| strawberry crinkle virus, a cytorhabdovirus needing more attention from virologists. | summary taxonomic relationship: a member of nonsegmented, negative-sense, single-stranded rna viruses of the genus cytorhabdovirus (type member: lettuce necrotic yellows virus), family rhabdoviridae, order mononegavirales. members of the family rhabdoviridae can infect vertebrates, invertebrates and plants. physical properties: virions are bacilliform, 74-88 nm in diameter and 163-383 nm in length with surface projections probably composed of trimers of the glycoprotein g, occurring in the cytop ... | 2000 | 20572980 |
| interspecific symbiont transfection confers a novel ecological trait to the recipient insect. | in japan, pea aphids acyrthosiphon pisum mainly feed on vetch and clover, and many aphid clones produce more progeny on vetch than on clover. in this context, particular genotypes of the facultative symbiont regiella insecticola enhance reproduction of infected pea aphids specifically on clover, thereby broadening the suitable food plant range of the insect. a species that is sympatric to a. pisum, vetch aphids megoura crassicauda, are commonly found on vetch but not on clover. laboratory rearin ... | 2010 | 20880856 |
| comparative analyses of salivary proteins from three aphid species. | saliva is a critical biochemical interface between aphids and their host plants; however, the biochemical nature and physiological functions of aphid saliva proteins are not fully elucidated. in this study we used a multidisciplinary proteomics approach combining liquid chromatography-electrospray ionization tandem mass spectrometry and two-dimensional differential in-gel electrophoresis/matrix-assisted laser desorption/ionization time-of-flight/mass spectrometry to compare the salivary proteins ... | 2014 | 24382153 |
| [effect of sinigrin on sucrose uptake by some polyphagous and oligophagous aphids (aphididae)]. | the effect of 0.1% sinigrin on sucrose uptake (20% aqueous solution) by some polyphagous and oligophagous aphid species was tested using the tracer method. in the presence of sinigrin the sucrose ingestion of brevicoryne brassicae, myzus persicae and megoura viciae was promoted. with rhopalosiphum padi there was a strong, and with aphis fabae and acyrthosiphon pisum only a slight inhibition of sucrose uptake. aulacorthum circumflexum reacted positively in some experiments, but negatively in othe ... | 1972 | 28313041 |
| plant cues for aphid navigation in vascular tissues. | the ability of aphids to detect and find sieve tubes suggests that aphids receive cues for sieve-tube recognition by taking samples. specific natural conditions such as ph value, sugar species and concentration, viscosity, and oxygen pressure may enable sieve-tube detection. we tested the preference of megoura viciae and myzus persicae for potential plant-borne orientation parameters in artificial choice-chamber systems. both species preferred sucrose (in comparison with fructose, glucose, raffi ... | 2010 | 21075945 |
| a positive trait-mediated indirect effect involving the natural enemies of competing herbivores. | trait-mediated indirect effects can have important effects on food web dynamics but are still poorly understood in the field. in a previous population cage study of a small community of aphids and an aphid natural enemy it was found that a trait-mediated indirect effect involving the natural enemy's behaviour was key to understanding community persistence. here evidence is presented that a related phenomenon involving some of the same species occurs in the field. surveys showed that two species ... | 2009 | 19214584 |
| crystal structures and binding dynamics of odorant-binding protein 3 from two aphid species megoura viciae and nasonovia ribisnigri. | aphids use chemical cues to locate hosts and find mates. the vetch aphid megoura viciae feeds exclusively on the fabaceae, whereas the currant-lettuce aphid nasonovia ribisnigri alternates hosts between the grossulariaceae and asteraceae. both species use alarm pheromones to warn of dangers. for n. ribisnigri this pheromone is a single component (e)-β-farnesene but m. viciae uses a mixture of (e)-β-farnesene, (-)-α-pinene, β-pinene, and limonene. odorant-binding proteins (obp) are believed to ca ... | 2016 | 27102935 |
| presence of a functional (ttagg)(n) telomere-telomerase system in aphids. | the structure of the telomeres of four aphid species (acyrthosiphon pisum, megoura viciae, myzus persicae and rhopalosiphum padi) was evaluated by southern blotting and fluorescent in situ hybridization, revealing that each chromosomal end consists of a (ttagg)(n) repeat. the presence of a telomerase coding gene has been verified successively in the a. pisum genome, revealing that aphid telomerase shares sequence identity ranging from 12% to 18% with invertebrate and vertebrate homologues, and p ... | 2011 | 21667174 |
