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Elad Chiel - One of the best experts on this subject based on the ideXlab platform.

  • Almost There: Transmission Routes of Bacterial Symbionts between Trophic Levels
    2016
    Co-Authors: Elad Chiel, Suzanne E Kelly, Mark K Asplen, Yuval Gottlieb, Moshe Inbar, Einat Zchori-fein, Tetsuya Adachi-hagimori, Martha S Hunter
    Abstract:

    Many intracellular microbial symbionts of arthropods are strictly vertically transmitted and manipulate their host’s reproduction in ways that enhance their own transmission. Rare horizontal transmission events are nonetheless necessary for symbiont spread to novel host lineages. Horizontal transmission has been mostly inferred from phylogenetic studies but the mechanisms of spread are still largely a mystery. Here, we investigated transmission of two distantly related bacterial symbionts – Rickettsia and Hamiltonella – from their host, the sweet potato whitefly, Bemisia tabaci, to three species of whitefly parasitoids: Eretmocerus emiratus, Eretmocerus eremicus and Encarsia pergandiella. We also examined the potential for vertical transmission of these whitefly symbionts between parasitoid generations. Using florescence in situ hybridization (FISH) and transmission electron microscopy we found that Rickettsia invades Eretmocerus larvae during development in a Rickettsia-infected host, persists in adults and in females, reaches the ovaries. However, Rickettsia does not appear to penetrate the oocytes, but instead is localized in the follicular epithelial cells only. Consequently, Rickettsia is not vertically transmitted in Eretmocerus wasps, a result supported by diagnostic polymerase chain reaction (PCR). In contrast, Rickettsia proved to be merely transient in the digestive tract of Encarsia and was excreted with the meconia before wasp pupation. Adults of all three parasitoid species frequently acquired Rickettsia via contact with infected whiteflies, most likely by feeding on the host hemolymph (host feeding), but the rate of infection declined sharply within a few days of wasps bein

  • characteristics phenotype and transmission of wolbachia in the sweet potato whitefly bemisia tabaci hemiptera aleyrodidae and its parasitoid Eretmocerus sp nr emiratus hymenoptera aphelinidae
    Environmental Entomology, 2014
    Co-Authors: Elad Chiel, Einat Zchorifein, Suzanne E Kelly, Alexandre M Harris, Marco Gebiola, Martha S Hunter
    Abstract:

    Wolbachia is a common intracellular bacterial endosymbiont of insects, causing a variety of effects including reproductive manipulations such as cytoplasmic incompatibility (CI). In this study, we characterized Wolbachia in the whitefly Bemisia tabaci and in the whitefly parasitoid Eretmocerus sp. nr. emiratus. We also tested for horizontal transmission of Wolbachia between and within trophic levels, and we determined the phenotype of Wolbachia in E. sp. nr. emiratus. Using multilocus sequence typing and phylogenetic analyses, we found that B. tabaci and E. sp. nr. emiratus each harbor a different and unique strain of Wolbachia. Both strains belong to the phylogenetic supergroup B. No evidence for horizontal transmission of Wolbachia between and within trophic levels was found in our study system. Finally, crossing results were consistent with a CI phenotype; when Wolbachia-infected E. sp. nr. emiratus males mate with uninfected females, wasp progeny survival dropped significantly, and the number of females was halved. This is the first description of CI caused by Wolbachia in the economically important genus Eretmocerus. Our study underscores the expectation that horizontal transmission events occur rarely in the dynamics of secondary symbionts such as Wolbachia, and highlights the importance of understanding the effects of symbionts on the biology of natural enemies.

  • Contagious sterility in the parasitoid wasp Eretmocerus mundus (Hymenoptera: Aphelinidae)
    Biocontrol Science and Technology, 2012
    Co-Authors: Elad Chiel, Dan Gerling, Shimon Steinberg, Johannette Klapwijk, K. J. F. Bolckmans, Einat Zchori-fein
    Abstract:

    Abstract The parasitoid wasp Eretmocerus mundus (Hymenoptera: Aphelinidae) is used commercially to control the sweet potato whitefly Bemisia tabaci (Homoptera: Aleyrodidae). Recently, a rapid deterioration of E. mundus populations has been documented under mass-rearing conditions. We found that deteriorating cultures consist of increasing proportions of sterile individuals, up to 90% within 6 months. Microscopic examination revealed that the gonads of wasps from both sexes are severely underdeveloped. Preliminary screening for potential pathogen candidates by means of polymerase chain reaction and denaturating-gradient gel electrophoresis did not provide any indication of possible causative agents.

