Vincetoxicum Hirundinaria Research Articles

Identity and phylogenetic status of two sibling gall midge species (Diptera: Cecidomyiidae: Contarinia) on the perennial herb Vincetoxicum hirundinaria

Abstract Contarinia comprises one of the largest genera among gall forming midges of Cecidomyiidae, where identification and species relationships are uncertain. Using data on phenological development, morphometric relationships and mitochondrial DNA, the status of two isomorphic species, C. vincetoxici and C. asclepiadis, which attack the perennial herb Vincetoxicum hirundinaria, were investigated. Data show that they are two distinct species. In rearing experiments, the two gall midges were shown to have different times of adult emergence. Small differences in wing morphology were revealed that separate the two species from each other, as well as from C. loti, the type species of Contarinia. Sequence differences in the mitochondrial cytochrome b gene corroborate the specific status of C. vincetoxici and C. asclepiadis. Furthermore, a phylogenetic analysis, also including three other Contarinia species, showed that the two gall midges on V. hirundinaria are not even the most closely related species, suggesting two separate evolutionary colonizations of the host plant.

Data to the Biology of the Red Spotted Bug (Spilostethus [= Lygaeus] equestris L., Het., Lygaeidae) Causing the Achene Greening of Alimentary Cross-Bred Sunflower

Western European, and especially German-based multinational food processing companies tend to have “alimentary purpose” sunflower hybrlds and varieties grown in Hungary. This “commercial” product is highly preferred as Substitute of walnuts, or as filling in chocolate, bread, other bakery products, or baked into the top layer thereof. In early 1990s German companies rejected several truckloads of export goods due to “greening of the seed in the achene”. Almost 90% of the rejected consignments originated from the Sandy ridge of the region between the rivers Danube and Tisza, which is severely infected with Asclepias syriaca L weed. Field investigations revealed unambiguously that the greening of the seed in the achene had been caused by the Spilostethus [= Lygaeus] equestris L plant bug. This species is able to cause extensive damages and discontinuities in the so-called Shoulder part of the achene with its powerful stinging-suctorial mouth organ. In the damaged area of intensive Chlorophyll formation begins due to the solar effect, which is the unambiguous cause of the greening of the seed in the achene. In our investigations the industrial purpose sunflower plantations in two neighbouring areas (Bacsalmas and Katymar) were studied in respect of the damage caused by the Spilostethus [= Lygaeus] equestris L. While in Bacsalmas (that district was less infected with the Asclepias syriaca L) we found a damage of decreasing intensity (8.85 damaged achenes per sunflower disc) as advancing towards the centre of the plantation, while in the area of Katymar (this area was severely infected with Asclepias syriaca L), this value was almost three times as high, reaching 31.71 damaged achenes per disc. Though the numbers are not very high in themselves -assuming that a well-built disc contains 1100 to 1200 seeds -, but the damage may result in significant fall of quality, or even prevent exporting. Our extensive research into the causes of the greening of the sunflower seeds made it clear that the Spilostethus [- Lygaeus] equestris L has a significant influence on the contents of the seeds it has damaged: it increases the proportion of linoleic acid (C18:2) by about 2.5 %. That affects the lasting quality of the achene unfavourably (HORVATH & BUJAKI, 1991). For this reason, a comprehensive study of the biology of the Spilostethus /= Lygaeus] equestris L became necessary for the developing possible protection methods. Such studies also represented the beginning of the investigation of any external or endogenous factors, that might obstruct the successful use of alimentary purpose sunflower hybrids or varieties in the food industry. According to GUNTHER (1975), the S. equestris L is indigenous from southern England to Siberia, and from central Sweden to the Mediterranean areas. It is less common north of Central Europe; it prefers areas with warmer climate. It likes staying both on the ground or in the flowers of various plants. It especially likes the tarne poison or swallowwort (Vincetoxicum officinale MNCH., syn.: Cynanchum vincetoxicum (L) PERS.). Data on the way of life of the S. equestris L in Hungary is extremely scarce, despite the fact that the species is widespread in our country. Information on its nourishing plants and habits can only be found in the publications of HORVATH (1984; 1986; 1987b; 1989; 1999) and BUJAKI & HORVATH (1992). Horvath (1984) inferred the nourishing plant specialization of the species from the total nitrogen contents of various plant seeds, such as those of the Asclepias syriaca L, and the sunflower (Helianthus annuus L). Amino-acid composition in the seeds of the A. syriaca is the most similar to that of the sunflower, soy or peanut. It may be assumed that its similarity to the sunflower seed is the cause of the fact that the S. equestris willingly sucks the ripening achenes of the sunflower, too. (HORVATH, 1984).

