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Paul M. Brakefield - One of the best experts on this subject based on the ideXlab platform.

  • Releases of a natural flightless strain of the ladybird beetle Adalia bipunctata reduce aphid-born honeydew beneath urban lime trees
    BioControl, 2012
    Co-Authors: S.t.e. Lommen, Peter W. De Jong, Thomas C. Holness, Alfons J. Van Kuik, Paul M. Brakefield
    Abstract:

    Aphids can cause major environmental problems in urban areas. One important problem is the annual outbreaks of lime aphid, Eucallipterus tiliae (L.) (Hemiptera: Aphididae), which spoil the surroundings of lime trees by depositing honeydew. To date no environmentally friendly method has been demonstrated to yield effective control of lime aphids. Attempts are made in some cities to control lime aphids by releasing larvae of the native two-spot ladybird beetle, Adalia bipunctata (L.) (Coleoptera: Coccinellidae). However, it is known that adult ladybird beetles disperse soon after release, and there is little indication they provide control of the aphids. Here, we demonstrate experimentally that releases of a flightless strain of A. bipunctata, obtained from natural variation in wing length, can reduce the impact of honeydew from lime aphid outbreaks on two species of lime in an urban environment. Both larvae and adult beetles were released, and we discuss the contribution of the flightless adults to the decline in honeydew.

  • Genetic linkage between melanism and winglessness in the ladybird beetle Adalia bipunctata.
    Genetica, 2012
    Co-Authors: Suzanne T E Lommen, Peter W. De Jong, Kees G Koops, Paul M. Brakefield
    Abstract:

    We report a case of genetic linkage between the two major loci underlying different wing traits in the two-spot ladybird beetle, Adalia bipunctata (L.) (Coleoptera: Coccinellidae): melanism and winglessness. The loci are estimated to be 38.8 cM apart on one of the nine autosomes. This linkage is likely to facilitate the unravelling of the genetics of these traits. These traits are of interest in the context of the evolution of intraspecific morphological diversity, and for the application of ladybird beetles in biological control programs.

  • Development of a wingless morph in the ladybird beetle, Adalia bipunctata.
    Evolution & Development, 2009
    Co-Authors: S.t.e. Lommen, Suzanne V. Saenko, Yoshinori Tomoyasu, Paul M. Brakefield
    Abstract:

    Many taxa of winged insects have independently lost the ability to fly and often possess reduced wings. Species exhibiting natural variation in wing morphology provide opportunities to investigate the genetics and developmental processes underlying the evolution of alternative wing morphs. Although many wing dimorphic species of beetles are known, the underlying mechanisms of variation are not well understood in this insect order. Here, we examine wing development of wild type and natural wingless morphs of the two-spot ladybird beetle, Adalia bipunctata. We show that both pairs of wings are distally truncated in the wingless adults. A laboratory population of the wingless morph displays heritable variation in the degree of wing truncation, reflecting reduced growth of the larval wing discs. The coexistence of variable wingless morphs supports the idea that typical monomorphic wingless insects may be the result of a gradual evolution of wing loss. Gene expression patterns in wing discs suggest that the conserved gene network controlling wing development in wild-type Adalia is disrupted in the dorsoventral patterning pathway in the wingless morphs. Previous research on several species of ant has revealed that the anteroposterior wing patterning pathway is disrupted in wingless workers. Future investigations should confirm whether interruptions in both taxa are limited to the patterning pathways found thus far, or whether there are also shared interruption points. Nevertheless, our results highlight that diverse mechanisms of development are likely to underlie the evolution of wingless insects.

  • Phenotypic plasticity of elytron length in wingless two-spot ladybird beetles, Adalia bipunctata (Coleoptera: Coccinellidae)
    European Journal of Entomology, 2005
    Co-Authors: S.t.e. Lommen, Peter W. De Jong, Paul M. Brakefield
    Abstract:

    Winglessness in the two-spot ladybird beetle Adalia bipunctata (L.) is determined by a single locus with the wingless allele recessive to the winged wildtype allele. The expression of the wingless trait is highly variable, with individuals missing a vari- able part of elytra and flight wings; the elytra and wings appear to be truncated rather than miniature in form. The degree of wing- lessness is partly determined genetically. Here we report on the phenotypic plasticity of the degree of winglessness. The environmental effect on elytron length relative to maximal elytron length in wingless phenotypes was studied by rearing offspring of single pair crosses of this form at a low (19°C) or high (29°C) temperature. Offspring reared at 19°C showed relatively longer elytra than those reared at 29°C.

