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Sample records for aphidius colemani viereck

  1. Fitness Effects of Food Resources on the Polyphagous Aphid Parasitoid, Aphidius colemani Viereck (Hymenoptera: Braconidae: Aphidiinae).

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    Charles, Jennifer J; Paine, Timothy D

    2016-01-01

    Conservation biological control involving the polyphagous aphid parasitoid, Aphidius colemani Viereck, may include provisioning resources from a variety of plant sources. The fitness of adult A. colemani was enhanced with the provision of food resources such as floral nectar from a range of both native and introduced plant species and aphid honeydew under laboratory conditions. However, enhanced fitness appeared to be species specific rather than associated with the whether the plant was a native or an introduced species. Parasitoid survival and fecundity were enhanced significantly in response to the availability of floral nectar and honeydew compared to the response to available extrafloral nectar. These positive effects on the parasitoid's reproductive activity can improve the effectiveness of conservation biological control in nursery production systems because of the abundance and diversity of floral resources within typical production areas. Additionally, surrounding areas of invasive weeds and native vegetation could serve as both floral resources and honeydew food resources for A. colemani.

  2. Ecological Interactions Affecting the Efficacy of Aphidius colemani in Greenhouse Crops

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    Sara G. Prado

    2015-06-01

    Full Text Available Aphidius colemani Viereck (Hymenoptera: Braconidae is a solitary endoparasitoid used for biological control of many economically important pest aphids. Given its widespread use, a vast array of literature on this natural enemy exists. Though often highly effective for aphid suppression, the literature reveals that A. colemani efficacy within greenhouse production systems can be reduced by many stressors, both biotic (plants, aphid hosts, other natural enemies and abiotic (climate and lighting. For example, effects from 3rd and 4th trophic levels (fungal-based control products, hyperparasitoids can suddenly decimate A. colemani populations. But, the most chronic negative effects (reduced parasitoid foraging efficiency, fitness seem to be from stressors at the first trophic level. Negative effects from the 1st trophic level are difficult to mediate since growers are usually constrained to particular plant varieties due to market demands. Major research gaps identified by our review include determining how plants, aphid hosts, and A. colemani interact to affect the net aphid population, and how production conditions such as temperature, humidity and lighting affect both the population growth rate of A. colemani and its target pest. Decades of research have made A. colemani an essential part of biological control programs in greenhouse crops. Future gains in A. colemani efficacy and aphid biological control will require an interdisciplinary, systems approach that considers plant production and climate effects at all trophic levels.

  3. Grain Diversity Effects on Banker Plant Growth and Parasitism by Aphidius colemani

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    Travis McClure

    2015-09-01

    Full Text Available Green peach aphid (Myzus persicae Sulzer (Hemiptera: Aphididae is a serious greenhouse pest with a short generation time, parthenogenetic reproduction and a broad host range. Banker plant systems are becoming a more common form of biological control for this pest. This system consists of grain “banker plants” infested with R. padi, an alternative hosts for the parasitoid Aphidius colemani. Thus A. colemani can reproduce on the banker plant when M. persicae populations are low. This system can increase pest suppression; however, like other biological control tools, efficacy is inconsistent. One reason is because several different grain species have been used. Our studies determined if there were benefits to planting interspecific mixture banker plants, similar to when open agricultural systems use mixed cropping. Our study found that although banker plants grow larger when planted as mixtures this added plant growth does not increase in the number of aphids, or mummies an individual banker plant can sustain. Rye banker plants grew larger, and sustained more mummies than the other species we tested, but barley banker plants resulted in a similar number of aphids in a more condensed area. Ultimately, we did not see any differences in pest suppression between monoculture banker plants, mixture banker plants, or our augmentative release treatment. However, using banker plants resulted in more female parasitoids than the augmentative release, a benefit to using banker plant systems.

  4. Infection of host plants by Cucumber mosaic virus increases the susceptibility of Myzus persicae aphids to the parasitoid Aphidius colemani.

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    Mauck, Kerry E; De Moraes, Consuelo M; Mescher, Mark C

    2015-06-04

    Plant viruses can profoundly alter the phenotypes of their host plants, with potentially far-reaching implications for ecology. Yet few studies have explored the indirect, host-mediated, effects of plant viruses on non-vector insects. We examined how infection of Cucurbita pepo plants by Cucumber mosaic virus (CMV) impacted the susceptibility of aphids (Myzus persicae) to attack by the parasitoid wasp Aphidius colemani. In semi-natural foraging assays, we observed higher rates of aphid parasitism on infected plants compared to healthy plants. Subsequent experiments revealed that this difference is not explained by different attack rates on plants differing in infection status, but rather by the fact that parasitoid larvae successfully complete their development more often when aphid hosts feed on infected plants. This suggests that the reduced nutritional quality of infected plants as host for aphids--documented in previous studies--compromises their ability to mount effective defenses against parasitism. Furthermore, our current findings indicate that the aphid diet during parasitoid development (rather than prior to wasp oviposition) is a key factor influencing resistance. These findings complement our previous work showing that CMV-induced changes in host plant chemistry alter patterns of aphid recruitment and dispersal in ways conducive to virus transmission.

  5. Asociaciones áfido-parasitoide (Hemiptera: Aphididae; Hymenoptera: Braconidae, Aphidiinae en cultivos hortícolas orgánicos en Los Cardales, Buenos Aires, Argentina

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    Andrea V. ANDORNO

    2007-01-01

    Full Text Available Diez especies de áfidos (Hemiptera: Aphididae se hallaron parasitados por siete especies de parasitoides (Hymenoptera: Braconidae, Aphidiinae en cultivos hortícolas orgánicos. Myzus persicae (Sulzer fue el áfido más frecuentemente encontrado sobre una amplia variedad de cultivos, y con mayor diversidad de parasitoides asociados. Aphidius colemani Viereck fue el afidiino más usual, que ataca varias especies de áfidos. Ocho asociaciones tritróficas, involucrando Aphidius matricariae Haliday, han sido registradas por primera vez para la Argentina.

  6. Aphid parasitoids that occur on wheat crops of Northeast of the Parana State with recovery of Aphidius rhopalosiphi in BrazilParasitoides de pulgões-do-trigo que ocorrem no Norte do estado do Paraná e recaptura de Aphidius rhopalosiphi no Brasil

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    Adriano Thibes Hoshino

    2012-02-01

    Full Text Available Aphids (Hemiptera: Aphididae are the main pest of wheat (Hemiptera: Aphididae in several countries. In Brazil, the Biological Control of Wheat Aphids released millions of aphid parasitoids (Hymenoptera: Braconidae and Aphelinidae on wheat fields and in the present moment the chemical control is rarely necessary. However, since the 80’s few studies was carried out to evaluate the species established in Brazil. For this reason, the aim of this study was to record the species of aphid parasitoids that occur in wheat in the northern region of Parana state, Brazil. Four commercial wheat fields were investigated in the agricultural years of 2008 and 2009. The aphid parasitoids were captured with traps (Moericke and Malaise and aphid mummified were collected. In total, six species of parasitoids were found, Aphidius colemani, A. uzbekistanicus, A. ervi, Aphidius rhopalosiphi, Diaeretiella rapae e Lysiphlebus testaceipes. These results contribute with the register of three exotic species in Parana, and confirm the establishment of A. rhopalosiphi in the country. We emphasize the need for further studies in other regions of the country, as other species introduced also need to have their establishment confirmed.Os pulgões (Hemiptera: Aphididae são pragas de extrema importância em cereais de inverno no mundo todo. No Brasil, o programa Controle Biológico de Pulgões do Trigo liberou milhões de parasitoides (Hymenoptera: Braconidae e Aphelinidae nas áreas tritícolas, reduzindo expressivamente a população da praga, e atualmente raramente o controle químico se faz necessário. Entretanto, desde a década de 80 poucos trabalhos de campo tem sido realizados para verificar as espécies efetivamente estabelecidas no País. Por esta razão, este estudo objetivou registrar as espécies de parasitoides de pulgões ocorrentes em lavouras de trigo na região Norte no Paraná. O trabalho foi realizado em quatro áreas comerciais de trigo, durante as safras

  7. Asociaciones áfido-parasitoide (Hemiptera: Aphididae; Hymenoptera: Braconidae, Aphidiinae en cultivos hortícolas orgánicos en Los Cardales, Buenos Aires, Argentina Aphid-parasitoid associations (Hemiptera: Aphididae; Hymenoptera: Braconidae, Aphidiinae on organic vegetable crops in Los Cardales, Buenos Aires, Argentina

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    Andrea V. Andorno

    2007-07-01

    Full Text Available Diez especies de áfidos (Hemiptera: Aphididae se hallaron parasitados por siete especies de parasitoides (Hymenoptera: Braconidae, Aphidiinae en cultivos hortícolas orgánicos. Myzus persicae (Sulzer fue el áfido más frecuentemente encontrado sobre una amplia variedad de cultivos, y con mayor diversidad de parasitoides asociados. Aphidius colemani Viereck fue el afidiino más usual, que ataca varias especies de áfidos. Ocho asociaciones tritróficas, involucrando Aphidius matricariae Haliday, han sido registradas por primera vez para la Argentina.Ten aphid species (Hemiptera: Aphididae were found parasitized by seven aphid parasitoid species (Hymenoptera: Braconidae, Aphidiinae on organic vegetable crops. Myzus persicae (Sulzer was the most frequent aphid found on a wide variety of crops, with the largest parasitoid diversity associated. Aphidius colemani Viereck was the most frequent aphidiine attacking several species of aphids. Eight tritrophic associations involving Aphidius matricariae Haliday are reported for the first time for Argentina.

  8. Effects of feeding frequency and sugar concentration on behavior and longevity of the adult aphid parasitoid: Aphidius ervi (Haliday) (Hymenoptera: Braconidae)

    NARCIS (Netherlands)

    Azzouz, H.; Giordanengo, P.; Wäckers, F.L.; Kaiser, L.

    2004-01-01

    Aphidius ervi (Haliday) (Hymenoptera: Braconidae) is a solitary aphid endoparasitoid. Adults feed on honeydew and possibly on other sugar sources such as nectar. Sugar sources can vary qualitatively and quantitatively according to biotic factors and environmental conditions. Experiments were conduct

  9. Larval competition between Aphidius ervi and Praon volucre (Hymenoptera: Braconidae: Aphidiinae) in Macrosiphum euphorbiae (Hemiptera: Aphididae).

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    Sidney, Lívia Alvarenga; Bueno, Vanda Helena Paes; Lins, Juracy Caldeira; Sampaio, Marcus Vinicius; Silva, Diego Bastos

    2010-10-01

    Interspecific competition between parasitoid larvae may influence the size, structure, and stability of the population, leading to a reduction in total parasitism and thus restricting the pest control. Aphidius ervi (Haliday) and Praon volucre (Haliday) are endoparasitoids that possess a wide host range and present considerable potential for the biological control of the aphid Macrosiphum euphorbiae (Thomas). The larval competition between A. ervi and P. volucre, and the possible intrinsic competitive superiority of one of the parasitoids in M. euphorbiae, have been studied. In single parasitism experiments, mated parasitoid females (n=10) were maintained individually in contact with M. euphorbiae hosts (n=30) inside petri dishes containing lettuce leaf discs and maintained in environmental chamber at 22 ± 1°C, 70 ± 10% RH, and 12-h photophase. The multiple parasitism experiments consisted of exposing single parasitized aphids (n=120) to the second parasitoid species. Two oviposition events were performed with a 4-h interval between them, namely the following: sequence A (oviposition by A. ervi, followed by P. volucre) and sequence B (oviposition by P. volucre, followed by A. ervi). Oviposition sequence A generated 24 A. ervi and 55 P. volucre adults, whereas oviposition sequence B generated 23 and 49 adults. P. volucre is an intrinsically superior competitor compared with A. ervi, and the use of the two species simultaneously may result in competitive exclusion and influence the stability of the parasitoid population.

  10. [Quality of different aphids species as hosts for the parasitoid Aphidius ervi Haliday (Hymenoptera: Braconidae: Aphidiinae)].