In vitro cytotoxic activity of phenanthroindolizidine alkaloids from Cynanchum vincetoxicum and Tylophora tanakae against drug-sensitive and multidrug-resistant cancer cells.

Two known phenanthroindolizidine alkaloids, (-)-(R)-13aalpha-antofine (1) and (-)-(R)-13aalpha-6-O-desmethylantofine (2), and two new natural products, (-)-(R)-13aalpha-secoantofine (3) and (-)-(R)-13aalpha-6-O-desmethylsecoantofine (4), were isolated from Cynanchum vincetoxicum. The structures of all compounds were established by means of NMR methods including COSY, NOESY, HSQC, and HMBC experiments, supported by HRMS and optical rotation data. Cytotoxic activity of the isolated alkaloids, and of three other alkaloids previously isolated from Tylophora tanakae, (-)-(R)-13aalpha-tylophorine (5), (-)-(R)-13aalpha-7-O-desmethyltylophorine (6), and (+)-(S)-13abeta-isotylocrebrine (7), was assessed in vitro using a drug-sensitive KB-3-1 and a multidrug-resistant KB-V1 cancer cell line. Structure-activity relationships in this series of alkaloids are discussed. The IC(50) values of some of the alkaloids are in the low nanomolar range, being thus comparable to the activity of clinically used cytotoxic drugs. Previously reported adverse side effects of these alkaloids could possibly be overcome by modern tissue-specific drug targeting techniques.

Cytotoxic Activity of Some Phenanthroindolizidine N-Oxide Alkaloids from Cynanchum vincetoxicum

Two previously known phenanthroindolizidine alkaloids, (-)-10beta-antofine N-oxide (1) and (-)-10beta, 13aalpha-14beta-hydroxyantofine N-oxide (2), and a novel alkaloid, (-)-10beta,13aalpha-secoantofine N-oxide (3), were isolated from aerial parts of Cynanchum vincetoxicum. Their structures were established by means of NMR methods, including COSY, NOESY, HSQC, and HMBC experiments, as well as from their CD spectra. Cytotoxic activity of the alkaloids was assessed in vitro using both a drug-sensitive KB-3-1 and a multi-drug-resistant KB-V1 cancer cell line. The antofine derivatives (1 and 2) showed pronounced cytotoxicity against the drug-sensitive cell line (IC(50) values about 100 nM), whereas the secoantofine derivative (3) was considerably less active. The KB-V1 cell line showed a marginal resistance against all alkaloids, demonstrating that these compounds are poor substrates for the P-glycoprotein (P-170) efflux pump.

Effects of food plant and group size on predator defence: differences between two co‐occurring aposematic Lygaeinae bugs

Summary1. The role of food plant and aggregation on the defensive properties of two aposematic sympatrically occurring seed bugs, Tropidothorax leucopterus and Lygaeus equestris (Lygaeinae, Heteroptera), was investigated. Larvae reared on seeds either of their natural host plant Vincetoxicum hirundinaria (Asclepiadaceae) or of sunflower Helianthus annuus were subjected to predation by chicks.2. The two species differ in their dependency on the host for their defence. Lygaeus equestris was better defended on its natural host plant than on the alternative food, as indicated by fewer attacks, lower mortality, and predator avoidance after experience. No such effect of food plant could be found for T. leucopterus, suggesting the existence of alternative defences in this species.3. The number of attacks was lower when host plant‐fed larvae of both species were presented in groups.4. The discussion concerns how major components of an aposematic syndrome, such as host plant chemistry, insect colouration, and aggregation, are integrated with other life‐history traits to form alternative lifestyles in L. equestris and T. leucopterus.

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.

Acetophenones and new pregnane glycosides from the roots of Vincetoxicum hirundinaria

The roots of Vincetoxicum hirundinaria yielded the known pregnane glycosides cynatratoside E and cynatratoside C and three new pregane glycosides: hirundicoside B, hirundicoside C and hirundicoside D. Their structures have been elucidated by spectral data. Other isolated constituents: 2-hydroxyacetophenone, paenol, apocynine, 4-hydroxyacetophenone, 2,4-dihydroxyacetophenone, hancolupenone, sitosterol and syringic acid. 2-Hydroxyacetophenone was also identified as the major constituent of the essential oil by GC-MS.

