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Andrew Polaszek - One of the best experts on this subject based on the ideXlab platform.

G A Evans - One of the best experts on this subject based on the ideXlab platform.

  • Additions to the Encarsia parasitoids (Hymenoptera: Aphelinidae) of the Bemisia tabaci -complex (Hemiptera: Aleyrodidae)
    Bulletin of Entomological Research, 1997
    Co-Authors: G A Evans, Andrew Polaszek
    Abstract:

    Four new species of Encarsia, E. lanceolata sp. n., E. paracitrella sp. n., E. pseudocitrella sp. n. and E. unicitrella sp. n. are described and illustrated. All four parasitoid species were reared from the Bemisia tabaci-complex and/or other whitefly hosts in the Neotropical region. Encarsia paracitrella, E. pseudocitrella and E. unicitrella are extremely closely related, to each other and to E. citrella (Howard). A diagnosis is therefore given for the E. citrella-complex, with a key to the four currently included species. For E. citrella (Howard) a lectotype is designated, the male is described and illustrated for the first time, and the female is redescribed and illustrated. A key and a modification to an existing key are provided to facilitate the identification of the five species treated.

  • Encarsia parasitoids of bemisia tabaci hymenoptera aphelinidae homoptera aleyrodidae a preliminary guide to identification
    Bulletin of Entomological Research, 1992
    Co-Authors: Andrew Polaszek, G A Evans, F D Bennett
    Abstract:

    A key is provided for the recognition of previously described Encarsia species which are known to attack the tobacco whitefly, Bemisia tabaci (Genna-dius). 28 nominal species are included, of which type material has been examined for 22. Eight new synonymies are proposed: Encarsia aleyrodis (Mercet) and E. partenopea Masi are both synonymized with E. inaron (Walker); E. bemi-siae (Ishii) is synonymized with E. transvena (Timberlake); E. citri (Ishii) is synonymized with E. strenua (Silvestri), E. angelica Howard and E. deserti Rivnay & Gerling are both synonymized with E. luteola Howard; E. perspicuipennis (Girault) is synonymized with E. quaintancei (Howard); E. tabacivora Viggiani is synonymized with E. pergandiella Howard. E. hispida De Santis is removed from synonymy with E. meritoria Gahan. A lectotype is designated for E. porteri (Mercet). The known distributions and alternative hosts of Encarsia species attacking B. tabaci are provided as well as references to biology and notes on their use in biological control.

H. Schmutterer - One of the best experts on this subject based on the ideXlab platform.

  • investigations on side effects of margosan o on Encarsia formosa gah hym aphelinidae parasitoid of the greenhouse whitefly trialeurodes vaporariorum westw hom aleyrodidae
    Journal of Applied Entomology, 1993
    Co-Authors: M. Feldhege, H. Schmutterer
    Abstract:

    In order to achieve more information on the side-effects of neem products on beneficial organisms, investigations were conducted on Encarsia formosa, a parasitoid of the greenhouse whitefly Trialeurodes vaporariorum. Of special interest was the evaluation of the influence on the parasitoid's longevity, emergence and capacity of parasitism after indirect contact with Margosan-O. The results showed that the application of 10 ppm azadirachtin was relatively non-toxic, whereas the concentration of 20 ppm led to a slight but significant reduction of the fitness of E. formosa. Zusammenfassung Untersuchungen zu Nebenwirkungen von Margosan-O auf Encarsia formosa Gah. (Hym., Aphelinidae) bei der Bekampfung der Weisen Fliege Trialeurodes vaporariorum Westw. (Hom., Aleyrodidae) Um zu genaueren Erkenntnissen bezuglich der Nebenwirkungen von Niemextrakten auf Nutzlinge zu gelangen, wurden Untersuchungen an Encarsia formosa, einem Parasitoiden der Weisen Fliege Trialeurodes vaporariorum, durchgefuhrt. Von besonderem Interesse war hierbei die Evaluierung von Nebenwirkungen auf die Lebensdauer, die Schlupfrate und die Parasitierungsleistung des Parasitoiden nach Behandlung parasitierter Puparien von T. vaporariorum mit Margosan-O. Die Ergebnisse zeigen, das die Anwendung einer niedriger konzentrierten Formulierung von Margosan-O (10 ppm Azadirachtin) relativ wenig toxisch wirkte, wahrend eine geringe, jedoch signifikante Verminderung der Fitnes von E. formosa nach Behandlung mit der hoher dosierten Variante von 20 ppm zu verzeichnen war.