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    Sidney, Lívia A; Bueno, Vanda H P; Lins, Juracy C; Silva, Diego B; Sampaio, Marcus V

    2010-01-01

    The suitability of Macrosiphum euphorbiae (Thomas), Aulacorthum solani (Kaltenbach) and Acyrthosiphon kondoi Shinji (Hemiptera: Aphididae) as hosts for the aphid parasitoid Aphidius ervi Haliday was evaluated by assessing host size, host preference, and host quality. Tests were carried out in an environmental chamber at 22±1ºC, 70±10% RH and 12h photophase. Replicates (11) consisted of one 24h-old mated female of A. ervi without a previous oviposition experience. Female was released into a Petri dish (5 cm) with 20 2nd and 3rd instars of one of each aphid species tested on a leaf disc of the host plant onto a 1% water-agar layer. Parasitoid emergency was lower in A. kondoi (78.7%) compared to M. euphorbiae (92.2%) and A. solani (91.7%). Acyrthosiphon kondoi (0.36 mm) was the smallest host. The parasitoid showed preference (74.0% parasitism) for M. euphorbiae, the largest host (hind tibia length=0.73 mm), which in turn yielded larger A. ervi females (0.75 mm).

  11. Placenta-like structure of the aphid endoparasitic wasp Aphidius ervi: a strategy of optimal resources acquisition.

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    Ahmed Sabri

    Full Text Available Aphidius ervi (Hymenoptera: Braconidae is an entomophagous parasitoid known to be an effective parasitoid of several aphid species of economic importance. A reduction of its production cost during mass rearing for inundative release is needed to improve its use in biological control of pests. In these contexts, a careful analysis of its entire development phases within its host is needed. This paper shows that this parasitoid has some characteristics in its embryological development rather complex and different from most other reported insects, which can be phylogenetically very close. First, its yolkless egg allows a high fecundity of the female but force them to hatch from the egg shell rapidly to the host hemocoel. An early cellularisation allowing a rapid differentiation of a serosa membrane seems to confirm this hypothesis. The serosa wraps the developing embryo until the first instar larva stage and invades the host tissues by microvilli projections and form a placenta like structure able to divert host resources and allowing nutrition and respiration of embryo. Such interspecific invasion, at the cellular level, recalls mammal's trophoblasts that anchors maternal uterine wall and underlines the high adaptation of A. ervi to develop in the host body.

  12. Ichneumon wasp back in favour

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    Sikkema, A.; Ramakers, P.M.J.

    2010-01-01

    The Aphidius matricariae wasp of the Ichneumon family was widely used to get rid of plant lice in greenhouse agriculture up to fifteen years ago. Since then, it has given way to its American cousin, Aphidius colemani. A comparative study by the Wageningen UR Greenhouse Horticulture group has led to

  13. Occurrence and parasitism of aphids (Hemiptera: Aphididae on cultivars of irrigated oat (Avena spp. in São Carlos, Brazil

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    Júlio Cesar Ronquim

    2004-06-01

    Full Text Available The interactions between aphids and their Hymenopteran parasitoids on irrigated oats as well as the response of different cultivars of cereals regarding the resistance to these aphids and the influence on the host/parasitoid relationships were studied during two years in São Carlos, Brazil. Rhopalosiphum padi (L. was the predominant aphid observed throughout the study, while the other species were rarely found. Five species of parasitic Hymenoptera were found: three primary parasitoids, Lysiphlebus testaceipes (Cresson, Aphidius colemani (Viereck and Diaeretiella rapae (M'Intosh and two hyperparasitoids, Syrphophagus aphidivorus (Myer and Alloxysta brassicae (Ashmead. The UPF 86081 cultivar presented significant results regarding lower Rhopalosiphum padi contamination and higher aphid parasitism rates than those observed on some other cultivars. No significant effect on the percentage variation of parasitoid emergence on the mummified aphids was observed throughout this study.Foram avaliadas as interações entre afídeos e seus himenópteros parasitóides em cultivares de aveia irrigada, como também a resposta de diferentes cultivares em relação resistência à estes afídeos e a influência nas relações hospedeiro/parasitóide durante dois anos em São Carlos, SP, Brasil. Rhopalosiphum padi (L. foi o afídeo predominante ao longo do estudo, enquanto as outras espécies raramente foram encontradas. Foram observadas cinco espécies de himenópteros parasitóides: três parasitóides primários, Lysiphlebus testaceipes (Cresson, Aphidius colemani (Viereck e Diaeretiella rapae (M'Intosh e dois hiperparasitóides, Syrphophagus aphidivorus (Myer and Alloxysta brassicae (Ashmead. A cultivar UPF 86081 apresentou resultados significativos quanto à baixa infestação por Rhopalosiphum padi e maiores taxas de parasitismo que a demais cultivares. Não foi observado efeito significativo na variação de porcentagem de emergência de parasit

  14. Relative toxicity and residual activity of insecticides used in blueberry pest management: mortality of natural enemies.

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    Roubos, Craig R; Rodriguez-Saona, Cesar; Holdcraft, Robert; Mason, Keith S; Isaacs, Rufus

    2014-02-01

    A series of bioassays were conducted to determine the relative toxicities and residual activities of insecticides labeled for use in blueberry (Vaccinium corymbosum L.) on natural enemies, to identify products with low toxicity or short duration effects on biological control agents. In total, 14 insecticides were evaluated using treated petri dishes and four commercially available natural enemies (Aphidius colemani Viereck, Orius insidiosus [Say], Chrysoperla rufilabris [Burmeister], and Hippodamia convergens [Guérin-Menéville]). Dishes were aged under greenhouse conditions for 0, 3, 7, or 14 d before introducing insects to test residual activity. Acute effects (combined mortality and knockdown) varied by insecticide, residue age, and natural enemy species. Broad-spectrum insecticides caused high mortality to all biocontrol agents, whereas products approved for use in organic agriculture had little effect. The reduced-risk insecticide acetamiprid consistently caused significant acute effects, even after aging for 14 d. Methoxyfenozide, novaluron, and chlorantraniliprole, which also are classified as reduced-risk insecticides, had low toxicity, and along with the organic products could be compatible with biological control. This study provides information to guide blueberry growers in their selection of insecticides. Further research will be needed to determine whether adoption of a pest management program based on the use of more selective insecticides will result in higher levels of biological control in blueberry.

  15. Survival of three commercially available natural enemies exposed to Michigan wildflowers.

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    Walton, Nathaniel J; Isaacs, Rufus

    2011-10-01

    Flowering plants are often used in habitat management programs to conserve the arthropod natural enemies of insect pests. In this study, nine species of flowering plants representing six families commonly found in North America east of the Rocky Mountains were evaluated based on how much they extended the lifespans of three commercially available natural enemy species in cages with cut flower stems compared with cages containing water only. The natural enemies used in the experiments were a lady beetle (Coleoptera: Coccinellidae: Hippodamia convergens Guérin-Méneville), a predatory bug (Heteroptera: Anthocoridae: Orius insidiosus (Say)), and an aphid parasitoid (Hymenoptera: Braconidae: Aphidius colemani Viereck). The plant species that most extended the lifespans of all three natural enemies were Monarda fistulosa L. (Lamiaceae), Solidago juncea Aiton (Asteraceae), and Daucus carota L. (Apiaceae). Agastache nepetoides (L.) Kuntze (Lamiaceae), Lobelia siphilitica L. (Campanulaceae), and Trifolium pratense L. (Fabaceae) were intermediate in their support of natural enemies. One plant species, Penstemon hirsutus (L.) Willdenow (Scrophulariaceae), did not contribute to the longevity of natural enemies any more than water alone. These results emphasize the need for multi-species evaluations of flowering plants for conservation biocontrol programs, and the variability in plant value for natural enemies.

  16. Repellency of Aphidius gifuensis and Pachyneuron aphidis to various odour sources%烟蚜茧蜂和蚜虫宽缘金小蜂对不同味源的趋避性

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    张英; 杨硕媛; 赵进龙; 谷星慧; 任伟; 高艳飞; 吴伟

    2012-01-01

    用“Y”型嗅觉仪观测了烟蚜茧蜂和蚜虫宽缘金小蜂对几种非寄主植物材料的趋避性.结果表明,烟蚜茧蜂对茼蒿叶的选择呈显著负趋性;蚜虫宽缘金小蜂对花椒叶、茴香叶的选择表现出明显的负趋性,但葱叶对其具有引诱作用;烟蚜茧蜂和蚜虫宽缘金小蜂混合组对薄荷叶、鱼腥草叶、紫金泽兰叶、番茄叶和姜叶的选择也表现出明显的负趋性.%Repellency of Aphidius gifuensis and Pachyneuron aphidis to several kinds of non-host plant materials was investigated with "Y" olfactometer. Results showed that Aphidius gifuensis had significant negative tropism to Chrysanthemum leaves. Pachyneuron aphidis had negative tropism to Zanthoxylum bungeanum leaves and Foeniculum vulgare leaves , but was attracted to Allium fistulosum leaves. The mixed group of Aphidius gifuensis and Pachyneuron aphidis showed negative tropism to Mentha haplocalyx leaves, Houttuynia cordata leaves, Eupatorium adenophorum leaves, Lycopersicon leaves and Ginger leaves.

  17. First report of Dolichozele koebelei Viereck, 1911 (Hymenoptera: Braconidae) on larvae of Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) in maize (Zea mays L.) under different cropping systems.

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    Silva, R B; Cruz, I; Penteado-Dias, A M

    2014-08-01

    In the context of the modern agriculture, pest control is important in order to increase productivity in maize (Zea mays L.). However, this control should be done rationally, prioritising environmentally safer methods such as biological control. This paper aims to report the occurrence of Dolichozele koebelei Viereck, 1911 (Hymenoptera: Braconidae) in Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) larvae collected in maize subjected to different cropping systems. The experiment was conducted at the Centro Nacional de Pesquisa de Milho e Sorgo (CNPMS) in Sete Lagoas, Minas Gerais State, Brazil, using organic and conventional production. Ten plants were sampled from each of the 24 plots and for each production system, three times a week during the entire cycle of maize (variety BR 106). In the laboratory, larvae were distributed in individual rearing containers with artificial diet until the end of the biological cycle. An increased number of S. frugiperda larvae was observed in organic single crop maize; hence a higher percentage of S. frugiperda larvae parasitised by Hymenoptera and Diptera also occurred in the maize under this production system. Dolichozele koebelei had not yet been described in association with larvae of S. frugiperda. The percentage of parasitism of S. frugiperda larvae was high in both experiments, indicating the importance of natural control agents in reducing the population density of S. frugiperda, and especially the importance of an appropriate crop management.

  18. First report of Dolichozele koebeleiViereck, 1911 (Hymenoptera: Braconidae on larvae of Spodoptera frugiperda (J. E. Smith, 1797 (Lepidoptera: Noctuidae in maize (Zea maysL. under different cropping systems

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    RB Silva

    Full Text Available In the context of the modern agriculture, pest control is important in order to increase productivity in maize (Zea maysL.. However, this control should be done rationally, prioritising environmentally safer methods such as biological control. This paper aims to report the occurrence of Dolichozele koebelei Viereck, 1911 (Hymenoptera: Braconidae in Spodoptera frugiperda(J. E. Smith, 1797 (Lepidoptera: Noctuidae larvae collected in maize subjected to different cropping systems. The experiment was conducted at the Centro Nacional de Pesquisa de Milho e Sorgo (CNPMS in Sete Lagoas, Minas Gerais State, Brazil, using organic and conventional production. Ten plants were sampled from each of the 24 plots and for each production system, three times a week during the entire cycle of maize (variety BR 106. In the laboratory, larvae were distributed in individual rearing containers with artificial diet until the end of the biological cycle. An increased number of S. frugiperda larvae was observed in organic single crop maize; hence a higher percentage of S. frugiperda larvae parasitised by Hymenoptera and Diptera also occurred in the maize under this production system. Dolichozele koebelei had not yet been described in association with larvae of S. frugiperda. The percentage of parasitism of S. frugiperda larvae was high in both experiments, indicating the importance of natural control agents in reducing the population density of S. frugiperda, and especially the importance of an appropriate crop management.

  19. Potential effects of plant protease inhibitors, oryzacystatin I and soybean Bowman-Birk inhibitor, on the aphid parasitoid Aphidius ervi Haliday (Hymenoptera, Braconidae).