Sequestration of plant compounds in a leaf beetle's defensive secretion: cardenolides in Chrysochus

Leaf beetles of the genus Chrysochus were shown to release secretions from pronotal and elytral glands when disturbed. This defensive reaction is similar to that observed in members of other, not closely related, subfamilies of the Chrysomelidae. In Chrysochus auratus and C. cobaltinus which both feed on plants of the genera Asclepias and Apocynum (Ascle piadaceae and Apocynaceae), the secretions contain cardenolides in a concentration of 77 to 358 μg/μl. Extracts of whole beetles contained cardenolides in concentrations too low for spectrophotometric quantification to a maximum of 748 μg/g dry weight. The cardenolides are apparently taken up from the food plant, since both plant genera contain these toxins and cardenolide pattern and concentration of whole beetle extracts and of the beetles' secretion depended on the local host plant. In C. asclepiadeus, which feeds on Vincetoxicum hirundinaria (Asclepiadaceae) devoid of cardenolides, phenylalanine, tryptophane, leucine and diacetyl putrescine were identified as major constituents of the secretions. The volume of secretion produced in the three Chrysochus species seems to be inversely correlated with the known toxicity of the compounds present in the secretion.

Population structure of a monophagous moth in a patchy landscape

1. The population structure of a monophagous noctuid moth, Abrostola asclepiadis, living on a patchily distributed perennial herb, Vincetoxicum hirundinaria is described. The study took place over 5 years at a landscape scale (about 12 km2).2. Patch occupancy rates and population densities were studied in relation to patch size, degree of patch isolation, level of sun exposure and distance from the coast. In addition, flight tests in the laboratory were performed to estimate the potential dispersal capacity of the moth.3. Occupancy rates were high and the likelihood of extinction depended on patch size. Small patches were less likely to be occupied than were large patches (> 10 m2). Sun‐exposed patches were occupied for a lower proportion of years than were shaded patches. No distance effects could be discerned at the spatial scale of study, presumably because the insect is a strong flier.4. Population densities in occupied patches decreased with increasing patch size. Furthermore, insect densities tended to increase with distance from the coast. Density changes in patches were synchronized.5. The studied insect population can be described as a ‘patchy population’sensu Harrison (1991) with spatially correlated population dynamics. These dynamics are superimposed on a landscape gradient.

Cover distributions of vascular plants in relation to soil chemistry and soil depth in a granite rock ecosystem

The variability in the cover distribution of vascular plants, accounted for by soil chemical properties and soil depth, on a granite slope with shallow autochtonous soil in southeast Sweden was evaluated using multivariate statistical regression and graphical methods. Soil acidity and soil depth were, to an often high degree, able to account for the variability in the distributions of the ca. 30 most frequent species, including Rumex acetosella, Vincetoxicum hirundinaria, Filipendula vulgaris, Satureja acinos, Geranium columbinum, Silene rupestris, and Arenaria serpyllifolia. The best expression of soil acidity was pH-KCl, though exchangeable Ca and Al were also important measures of the soil-plant relationships. The Ca:Al ratio was inferior in this respect. Also exchangeable or acid soluble phosphate was significantly related to the distribution of several species, whereas soil organic matter content was almost unrelated.

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.

Effects of pyrogallol on O-methylation of dopamine and salsolinol

In the cultured cells of Corydalis pallida var. tenuis, the formation of 6- O-methylated metabolites ( 6-D 4 and 6-D 7) from salsolinol-D 4 ( 2-D 4) was reduced by pyrogallol. The production of 3- O-methylated derivatives ( 10 and 10-D 3) from dopamine was almost not affected by pyrogallol. Similar results were obtained in intact plants, though the effect of pyrogallol on methylation of C-6-OH of salsolinol in plants is smaller than that in the cultured cells. These results show that the effects of pyrogallol on the methylation of C-6-OH of salsolinol and that on the methylation of C-3-OH of dopamine are different, suggesting that the O-methylating enzymes of salsolinol and dopamine are different in C. pallida var. tenuis. The production of 3- O-methyldopamine in the presence of pyrogallol was reduced in intact plants of Cynanchum vincetoxicum, but not in the cultured cells. The effect of pyrogallol on the methylation of salsolinol was uncertain in Cyn. vincetoxicum. Both 6- and 7- O-methylations of salsolinol occur in Cyn. vincetoxicum, while only 6- O-methylation occurs in C. pallida var. tenuis. This could reveal that the O-methylating enzymes at C-6 and C-7 are different.