  • Genetic basis and fitness consequences of winglessness in the two-spot ladybird beetle, Adalia bipunctata.
    Heredity, 2004
    Co-Authors: H Ueno, P. W. De Jong, Paul M. Brakefield
    Abstract:

    The genetic basis and fitness consequences of winglessness were investigated in the two-spot ladybird beetle, Adalia bipunctata. By breeding lines from a wingless individual found at The Uithof, Utrecht in The Netherlands, the wingless condition was confirmed to be under the control of a major allele, recessive to the wild type. Wingless individuals, on average, had a longer developmental period, a lower egg production and a shorter lifespan than the wild type with wings, suggesting that the expression of the wingless allele has functionally interrelated gene actions involving a wide range of fitness components. While the wingless allele influences various traits, significant among-family variation in the degree of winglessness suggests that its phenotypic expression is also dependent on the genetic background and modifier loci. Furthermore, there was a consistent pattern of correlation between the degree of winglessness and life history traits; the most extreme wingless individuals showed the lowest fitness while those with more fully developed wings tended to have the highest fitness. This correlation suggests that the modifier genes influence both wing formation and fitness components. The significance of such epistatic effects to the evolution of flightlessness in insects is discussed.

Gregory D D Hurst - One of the best experts on this subject based on the ideXlab platform.

  • No evidence that presence of sexually transmitted infection selects for reduced mating rate in the two spot ladybird, Adalia bipunctata
    PeerJ, 2015
    Co-Authors: Sophie L. Jones, Daria Pastok, Gregory D D Hurst
    Abstract:

    Sexually transmitted infections (STIs) are common in animals and plants, and frequently impair individual fertility. Theory predicts that natural selection will favour behaviours that reduce the chance of acquiring a STI. We investigated whether an STI, Coccipolipus hippodamiae has selected for increased rejection of mating by female Adalia bipunctata as a mechanism to avoid exposure. We first demonstrated that rejection of mating by females did indeed reduce the chance of acquiring the mite. We then examined whether rejection rate and mating rate differed between ladybirds from mite-present and mite-absent populations when tested in a common environment. No differences in rejection intensity or remating propensity were observed between the two populations. We therefore conclude there is no evidence that STIs have driven the evolution of female mating behaviour in this species.

  • Spatial variation in the incidence of a sexually transmitted parasite of the ladybird beetle Adalia bipunctata (Coleoptera: Coccinellidae)
    European Journal of Entomology, 2006
    Co-Authors: K. Mary Webberley, John J. Sloggett, Michael E. N. Majerus, Matthew C. Tinsley, Gregory D D Hurst
    Abstract:

    Whilst sexually transmitted pathogens and parasites are common on insects and other animals, the factors affecting their incidence are currently uncertain. In order to understand the factors important in determining the presence of sexually transmitted parasites, it would be helpful to have information on intraspecific variation in incidence, as the causes of this variation are likely to reflect the likely causes of the presence/absence of sexually transmitted parasites across species. We therefore mapped the incidence of the parasite Coccipolipus hippodamiae within Europe on its primary host, the ladybird Adalia bipunctata. We observed that C. hippodamiae was present widely in Central, Southern and Eastern Europe, but was absent from northerly and north-western popula- tions. The cause of this pattern of incidence variation is discussed, with particular reference to the voltinism of the host. We also note that the distribution of C. hippodamiae on A. bipunctata is not congruent with that of another sexually transmitted parasite of this species, Hesperomyces virescens.

  • Invasion of one insect species, Adalia bipunctata, by two different male-killing bacteria
    Insect Molecular Biology, 1999
    Co-Authors: Gregory D D Hurst, Ilia A. Zakharov, Tamsin M. O. Majerus, J. H. Graf Von Der Schulenburg, Dominique Bertrand, J. Baungaard, Wolfgang Völkl, Richard Stouthamer, M. E. N. Majerus
    Abstract:

    Male-killing bacteria, which are inherited through the female line and kill male progeny only, are known from five different orders of insect. Our knowledge of the incidence of these elements has stemmed from discovery of their phenotype in different species. Our estimate of the frequency with which insects have been invaded by these elements therefore depends on each observation of the male-killing phenotype within a species being associated with a single micro-organism. We here record an example of a single insect species being infected with two taxonomically distinct male-killing bacteria. Western European populations of the two-spot ladybird, Adalia bipunctata, have previously been shown to bear a male-killing Rickettsia. However, we here show that the majority of the male-killing lines tested from Central and Eastern Europe do not bear this bacterium. Rather, 16S rDNA sequence analysis suggests male-killing is associated with a member of the genus Spiroplasma. We discuss this conclusion in relation to the evolutionary genetics of male-killing bacteria, and the evolution of male-killing behaviour in the eubacteria.