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    Azzouz, H; Campan, E D M; Cherqui, A; Saguez, J; Couty, A; Jouanin, L; Giordanengo, P; Kaiser, L

    2005-08-01

    Protease inhibitors (PIs) have been shown to cause lethal and sublethal effects on aphids depending on the kind of PI and aphid species. Therefore, these proteins might affect aphid parasitoids directly by inhibiting their digestive proteolysis or indirectly via their development in a less suitable host. In our study, the risk of exposure and the potential effects of soybean Bowman-Birk inhibitor (SbBBI) and oryzacystatin I (OCI) on the aphid endoparasitoid Aphidius ervi were investigated using artificial diet to deliver PIs. Immunoassays showed that both SbBBI and OCI were detected in the honeydew of aphids reared on artificial diet containing these recombinant proteins at 100 microg/mL. However, only SbBBI was detected in parasitoid larvae, while this PI could not be detected in adult parasitoids emerged from PI-intoxicated aphids. Enzymatic inhibition assays showed that digestive proteolytic activity of larvae and adults of A. ervi predominantly relies on serine proteases and especially on chymotrypsin-like activity. Bioassays using SbBBI and OCI on artificial diet were performed. A. ervi that developed on intoxicated aphids had impaired fitness. Thus development and parasitism success of parasitoids exposed to OCI were severely affected. On the contrary, SbBBI only altered significantly female size and sex ratio. Direct exposure to PIs through adult food intake did not affect female's longevity, while SbBBI and OCI (100 microg/mL) induced 69% and 30% inhibition of digestive protease activity, respectively. These studies made it possible to estimate the risk of exposure to plant PIs and the sensitivity of the aphid parasitoid A. ervi to these entomotoxins, by combining immunological, biochemical and biological approaches. First it pointed out that only immature stages are affected by PIs. Secondly, it documented two different modes of effect, according to the nature of the PIs and both host and parasitoid susceptibility. OCI prevented the development of A. ervi

  20. Nonlinearities lead to qualitative differences in population dynamics of predator-prey systems.

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    Olga M C C Ameixa

    Full Text Available Since typically there are many predators feeding on most herbivores in natural communities, understanding multiple predator effects is critical for both community and applied ecology. Experiments of multiple predator effects on prey populations are extremely demanding, as the number of treatments and the amount of labour associated with these experiments increases exponentially with the number of species in question. Therefore, researchers tend to vary only presence/absence of the species and use only one (supposedly realistic combination of their numbers in experiments. However, nonlinearities in density dependence, functional responses, interactions between natural enemies etc. are typical for such systems, and nonlinear models of population dynamics generally predict qualitatively different results, if initial absolute densities of the species studied differ, even if their relative densities are maintained. Therefore, testing combinations of natural enemies without varying their densities may not be sufficient. Here we test this prediction experimentally. We show that the population dynamics of a system consisting of 2 natural enemies (aphid predator Adalia bipunctata (L., and aphid parasitoid, Aphidius colemani Viereck and their shared prey (peach aphid, Myzus persicae Sulzer are strongly affected by the absolute initial densities of the species in question. Even if their relative densities are kept constant, the natural enemy species or combination thereof that most effectively suppresses the prey may depend on the absolute initial densities used in the experiment. Future empirical studies of multiple predator - one prey interactions should therefore use a two-dimensional array of initial densities of the studied species. Varying only combinations of natural enemies without varying their densities is not sufficient and can lead to misleading results.

  1. Technical Obstacles and Solutions for Myzus persicae Control by Large-scale Reproduction of Aphidius gifuensis%规模化应用烟蚜茧蜂防治烟蚜的主要技术障碍及应对方法

    Institute of Scientific and Technical Information of China (English)

    周子方; 任伟; 周冀衡; 邓小刚; 李春明; 陈发荣; 沈晗; 孙耿

    2011-01-01

    烟蚜Myzus persicae(Sulzer)是危害烟草Nicotina tobaccum L.的一种主要害虫,烟蚜茧蜂是烟蚜的优势寄生天敌.对烟蚜茧蜂控制烟蚜能力、繁殖技术、保护应用及规模化应用中需要研究的主要技术问题进行了分析,并总结了一些可供规模化应用烟蚜茧蜂防治烟蚜的解决方案.%Myzus persicae ( Sulzer) is a major pest for Nicotina tobaccum L. , while Aphidius gifuensis Aphidiidae is the parasitic natural enemy of Myzus persicae (Sulzer). The paper analyzes gome technical problems, such as the control capacity, reproductive technology, protection and large-scale application of Aphidius gifuensis, and introduces some available solutions to the large-scale application of Aphidius gifuensis in controlling M. Persicae.

  2. Effects of volatiles from different trophic level on foraging behavior of Aphidius avenae.%不同营养层次挥发物对燕麦蚜茧蜂寄主搜寻行为的影响

    Institute of Scientific and Technical Information of China (English)

    刘勇; 胡萃; 倪汉祥; 孙京瑞

    2001-01-01

    "Y”型管嗅觉计及风洞测定试验表明,小麦植株、麦长管蚜(Sitobion avenae)、禾谷缢管蚜(Rhopalosiphum padi)对燕麦蚜茧蜂(Aphidius avenae)雌蜂的吸引作用较小,而有蚜植株及蚜害植株对其吸引作用较大,并以麦长管蚜有蚜植株的吸引作用最强.尽管该蜂对禾谷缢管蚜的寄生率极低,但由其危害诱导产生的挥发性信息化合物对该蜂仍具有较强的吸引作用.GC-MS鉴定结果表明,麦蚜取食诱导的挥发性信息化合物主要是2-莰烯、6-甲基-5-己烯-2-酮、6-甲基-5-己烯-2-醇、顺-3-己酰醋酸酯和水杨酸甲酯.其中6-甲基-5-己烯-2-酮和6-甲基-5-己烯-2-醇对燕麦蚜茧蜂的吸引作用最强,水杨酸甲酯无明显吸引作用.

  3. Health effects of predatory beneficial mites and wasps in greenhouses

    DEFF Research Database (Denmark)

    Bælum, Jesper; Enkegaard, Annie; Doekes, Gert;

    A three-year study of 579 greenhouse workers in 31 firms investigated the effect of four different beneficial arthropods. It was shown that the thrips mite Amblyseeius cucumeris and the spider mite predator Phytoseiulus persimilis may cause allergy measured by blood tests as well as eye and nose...... symptoms. No effect was seen by the predator wasp Aphidius colemani nor the predator mite Hypoaspis miles and no effect on lung diseases were seen....

  4. 20种农药对烟蚜茧蜂的急性毒性及初级风险评估%Acute Toxicity Test and Risk Evaluation of 20 Pesticides on Natural Enemies of Parasitic Wasp Aphidius gifuensis

    Institute of Scientific and Technical Information of China (English)

    于彩虹; 高然; 朱先志; 任广伟; 王振波; 瞿唯钢; 姜辉; 曲甍甍; 任晓东

    2016-01-01

    [目的]研究20种农药对烟蚜茧蜂(Aphidius gifuensis)成蜂的毒性效应,初步评估农药对该种寄生性天敌在推荐剂量暴露下的环境风险.[方法]采用药膜法测定9种杀虫剂、8种除草剂及3种杀菌剂对烟蚜茧蜂成蜂的急性毒性,并根据田间推荐剂量计算暴露量,采用风险商值HQ对杀虫剂进行风险评估.[结果]杀虫剂对烟蚜茧蜂成蜂的急性毒性较高.其中,噻虫嗪和呋虫胺有明显的触杀毒性,半数致死浓度LC50分别为1.45、1.37 mg/L,而吡蚜酮LC5o达到了518.45 mg/L.呋虫胺、噻虫嗪、丁硫克百威、丙溴磷对烟蚜茧蜂HQ值大于5.除草剂和杀菌剂在10倍田间推荐用量下,致烟蚜茧蜂的死亡率仍不到50%.[结论]呋虫胺、噻虫嗪、丁硫克百威、丙溴磷对烟蚜茧蜂存在风险,有必要继续开展高级阶段风险评估;除草剂和杀菌剂风险可接受.%[Aims] The aims were to evaluate the safety of 20 pesticides to A.gifuemis,when the acute toxicities were tested.[Methods] The acute toxicities of 9 insecticides,8 herbicides and 3 fungicides on adult parasitoids of A.gifuensis were tested under laboratory condition by the method of contacted film in glass tube.Insecticides risk was assessed with Hazard Quotient,while the recommended dose was used to calculate the exposure value.[Results] The results showed that the acute toxicities of insecticides to A.gifuensis were significantly higher than fuguicides and herbicides.Among the 9 insecticides,dinotefuran and thiamethoxam had obvious contact toxicities with median lethal concentration (LC50) of 1.45 and 1.37 mg/L,respectively,while the LC50 value ofpymetrozine was 518.45 mg/L.HQ values of dinotefuran,thiamethoxam,carbosulfan and profenofos were larger than 5.When the A.gifuensis were treated with 10 times of the field recommended dosages of herbicides and fungicides,the mortality did not reach to 50%.[Conclusions] The risks of dinotefuran,thiamethoxam,carbosulfan and

  5. Antennal Ultrastructure of Aphidius gifuensis and the Effect of Cold Storage on Antennae%烟蚜茧蜂触角的超微结构与冷藏对触角的影响

    Institute of Scientific and Technical Information of China (English)

    孙志娟; 陈丹; 范秀娟; 刘莉; 程云吉; 张长华; 任广伟; 刘向东

    2014-01-01

    【目的】明确烟蚜茧蜂(Aphidius gifuensis)触角和触角感觉器的外部形态及低温冷藏对其触角的影响,为烟蚜茧蜂的有效利用提供依据。【方法】采用扫描电镜观察正常羽化的烟蚜茧蜂雌、雄蜂触角的超微结构,比较雌、雄蜂触角感觉器的差异。将处于老熟幼虫期的烟蚜茧蜂在4℃低温下分别冷藏7、14、21和28 d,冷藏后用乙醇对样品进行脱水处理,并在扫描电镜下观察低温冷藏对烟蚜茧蜂触角外部形态及触角感觉器的影响。【结果】烟蚜茧蜂雌、雄成蜂触角外部形态相似,均属于丝状触角。雄蜂触角平均长度略长于雌蜂,雌蜂触角多为17节,雄蜂触角多为19节。成蜂触角上共有6种类型的感觉器:毛形感觉器、刺形感觉器、板形感觉器、Böhm氏鬃毛、腔锥形乳突状感觉器和锥形感觉器。毛形感觉器I主要分布在触角鞭节上,是触角上分布最广、数量最多的感觉器。板形感器主要分部在鞭节上,雄蜂从第1鞭节开始出现,雌蜂从第2鞭节开始出现。腔锥形乳突状感觉器II只存在于雄蜂触角上。雌、雄蜂感觉器的数量存在差异,雌蜂的刺形感觉器I数量多于雄蜂,雄蜂的刺形感觉器II和板形感觉器的数量则多于雌蜂。低温处理14、21、28 d后,板形感觉器、腔锥形乳突状感觉器均表现畸形,且触角最后两节分节不明显,有愈合成一节的趋势。冷藏28 d后,54%雄性触角不能正常分节,由正常情况下的19节而愈合为18节;69%的雌性触角不能正常分节,由正常情况下的17节而愈合为16节。【结论】烟蚜茧蜂触角属于丝状触角,共有6种类型感觉器。雄蜂触角长于雌蜂,感觉器的分布特点相似。低温冷藏对烟蚜茧蜂某些触角感觉器形态及触角末两节分节有显著影响。为减少冷藏对烟蚜茧蜂的伤害,应尽量避免在蛹期以前

  6. 以麦二叉蚜和麦长管蚜为寄主的烟蚜茧蜂生理生化特性比较研究%Comparative Studies of the Physiological and Biochemical Characteristics of Aphidius gifuensis Ashmead Parasitizing Schizaphis graminum and Macrosiphum avenae

    Institute of Scientific and Technical Information of China (English)