Zur Symbiose von Cynanchum vincetoxicum (L.) Pers., Asclepias curassavica L. und Ceropegia woodii Schl. (Asclepiadaceae) mit Mycorrhiza-Pilzen (VAM)

Subterranean organs of Cynanchum vincetoxicum, Asclepias curassavica and Ceropegia woodii (Asclepiadaceae) were studied in respect to their symbiosis with VAM-fungi. Investigations revealed that both, cultivated plants and those from their natural habitat, were infected by these fungi. The structure of the endophyte, in these plants, is comparable with those in other flowering plants. The hyphae grow mainly in the intercellular space within the root cortex and also the vesicles are build intercellularly. Only the arbuscles are build intracellularly. Therefore, in the Gentianales the Asclepiadaceae do not demonstrate the same socalled structural incompatability as it was described for the Geniianaceae and Loganiaceae.

Alkaloids of Cynanchum vincetoxicum: efficacy against MDA-MB-231 mammary carcinoma cells.

Alkaloids 1-4 from Cynanchum vincetoxicum (asclepiadaceae) (Scheme 1) do not have affinity to the oestrogen receptor but they inhibit the growth of the hormone-independent mammary carcinoma cells MDA-MB-231 (Fig. 1) and bind to nucleosides and nucleotides (Table 1). Intercalation was not observed.

Population Dynamics of a Seed Feeding Bug, Lygaeus Equestris. 2. Temporal Dynamics

Population densities of the seed feeding bug, Lygaeus equestris have been followed for several years in three large study areas, each containing several host plant patches, in east central Sweden. Seed pod production of the perennial host plant Vincetoxicum hirundinaria as well as densities of another seed feeder, the tephritid fly Euphranta connexa, were also monitored. Densities of seed pods, E. connexa and L. equestris fluctuate about two orders of magnitude during a period of 11 yr. Population changes of L. equestris are density-independent during the non-breeding period of the year encompassing hibernation and preand posthibernation migrations. In most years mortality is low during this period, but occasionally high mortalities occur. During the breeding period, population changes are density-dependent and highly variable. Both sunshine conditions and abundance of seeds from the previous year affected population change during the breeding season. No competitive effect on L. equestris by E. connexa could be detected, despite the fact that E. connexa attacked over 90% of the pods in several years. Population density of L. equestris is determined by the sequence of weather effects of at least two years. The amount of sunshine, which affects the insect directly, also has indirect and delayed effects by affecting pod production of the host plant, and hence density of seeds on the ground in the following year. Furthermore, whereas population growth of L. equestris is positively affected by an increase in sunshine hours, pod production is negatively affected. This leads to considerable inertia in the temporal tracking of food resources by L. equestris.

Seed production and seed predation in a patchy and time-varying environment. Dynamics of a milkweed ? tephritid fly system

Vincetoxicum hirundinaria is a longlived perennial herb. Its pod production was measured during seven years in about 40 small isolated patches in two study areas in southeastern Sweden. Total pod production in the two areas varied synchronously and up to about 200 times between years. This variation was mainly due to drought conditions as determined by the interplay of weather (sunshine h) and site characteristics.Populations of a univoltine tephritid fly, euphranta connexa, whose larva feeds on V. hirundinaria seeds in the maturing pods, were monitored for five and seven years in the two study areas respectively. Larval fly populations in the two areas varied 30 and 50-fold between years, with highs in years when pods were abundant and lows when pods were scarce. The percentage of pods attacked by E. connexa, however, varied in the opposite direction, with very high attack rates (about 100%) when pods were scarce and low rates (down to 10-20%) when pods were common. Thus the temporal tracking of food resources by E. connexa was poor, resulting in yearly variations in the amount of unattacked pods (and seeds) being about 2,00-fold.Many host plant patches were small and totally without pods in some years, causing frequent local extinctions of E. connexa. Patches were, however, readily colonized in later years when pods appeared again. Low overall attack rates in certain years were thus only to a minor extent explainable by host plant patches being uncolonized by the fly. The efficient spatial tracking of resources by the fly population allows this population system to be analyzed largely in terms of its temporal dynamics.Although E. connexa populations often exploit only a minor part of their potential larval resources, the rate of population change was closely correlated with these resources expressed on a per capita basis. Natural enemies only have negligible effects on E. connexa population trends. In this population system the herbivore (seed predator) population is thus controlled by its food resources, but weather-imposed temporal variations in resource set are too large for the herbivore population to closely track its resource base. This temporal tracking inertia has important implications for the long-term production of healthy seeds.