  • almost there transmission routes of bacterial symbionts between trophic levels
    PLOS ONE, 2009
    Co-Authors: Elad Chiel, Einat Zchorifein, Tetsuya Adachihagimori, Suzanne E Kelly, Mark K Asplen, Yuval Gottlieb, Moshe Inbar, Martha S Hunter
    Abstract:

    Many intracellular microbial symbionts of arthropods are strictly vertically transmitted and manipulate their host's reproduction in ways that enhance their own transmission. Rare horizontal transmission events are nonetheless necessary for symbiont spread to novel host lineages. Horizontal transmission has been mostly inferred from phylogenetic studies but the mechanisms of spread are still largely a mystery. Here, we investigated transmission of two distantly related bacterial symbionts – Rickettsia and Hamiltonella – from their host, the sweet potato whitefly, Bemisia tabaci, to three species of whitefly parasitoids: Eretmocerus emiratus, Eretmocerus eremicus and Encarsia pergandiella. We also examined the potential for vertical transmission of these whitefly symbionts between parasitoid generations. Using florescence in situ hybridization (FISH) and transmission electron microscopy we found that Rickettsia invades Eretmocerus larvae during development in a Rickettsia-infected host, persists in adults and in females, reaches the ovaries. However, Rickettsia does not appear to penetrate the oocytes, but instead is localized in the follicular epithelial cells only. Consequently, Rickettsia is not vertically transmitted in Eretmocerus wasps, a result supported by diagnostic polymerase chain reaction (PCR). In contrast, Rickettsia proved to be merely transient in the digestive tract of Encarsia and was excreted with the meconia before wasp pupation. Adults of all three parasitoid species frequently acquired Rickettsia via contact with infected whiteflies, most likely by feeding on the host hemolymph (host feeding), but the rate of infection declined sharply within a few days of wasps being removed from infected whiteflies. In contrast with Rickettsia, Hamiltonella did not establish in any of the parasitoids tested, and none of the parasitoids acquired Hamiltonella by host feeding. This study demonstrates potential routes and barriers to horizontal transmission of symbionts across trophic levels. The possible mechanisms that lead to the differences in transmission of species of symbionts among species of hosts are discussed.

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

  • Almost There: Transmission Routes of Bacterial Symbionts between Trophic Levels
    2016
    Co-Authors: Elad Chiel, Suzanne E Kelly, Mark K Asplen, Yuval Gottlieb, Moshe Inbar, Einat Zchori-fein, Tetsuya Adachi-hagimori, Martha S Hunter
    Abstract:

    Many intracellular microbial symbionts of arthropods are strictly vertically transmitted and manipulate their host’s reproduction in ways that enhance their own transmission. Rare horizontal transmission events are nonetheless necessary for symbiont spread to novel host lineages. Horizontal transmission has been mostly inferred from phylogenetic studies but the mechanisms of spread are still largely a mystery. Here, we investigated transmission of two distantly related bacterial symbionts – Rickettsia and Hamiltonella – from their host, the sweet potato whitefly, Bemisia tabaci, to three species of whitefly parasitoids: Eretmocerus emiratus, Eretmocerus eremicus and Encarsia pergandiella. We also examined the potential for vertical transmission of these whitefly symbionts between parasitoid generations. Using florescence in situ hybridization (FISH) and transmission electron microscopy we found that Rickettsia invades Eretmocerus larvae during development in a Rickettsia-infected host, persists in adults and in females, reaches the ovaries. However, Rickettsia does not appear to penetrate the oocytes, but instead is localized in the follicular epithelial cells only. Consequently, Rickettsia is not vertically transmitted in Eretmocerus wasps, a result supported by diagnostic polymerase chain reaction (PCR). In contrast, Rickettsia proved to be merely transient in the digestive tract of Encarsia and was excreted with the meconia before wasp pupation. Adults of all three parasitoid species frequently acquired Rickettsia via contact with infected whiteflies, most likely by feeding on the host hemolymph (host feeding), but the rate of infection declined sharply within a few days of wasps bein

  • characteristics phenotype and transmission of wolbachia in the sweet potato whitefly bemisia tabaci hemiptera aleyrodidae and its parasitoid Eretmocerus sp nr emiratus hymenoptera aphelinidae
    Environmental Entomology, 2014
    Co-Authors: Elad Chiel, Einat Zchorifein, Suzanne E Kelly, Alexandre M Harris, Marco Gebiola, Martha S Hunter
    Abstract:

    Wolbachia is a common intracellular bacterial endosymbiont of insects, causing a variety of effects including reproductive manipulations such as cytoplasmic incompatibility (CI). In this study, we characterized Wolbachia in the whitefly Bemisia tabaci and in the whitefly parasitoid Eretmocerus sp. nr. emiratus. We also tested for horizontal transmission of Wolbachia between and within trophic levels, and we determined the phenotype of Wolbachia in E. sp. nr. emiratus. Using multilocus sequence typing and phylogenetic analyses, we found that B. tabaci and E. sp. nr. emiratus each harbor a different and unique strain of Wolbachia. Both strains belong to the phylogenetic supergroup B. No evidence for horizontal transmission of Wolbachia between and within trophic levels was found in our study system. Finally, crossing results were consistent with a CI phenotype; when Wolbachia-infected E. sp. nr. emiratus males mate with uninfected females, wasp progeny survival dropped significantly, and the number of females was halved. This is the first description of CI caused by Wolbachia in the economically important genus Eretmocerus. Our study underscores the expectation that horizontal transmission events occur rarely in the dynamics of secondary symbionts such as Wolbachia, and highlights the importance of understanding the effects of symbionts on the biology of natural enemies.

  • almost there transmission routes of bacterial symbionts between trophic levels
    PLOS ONE, 2009
    Co-Authors: Elad Chiel, Einat Zchorifein, Tetsuya Adachihagimori, Suzanne E Kelly, Mark K Asplen, Yuval Gottlieb, Moshe Inbar, Martha S Hunter
    Abstract:

    Many intracellular microbial symbionts of arthropods are strictly vertically transmitted and manipulate their host's reproduction in ways that enhance their own transmission. Rare horizontal transmission events are nonetheless necessary for symbiont spread to novel host lineages. Horizontal transmission has been mostly inferred from phylogenetic studies but the mechanisms of spread are still largely a mystery. Here, we investigated transmission of two distantly related bacterial symbionts – Rickettsia and Hamiltonella – from their host, the sweet potato whitefly, Bemisia tabaci, to three species of whitefly parasitoids: Eretmocerus emiratus, Eretmocerus eremicus and Encarsia pergandiella. We also examined the potential for vertical transmission of these whitefly symbionts between parasitoid generations. Using florescence in situ hybridization (FISH) and transmission electron microscopy we found that Rickettsia invades Eretmocerus larvae during development in a Rickettsia-infected host, persists in adults and in females, reaches the ovaries. However, Rickettsia does not appear to penetrate the oocytes, but instead is localized in the follicular epithelial cells only. Consequently, Rickettsia is not vertically transmitted in Eretmocerus wasps, a result supported by diagnostic polymerase chain reaction (PCR). In contrast, Rickettsia proved to be merely transient in the digestive tract of Encarsia and was excreted with the meconia before wasp pupation. Adults of all three parasitoid species frequently acquired Rickettsia via contact with infected whiteflies, most likely by feeding on the host hemolymph (host feeding), but the rate of infection declined sharply within a few days of wasps being removed from infected whiteflies. In contrast with Rickettsia, Hamiltonella did not establish in any of the parasitoids tested, and none of the parasitoids acquired Hamiltonella by host feeding. This study demonstrates potential routes and barriers to horizontal transmission of symbionts across trophic levels. The possible mechanisms that lead to the differences in transmission of species of symbionts among species of hosts are discussed.

Tao Wang - One of the best experts on this subject based on the ideXlab platform.

  • the effects of temperature on the development fecundity and mortality of Eretmocerus warrae is Eretmocerus warrae better adapted to high temperatures than encarsia formosa
    Pest Management Science, 2019
    Co-Authors: Tao Wang, Michael A Keller, Katja Hogendoorn
    Abstract:

    BACKGROUND: Eretmocerus warrae (Hymenoptera: Aphelinidae) is a parasitoid of the glasshouse whitefly, Trialeurodes vaporariorum (Hemiptera: Aleyrodidae). Here, we compare its potential as a biological control agent at high temperatures to that of Encarsia formosa (Hymenoptera: Aphelinidae), a wasp which is widely sold for control of T. vaporariorum. RESULTS: Eretmocerus warrae attained the highest estimated developmental rate at 31.4 °C and the maximum oviposition rate at 30.5 °C. Developmental times of E. warrae at fluctuating temperatures that simulate night‐day patterns were similar to those predicted based on constant temperatures. Above the optimum temperature, E. warrae tolerated higher constant temperatures than En. formosa during development and as adults. Using a ramping temperature approach, the critical thermal maximum for adult E. warrae was significantly higher than that of adult En. formosa. CONCLUSION: Eretmocerus warrae is better adapted to high temperatures than En. formosa, and could therefore be a complementary or superior biological control agent during summer months in hot regions. © 2018 Society of Chemical Industry

Tongxian Liu - One of the best experts on this subject based on the ideXlab platform.