    宋修超; 郑方强; 戴凤宾; 墨铁路; 许永玉

    2012-01-01

    In the laboratory (22 ℃, RH 40%, a photoperiod of L : D=16h : 8h), the adult physiological and biochemical characteristics of Aphidius gifuensis Ashmead were compared after reared on the two species of wheat aphid, Schizaphis graminum and Macrosiphum avenae. The results showed that, compared with those reared on S. graminum, both female and male adult wasps had wider head width (0.67 mm, 0.62 mm), longer longevity (5.0 d, 4.6 d), lower supercooling points (-25.7 ℃, -25.3 ℃) and freezing points (-24.9 ℃, -24.8 ℃), and higher water, protein and carbohydrate contents when reared on M. avenae. However, there were no differences in fat content between those reared on two different host plants, and no differences in all previous parameters between female and males reared on the same host plants. There were no differences in activities of catalase, superoxide dismutase and peroxidase between those reared on two host plants, and between female and male adult wasps reared on the same host plants, with exceptions of that male adult wasps reared on M. avenae had higher activities of catalase than those reared on S. graminum and that female adult wasps reared on M. avenae had higher activities of peroxidase than those reared on S. graminum. The results indicated that A.gifuensis from M. avenae gets higher potential of anti-adversity than those from S. graminum.%在22 ℃,相对湿度 40%和光周期16L:8D条件下,对以麦二叉蚜Schizaphis graminum和麦长管蚜Macrosiphum avenae为寄主的烟蚜茧蜂Aphidius gifuensis Ashmead雌、雄成蜂生理生化特性进行了比较研究.结果发现,与以麦二叉蚜为寄主时相比,以麦长管蚜为寄主的烟蚜茧蜂雌、雄成蜂头壳更宽、寿命更长(雌蜂 5.0 d,雄蜂 4.6 d)、过冷却点(雌蜂 -25.7 ℃,雄蜂 -25.3 ℃)和结冰点(雌蜂 -24.9 ℃,雄蜂 -24.8 ℃)更低,体内水分、蛋白质和糖类含量更高,但脂肪含量无显著差异.在同一寄主上雌雄蜂间,前

  7. Consumption of snowdrop lectin (Galanthus nivalisagglutinin) causes direct effects on adult parasitic wasps.

    Science.gov (United States)

    Romeis, Jörg; Babendreier, Dirk; Wäckers, Felix L

    2003-03-01

    Honeydew is a common sugar-rich excretion of aphids and other phloem-feeding insects and represents the primary sugar in many agricultural systems. When honeydew-producing insects feed on genetically modified plants, the honeydew can contain amounts of the transgene product. Here we address whether this route of exposure poses a risk for non-target insects. Three species of parasitic wasps were selected: i.e. Aphidius colemani, Trichogramma brassicae and Cotesia glomerata, all of which are known to use honeydew as a carbohydrate source in the field. Wasps were fed sucrose solutions with varying concentrations of snowdrop lectin ( Galanthus nivalisagglutinin, GNA), a protein that has been engineered into crops to confer resistance against homopteran pests and that has been detected in honeydew. Parameters evaluated included gustatory response, longevity, fecundity, progeny emergence and sex ratio. While A. colemani and T. brassicae, but not C. glomerata, were able to detect GNA, this gustatory recognition had no effect on the acceptance of a GNA-sucrose solution. In all three species, GNA ingestion reduced parasitoid survival significantly. However, in respect to fecundity, negative effects were observed for T. brassicae but not for A. colemani. The results suggest that the effect of GNA consumption may depend on the specifics of a parasitoid's biology, especially its longevity and its mode of egg maturation.

  8. A repellent net as a new technology to protect cabbage crops.

    Science.gov (United States)

    Martin, T; Palix, R; Kamal, A; Delétré, E; Bonafos, R; Simon, S; Ngouajio, M

    2013-08-01

    Floating row covers or insect-proof nets with fine mesh are effective at protecting vegetable crops against aphids but negatively impact plant health, especially under warm conditions. Furthermore, in control of cabbage insect pests, aphid parasitoids cannot enter the fine-mesh nets, leading to frequent aphid outbreaks. To surmount these difficulties, a 40-mesh-size repellent net treated with alphacypermethrin was studied in laboratory and field tests. Results showed both irritant and repellent effects of the alphacypermethrin-treated net on Myzus persicae (Sulzer) (Hemiptera: Aphididae) and its parasitoid Aphidius colemani (Haliday) (Hymenoptera: Braconidae). Under field conditions, there were no pests on cabbage protected with the repellent net. The repellent net allowed combining a visual and repellent barrier against aphids. Because of this additive effect, repellent nets allowed covering cabbage permanently with adequate protection against all pests.

  9. Testing competing measures of profitability for mobile resources.

    Science.gov (United States)

    Barrette, Maryse; Wu, Gi-Mick; Brodeur, Jacques; Giraldeau, Luc-Alain; Boivin, Guy

    2009-01-01

    Optimal diet theory often fails to predict a forager's diet choice when prey are mobile. Because they escape or defend themselves, mobile prey are likely to increase the forager's handling time, thereby decreasing its fitness gain rate. Many animals have been shown to select their prey so as to maximize either their fitness gain or their fitness gain rate. However, no study has yet compared directly these two measures of profitability by generating testable predictions about the choice of the forager. Under laboratory conditions, we compared these two measures of profitability, using the aphid parasitoid Aphidius colemani and its host, Myzus persicae. Fitness gain was calculated for parasitoids developing in each host instar by measuring life-history traits such as developmental time, sex ratio and fecundity. Fitness gain rate was estimated by dividing fitness gain by handling time, the time required to subdue the host. Fourth instar aphids provided the best fitness gain to parasitoids, whereas second instar aphids were the most profitable in terms of fitness gain rate. Host choice tests showed that A. colemani females preferred second instar hosts, suggesting that their decision maximizes fitness gain rate over fitness gain. Our results indicate that fitness gain rate is a reliable predictor of animal's choice for foragers exploiting resources that impose additional time cost due to their mobility.

  10. Bt crops benefit natural enemies to control non-target pests.

    Science.gov (United States)

    Tian, Jun-Ce; Yao, Ju; Long, Li-Ping; Romeis, Jörg; Shelton, Anthony M

    2015-11-12

    Crops producing insecticidal crystal (Cry) proteins from Bacillus thuringiensis (Bt) control important lepidopteran pests. However, pests such as aphids not susceptible to Cry proteins may require other integrated pest management (IPM) tactics, including biological control. We fed aphids on Bt and non-Bt plants and analyzed the Bt protein residue in aphids and compared the effects of Bt plants and a pyrethroid, lambda-cyhalothrin, on the performance of three natural enemies (predators: Coleomegilla maculata and Eupeodes americanus; parasitoid Aphidius colemani) of the green peach aphid, Myzus persicae. No Bt protein residues in aphids were detected and no significant differences were recorded in the performance of pyrethroid-resistant aphids that fed on Bt broccoli expressing Cry1Ab or Cry1C, or on non-Bt broccoli plants treated or not treated with the pyrethroid. This indicated the aphids were not affected by the Cry proteins or the pyrethroid, thus removing any effect of prey quality. Tri-trophic experiments demonstrated that no C. maculata and E. americanus survived consumption of pyrethroid-treated aphids and that ovipositional behavior of A. colemani was impaired when provided with pyrethroid-treated aphids. In contrast, natural enemies were not affected when fed aphids reared on Bt broccoli, thus demonstrating the safety of these Bt plants for IPM.

  11. Spatio-Temporal Dynamics of Viruses are Differentially Affected by Parasitoids Depending on the Mode of Transmission

    Directory of Open Access Journals (Sweden)

    Elisa Viñuela

    2012-11-01

    Full Text Available Relationships between agents in multitrophic systems are complex and very specific. Insect-transmitted plant viruses are completely dependent on the behaviour and distribution patterns of their vectors. The presence of natural enemies may directly affect aphid behaviour and spread of plant viruses, as the escape response of aphids might cause a potential risk for virus dispersal. The spatio-temporal dynamics of Cucumber mosaic virus (CMV and Cucurbit aphid-borne yellows virus (CABYV, transmitted by Aphis gossypii in a non-persistent and persistent manner, respectively, were evaluated at short and long term in the presence and absence of the aphid parasitoid, Aphidius colemani. SADIE methodology was used to study the distribution patterns of both the virus and its vector, and their degree of association. Results suggested that parasitoids promoted aphid dispersion at short term, which enhanced CMV spread, though consequences of parasitism suggest potential benefits for disease control at long term. Furthermore, A. colemani significantly limited the spread and incidence of the persistent virus CABYV at long term. The impact of aphid parasitoids on the dispersal of plant viruses with different transmission modes is discussed.

  12. The endosymbiont Arsenophonus is widespread in soybean aphid, Aphis glycines, but does not provide protection from parasitoids or a fungal pathogen.

    Directory of Open Access Journals (Sweden)

    Jason A Wulff

    Full Text Available Aphids commonly harbor bacterial facultative symbionts that have a variety of effects upon their aphid hosts, including defense against hymenopteran parasitoids and fungal pathogens. The soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae, is infected with the symbiont Arsenophonus sp., which has an unknown role in its aphid host. Our research goals were to document the infection frequency and diversity of the symbiont in field-collected soybean aphids, and to determine whether Arsenophonus is defending soybean aphid against natural enemies. We performed diagnostic PCR and sequenced four Arsenophonus genes in soybean aphids from their native and introduced range to estimate infection frequency and genetic diversity, and found that Arsenophonus infection is highly prevalent and genetically uniform. To evaluate the defensive role of Arsenophonus, we cured two aphid genotypes of their natural Arsenophonus infection through ampicillin microinjection, resulting in infected and uninfected isolines within the same genetic background. These isolines were subjected to parasitoid assays using a recently introduced biological control agent, Binodoxys communis [Braconidae], a naturally recruited parasitoid, Aphelinus certus [Aphelinidae], and a commercially available biological control agent, Aphidius colemani [Braconidae]. We also assayed the effect of the common aphid fungal pathogen, Pandora neoaphidis (Remaudiere & Hennebert Humber (Entomophthorales: Entomophthoraceae, on the same aphid isolines. We did not find differences in successful parasitism for any of the parasitoid species, nor did we find differences in P. neoaphidis infection between our treatments. Our conclusion is that Arsenophonus does not defend its soybean aphid host against these major parasitoid and fungal natural enemies.

  13. The probable significance of tracheal tufts in the 8th abdominal segment of Heliothis virescens (F.) on the development of its parasitoid, Toxoneuron nigriceps (Viereck).

    Science.gov (United States)

    Rao, Asha; Henderson, Ruth E; Bradleigh Vinson, S

    2009-09-01

    The 8th abdominal segment of Heliothis virescens (Fabricius) larvae contains aerating trachea and tracheole tufts that end in the hemocoel of the 8th segment, unlike the tracheae that invade tissues in other segments. These tracheal tufts from the 8th abdominal segment extend to the tokus region, which along with the telson cavity is known to act as a "lung" for hemocytes in Calpodes ethlius and a few other lepidopteran larvae. The goal of this research was to study the effects of these tracheal tufts in the 8th abdominal segment on parasitoid development inside the host larvae, H. virescens. The first objective was to determine if the eggs of the parasitoid, Toxoneuron nigriceps, are predominantly located among the tracheal tufts of the 8th abdominal segment compared to other body cavity regions irrespective of their oviposition site or the position of the host larvae. The results showed that several hours after oviposition most of the eggs are found in the 8th abdominal segment irrespective of the oviposition site or the position of the host larvae. The second objective was to study the effect of varying oxygen concentrations in vitro on various developmental stages of the egg. The results showed that decreasing oxygen concentrations adversely affects the parasitoid egg development in vitro. A third objective was to determine the oxygen concentration in 8th abdominal segment of the host larvae and compare it to other regions of the body using an oxygen sensor placed in vivo. The results suggested relatively high concentration of oxygen in the 8th abdominal segment compared to other regions of the host, thus supporting our hypothesis that the increased oxygen level in the 8th abdominal segment is important to the development of the parasitoid eggs.

  14. Dicty_cDB: Contig-U04919-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 4 3.3 1 ( AY262783 ) Aphidius ervi clone ChileA mitochondrial cytochro... 44 3.3 1 ( AY262782 ) Aphidius erv...Aphidius ervi clone NewYork mitochondrial cytochr... 44 3.3 1 ( AY262765 ) Aphidius ervi clone ChileF mitoch

  15. A negative effect of a pathogen on its vector? A plant pathogen increases the vulnerability of its vector to attack by natural enemies.

