-Asclepiadoideae) in Japan

Pollinators of two Cynanchum, five Tylophora, and 16 Vincetoxicum species were observed in 26 populations in Japan. The following pollination systems were observed in 18 species: moth pollination, generalized insect pollination, wasp pollination, dipteran pollination, both dipteran and moth pollination, and autogamy. Principal component analysis based on 13 floral characters indicated that the size of the pollinator tended to increase with sizes of all characters measured. Furthermore, species that have developed interstaminal parts of the corona and concealed stigmatic chambers tend to be pollinated by long-tongued insects. The phylogenetic distribution of pollinator types showed that species belonging to Clade I are pollinated exclusively by Diptera, whereas those of Clade II are pollinated by four insect orders. The most prominent pollinator transition in the Tylophora–Vincetoxicum complex is dipteran to moth pollination. The most common morphological change of the plants from dipteran pollination to moth pollination, or vice versa, is modification of the corolla. In the Tylophora–Vincetoxicum complex, pollination mode shifts are generally accompanied by modifications of the corona and the structure of gynostegium. One hypothesis for the rapid radiation observed in Clade II is that a widely distributed species may have partitioned its distribution in the relatively near past and adapted to various environments, in which the dominant pollinators were different, and that the local races may then have diverged from each other after they were isolated. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society, 2008, 93, 325–341.

Monarch Butterfly Oviposition on Swallow-Worts (<I>Vincetoxicum</I> spp.)

As black swallow-wort, Vincetoxicum nigrum L. Moench, and pale swallow-wort, V. rossicum (Kleopow) Barbar., spread throughout the northeastern United States and southern Canada, there is concern about the impact of these invasive plants on populations of the native North American monarch butterfly Danaus plexippus L. Recent laboratory studies in New York and Ontario, Canada, have found little or no oviposition by monarch butterflies on the two Vincetoxicum species. In Rhode Island, we found 10.5-21.7% oviposition on Vincetoxicum species relative to common milkweed Asclepias syriaca L. in choice tests and 11.9-20.3% in no-choice tests in 2 yr of laboratory testing. These results were supported by field cage trials where monarchs given a choice between V. nigrum and A. syriaca laid 24.5% of their eggs on V. nigrum. In surveys of three pasture fields in Rhode Island where relative coverage of A. syriaca exceeded that of V. nigrum by a 0.77:0.23 ratio, 15.4% of monarch eggs were found on V. nigrum plants. In V. nigrum stands with very little A. syriaca (6.25 stems/ha), monarch egg density on V. nigrum was found to be over five times greater than in the three mixed pasture fields. In none of our laboratory or field evaluations was there any survival of monarch larvae on Vincetoxicum species. It seems that in Rhode Island, Vincetoxicum species serve as an oviposition sink for monarch butterflies. These findings suggest that East Coast butterflies may differ in host selection from those in central New York and southern Ontario, Canada.

Oviposition preference and larval performance of monarch butterflies (Danaus plexippus) on two invasive swallow‐wort species

AbstractThe potential of two invasive herbaceous vines Vincetoxicum nigrum (L.) Moench and Vincetoxicum rossicum (Kleopow) Barbar. (Asclepiadaceae) to reduce monarch butterfly (Danaus plexippus L.) (Lepidoptera: Nymphalidae, Danainae) populations was investigated by evaluating oviposition selection in adult monarch butterflies and larval feeding preference in choice tests comparing the native host plant of monarch butterflies, Asclepias syriaca L. (Asclepiadaceae) and the two non‐indigenous Vincetoxicum species. In both choice and no‐choice tests, no eggs were oviposited on either of the two Vincetoxicum species whereas over 66 eggs per female were oviposited on A. syriaca plants. All first instar larvae allowed to feed on A. syriaca for 48 h survived while a significantly lower proportion survived on V. rossicum (44%) and V. nigrum (14%). Mean weight of larvae that did survive on the Vincetoxicum species was significantly lower than the mean weight of larvae that fed on A. syriaca. The mean weight of surviving larvae, however, did not differ between the two Vincetoxicum species. The mean proportion of leaves consumed by larvae feeding on A. syriaca was significantly greater than the mean proportion of leaves consumed by larvae feeding on either Vincetoxicum species. Findings from this research indicate that V. rossicum and V. nigrum are not viable hosts of monarch butterflies and are likely to pose little direct threat to their populations as oviposition sinks. The ability of these highly aggressive plants, however, to out‐compete and displace the native host of monarchs, A. syriaca, may pose a more serious threat. The potential of monarch populations to adapt to the two Vincetoxicum species as host plants over the long‐term is discussed.

Cronartium flaccidum fruitbody production on Melampyrum spp. and some important alternate hosts to pine

Four Vincetoxicum species, Paeonia anomala and Melampyrum sylvaticum known to act as alternate hosts for Cronartium flaccidum, and a potential host Melampyrum pratense were inoculated either in vitro or in vivo with various aeciospore sources of C. flaccidum. All fresh C. flaccidum aeciospore sources variably produced uredia or telia on Vincetoxicum hirundinaria, Vincetoxicum mongolicum, Vincetoxicum fuscatum, Vincetoxicum nigrum, P. anomala, nine geographic provenances of M. sylvaticum, and two provenances of M. pratense. This is the first time that C. flaccidum telia were artificially produced on M. sylvaticum and the first time that M. pratense was shown to act as alternate host for C. flaccidum. The results suggest that M. sylvaticum is relatively susceptible to C. flaccidum, whereas M. pratense is almost resistant to this rust. The low host‐specificity of the Finnish population of C. flaccidum was demonstrated, as V. hirundinaria from Italy was susceptible to the rust.

The Distribution and Status of Species of Vincetoxicum in Eastern North America

SHEELEY, S. C. AND D. J. RAYNAL (College of Environmental Science and Forestry, State University of New York, Syracuse, NY 13210). The distribution and status of Vincetoxicum nigrum (L.) Moench, V. rossicum (Kleo.) Barb. and V. hirundinaria Medik. in eastern North America Bull. Torrey Bot. Club 123:148-156. 1996.Vincetoxicum nigrum (L.) Pers., (Kleo.) Barb., V. rossicum and V. hirundinaria Medik. (Asclepiadaceae) are exotic twining perennial herbs found in eastern North America. The nomenclatural status as well as the historical and current distribution of these plants were surveyed by studying floristic manuals of flora and journal literature and by examining herbarium specimens, and corresponding with authorities familiar with the species. Vincetoxicum rossicum is the most invasive of the species, often forming large colonies; it occurs from the northeastern Atlantic coast W to S Michigan and from S. Ontario to s. Pennsylvania. Vincetoxicum nigrum and V. hirduninaria appear less aggressive and have more limited patterns of distribution. Vincetoxicum nigrum occurs from the northeastern Atlantic Coast west to Missouri and Kansas and from southern Ontario to southern Pennsylvania. Vincetoxicum hirundinaria is found in southern Ontario, New York and Pennsylvania. Vincetoxicum species may persist for decades after establishment, spreading vegetatively and by means of polyembronic seeds.