  • whitefly parasitoids distribution life history bionomics and utilization
    Annual Review of Entomology, 2015
    Co-Authors: Tongxian Liu, Philip A Stansly, Dan Gerling
    Abstract:

    Whiteflies are small hemipterans numbering more than 1,550 described species, of which about 50 are agricultural pests. Adults are free-living, whereas late first to fourth instars are sessile on the plant. All known species of whitefly parasitoids belong to Hymenoptera; two genera, Encarsia and Eretmocerus, occur worldwide, and others are mostly specific to different continents. All parasitoid eggs are laid in—or in Eretmocerus, under—the host. They develop within whitefly nymphs and emerge from the fourth instar, and in Cales, from either the third or fourth instar. Parasitized hosts are recognized by conspecifics, but super- and hyperparasitism occur. Dispersal flights are influenced by gender and mating status, but no long-range attraction to whitefly presence on leaves is known. Studies on En. formosa have laid the foundation for behavioral studies and biological control in general. We review past and ongoing studies of whitefly parasitoids worldwide, updating available information on species diversity, biology, behavior, tritrophic interactions, and utilization in pest management.

  • interactions among two species of Eretmocerus hymenoptera aphelinidae two species of whiteflies homoptera aleyrodidae and tomato
    Environmental Entomology, 2002
    Co-Authors: S M Greenberg, W A Jones, Tongxian Liu
    Abstract:

    Abstract Laboratory experiments were conducted to determine the influence of two tomato (Lycopersicum esculentum Miller) varieties (‘Trust’ and ‘Floridade’) on the biology of two whitefly species, Bemisia argentifolii Bellows & Perring and Trialeurodes vaporariorum (Westwood), and the interactions of host plant and whiteflies on the biology and parasitization of two parasitoid species, Eretmocerus eremicus Rose & Zolnerowich (native) and Eretmocerus mundus Mercet (exotic). Natural mortality, developmental time, and fecundity of B. argentifolii were not significantly different from those of T. vaporariorum on either tomato variety. The two species of Eretmocerus responded differently to the whitefly hosts. Eretmocerus mundus developed significantly faster, produced more progeny, and had greater parasitism and rate of emergence in B. argentifolii than in T. vaporariorum. Eretmocerus eremicus performed similarly on both whitefly species except that its females deposited more eggs in B. argentifolii than in T...

  • apparent parasitism ofbemisia argentifolii homoptera aleyrodidae by aphelinidae hymenoptera on vegetable crops and associated weeds in south florida
    Biological Control, 1997
    Co-Authors: Philip A Stansly, David J Schuster, Tongxian Liu
    Abstract:

    Apparent parasitism of silverleaf whitefly, Bemisia argentifolii Bellows & Perring, by Encarsia spp. and Eretmocerus spp. was surveyed on several crop and weed species in southern Florida from 1990 to 1995. Apparent parasitism levels varied between crops, seasons, and years, but generally were high on okra and cotton among crops, lantana and Spanish needles among weeds. E. pergandiella Howard was the most dominant parasitoid species (43.7‐100%), whereas incidence of E. transvena (Timberlake), E. nigricephala Dozier, E. quaintancei Howard, and Eretmocerus nr. californicusHoward varied by host plant and location. A greater proportion of B. argentifolii was parasitized by E. pergandiella on tomato than on collard and eggplant in a greenhouse choice test. r 1997 Academic Press

Katja Hogendoorn - One of the best experts on this subject based on the ideXlab platform.

  • the effects of temperature on the development fecundity and mortality of Eretmocerus warrae is Eretmocerus warrae better adapted to high temperatures than encarsia formosa
    Pest Management Science, 2019
    Co-Authors: Tao Wang, Michael A Keller, Katja Hogendoorn
    Abstract:

    BACKGROUND: Eretmocerus warrae (Hymenoptera: Aphelinidae) is a parasitoid of the glasshouse whitefly, Trialeurodes vaporariorum (Hemiptera: Aleyrodidae). Here, we compare its potential as a biological control agent at high temperatures to that of Encarsia formosa (Hymenoptera: Aphelinidae), a wasp which is widely sold for control of T. vaporariorum. RESULTS: Eretmocerus warrae attained the highest estimated developmental rate at 31.4 °C and the maximum oviposition rate at 30.5 °C. Developmental times of E. warrae at fluctuating temperatures that simulate night‐day patterns were similar to those predicted based on constant temperatures. Above the optimum temperature, E. warrae tolerated higher constant temperatures than En. formosa during development and as adults. Using a ramping temperature approach, the critical thermal maximum for adult E. warrae was significantly higher than that of adult En. formosa. CONCLUSION: Eretmocerus warrae is better adapted to high temperatures than En. formosa, and could therefore be a complementary or superior biological control agent during summer months in hot regions. © 2018 Society of Chemical Industry