    Science.gov (United States)

    de Oliveira, Camila F; Long, Elizabeth Y; Finke, Deborah L

    2014-04-01

    Plant pathogens that are dependent on arthropod vectors for transmission from host to host may enhance their own success by promoting vector survival and/or performance. The effect of pathogens on vectors may be direct or indirect, with indirect effects mediated by increases in host quality or reductions in the vulnerability of vectors to natural enemies. We investigated whether the bird cherry-oat aphid Rhopalosiphum padi, a vector of cereal yellow dwarf virus (CYDV) in wheat, experiences a reduction in rates of attack by the parasitoid wasp Aphidius colemani when actively harboring the plant pathogen. We manipulated the vector status of aphids (virus carrying or virus free) and evaluated the impact on the rate of attack by wasps. We found that vector status did not influence the survival or fecundity of aphids in the absence of parasitoids. However, virus-carrying aphids experienced higher rates of parasitism and greater overall population suppression by parasitoid wasps than virus-free aphids. Moreover, virus-carrying aphids were accepted as hosts by wasps more often than virus-free aphids, with a greater number of wasps stinging virus-carrying aphids following assessment by antennal palpations than virus-free aphids. Therefore, counter to the prevailing idea that persistent vector-borne pathogens enhance the performance of their vectors, we found that infectious aphids actively carrying a plant pathogen experience greater vulnerability to natural enemies. Our results suggest that parasitoids may contribute to the successful biological control of CYDV by disproportionately impacting virus-carrying vectors, and thus reducing the proportion of vectors in the population that are infectious.

  16. 蚜茧蜂对蔬菜田蚜虫的寄生功能反应%Parasitic Functional Response of Aphidius gifuensis on Aphids in Vegetable Fields

    Institute of Scientific and Technical Information of China (English)

    张升; 文静; 陈文龙; 战玉; 杨彦; 张继; 杨天沛

    2015-01-01

    To provide references for biological control of aphids in vegetable fields,the parasitic functional response of A.gifuensis on M.persicae and L.erysimi was studied.Results:A.gifuensis’s parasitic action was affected by aphid density,the parasitic amount of A.gifuensis to aphid increased with the increase of aphid density.The functional response of A.gifuensis to M.persicae and L.erysimi were fitted to Holling Ⅱ type equation.Na=0.515 3 N/(1+0.016 8 N)on M.persicae,Na=0.190 6 N/(1+0.020 4 N )on L.erysimi.The parasitic function of A.gifuensis was positively related with aphid densities,as its searching efficiency was negatively associated with aphid densities.And A.gifuensis ’s parasitic effects and searching efficiency to M.persica were all stronger than that to L.erysimi.%为了对蔬菜地蚜虫的生物防治提供参考,研究了烟蚜茧蜂对烟蚜和萝卜蚜的寄生功能反应。结果表明:烟蚜茧蜂的寄生作用受蚜虫密度影响,寄生数量随蚜虫密度的增加而增加;烟蚜茧蜂对烟蚜和萝卜蚜的寄生功能反应均符合 HollingⅡ型曲线,寄生功能反应模型分别为 Na=0.5153 N/(1+0.0168 N )和 Na=0.1906 N/(1+0.0204 N);烟蚜茧蜂对蚜虫的寄生数量与蚜虫密度呈正相关,寻找效应与蚜虫密度呈负相关,烟蚜茧蜂对烟蚜的寄生作用强于萝卜蚜。

  17. Summarize on the Using and Reproducing of Aphidius gifuensis(Aphidiidae)%烟蚜茧蜂繁殖利用概述

    Institute of Scientific and Technical Information of China (English)

    吴兴富

    2007-01-01

    烟蚜Myzus persicae(Sulzer)是为害烟草Nicotina tobaccum L.的一种主要害虫,目前生产上还是以化学杀虫剂为主控制该虫的为害.烟蚜茧蜂是烟蚜的优势寄生天敌,对烟蚜茧蜂寄主、繁殖技术和对烟蚜的控制作用及其规模化应用等方面的研究进展情况进行了概述,并对制约烟蚜茧蜂规模化繁殖利用的主要技术因素进行了探讨,以期为烟蚜茧蜂的规模化繁殖利用研究提供参考.

  18. Dicty_cDB: Contig-U15499-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available l cytoch... 40 9.9 2 ( AY262769 ) Aphidius ervi clone Japan1 mitochondrial cytochro... 40 9.9 2 ( AY262768 ) Aphidius ervi clone Germ...any mitochondrial cytochr... 40 9.9 2 ( AY262767 ) Aphidius ervi clone Israel mitoc

  19. Distinct roles of jasmonates and aldehydes in plant-defense responses.

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    E Wassim Chehab

    Full Text Available BACKGROUND: Many inducible plant-defense responses are activated by jasmonates (JAs, C(6-aldehydes, and their corresponding derivatives, produced by the two main competing branches of the oxylipin pathway, the allene oxide synthase (AOS and hydroperoxide lyase (HPL branches, respectively. In addition to competition for substrates, these branch-pathway-derived metabolites have substantial overlap in regulation of gene expression. Past experiments to define the role of C(6-aldehydes in plant defense responses were biased towards the exogenous application of the synthetic metabolites or the use of genetic manipulation of HPL expression levels in plant genotypes with intact ability to produce the competing AOS-derived metabolites. To uncouple the roles of the C(6-aldehydes and jasmonates in mediating direct and indirect plant-defense responses, we generated Arabidopsis genotypes lacking either one or both of these metabolites. These genotypes were subsequently challenged with a phloem-feeding insect (aphids: Myzus persicae, an insect herbivore (leafminers: Liriomyza trifolii, and two different necrotrophic fungal pathogens (Botrytis cinerea and Alternaria brassicicola. We also characterized the volatiles emitted by these plants upon aphid infestation or mechanical wounding and identified hexenyl acetate as the predominant compound in these volatile blends. Subsequently, we examined the signaling role of this compound in attracting the parasitoid wasp (Aphidius colemani, a natural enemy of aphids. PRINCIPAL FINDINGS: This study conclusively establishes that jasmonates and C(6-aldehydes play distinct roles in plant defense responses. The jasmonates are indispensable metabolites in mediating the activation of direct plant-defense responses, whereas the C(6-aldehyes are not. On the other hand, hexenyl acetate, an acetylated C(6-aldehyde, is the predominant wound-inducible volatile signal that mediates indirect defense responses by directing tritrophic

  20. Molecular detection and sequence analysis of wsp gene from Wolbachia in Aphidius gifuensis%烟蚜茧蜂体内Wolbachia的wsp基因分子检测及序列分析

    Institute of Scientific and Technical Information of China (English)

    赵英俄; 程加省

    2015-01-01

    采用沃尔巴克氏体(Wolbachia)的通用引物、A大组和B大组的特异性引物对烟蚜茧蜂体内Wolbachia的wsp 基因进行PCR扩增及分子检测,所获得的基因片段分别命名为wApr、wAprA和wAprB,长度分别为620 bp、566 bp 和463 bp.基因序列分析表明,wApr、wAprA和wAprB在对应位置序列仅有4个碱基的差异.系统发育分析表明,该寄生蜂仅感染了A大组的Wolbachia.

  1. Effect of Maruca vitrata (Lepidoptera: Crambidae) host plants on life-history parameters of the parasitoid Apanteles taragamae (Hymenoptera: Braconidae)

    NARCIS (Netherlands)

    Dannon, A.E.; Tamo, M.; Agboton, C.; Huis, van A.; Dicke, M.

    2012-01-01

    The effect of four host plant species of the herbivore Maruca vitrata Fabricius (Lepidoptera: Crambidae) on development time, longevity, fecundity and sex ratio of the parasitoid Apanteles taragamae Viereck (Hymenoptera: Braconidae) was investigated under laboratory conditions. The larvae were paras

  2. Revision of the new world genus Crassomicrodus Ashmead (Hymenoptera, Braconidae, Agathidinae), with an identification key to species

    Science.gov (United States)

    Figueroa, José Isaac; Sharkey, Michael Joseph; Nápoles, Jesus Romero; García, José Antonio Sánchez; Martínez, Ana Mabel; López-Martínez, Victor; Pineda, Samuel

    2011-01-01

    Abstract A key to species and descriptions are presented for 14 species of the New World genus Crassomicrodus Ashmead. Seven new species, Crassomicrodus azteca, Crassomicrodus clypealis, Crassomicrodus costaricensis, Crassomicrodus jalisciensis, Crassomicrodus mariae, Crassomicrodus oaxaquensis,and Crassomicrodus olgae are described. Crassomicrodus fenestratus (Viereck) is synonymized with Crassomicrodus nigriceps (Cresson). Crassomicrodus melanopleurus (Ashmead) is recognized as a valid species. PMID:22144862

  3. Revision of the new world genus Crassomicrodus Ashmead (Hymenoptera, Braconidae, Agathidinae, with an identification key to species

    Directory of Open Access Journals (Sweden)

    José Figueroa

    2011-10-01

    Full Text Available A key to species and descriptions are presented for 14 species of the New World genus Crassomicrodus Ashmead. Seven new species, C. azteca, C. clypealis, C. costaricensis, C. jalisciensis, C. mariae, C. oaxaquensis, and C. olgae are described. C. fenestratus (Viereck is synonymized with C. nigriceps (Cresson. C. melanopleurus (Ashmead is recognized as a valid species.

  4. Functional response and life history parameters of Apanteles taragamae, a larval parasitoid of Maruca vitrata

    NARCIS (Netherlands)

    Dannon, A.E.; Tamò, M.; Huis, van A.; Dicke, M.

    2010-01-01

    The legume pod borer Maruca vitrata Fabricius (Lepidoptera: Crambidae) is a serious pest of cowpea in West-Africa. The parasitoid Apanteles taragamae Viereck (Hymenoptera: Braconidae) that originates from Taiwan is a potential candidate for biological control of M. vitrata. We investigated under lab

  5. Assessing non-target effects and host feeding of the exotic parasitoid Apanteles taragamae, a potential biological control agent of the cowpea pod borer Maruca vitrata

    NARCIS (Netherlands)

    Dannon, A.E.; Tamo, M.; Huis, van A.; Dicke, M.

    2012-01-01

    Apanteles taragamae Viereck is a larval parasitoid introduced in Benin for classical biological control of the cowpea pod borer Maruca vitrata Fabricius. In the laboratory, we evaluated the effects of A. taragamae on non-target herbivore species, and on another parasitoid of M. vitrata, i.e. the egg

  6. On the German Language in America.

    Science.gov (United States)

    Lewis, Brian A.

    Sociolinguistic patterns among German immigrants to the United States of America are examined in this paper. Earlier studies in this area, including Wolfgang Viereck's work published in "Orbis" in 1967 and 1968, are examined. Through an analysis of the immigration patterns of the citizens of Glarus, Switzerland, in 1845 to New Glarus,…

  7. Impact of change in winter strategy of one parasitoid species on the diversity and function of a guild of parasitoids.

    Science.gov (United States)

    Andrade, Thiago Oliveira; Krespi, Liliane; Bonnardot, Valérie; van Baaren, Joan; Outreman, Yannick

    2016-03-01

    The rise of temperatures may enable species to increase their activities during winter periods and to occupy new areas. In winter, resource density is low for most species and an increased number of active consumers during this season may produce heightened competitive pressure. In Western France, the aphid parasitoid species Aphidius avenae Haliday has been known to adopt a winter diapausing strategy adjacent to newly sown cereal crops, until recent reports of active winter populations in cereal crops. We investigate how the addition of this species to the winter guild of parasitoids may change the structure of the aphid-parasitoid food web and the host-exploitation strategies of previously occurring parasitoids. We showed that in winter, Aphidius avenae was mostly associated with two aphid species, Sitobion avenae Fabricius and Metopolophium dirhodum Walker, while the generalist species Aphidius rhopalosiphi was restricted to the aphid species Rhopalosiphum padi L. in the presence of Aphidius avenae. Due to this new competition, winter food webs present a higher degree of compartmentalization and lower proportional similarity index values than spring ones. Parasitoid and aphid abundances responded significantly to changes in daily high temperatures, suggesting that the host-parasitoid community structure can be partly predicted by climate. This study demonstrates how a change in the winter strategy of one species of a guild can modify complex interspecific relationships in host-parasitoid systems.