  • Investigations on side‐effects of Margosan‐O on Encarsia formosa Gah. (Hym., Aphelinidae), parasitoid of the greenhouse whitefly, Trialeurodes vaporariorum Westw. (Hom., Aleyrodidae)
    Journal of Applied Entomology, 1993
    Co-Authors: M. Feldhege, H. Schmutterer
    Abstract:

    In order to achieve more information on the side-effects of neem products on beneficial organisms, investigations were conducted on Encarsia formosa, a parasitoid of the greenhouse whitefly Trialeurodes vaporariorum. Of special interest was the evaluation of the influence on the parasitoid's longevity, emergence and capacity of parasitism after indirect contact with Margosan-O. The results showed that the application of 10 ppm azadirachtin was relatively non-toxic, whereas the concentration of 20 ppm led to a slight but significant reduction of the fitness of E. formosa. Zusammenfassung Untersuchungen zu Nebenwirkungen von Margosan-O auf Encarsia formosa Gah. (Hym., Aphelinidae) bei der Bekampfung der Weisen Fliege Trialeurodes vaporariorum Westw. (Hom., Aleyrodidae) Um zu genaueren Erkenntnissen bezuglich der Nebenwirkungen von Niemextrakten auf Nutzlinge zu gelangen, wurden Untersuchungen an Encarsia formosa, einem Parasitoiden der Weisen Fliege Trialeurodes vaporariorum, durchgefuhrt. Von besonderem Interesse war hierbei die Evaluierung von Nebenwirkungen auf die Lebensdauer, die Schlupfrate und die Parasitierungsleistung des Parasitoiden nach Behandlung parasitierter Puparien von T. vaporariorum mit Margosan-O. Die Ergebnisse zeigen, das die Anwendung einer niedriger konzentrierten Formulierung von Margosan-O (10 ppm Azadirachtin) relativ wenig toxisch wirkte, wahrend eine geringe, jedoch signifikante Verminderung der Fitnes von E. formosa nach Behandlung mit der hoher dosierten Variante von 20 ppm zu verzeichnen war.

F D Bennett - One of the best experts on this subject based on the ideXlab platform.

  • Encarsia parasitoids of bemisia tabaci hymenoptera aphelinidae homoptera aleyrodidae a preliminary guide to identification
    Bulletin of Entomological Research, 1992
    Co-Authors: Andrew Polaszek, G A Evans, F D Bennett
    Abstract:

    A key is provided for the recognition of previously described Encarsia species which are known to attack the tobacco whitefly, Bemisia tabaci (Genna-dius). 28 nominal species are included, of which type material has been examined for 22. Eight new synonymies are proposed: Encarsia aleyrodis (Mercet) and E. partenopea Masi are both synonymized with E. inaron (Walker); E. bemi-siae (Ishii) is synonymized with E. transvena (Timberlake); E. citri (Ishii) is synonymized with E. strenua (Silvestri), E. angelica Howard and E. deserti Rivnay & Gerling are both synonymized with E. luteola Howard; E. perspicuipennis (Girault) is synonymized with E. quaintancei (Howard); E. tabacivora Viggiani is synonymized with E. pergandiella Howard. E. hispida De Santis is removed from synonymy with E. meritoria Gahan. A lectotype is designated for E. porteri (Mercet). The known distributions and alternative hosts of Encarsia species attacking B. tabaci are provided as well as references to biology and notes on their use in biological control.

Martha S Hunter - One of the best experts on this subject based on the ideXlab platform.

  • A revision of the Encarsia pergandiella species complex (Hymenoptera: Aphelinidae) shows cryptic diversity in parasitoids of whitefly pests
    Systematic Entomology, 2016
    Co-Authors: Marco Gebiola, Martha S Hunter, Maurilia M. Monti, Massimo Giorgini, Roishene C. Johnson, James B. Woolley, Paolo A. Pedata
    Abstract:

    Encarsia pergandiella Howard, described from North America (USA), and Encarsia tabacivora Viggiani, described from South America (Brazil) (Hymenoptera: Aphelinidae), are two formally recognized taxonomic entities, that have been treated by several authors as synonyms due to lack of strong diagnostic characters. Taxonomy of these species is further complicated because several populations, geographically separated and differing in their biology, have been included under the concept of E. pergandiella. Among these, a population originally collected in Brazil and introduced to North America reproduces by thelytokous parthenogenesis and is infected by the symbiont Cardinium, while a morphologically indistinguishable population, naturally occurring in Texas, is biparental and infected by a related strain of Cardinium that induces cytoplasmic incompatibility. A third population known from California and introduced to the Old World is biparental and uninfected by intracellular symbionts. While adult females of the first two populations have entirely light yellow bodies and pupate face up (light form), those of the third population have largely brown bodies and pupate face down (dark form). Other dark form populations are known from Texas, Florida and New York. Because these parasitoids are economically important biological control agents of cosmopolitan whitefly pests, it is critical to characterize them correctly. In this study, we integrated molecular and morphometric analyses to substantiate observed differences in biological traits, and resolve the complicated taxonomy of this species complex. We sequenced the mitochondrial cytochrome c oxidase subunit I gene and the D2 region of the ribosomal 28S gene for individuals of both light form (from Texas and Brazil) and dark form (from California, Texas, Italy and Canary Islands) originating from laboratory cultures or collected in the field. Phylogenetic analysis unambiguously distinguished three well-supported groups corresponding to the Texas light form, the Brazil light form and the dark form. Individuals of these three groups, in combination with all available type material (E. pergandiella, its synonym Encarsia versicolor Girault and E. tabacivora) and additional museum specimens of the dark form from New York and Italy, were subjected to multivariate morphometric analyses using Burnaby principal component analysis followed by a linear discriminant analysis, and multivariate ratio analysis. Overall, the analyses showed that: (i) E. pergandiella and E. tabacivora are two distinct species; (ii) the thelytokous Brazil light form corresponds to E. tabacivora; (iii) the biparental Texas light form is a new species formally described here as Encarsia suzannae sp.n.; (iv) two new biparental species can be referred to the dark form, one described as Encarsia gennaroi sp.n. including the populations sampled in California, Texas, Italy and Canary Islands, and the other corresponding to the population from New York described as Encarsia marthae sp.n. A dichotomous key for both sexes of the species of the E. pergandiella complex is provided for identification. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:278475A0-C2C4-4400-A042-A5716457829D.

  • Cytoplasmic incompatibility and multiple symbiont infection in the ash whitefly parasitoid, Encarsia inaron
    Biological Control, 2006
    Co-Authors: Steve J Perlman, Einat Zchori-fein, Suzanne E Kelly, Martha S Hunter
    Abstract:

    Abstract Terrestrial arthropods are commonly infected with maternally inherited symbionts that cause reproductive incompatibilities between hosts with differing infection status. Such symbionts can have major effects on the efficacy of a biological control program if releases are comprised of mixtures of differentially infected individuals. In this study, the ash whitefly parasitoid, Encarsia inaron (Hymenoptera: Aphelinidae) from Arizona was surveyed for the presence of heritable bacterial symbionts; experiments were also performed to test for two phenotypes known to be caused by Encarsia symbionts—cytoplasmic incompatibility and changes in oviposition behavior and host use. E. inaron has successfully reduced ash whitefly to non-pest status in all three locations it has been released (California, Arizona, and North Carolina) and is also notable as one of the only Encarsia species that is not autoparasitic, with both male and female wasps developing as primary parasitoids of whiteflies. We show that E. inaron is infected with both Wolbachia and Cardinium. While there was no effect of the symbionts on oviposition behavior or host use, crosses between doubly infected male wasps and uninfected females resulted in a severe reduction in the number of female offspring; male offspring production was unaffected. This study thus serves as a further warning that ascribing a phenotype to a symbiont with confidence depends on eliminating the possibility of a mixed infection, and establishes E. inaron as a useful model for dissecting Wolbachia–Cardinium interactions.

  • Characterization of a 'Bacteroidetes' symbiont in Encarsia wasps (Hymenoptera: Aphelinidae): proposal of 'Candidatus Cardinium hertigii'.
    International journal of systematic and evolutionary microbiology, 2004
    Co-Authors: Einat Zchori-fein, Steve J Perlman, Suzanne E Kelly, Nurit Katzir, Martha S Hunter
    Abstract:

    Previously, analysis of 16S rDNA sequences placed a newly discovered lineage of bacterial symbionts of arthropods in the 'Bacteroidetes'. This symbiont lineage is associated with a number of diverse host reproductive manipulations, including induction of parthenogenesis in several Encarsia parasitoid wasps (Hymenoptera: Aphelinidae). In this study, electron microscopy and phylogenetic analysis of the 16S rRNA and gyrB genes of symbionts from Encarsia hispida and Encarsia pergandiella are used to describe and further characterize these bacteria. Phylogenetic analyses based on these two genes showed that the Encarsia symbionts are allied with the Cytophaga aurantiaca lineage within the 'Bacteroidetes', with their closest described relative being the acanthamoeba symbiont 'Candidatus Amoebophilus asiaticus'. The Encarsia symbionts share 97 % 16S rDNA sequence similarity with Brevipalpus mite and Ixodes tick symbionts and 88 % sequence similarity with 'Candidatus A. asiaticus'. Electron microscopy revealed that many of the bacteria found in the ovaries of the two Encarsia species contained a regular, brush-like array of microfilament-like structures that appear to be characteristic of the symbiont. Finally, the role of this bacterium in parthenogenesis induction in E. hispida was confirmed. Based on phylogenetic analyses and electron microscopy, classification of the symbionts from Encarsia as 'Candidatus Cardinium hertigii' is proposed.