| mechanisms for stable coexistence in an insect community. | in this paper, we formulate a three-species ecological community model consisting of two aphid species (acyrthosiphon pisum and megoura viciae) and a specialist parasitoid (aphidius ervi) that attacks only one of the aphids (a pisum). the model incorporates both density-mediated and trait-mediated host-parasitoid interactions. our analysis shows that the model possesses much richer and more realistic dynamics than earlier models. our theoretical results reveal a new mechanism for stable coexiste ... | 2010 | 20578788 |
| antibiotics, primary symbionts and wing polyphenism in three aphid species. | the possible role of the primary buchnera symbionts in wing polyphenism is examined in three aphid species. presumptive winged aphids were fed on antibiotic-treated beans to destroy these symbionts. as previously reported, this leads to inhibited growth and low/zero fecundity. when such treatment is applied to the short-day-induced gynoparae (the winged autumn migrant) of the black bean aphid, aphis fabae, it also causes many insects to develop as wingless or winged/wingless intermediate adult f ... | 2007 | 17628287 |
| occurrence of nitric oxide synthase in megoura viciae buckton (homoptera, aphididae): an histochemical and immunohistochemical localisation. | nitric oxide (no) is known to be involved in many physiological reactions of insects. we analysed nos localisation in aphids of the species megoura viciae by means of histochemical reaction for the nadph-diaphorase activity and immunohistochemical methods for unos, nnos and inos. the obtained data provided a complex and peculiar pattern of nos distribution in cells and tissue of m. viciae. the histochemical reaction for nadph-diaphorase was an indicative, but not exact marker of nos localisation ... | 2005 | 16377581 |
| the putative brain photoperiodic photoreceptors in the vetch aphid, megoura viciae. | in an attempt to identify the brain photoreceptors that mediate the photoperiodic response of the vetch aphid, megoura viciae, we utilised immunocytochemical techniques and employed 20 antibodies directed against invertebrate and vertebrate opsins and phototransduction proteins. a sub-set of these antibodies (to drosophila rhodopsin 1: rh1-1; vertebrate cone opsins: cos-1; cern-874; cern-933; vertebrate rod opsin: cern-901; vertebrate arrestin: ab-arr; vertebrate transducin+arrestin+rhodopsin ki ... | 1999 | 12770276 |
| the neurosecretory system in the aphid megoura viciae, with reference to unusual features associated with long distance transport of neurosecretion. | | 1977 | 67062 |
| corpus allatum activity and wing determination in megoura viciae. | | 1975 | 1207750 |
| sex pheromone in the aphid megoura viciae. | | 1972 | 18663846 |
| thymidine h3 incorporation in the nurse cells of amphigonic and parthenogenetic ovaries of megoura viciae (hom. aph.). | | 1966 | 5971926 |
| the organization of flight muscle in an aphid, megoura viciae (homoptera). with a discussion on the structure of synchronous and asynchronous striated muscle fibers. | the organization of the indirect flight muscle of an aphid (hemiptera-homoptera) is described. the fibers of this muscle contain an extensive though irregularly disposed complement of t system tubules, derived as open invaginations from the cell surface and from the plasma membrane sheaths accompanying the tracheoles within the fiber. the sarcoplasmic reticulum is reduced to small vesicles applied to the t system surfaces, the intermembrane gap being traversed by blocks of electron-opaque materi ... | 1965 | 5328055 |
| the location of the photoperiodic receptors in the aphid megoura viciae buckton. | | 1964 | 14161603 |
| analysis of insect holocentric chromosomes by atomic force microscopy. | in order to go in depth into the analysis of holocentric chromosome structure, atomic force microscopy (afm) was applied to metaphase plates of the aphid megoura viciae. afm showed that aphid chromatids adhere to one another without any prominent structure detectable between them and without any evidence of chromosomal constrictions. afm thus provided new and reliable evidences at a nanomolecular level concerning the holocentric structure of aphid chromosomes, without any of the artefacts due to ... | 2003 | 12921164 |
| responses of the aphids phorodon humuli and rhopalosiphum padi to sex pheromone stereochemistry in the field. | gynoparous female and male damson-hop aphids, phorodon humuli (schrank), were caught in the field by water traps that were releasing the sex pheromone of this species, (1rs,4ar,7s,7as)-nepetalactol. no behavioral activity was elicited by (4as,7s,7ar)-nepetalactone, the major sex pheromone component of other aphid species such as megoura viciae buckton, even though olfactory cells were found in the secondary rhinaria on the third antennal segment of p. humuli that responded strongly to this compo ... | 2003 | 14682508 |