  8. The Braconidae (Hymenoptera) of Greenland

    NARCIS (Netherlands)

    Achterberg, van C.

    2006-01-01

    Thirty species belonging to 16 genera of the family Braconidae (Hymenoptera) are reported from Greenland. Seven are new species described and illustrated below: Dacnusa groenlandica spec. nov.; Aphidius tarsalis spec. nov.; Praon brevistigma spec. nov.; Blacus (B.) groenlandicus spec. nov.; Cotesia

  9. Environmental Assessment for the Construction of Power and Fiber Optic Lines to Facilities in the Yukon Training Area, Alaska-Phase 3

    Science.gov (United States)

    2006-07-01

    feather moss. Closed canopy black spruce forest tends to return to its original composition after fire (Viereck et al., 1992). In the absence of fire...facility, the vegetation becomes a more open growth of mixed spruce and hardwoods, with it eventually getting to an alpine tundra vegetative community...area. Non migratory birds include ravens, jays, chickadees, songbirds, woodpeckers, grouse, and ptarmigan. Raptors include bald and golden eagles, hawks

  10. Native bee diversity and pollen foraging specificity in cultivated highbush blueberry (Ericaceae: Vaccinium corymbosum) in Rhode Island

    Science.gov (United States)

    Scott, Zachary; Ginsberg, Howard; Alm, Steven R.

    2016-01-01

    We identified 41 species of native bees from a total of 1,083 specimens collected at cultivated highbush blueberry plantings throughout Rhode Island in 2014 and 2015. Andrena spp., Bombus spp., and Xylocopa virginica (L.) were collected most often. Bombus griseocollis (DeGeer), B. impatiens Cresson, B. bimaculatus Cresson, B. perplexus Cresson, and Andrena vicina Smith collected the largest mean numbers of blueberry pollen tetrads. The largest mean percent blueberry pollen loads were carried by the miner bees Andrena bradleyi Viereck (91%), A. carolina Viereck (90%), and Colletes validus Cresson (87%). The largest mean total pollen grain loads were carried by B. griseocollis (549,844), B. impatiens (389,558), X. virginica (233,500), and B. bimaculatus (193,132). Xylocopa virginica was the fourth and fifth most commonly collected bee species in 2014 and 2015, respectively. They exhibit nectar robbing and females carried relatively low blueberry pollen loads (mean 33%). Overall, we found 10 species of bees to be the primary pollinators of blueberries in Rhode Island.

  11. Parasitóides (Hymenoptera: Braconidae de Anastrepha Schiner (Diptera: Tephritidae no estado do Acre Parasitoids (Hymenoptera: Braconidae of Anastrepha Schiner (Diptera: Tephritidae in the state of Acre, Brazil

    Directory of Open Access Journals (Sweden)

    Marcílio José Thomazini

    2009-03-01

    Full Text Available Este trabalho relata a primeira ocorrência de parasitóides em moscas-das-frutas do gênero Anastrepha Schiner no estado do Acre. No município de Bujari foram encontrados os braconídeos Opius bellus Gahan (72,5%, Doryctobracon areolatus (Szépligeti (26,8% e Utetes anastrephae (Viereck (0,7% associados a A. obliqua (Macquart em frutos de taperebá (Spondias mombin L., com parasitismo de 29,5%. No município de Rio Branco, em frutos de goiaba (Psidium guajava L., ocorreu somente D. areolatus em A. obliqua com parasitismo de 2,7%.This paper records the first parasitoids occurrence on Anastrepha Schiner fruit flies in the state of Acre, Brazil. In the Bujari County there occurred the braconids Opius bellus Gahan (72.5%, Doryctobracon areolatus (Szépligeti (26.8% e Utetes anastrephae (Viereck (0.7% associated with A. obliqua (Macquart in tapereba fruits (Spondias mombin L., with parasitism of 29.5%. In guajava fruits (Psidium guajava L. at Rio Branco County, only D. areolatus on A. obliqua occurred, with parasitism of 2.7%.

  12. 早熟素对棉铃虫滞育的终止作用%TERMINATION OF PUPAL DIAPAUSE IN THE BOLLWORM HELICOVERPA ARMIGERA BY PRECOCENE Ⅱ

    Institute of Scientific and Technical Information of China (English)

    王方海; 龚和

    2001-01-01

    用外源激素和某些化合物处理棉铃虫的滞育蛹,结果发现早熟素与蜕皮素-样可终止棉铃虫蛹的滞育,使其进入到发育阶段.而保幼激素类似物ZR-515,环腺氨酸(cAMP)和色氨类化合物(5-HT)则完全不具有终止棉铃虫滞育的作用.结合早熟素还可终止蚜虫寄生蜂Aphidius matricariae Haliday和Praon volucre Haliday的预蛹滞育的报道,建议早熟素应具有终止多种类昆虫滞育的功能.%Precocene Ⅱ terminated pupal diapause in the bollworm Helicoverpa armigera as 20-hydroxyecdysterone did, whereas juvenile hormone analog ZR-515, cyclic adenosine monophosphate (cAMP), and 5-hydroxytryptamine (5-HT) did not. The results indicate that precocene Ⅱ affects diapausing pupae in the similar way as what was found in the prepupae of the aphid parasitoids, Aphidius matricariae Haliday and Praon volucre Haliday (Hymenoptera: Aphidiidae). It is suggested that precocene Ⅱ may affect different kinds of termination of diapause in insects.

  13. Parasitóides associados às moscas-das-frutas (Diptera: Tephritoidea em café orgânico com e sem arborização em Valença, RJ, Brasil Parasitoids associated with fruit flies (Diptera: Tephritoidea in organic coffee plantation under shaded and unshaded management in Valença, RJ, Brazil

    Directory of Open Access Journals (Sweden)

    Elen de Lima Aguiar-Menezes

    2008-12-01

    Full Text Available Objetivou-se, com esse trabalho, determinar as espécies de parasitóides associados às moscas-das-frutas infestando seis cultivares de café arábica (Coffea arabica L., em sistema de cultivo com e sem arborização, sob manejo orgânico. Uma amostra de 1 kg de frutos maduros por cultivar foi colhida em maio de 2005. Os frutos foram depositados em bandejas plásticas, contendo uma camada de areia, a qual serviu como substrato para a fase de pupa. Os pupários foram quantificados e mantidos em copos plásticos transparentes com areia até a emergência dos insetos. Sete espécies de parasitóides da ordem Hymenoptera foram identificadas, das quais cinco da família Braconidae: Asobara anastrephae (Muesebeck, Doryctobracon areolatus (Szépligeti, Utetes anastrephae (Viereck, Opius bellus Gahan e Opius sp., e duas da Figitidae: Aganaspis pelleranoi (Brèthes e Lopheucoila anastrephae Weld. Larvas de Tephritidae e Lonchaeidae infestando frutos dos seis cultivares foram parasitadas por Braconidae e Figitidae, com média de 14,2% e 7,7% nos sistemas sem e com arborização, respectivamente.The aim of this work was to determine the parasitoid species associated with fruit flies infesting six cultivars of arabic coffee under shaded and unshaded organic management. A 1kg-sample of maturing fruits per cultivar was harvested in May 2005. The fruits were placed in plastic trays containing a layer of thin sand, as a substrate for pupa phase. The puparia were quantified and kept in transparent plastic cups with sand until the emergence of the insects. Seven parasitoid species of the order Hymenoptera were identified, from which five belong to the family Braconidae: Asobara anastrephae (Muesebeck, Doryctobracon areolatus (Szépligeti, Utetes anastrephae (Viereck, Opius bellus Gahan and Opius sp., and two of the Figitidae: Aganaspis pelleranoi (Brèthes and Lopheucoila anastrephae Weld. Larvae of Tephritidae and Lonchaeidae infesting fruits of the six

  14. Longevity of multiple species of tephritid (Diptera) fruit fly parasitoids (Hymenoptera: Braconidae: Opiinae) provided exotic and sympatric-fruit based diets.

    Science.gov (United States)

    Stuhl, Charles; Cicero, Lizette; Sivinski, John; Teal, Peter; Lapointe, Stephen; Paranhos, Beatriz Jordão; Aluja, Martín

    2011-11-01

    While adult parasitic Hymenoptera in general feed on floral and extrafloral nectars, hemipteran-honeydews and fluids from punctured hosts, Diachasmimorpha longicaudata (Ashmead), an Old World opiine braconid introduced to tropical/subtropical America for the biological control of Anastrepha spp. (Tephritidae), can survive on fruit juices as they seep from injured fruit. An ability to exploit fruit juice would allow such a parasitoid to efficiently forage for hosts and food sources simultaneously. Two New World opiines, Doryctobracon areolatus (Szepligeti) and Utetes anastrephae (Viereck), are also prominent Anastrepha parasitoids and are roughly sympatric. All three species were provided with: (1) pulp and juice diets derived from a highly domesticated Old World fruit (orange, Citrus sinensis L.) that is only recently sympatric with the Mexican flies and parasitoids and so offered little opportunity for the evolution of feeding-adaptations and (2) a less-domesticated New World fruit (guava, Psidium guajava L.), sympatric over evolutionary time with D. areolatus and U. anastrephae. Both sexes of D. longicaudata died when provided guava pulp or juice at a rate similar to a water-only control. D. areolatus and U. anastrephae, presumably adapted to the nutrient/chemical constituents of guava, also died at a similar rate. Survival of all three species on orange pulp and juice was greater than on water, and often equaled that obtained on a honey and water solution. In confirmatory experiments in Mexico, D. areolatus and U. anastrephae, as well as other tephritid parasitoids Doryctobracon crawfordi (Viereck) and Opius hirtus (Fisher), all died at a significantly higher rates when provided guava in comparison to a honey and water diet. Such a result is likely due to guavas being repellent, innutritious or toxic. D. longicaudata clearly consumed guava juice tagged with a colored dye. Dilutions of orange and guava juice resulted in shorter lifespans than dilutions of orange

  15. Systemic Imidacloprid Affects Intraguild Parasitoids Differently.

    Directory of Open Access Journals (Sweden)

    Sally V Taylor

    Full Text Available Toxoneuron nigriceps (Viereck (Hymenoptera, Braconidae and Campoletis sonorensis (Cameron (Hymenoptera, Ichneumonidae are solitary endoparasitoids of the tobacco budworm, Heliothis virescens (Fabricius (Lepidoptera, Noctuidae. They provide biological control of H. virescens populations in Southeastern US agricultural production systems. Field and greenhouse experiments conducted from 2011-2014 compared parasitism rates of parasitoids that developed inside H. virescens larvae fed on tobacco plants treated with and without imidacloprid. The parasitoids in our study did not have a similar response. Toxoneuron nigriceps had reduced parasitism rates, but parasitism rates of C. sonorensis were unaffected. Preliminary data indicate that adult female lifespans of T. nigriceps are also reduced. ELISA was used to measure concentrations of neonicotinoids, imidacloprid and imidacloprid metabolites in H. virescens larvae that fed on imidacloprid-treated plants and in the parasitoids that fed on these larvae. Concentrations were detectable in the whole bodies of parasitized H. virescens larvae, T. nigriceps larvae and T. nigriceps adults, but not in C. sonorensis larvae and adults. These findings suggest that there are effects of imidacloprid on multiple trophic levels, and that insecticide use may differentially affect natural enemies with similar feeding niches.

  16. Systemic Imidacloprid Affects Intraguild Parasitoids Differently.

    Science.gov (United States)

    Taylor, Sally V; Burrack, Hannah J; Roe, R Michael; Bacheler, Jack S; Sorenson, Clyde E

    2015-01-01

    Toxoneuron nigriceps (Viereck) (Hymenoptera, Braconidae) and Campoletis sonorensis (Cameron) (Hymenoptera, Ichneumonidae) are solitary endoparasitoids of the tobacco budworm, Heliothis virescens (Fabricius) (Lepidoptera, Noctuidae). They provide biological control of H. virescens populations in Southeastern US agricultural production systems. Field and greenhouse experiments conducted from 2011-2014 compared parasitism rates of parasitoids that developed inside H. virescens larvae fed on tobacco plants treated with and without imidacloprid. The parasitoids in our study did not have a similar response. Toxoneuron nigriceps had reduced parasitism rates, but parasitism rates of C. sonorensis were unaffected. Preliminary data indicate that adult female lifespans of T. nigriceps are also reduced. ELISA was used to measure concentrations of neonicotinoids, imidacloprid and imidacloprid metabolites in H. virescens larvae that fed on imidacloprid-treated plants and in the parasitoids that fed on these larvae. Concentrations were detectable in the whole bodies of parasitized H. virescens larvae, T. nigriceps larvae and T. nigriceps adults, but not in C. sonorensis larvae and adults. These findings suggest that there are effects of imidacloprid on multiple trophic levels, and that insecticide use may differentially affect natural enemies with similar feeding niches.