Ultrastructural Observations on the Dikaryotic Haustorium ofCronartium Flaccidum(Alb. & Schw.) Wint. inVincetoxicum HirundinariaMedicus

SUMMARYThe haustorium of the uredial stage of Cronartium flaccidum in Vincetoxicum hirundinaria was studied with TEM. The observations concern the haustorial mother cell and its relation to the host cell wall, the penetration peg, the shape and the cytoplasm of the haustorium and some host cell organelles in relation to the haustorium. The presence of collars was noted. These features are similar to those described for host-dikaryotic haustorium relationship in other rusts. The extrahaustorial matrix however shows a unusual development. In fact, it wraps the whole length of haustorial neck although it is separated from the haustorial neck wall by the extrahaustorial membrane doubled in this region. The probable significance of this host-parasite interface, perhaps limited to the genus Cronartium, is discussed.

THE NECTARIES OF CYNANCHUM VINCETOXICUM (ASCLEPIADACEAE)

ABSTRACT The nectary epithelia of Cynanchum vincetoxicum cover cavities formed between the base of the corolla and the gynostegium, and they are in open contact with the stigmatic chambers. In addition to sugars, insoluble substances are secreted, presumably mainly lipidie in nature. The wall of epithelial cells at the apical dome is traversed by channellike structures. The mitochondria are partly aggregated into large complexes. Golgi apparatus and ER are well developed and may participate in the secretory process, although unequivocal evidence is lacking.

Vergleichende Untersuchungen zum Elementgehalt von Bodenpflanzen auf Gipsstandorten

Summary On the xerothermic gypsum sites of Thuringia the concentrations of elements in the leaves of 13 characteristic species of the ground vegetation were determined. As far as possible the same species on carbonate and silicate sites served for the purpose of comparison. The grass species possess predominantly lower N, P, Ca, Mg, SO 4 —S, Zn and Cu values in their leaves than herbs. Cynanchum vincetoxicum, Salvia pratensis, Gypsophila fastigiata and Euphorbia cyparissias form a group of species with mostly higher concentrations of nutrient elements. On the gypsum sites the N content in leaves is mostly higher, while in the majority of the cases the Fe and Al content is lower than on the comparison sites. The Ca concentration in leaves decreases beginning from the gypsum sites via the carbonate to the silicate ones. On the gypsum and carbonate sites the K, P and Mn values are lower than on the silicate ones. With the exception of the often increased Ca content in the leaves ground vegetation growing on xerothermic gypsum and carbonate sites has in the main lower element contents as compared with vegetation growing on gneiss sites.

Laboratory Studies on the Feeding Preference and Feeding Behaviour in Lygaeus equestris (L.) (Het. Lygaeidae)1

AbstractThe seed-feeding bug Lygaeus equestris changes and extends its food plant spectrum during its life-cycle. Whether this is the result of only the natural succession of the food plants, or also includes a change in the insect's food preference during its life, was the primary question of the present paper. Feeding-choice tests using ripe seeds from important food plants in the laboratory showed that Cynanchum vincetoxicum seeds were preferred during all stages of life. Among the lesser preferred seeds tested, a shift in preference occurred during the bug's development. It seems probable that this shift may be due as much to the physical as to the chemical properties of the seeds. It is suggested that most of the other plant species exploited for feeding by L. equestris probably serve mainly as substitute food when suitable developmental stages of C. vincetoxicum are absent or in short supply. Furthermore the paper gives some notes on duration of feeding upon seeds and effects of seed coat at initiation of feeding on Cynanchum and Helianthus seeds. During the third larval instar, the preference switches from the endosperm to the seed coat for initiation of feeding on Cynanchum seeds, and so it remains during the following stages. On Helianthus seeds, only adult L. equestris feed as willingly through the coat as directly from the endosperm.