| os-d-like genes and their expression in aphids (hemiptera: aphididae). | it has been proposed that a family of small soluble binding proteins, variously named as chemosensory proteins, sensory appendage proteins, pherokines and os-d-like proteins, are involved in insect chemoreception. these proteins are present in a wide range of insect species and have a characteristic four cysteine motif. we have cloned cdnas and gene sequences encoding these proteins from a number of aphid species, the first report of such in the order hemiptera and supporting the view that these ... | 2005 | 16033435 |
| smells like aphids: orchid flowers mimic aphid alarm pheromones to attract hoverflies for pollination. | most insects are dependent on chemical communication for activities such as mate finding or host location. several plants, and especially orchids, mimic insect semiochemicals to attract insects for unrewarded pollination. here, we present a new case of pheromone mimicry found in the terrestrial orchid epipactis veratrifolia. flowers are visited and pollinated by several species of aphidophagous hoverflies, the females of which also often lay eggs in the flowers. the oviposition behaviour of thes ... | 2011 | 20943694 |
| artificial nighttime light changes aphid-parasitoid population dynamics. | artificial light at night (alan) is recognized as a widespread and increasingly important anthropogenic environmental pressure on wild species and their interactions. understanding of how these impacts translate into changes in population dynamics of communities with multiple trophic levels is, however, severely lacking. in an outdoor mesocosm experiment we tested the effect of alan on the population dynamics of a plant-aphid-parasitoid community with one plant species, three aphid species and t ... | 2015 | 26472251 |
| the design, synthesis, and evaluation of 1,5,7-trisubstituted-3-pyridyl-xanthones for use as insecticides starting from pyripyropene a. | a readily accessible template of 1,5,7-trisubstituted-3-pyridyl-xanthones was designed starting from naturally occurring pyripyropene a for agrichemical development. our originally developed ag2 co3 -mediated oxidative cyclization enabled ready access to the key scaffold, 1,5,7-trihydroxy-3-chloro-xanthone. the chemo- and regioselective sequential introduction of four substituents to the scaffold rapidly afforded the desired, structurally diverse 1,5,7-trisubstituted-3-pyridyl-xanthones. an eval ... | 2016 | 27862416 |
| differential regulations of wing and ovarian development and heterochronic changes of embryogenesis between morphs in wing polyphenism of the vetch aphid. | in wing polyphenisms that produced alternative wing morphs depending on environmental conditions, the developmental regulations to balance between flight and reproductive abilities should be important. many species of aphids exhibit wing polyphenisms, and the development of wing and flight muscles is thought to incur costs of reproductive ability. to evaluate the relationship between flight and reproduction, the fecundity and the wing- and ovarian development in the parthenogenetic generations w ... | 2015 | 19878289 |
| screening of upregulated genes induced by high density in the vetch aphid megoura crassicauda. | aphids exhibit several polyphenisms in which discontinuous, alternative phenotypes are produced depending on environmental conditions. one representative example is the wing polyphenism, where winged and wingless females are produced through parthenogenesis. previous work has shown that, in some aphid species, the density condition sensed by the mother aphid determines the developmental fate of embryos in her ovary, with high densities leading to winged progeny and low densities to wingless prog ... | 2012 | 22514053 |
| juvenile hormone titer and wing-morph differentiation in the vetch aphid megoura crassicauda. | most aphids exhibit wing polyphenism, in which winged and wingless females are produced depending on aphid densities. although juvenile hormone (jh) has been implicated in the regulation of aphid wing polyphenism, relatively few studies examining the direct relationship between jh titer and resultant wing morphs have been undertaken. we therefore investigated the relationship between jh iii titer and the development of wing morphs in the vetch aphid megoura crassicauda during postembryonic devel ... | 2013 | 23434762 |
| allatostatin-like and akh/hrth-like peptides in the aphid megoura viciae. | knowledge of the structures of neuropeptides that regulate development, metabolism, and behaviour in insects is extensive, but nothing is known of the identity of regulatory peptides in the aphid neuroendocrine system. the present study applies a radioimmunoassay to reveal the existence of at least two allatostatin-like peptides in the aphid, megoura viciae. immunocytochemistry using antibodies recognising cockroach and dipteran allatostatins (dip-ast-7 and cav-ast-1) revealed the presence of al ... | 2000 | 10764547 |