  17. Larval endoparasitoids (Hymenoptera of frugivorous flies (Diptera, Tephritoidea reared from fruits of the cerrado of the State of Mato Grosso do Sul , Brazil

    Directory of Open Access Journals (Sweden)

    Manoel A. Uchôa-Fernandes

    2003-01-01

    Full Text Available This paper presents a five years survey of endoparasitoids obtained from the larvae of frugivorous Tephritidae and Lonchaeidae flies. The insects were reared from cultivated and wild fruits collected in areas of the cerrado in the State of Mato Grosso do Sul, Brazil. The flies obtained from 14 host fruit species were eight Anastrepha species, Ceratitis capitata (Wiedemann, 1824 (Tephritidae; Dasiops sp. and Neosilba spp. (Lonchaeidae. Eleven parasitoid species were collected: Braconidae - Asobara anastrephae (Muesebek, 1958, Doryctobracon areolatus (Szépligeti, 1911, D. fluminensis (Costa Lima, 1938, Opius bellus Gahan, 1930 and Utetes anastrephae (Viereck, 1913; Figitidae - Aganaspis nordlanderi Wharton, 1998, Lopheucoila anastrephae (Rhower, 1919, Odontosema anastrephae (Borgmeier, 1935 and Trybliographa infuscata Gallardo, Díaz & Uchôa-Fernandes, 2000 and, Pteromalidae - Spalangia gemina Boucek, 1963 and S. endius Walker, 1839. In all cases only one parasitoid emerged per puparium. D. areolatus was the most abundant and frequent parasitoid of fruit fly species, as was L. anastrephae in Neosilba spp. larvae. This is the first record of A. nordlanderi in the midwestern Brazilian region.

  18. Determination of Opiinae parasitoids (Hymenoptera: Braconidae) associated with crop infesting Bactrocera spp. (Diptera: Tephritidae) using COI and Cyt b sequences

    Science.gov (United States)

    Shariff, Safiah; Yaakop, Salmah; Zain, Badrul Munir Md.

    2013-11-01

    Members of the Opiinae subfamily (Hymenoptera: Braconidae) are well known as important parasitoids of fruit fly larvae (Diptera: Tephritidae). They are widely used as biological control agents of fruit flies, especially the Bactrocera Macquart species that infest fruits. In this study, the larvae of fruit flies were collected from infested crops including star fruit, guava, wax apple and ridge gourd. The parasitized larvae were then reared under laboratory conditions until emergence of the adult parasitoids. Additionally, Malaise trap also was used to collect parasitoid species. The general concept of the multiplex PCR has been performed is to amplify two mitochondrial DNA markers, namely cytochrome oxidase subunit I (COI) and cytochrome b (Cyt b) simultaneously. Therefore, the lengthy process of reaction will be reduced. The status of the fruit fly species has also been confirmed by using COI marker on the early stage of the larvae. Maximum parsimony (MP) and Bayesian Inference (BI) were implemented to help and support the identification of Opiinae species. The result obtained from this study showed three parasitoid genera of the Opiinae viz. Fopius Wharton, Psyttalia Walker and Diachasmimorpha Viereck. Each genus has been determined by clustering together in a similar clade according to their infested crops. Therefore, accurate determination of parasitoids and the fruit fries species was highly useful and necessary for successful biological control of Bactrocera species.

  19. Mexican Fruit Fly Populations in the Semi-Arid Highlands of the Sierra Madre Oriental in Northeastern Mexico.

    Science.gov (United States)

    Vanoye-Eligio, V; Mora-Olivo, A; Gaona-García, G; Reyes-Zepeda, F; Rocandio-Rodríguez, M

    2017-01-04

    The Mexican fruit fly, Anastrepha ludens Loew (Diptera: Tephritidae), is one of the most important pests of citrus in Mexico. We report the results of an analysis of A. ludens populations that inhabit the semi-arid highlands of the Sierra Madre Oriental in northeastern Mexico. This study aimed to provide information on population fluctuation of A. ludens and how it relates to climate variables, as well as insights into habitat and native parasitoids. Population peaked in the period July-November when ripe fruits of the wild host, Casimiroa pubescens Ramírez, were available. No adults were captured the rest of the year, suggesting that high populations depend on the availability of wild host fruit. No significant relationships between population fluctuation and climatic variables were observed, except for minimum temperature. Fruit samples of citron (Citrus medica L.), pomegranate (Punica granatum L.), and C. pubescens were collected to determine degree of infestation. Infestation levels (pupae/g) ranged between 0.0006 for citron, 0.0047 for pomegranate, and 0.0240 for C. pubescens. A native parasitoid of Tephritidae, Doryctobracon crawfordii (Viereck) (Braconidae), was identified. Parasitism percentage was calculated at 12.5% on C. pubescens fruits. No parasitoids were observed on citron or pomegranate fruit samples. These results contribute to knowledge on behavior of A. ludens native to temperate environments where no commercial hosts are available. Further research on host expansion of this pest in light of scenarios of global climate change is suggested.

  20. 烟蚜茧蜂规模化繁殖和释放技术研究

    Institute of Scientific and Technical Information of China (English)

    王树会; 魏佳宁

    2006-01-01

    烟蚜(桃蚜)Myzus persicaeSulzer是危害云南省烟草Nicotina tobaccumL.的一种主要害虫.生产中还是以杀虫剂为主控制该虫危害.然而,近年来地方政府、科技人员和农户都在寻求以生物防治的方法控制烟蚜危害.烟蚜茧蜂是自然界控制烟蚜的一种优势天敌.作者在云南省玉溪烟区经过5 a的研究和推广,形成的烟蚜茧蜂(Aphidius gifuensisAshmead)大规模繁殖和释放技术.对大量繁蜂的设备和成本核算以及相关的一些技术问题进行了一定的探讨.

  1. Characterization of the natural enemy community attacking cotton aphid in the Bt cotton ecosystem in Northern China.

    Science.gov (United States)

    Ali, Abid; Desneux, Nicolas; Lu, Yanhui; Liu, Bing; Wu, Kongming

    2016-04-14

    Planting Bt cotton in China since 1997 has led to important changes in the natural enemy communities occurring in cotton, however their specific effect on suppressing the cotton aphids (being notorious in conventional cotton ecosystem) has not been fully documented yet. We observed strong evidence for top-down control of the aphid population, e.g. the control efficiency of natural enemies on cotton aphid increased significantly in open field cages compared to exclusion cages, accounted for 60.2, 87.2 and 76.7% in 2011, 2012 and 2013 season, respectively. The cotton aphid populations peaked in early June to late July (early and middle growth stages) in open field cotton survey from 2011 to 2013. The population densities of cotton aphids and natural enemies were highest on middle growth stage while lowest densities were recorded on late stage for aphids and on early plant stage for natural enemies. Aphid parasitoids (Trioxys spp., Aphidius gifuensis), coccinellids and spiders were key natural enemies of cotton aphid. Briefly, natural enemies can suppress aphid population increase from early to middle plant growth stages by providing biocontrol services in Chinese Bt cotton.

  2. Mechanisms for stable coexistence in an insect community.

    Science.gov (United States)

    Fan, Meng; Zhang, Bingbing; Li, Michael Yi

    2010-07-01

    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 coexistence in a three-species community in which any two species alone do not co-exist. More specifically, it is known that, when a predator is introduced into a community of two competing species, if the predator only predates on the strong competitor, it can allow the weak competitor to survive, but may drive the strong competitor to extinction through over-exploitation. We show that if the weak competitor interferes the predation on the strong competitor through trait-mediated indirect effects, then all three species can stably co-exist.

  3. Relações interespecíficas entre parasitoides nativos de moscas-das-frutas e o braconídeo exótico Diachasmimorpha longicaudata em frutos de 'umbu-cajá' Interespecific relations between native parasitoids of fruit flies and exotic braconid Diachasmimorpha longicaudata in fruits of 'umbu-cajá'

    Directory of Open Access Journals (Sweden)

    Zuzinaide Vidal Bomfim

    2010-02-01

    Full Text Available Espécies de vespas parasitoides (Hymenoptera: Braconidae são importantes agentes de controle biológico de moscas-das-frutas (Diptera: Tephritidae. Este trabalho teve por objetivo conhecer os efeitos da liberação e as relações de competitividade interespecífica do parasitoide exótico Diachasmimorpha longicaudata Ashmead sobre o complexo de parasitoides nativos de moscas-das-frutas associado a frutos de 'umbu-cajá' (Spondias spp. na região do Recôncavo Baiano. Entre os meses de abril e julho de 2006, 8.955 frutos (192,93kg foram coletados antes e após (24 e 48 horas a liberação de 9.600 fêmeas de D. longicaudata em campo. Obteve-se um total de 8.724 pupários de Tephritidae, dos quais emergiram 3.963 adultos de Anastrepha obliqua (Macquart e 1.115 parasitoides. A maior frequência relativa foi de Doryctobracon areolatus (Szépligeti, seguida por Asobara Anastrephae (Muesebeck e Utetes Anastrephae (Viereck. Após 24 e 48 horas da liberação do parasitoide exótico D. longicaudata em campo, constatou-se que o índice de parasitismo total aumentou de 15,86 para 20,4 e 45,19%, respectivamente. Assim, observou-se que a liberação da espécie exótica D. longicaudata não apresenta efeitos negativos na ocorrência dos parasitoides nativos e contribui para complementar o controle biológico natural de A. obliqua em frutos de 'umbu-cajá', nas condições deste estudo.Wasps parasitoid species (Hymenoptera: Braconidae are fruit flies (Diptera: Tephritidae biological control important agents. This study aimed to know the effects of the release and interspecific competitive relationships of the exotic parasitoid Diachasmimorpha longicaudata Ashmead (Hymenoptera: Braconidae on the native parasitoid complex of fruit flies in Spondias spp. in the region of Recôncavo Baiano. From April to July of 2006, 8.955 fruits (192.93kg were collected before and after (24 and 48 hours release of 9.600 females of D. longicaudata. Exactly 8.724 Tephritidae

  4. Diversity and seasonality of fruit flies (Diptera: Tephritidae and Lonchaeidae and their parasitoids (Hymenoptera: Braconidae and Figitidae in orchards of guava, loquat and peach

    Directory of Open Access Journals (Sweden)

    MF. Souza-Filho

    Full Text Available This work was carried out in orchards of guava progenies, and loquat and peach cultivars, in Monte Alegre do Sul, SP, Brazil, in 2002 and 2003. Guavas and loquats were bagged and unbagged bi-weekly and weekly, respectively, for assessment of the infestation period. Peach was only bagged weekly. The assays started when the fruits were at the beginning of development, but still green. Ripe fruits were taken to the laboratory and placed individually into plastic cups. McPhail plastic traps containing torula yeast were hung from January 2002 to January 2004 to assess the fruit fly population in each orchard, but only the Ceratitis capitata population is here discussed. Five tephritid species were reared from the fruits: Anastrepha bistrigata Bezzi, A. fraterculus (Wiedemann, A. obliqua (Macquart, A. sororcula Zucchi, and C. capitata, in addition to six lonchaeid species: Neosilba certa (Walker, N. glaberrima (Wiedemann, N. pendula (Bezzi, N. zadolicha McAlpine and Steyskal, Neosilba sp. 4, and Neosilba sp. 10 (both species are in the process of being described by P. C. Strikis, as well as some unidentified Neosilba species. Ten parasitoid species were obtained from fruit fly puparia, of which five were braconids: Asobara anastrephae (Muesebeck, Doryctobracon areolatus (Szépligeti, D. brasiliensis (Szépligeti, Opius bellus Gahan, and Utetes anastrephae (Viereck, and five figitids: Aganaspis pelleranoi (Brèthes, Dicerataspis grenadensis Ashmead, Lopheucoila anastrephae (Rhower, Leptopilina boulardi (Barbotin, Carlton and Kelner-Pillaut, and Trybliographa infuscata Diaz, Gallardo and Uchôa. Ceratitis capitata showed a seasonal behavior with population density peaking at the second semester of each year. Anastrepha and Neosilba species remained in the orchards throughout both years.