  • Sexually transmitted disease in a promiscuous insect, Adalia bipunctata
    Ecological Entomology, 1995
    Co-Authors: Gregory D D Hurst, Linda E. Walker, Ilia A. Zakharov, Rosie G. Sharpe, Angela H. Broomfield, Tamsin M. O. Majerus, Michael E. N. Majerus
    Abstract:

    Abstract. 1Sexually transmitted diseases (STDs) have rarely been reported in insects and other invertebrates. The majority of those reported involve organisms where sexual transmission is augmented by either vertical (i.e. inherited) transmission, or horizontal transmission, independent of host sexual activity. 2We here demonstrate the existence of an STD in the coccinellid beetle Adalia bipunctata. This species bears a parasitic mite of the genus Coccipolipus. We show that, like many other podapolipid mites, this mite is transmitted between host individuals at a high rate during copulation. It also appears to be transmitted at a low rate between non-copulating individuals. 3We show that infected female A.bipunctata produced eggs at a reduced rate, and that the eggs produced by infected females have highly decreased viability. However, no effect of infection upon host longevity was observed. 4The results are discussed in relation to the incidences of sexually transmitted disease in invertebrates in general, the causes of disease symptoms, and the importance of this disease in the evolution of A.bipunctata.

  • The effect of infection with male-killing Rickettsia on the demography of female Adalia bipunctata L. (two spot ladybird)
    Heredity, 1994
    Co-Authors: Gregory D D Hurst, Emma L Purvis, John J. Sloggett, Michael E. N. Majerus
    Abstract:

    The effect of infection with male-killing Rickettsia on the demography of female Adalia bipunctata L. (two spot ladybird)

Michael E. N. Majerus - One of the best experts on this subject based on the ideXlab platform.

  • Female multiple mating in wild and laboratory populations of the two-spot ladybird, Adalia bipunctata
    Molecular Ecology, 2008
    Co-Authors: Penelope R. Haddrill, Michael E. N. Majerus, David M. Shuker, William Bradshaw Amos, Sean Mayes
    Abstract:

    Female mating rate is an important variable for understanding the role of females in the evolution of mating systems. Polyandry influences patterns of sexual selection and has implications for sexual conflict over mating, as well as for wider issues such as patterns of gene flow and levels of genetic diversity. Despite this, remarkably few studies of insects have provided detailed estimates of polyandry in the wild. Here we combine behavioural and molecular genetic data to assess female mating frequency in wild populations of the two-spot ladybird, Adalia bipunctata (Coleoptera: Coccinellidae). We also explore patterns of sperm use in a controlled laboratory environment to examine how sperm from multiple males is used over time by females, to link mating with fertilization. We confirm that females are highly polyandrous in the wild, both in terms of population mating rates (approximately 20% of the population found in copula at any given time) and the number of males siring offspring in a single clutch (three to four males, on average). These patterns are consistent across two study populations. Patterns of sperm use in the laboratory show that the number of mates does not exceed the number of fathers, suggesting that females have little postcopulatory influence on paternity. Instead, longer copulations result in higher paternity for males, probably due to the transfer of larger numbers of sperm in multiple spermatophores. Our results emphasize the importance of combining field and laboratory data to explore mating rates in the wild.

  • Temporal effects of multiple mating on components of fitness in the two-spot ladybird, Adalia bipunctata (Coleoptera: Coccinellidae)
    European Journal of Entomology, 2007
    Co-Authors: Penelope R. Haddrill, David M. Shuker, Sean Mayes, Michael E. N. Majerus
    Abstract:

    Insects have provided much of the best evidence to date concerning possible costs and benefits of multiple mating, and here we investigate the benefits of polyandry in the two-spot ladybird, Adalia bipunctata, by attempting to replicate the highly promiscuous mating system in this species. We compared the temporal pattern of reproductive success of females mated multiple times to one male with that of females mated an equal number of times to multiple males, and found transient differences in offspring production and hatch rate over time. Our data suggest that polyandrous females benefit from multiple mating in some circumstances, but the patterns are complex. Following how both the costs and benefits to mating accrue over time will be necessary if we are to fully understand why polyandry evolves.