| two opsin genes from the vetch aphid, megoura viciae. | the cdnas of two opsins (megopsin1 and megopsin2) from the vetch aphid, megoura viciae, have been sequenced and encoded for gene products with 378 and 371 amino acid residues, respectively. phylogenetic analysis reveals that megopsin1 falls into the insect long-wavelength opsin group and megopsin2 is a member of the insect uv-wavelength opsins. both opsins share the key features of g-protein-coupled receptors and the specific motifs of photopigments. in situ hybridization demonstrated that the t ... | 2000 | 10762427 |
| [the suitability of megoura viciae(buckt.) (aphid.) for larvae and adult females of aphelinus asychis walker (aphelin.)]. | in the laboratory, the females of the polyphagous aphid parasite aphelinus asychis accepted vetch aphids (megoura viciae on vicia faba) for oviposition and host feeding as readily as peach aphids (myzus persicae on brassica oleracea var. gongylodes) of the same size. however, the vetch aphids defended themselves less often; consequently, they were parasitized more frequently.with very few exceptions, all parasite larvae in the vetch aphids died after some days. blood reactions were scarcely noti ... | 1974 | 28308698 |
| an aphid's odyssey--the cortical quest for the vascular bundle. | sensing ph and sucrose concentration (with a preference for ph values of 7.0-7.5 and sucrose concentrations of approximately 400 mmol l(-1)) enables aphids to recognise sieve tubes inside vascular bundles. however, it is still unclear how aphids find their way to the vascular bundles. membrane potentials in the cortex of vicia faba stems were measured along a radial transect from the epidermis to the sieve elements and there was no gradient detected that could be used by aphids to guide their st ... | 2011 | 22031752 |
| the influence of natural enemies on wing induction in aphis fabae and megoura viciae (hemiptera: aphididae). | previous studies have shown that the aphid species, aphis fabae scopoli and megoura viciae buckton, do not produce winged offspring in the presence of natural enemies, in contrast to results for the pea aphid (acyrthosiphon pisum (harris)) and the cotton aphid (aphis gossypii glover); but these studies did not involve exposing aphids directly to natural enemies. we exposed colonies of both a. fabae and m. viciae to foraging lacewing (chrysoperla carnea (stephens)) larvae and found that the preda ... | 2008 | 18076776 |
| resource competition and shared natural enemies in experimental insect communities. | much theory has been developed to explore how competition for shared resources (exploitation competition) or the presence of shared natural enemies (apparent competition) might structure insect and other communities. it is harder to predict what happens when both processes operate simultaneously. we describe an experiment that attempted to explore how shared natural enemies and resource competition structured a simple experimental insect community. replicated communities were assembled in popula ... | 2009 | 19082628 |
| nor heteromorphism within a parthenogenetic lineage of the aphid megoura viciae. | in parthenogenetic females of a clone of the aphid megoura viciae (homoptera, aphididae), more than 50% of the cells show heteromorphism between homologous nors which are located on one telomeric region of the two x chromosomes. using different techniques, such as staining with the cg-specific fluorochrome chromomycin a3, silver staining and in-situ hybridization with an rdna probe, we have shown that the observed heteromorphism is due to an unequal distribution of ribosomal genes between homolo ... | 1999 | 10328627 |
| a double circadian oscillator model for quantitative photoperiodic time measurement in insects and mites | from studies on photoperiodic time measurement in insects it is known that different night lengths at the same side of the critical night length can have different inductive strengths. this means that nights of different length, and either longer or shorter than the critical night length, can have qualitatively different values. nevertheless, few photoperiodic-clock models have been developed that are based on quantitative night-length measurement. in this paper a model is proposed that consists ... | 1998 | 9778441 |
| chromosomal localization of a highly repeated ecori dna fragment in megoura viciae (homoptera, aphididae) by nick translation and fluorescence in situ hybridization. | to investigate the genome of the aphid megoura viciae at molecular level, we have studied total dna by agarose gel electrophoresis after cleavage with different restriction endonucleases. ecori digestion produced a highly repeated dna fragment, about 600 pb long. the contribution of this ecori element to the total genome of m. viciae was estimated at about 6% by means of densitometric scanning of agarose gel photographs. the chromosomal localization of this fragment, investigated by fluorescent ... | 1996 | 8871828 |