  • Spatial variation in the incidence of a sexually transmitted parasite of the ladybird beetle Adalia bipunctata (Coleoptera: Coccinellidae)
    European Journal of Entomology, 2006
    Co-Authors: K. Mary Webberley, John J. Sloggett, Michael E. N. Majerus, Matthew C. Tinsley, Gregory D D Hurst
    Abstract:

    Whilst sexually transmitted pathogens and parasites are common on insects and other animals, the factors affecting their incidence are currently uncertain. In order to understand the factors important in determining the presence of sexually transmitted parasites, it would be helpful to have information on intraspecific variation in incidence, as the causes of this variation are likely to reflect the likely causes of the presence/absence of sexually transmitted parasites across species. We therefore mapped the incidence of the parasite Coccipolipus hippodamiae within Europe on its primary host, the ladybird Adalia bipunctata. We observed that C. hippodamiae was present widely in Central, Southern and Eastern Europe, but was absent from northerly and north-western popula- tions. The cause of this pattern of incidence variation is discussed, with particular reference to the voltinism of the host. We also note that the distribution of C. hippodamiae on A. bipunctata is not congruent with that of another sexually transmitted parasite of this species, Hesperomyces virescens.

  • Multiple causes of male-killing in a single sample of the two-spot ladybird, Adalia bipunctata (Coleoptera: coccinellidae) from Moscow.
    Heredity, 2000
    Co-Authors: Michael E. N. Majerus, J. Hinrich, G V D Schulenburg, Ilia A. Zakharov
    Abstract:

    Thirty-six matrilines from a single Muscovite sample of Adalia bipunctata were assayed, using appropriate primers, for presence of the four male-killing symbionts known to infect this species of ladybird. All four, a Rickettsia, a Spiroplasma and two different strains of Wolbachia, were found to be present. Vertical transmission efficiencies were assessed from F1 and F2 families from each of the matrilines, and were found to differ significantly between symbionts. Potential explanations of the presence of four different male-killing symbionts within a single population, are considered.

  • Sexually transmitted disease in a promiscuous insect, Adalia bipunctata
    Ecological Entomology, 1995
    Co-Authors: Gregory D D Hurst, Linda E. Walker, Ilia A. Zakharov, Rosie G. Sharpe, Angela H. Broomfield, Tamsin M. O. Majerus, Michael E. N. Majerus
    Abstract:

    Abstract. 1Sexually transmitted diseases (STDs) have rarely been reported in insects and other invertebrates. The majority of those reported involve organisms where sexual transmission is augmented by either vertical (i.e. inherited) transmission, or horizontal transmission, independent of host sexual activity. 2We here demonstrate the existence of an STD in the coccinellid beetle Adalia bipunctata. This species bears a parasitic mite of the genus Coccipolipus. We show that, like many other podapolipid mites, this mite is transmitted between host individuals at a high rate during copulation. It also appears to be transmitted at a low rate between non-copulating individuals. 3We show that infected female A.bipunctata produced eggs at a reduced rate, and that the eggs produced by infected females have highly decreased viability. However, no effect of infection upon host longevity was observed. 4The results are discussed in relation to the incidences of sexually transmitted disease in invertebrates in general, the causes of disease symptoms, and the importance of this disease in the evolution of A.bipunctata.

Ilia A. Zakharov - One of the best experts on this subject based on the ideXlab platform.

Peter W. De Jong - One of the best experts on this subject based on the ideXlab platform.