| an electron microscopic study of flight muscle breakdown in an aphid megoura viciae. | within two days of settling to feed on a host plant degenerative changes can be detected in the flight muscles of aphids at the ultrastructural level. the thick myosin filaments and the m lines and later the z bands disappear leaving the thin actin filaments in the cytoplasm. the mitochondria change their configuration and become enveloped in cytosegresomes. as mitochondria become reduced in number the numbers of lysosomes and residual bodies in the cells build up. the cells then appear to becom ... | 1980 | 7192019 |
| some functions of identified neurosecretory cells in the brain of the aphid, megoura viciae. | | 1978 | 631542 |
| the role of neurosecretion in the photoperiodic control of polymorphism in the aphid megoura viciae. | the location of the photoperiodic mechanism controlling the production of the sexual and parthenogenetic morphs by apterous parents was examined by selectively injuring the brain with an r.f. microcautery. lesions destroying the group i neurosecretory cells (nsc) in the protocerebrum abolished the response to changed daylength. extensive damage to other nsc groups, to the compound eyes and optic lobes was without effect. it is concluded that the group i nsc are the effectors, secreting a virgino ... | 1977 | 894176 |
| heterochromatin heterogeneity in the holocentric x chromatin of megoura viciae (homoptera, aphididae). | holocentric chromosomes, prepared by spreading embryo cells obtained from megoura viciae parthenogenetic females, have been c-banded, enzymatically digested in situ using the specific endonucleases ddei (c↓tnag), drai (ttt↓aaa), tru9i (tt↓aa), and cfoi (gcg↓c), and subsequently stained with giemsa, dapi, cma3, and agno3. we observed that the x chromosome had the best defined banding patterns. in the m. viciae x chromosome there is a certain amount of heterogeneity in heteroch ... | 1996 | 18469907 |
| cytological and electrophoretic analysis of dna methylation in the holocentric chromosomes of megoura viciae (homoptera, aphididae). | chromosomal and purified dna methylation patterns were determined in the holocentric chromosomes of megoura viciae by treatment with mspi and hpaii. both enzymes produced a clear c-like banding pattern but widely digested one telomere of the x chromosome, which appeared as heterochromatic after c-banding treatment and brightly fluorescent after chromomycin a3 staining. quantitative microfluorometric evaluations of dna extraction performed on cytological preparations showed that both isoschizomer ... | 1994 | 18470107 |
| ultrastructural features of egg development in oviparae of the vetch aphid, megoura viciae buckton. | in the ovaries of the oviparous morph of the aphid, megoura viciae, resting oocytes are located in the basal region of each germarium. during previtellogenic egg development, electron-dense spheres appear in the ooplasm. during vitellogenesis a brush border develops at the oolemma, and numerous protein and lipid-like spheres accumulate in the egg cytoplasm. follicle cells are of two morphologically distinct types, termed 'type 1' and 'type 2' follicle cells. unlike the more numerous 'type 1' cel ... | 1990 | 18620293 |
| the effect of temperature on the photoperiodic 'clock' and 'counter' of a scottish clone of the vetch aphid, megoura viciae. | photoperiodic response curves were determined for a scottish clone of the vetch aphid, megoura viciae buckton, at three temperatures: 12.5, 15, and 17.5 degrees c. critical night lengths (cnls) for ovipara (sexual female) induction were 6 h, 7 h and 8 h, respectively. high incidences of ovipara production were observed in all night lengths longer than the cnl including continuous darkness (dd), as well as in continuous light (ll) at 12.5 and 15 degrees c. at the same three temperatures, the numb ... | 2000 | 10742521 |
| aphid watery saliva counteracts sieve-tube occlusion: a universal phenomenon? | ca2+-binding proteins in the watery saliva of megoura viciae counteract ca2+-dependent occlusion of sieve plates in vicia faba and so prevent the shut-down of food supply in response to stylet penetration. the question arises whether this interaction between aphid saliva and sieve-element proteins is a universal phenomenon as inferred by the coincidence between sieve-tube occlusion and salivation. for this purpose, leaf tips were burnt in a number of plant species from four different families to ... | 2009 | 19801435 |
| effects of urbanization on direct and indirect interactions in a tri-trophic system. | while effects of urbanization on species assemblages are receiving increasing attention, effects on ecological interactions remain largely unexplored. we investigated how urbanization influences the strength of direct and indirect trophic interactions in a tri- trophic system. in a field experiment including five cities and nearby farmed areas, we used potted vicia faba plants and manipulated the presence of megoura viciae aphids and that of naturally occurring aphid predators. when predators co ... | 2016 | 27411241 |