  • Releases of a natural flightless strain of the ladybird beetle Adalia bipunctata reduce aphid-born honeydew beneath urban lime trees
    BioControl, 2012
    Co-Authors: S.t.e. Lommen, Peter W. De Jong, Thomas C. Holness, Alfons J. Van Kuik, Paul M. Brakefield
    Abstract:

    Aphids can cause major environmental problems in urban areas. One important problem is the annual outbreaks of lime aphid, Eucallipterus tiliae (L.) (Hemiptera: Aphididae), which spoil the surroundings of lime trees by depositing honeydew. To date no environmentally friendly method has been demonstrated to yield effective control of lime aphids. Attempts are made in some cities to control lime aphids by releasing larvae of the native two-spot ladybird beetle, Adalia bipunctata (L.) (Coleoptera: Coccinellidae). However, it is known that adult ladybird beetles disperse soon after release, and there is little indication they provide control of the aphids. Here, we demonstrate experimentally that releases of a flightless strain of A. bipunctata, obtained from natural variation in wing length, can reduce the impact of honeydew from lime aphid outbreaks on two species of lime in an urban environment. Both larvae and adult beetles were released, and we discuss the contribution of the flightless adults to the decline in honeydew.

  • Genetic linkage between melanism and winglessness in the ladybird beetle Adalia bipunctata.
    Genetica, 2012
    Co-Authors: Suzanne T E Lommen, Peter W. De Jong, Kees G Koops, Paul M. Brakefield
    Abstract:

    We report a case of genetic linkage between the two major loci underlying different wing traits in the two-spot ladybird beetle, Adalia bipunctata (L.) (Coleoptera: Coccinellidae): melanism and winglessness. The loci are estimated to be 38.8 cM apart on one of the nine autosomes. This linkage is likely to facilitate the unravelling of the genetics of these traits. These traits are of interest in the context of the evolution of intraspecific morphological diversity, and for the application of ladybird beetles in biological control programs.

  • Phenotypic plasticity of elytron length in wingless two-spot ladybird beetles, Adalia bipunctata (Coleoptera: Coccinellidae)
    European Journal of Entomology, 2005
    Co-Authors: S.t.e. Lommen, Peter W. De Jong, Paul M. Brakefield
    Abstract:

    Winglessness in the two-spot ladybird beetle Adalia bipunctata (L.) is determined by a single locus with the wingless allele recessive to the winged wildtype allele. The expression of the wingless trait is highly variable, with individuals missing a vari- able part of elytra and flight wings; the elytra and wings appear to be truncated rather than miniature in form. The degree of wing- lessness is partly determined genetically. Here we report on the phenotypic plasticity of the degree of winglessness. The environmental effect on elytron length relative to maximal elytron length in wingless phenotypes was studied by rearing offspring of single pair crosses of this form at a low (19°C) or high (29°C) temperature. Offspring reared at 19°C showed relatively longer elytra than those reared at 29°C.

  • The effect of female mating history on sperm precedence in the two-spot ladybird, Adalia bipunctata (Coleoptera, Coccinellidae)
    Behavioral Ecology, 1998
    Co-Authors: Peter W. De Jong, Paul M. Brakefield, Bas P. Geerinck
    Abstract:

    Effects of two different mating regimes on sperm precedence in the two-spot ladybird, Adalia bipunctata, were studied using the polymorphic gene for melanism as a marker for paternity. Virgin nonmelanic females (homozygous recessive) were mated to nonmelanic male(s) and then, after laying fertilized eggs, were mated to a melanic male of known genotype. The results after the two successive single matings showed a highly variable degree of paternity of the second male. Initial multiple mating with nonmelanic males did not alter the pattern of paternity after the subsequent single mating with a melanic male, but it had two other effects: (1) the female showed an increase in rejection behavior, and (2) a longer copulation was required for high success of the melanic male. Additional observations in which families were reared from beetles collected in copula in the field demonstrated that sperm competition also occurs under natural conditions. The outcome of the competition was variable with frequent sperm mixing. Key words: copulation duration, mating history, rejection, sperm competition, sperm precedence. [Behav Ecol 9:559-565 (1998)]

  • Climate and change in clines for melanism in the two–spot ladybird, Adalia bipunctata (Coleoptera: Coccinellidae)
    Proceedings of the Royal Society of London. Series B: Biological Sciences, 1998
    Co-Authors: Peter W. De Jong, Paul M. Brakefield
    Abstract:

    The polymorphic two-spot ladybird, Adalia bipunctata, shows clinal variation in the frequency with which melanic and non-melanic morphs occur. Here we show that the clines in melanism in The Netherlands have changed over the past two decades: they have become shallower. This change has coincided with an increase in local ambient spring temperatures at most meteorological stations close to the sampling sites. The potential contribution of thermal melanism to the change in the shape of the clines is discussed.