  5. Effect of selected insecticides on the natural enemies Coleomegilla maculata and Hippodamia convergens (Coleoptera: Coccinellidae), Geocoris punctipes (Hemiptera: Lygaeidae), and Bracon mellitor, Cardiochiles nigriceps, and Cotesia marginiventris (Hymenoptera: Braconidae) in cotton.

    Science.gov (United States)

    Tillman, P G; Mulrooney, J E

    2000-12-01

    We evaluated the toxicity of three insecticides (lambda cyhalothrin, spinosad, and S-1812) to the natural enemies Bracon mellitor Say, Cardiochiles nigriceps Viereck, Coleomegilla maculata De Geer, Cotesia marginiventris (Cresson), Geocoris punctipes (Say), and Hippodamia convergens Guérin-Méneville, in topical, residual, and field assays. Lambda cyhalothrin exhibited the greatest toxicity to the natural enemies. In topical toxicity tests, lambda cyhalothrin adversely affected each natural enemy species studied. Residues of lambda cyhalothrin on cotton leaves were toxic to B. mellitor, C. nigriceps, C. maculata, and C. punctipes. Interestingly, residues of this insecticide were not very toxic to C. marginiventris and H. convergens. Geocoris punctipes and C. maculata numbers in the field generally were significantly lower for lambda cyhalothrin treatments than for the other four treatments, substantiating the previous tests. Although cotton aphids began to increase over all treatments around the middle of the test period, the number of cotton aphids in the lambda cyhalothrin plots was significantly higher than the number in any of the other treatments. As cotton aphids increased in lambda cyhalothrin field plots, the predator H. convergens also increased in number, indicating that lambda cyhalothrin did not adversely affect it in accordance with the residual tests. Spinosad exhibited marginal to excellent selectivity, but was highly toxic to each parasitoid species and G. punctipes in topical toxicity tests and to B. mellitor in residual tests. Spinosad generally did not affect the number of G. punctipes, H. convergens, and C. maculata in the field except for one day after the second application for G. punctipes. S-1812 exhibited good to excellent selectivity to the natural enemies. Some reduction of G. punctipes occurred for only a short period after the first and second application of this insecticide in the field. H. convergens and C. maculata were affected

  6. Effect of Maruca vitrata (Lepidoptera: Crambidae) host plants on life-history parameters of the parasitoid Apanteles taragamae (Hymenoptera: Braconidae)

    Institute of Scientific and Technical Information of China (English)

    Elie A.Dannon; Manuele Tamò; Cyriaque Agboton; Arnold van Huis; Marcel Dicke

    2012-01-01

    The effect of four host plant species of the herbivore Maruca vitrata Fabricius (Lepidoptera:Crambidae) on development time,longevity,fecundity and sex ratio of the parasitoid Apanteles taragamae Viereck (Hymenoptera:Braconidae) was investigated under laboratory conditions.The larvae were parasitized when in the second instar.Maruca vitrata larvae were fed with flowers of four legumes,that is,Vigna unguiculata (cowpea),Sesbania rostrata,Lonchocarpus sericeus and Pterocarpus santalinoides,or an artificial diet both before and after parasitization.The parasitoid did not develop in hosts feeding on L.sericeus or V.unguiculata at 25℃,or on P.santalinoides at 25℃ or 29℃.Apanteles taragaraae had the shortest development time on artificial diet at both 25℃ and 29℃ while the longest development time was recorded on L.sericeus at 29℃.Female wasps took longer to develop compared to males at the two temperatures,regardless of the feeding substrate of their host.The longevity of the wasps at 25℃ varied among feeding substrates,but not at 29℃.Survival rate of parasitized larvae depends on the feeding substrate.Moreover,infection of host larvae with Maruca vitrata multi-nucleopolyhedrovirus (MaviMNPV) killed larger proportions of parasitized larvae at 25℃ than at 29℃,which was likely caused by the difference in parasitoid developmental rate.The proportion of female parasitoids was lowest on L.sericeus.The daily fecundity showed a nonlinear trend regardless of the feeding substrate,indicating that A.taragaraae is a pro-ovigenic species.The data support the slow growth-high mortality hypothesis.

  7. Diversity and seasonality of fruit flies (Diptera: Tephritidae and Lonchaeidae) and their parasitoids (Hymenoptera: Braconidae and Figitidae) in orchards of guava, loquat and peach

    Energy Technology Data Exchange (ETDEWEB)

    Souza-Filho, M.F.; Raga, A. [Instituto Biologico, Campinas, SP (Brazil)], e-mail: miguelf@biologico.sp.gov.br; Azevedo-Filho, J.A. [Agencia Paulista de Tecnologia dos Agronegocios (APTA), Monte Alegre do Sul, SP (Brazil). Polo Regional do Leste Paulista; Strikis, P.C. [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Inst. de Biologia. Dept. de Parasitologia; Guimaraes, J.A. [EMBRAPA Agroindustria Tropical, Fortaleza, CE (Brazil); Zucchi, R.A. [Escola Superior de Agricultura Luiz de Queiroz (ESALQ/USP), Piracicaba, SP (Brazil). Dept. de Entomologia, Fitopatologia e Zoologia Agricola

    2009-02-15

    This work was carried out in orchards of guava progenies, and loquat and peach cultivars, in Monte Alegre do Sul, SP, Brazil, in 2002 and 2003. Guavas and loquats were bagged and unbagged bi-weekly and weekly, respectively, for assessment of the infestation period. Peach was only bagged weekly. The assays started when the fruits were at the beginning of development, but still green. Ripe fruits were taken to the laboratory and placed individually into plastic cups. McPhail plastic traps containing torula yeast were hung from January 2002 to January 2004 to assess the fruit fly population in each orchard, but only the Ceratitis capitata population is here discussed. Five tephritid species were reared from the fruits: Anastrepha bistrigata Bezzi, A. fraterculus (Wiedemann), A. obliqua (Macquart), A. sororcula Zucchi, and C. capitata, in addition to six lonchaeid species: Neosilba certa (Walker), N. glaberrima (Wiedemann), N. pendula (Bezzi), N. zadolicha McAlpine and Steyskal, Neosilba sp. 4, and Neosilba sp. 10 (both species are in the process of being described by P. C. Strikis), as well as some unidentified Neosilba species. Ten parasitoid species were obtained from fruit fly puparia, of which five were braconids: Asobara anastrephae (Muesebeck), Doryctobracon areolatus (Szepligeti), D. brasiliensis (Szepligeti), Opius bellus Gahan, and Utetes anastrephae (Viereck), and five figitids: Aganaspis pelleranoi (Brethes), Dicerataspis grenadensis Ashmead, Lopheucoila anastrephae (Rhower), Leptopilina boulardi (Barbotin, Carlton and Kelner-Pillaut), and Trybliographa infuscata Diaz, Gallardo and Uchoa. Ceratitis capitata showed a seasonal behavior with population density peaking at the second semester of each year. Anastrepha and Neosilba species remained in the orchards throughout both years. (author)

  8. Influence of temperature on patch residence time in parasitoids: physiological and behavioural mechanisms.

    Science.gov (United States)

    Moiroux, Joffrey; Abram, Paul K; Louâpre, Philippe; Barrette, Maryse; Brodeur, Jacques; Boivin, Guy

    2016-04-01

    Patch time allocation has received much attention in the context of optimal foraging theory, including the effect of environmental variables. We investigated the direct role of temperature on patch time allocation by parasitoids through physiological and behavioural mechanisms and its indirect role via changes in sex allocation and behavioural defences of the hosts. We compared the influence of foraging temperature on patch residence time between an egg parasitoid, Trichogramma euproctidis, and an aphid parasitoid, Aphidius ervi. The latter attacks hosts that are able to actively defend themselves, and may thus indirectly influence patch time allocation of the parasitoid. Patch residence time decreased with an increase in temperature in both species. The increased activity levels with warming, as evidenced by the increase in walking speed, partially explained these variations, but other mechanisms were involved. In T. euproctidis, the ability to externally discriminate parasitised hosts decreased at low temperature, resulting in a longer patch residence time. Changes in sex allocation with temperature did not explain changes in patch time allocation in this species. For A. ervi, we observed that aphids frequently escaped at intermediate temperature and defended themselves aggressively at high temperature, but displayed few defence mechanisms at low temperature. These defensive behaviours resulted in a decreased patch residence time for the parasitoid and partly explained the fact that A. ervi remained for a shorter time at the intermediate and high temperatures than at the lowest temperature. Our results suggest that global warming may affect host-parasitoid interactions through complex mechanisms including both direct and indirect effects on parasitoid patch time allocation.

  9. Identification, activity and function determination of several salivary enzymes secreted by Macrosiphum avenae%麦长管蚜唾液中几种酶的鉴定、活力测定与功能分析

    Institute of Scientific and Technical Information of China (English)

    郭光喜; 刘勇; 杨景娟; 马向真

    2006-01-01

    用Parafilm膜夹营养液法,以两种食料介质饲喂麦长管蚜Macrosiphum avenae 3龄若蚜并收集其唾液,对唾液中的酶类进行了鉴定、活力测定和功能分析.结果表明,在20%蔗糖介质提取液中,鉴定有果胶酶、多酚氧化酶和纤维素酶;在水介质提取液中鉴定有纤维素酶;两种介质提取液中都未鉴定出过氧化物酶.酶活力测定结果表明,在20%蔗糖介质提取液中,每30头蚜虫分泌的果胶酶、多酚氧化酶和纤维素酶的酶活力分别为2.59×10-3U/g、7×10-3U/g和7.89×10-3U/g;在水介质提取液中,纤维素酶活力为3.68×10-3U/g.行为反应试验结果表明,果胶酶处理麦苗的挥发物组分能引起麦长管蚜寄生性天敌燕麦蚜茧蜂Aphidius avenae和捕食性天敌七星瓢虫Coccinellaseptempunctata的嗅觉偏好反应,因此,果胶酶在麦长管蚜取食诱导小麦植株的间接防御反应中具有重要作用.

  10. Selectivity lists of pesticides to beneficial arthropods for IPM programs in carrot--first results.

    Science.gov (United States)

    Hautier, L; Jansen, J-P; Mabon, N; Schiffers, B

    2005-01-01

    In order to improve IPM programs in carrot, 7 fungicides, 12 herbicides and 9 insecticides commonly used in Belgium were tested for their toxicity towards five beneficial arthropods representative of most important natural enemies encountered in carrot: parasitic wasps - Aphidius rhopalosiphi (De Stefani-Perez) (Hym., Aphidiidae), ladybirds - Adalia bipunctata (L.) (Col., Coccinellidae), hoverfly - Episyrphus balteatus (Dipt.. Syrphidae), rove beetle - Aleochara bilineata (Col., Staphylinidae) and carabid beetle - Bembidion lampros (Col., Carabidae). Initialy, all plant protection products were tested on inert substrate glass plates or sand according to the insect. Products with a corrected mortality (CM) or a parasitism reduction (PR) lower than 30% were kept for the constitution of positive list (green list). The other compounds were further tested on plant for A. rhopalosiphi, A. bipunctata, E. balteatus and soil for B. lampros and A. bilineata. With these extended laboratory tests results, products were listed in toxicity class: green category [CM or PR carrot. Results showed that all fungicides tested were harmless to beneficials except Tebuconazole, which was slightly harmful for A. bipunctata. Herbicides were also harmless for soil beneficials, except Chlorpropham. This product was very toxic on sand towards A. bilineata and must be tested on soil. All soil insecticides tested were very toxic for ground beneficials and considered as non-selective. Their use in IPM is subject to questioning in view of negative impacts on beneficials. Among foliar insecticides, Dimethoate and Deltamethrin are not recommended for IPM because their high toxicity for all beneficials. The other foliar insecticides were more selective; any of them were harmless for all species tested.

  11. Study of two conditioning methods of parasitoids used in biological control prior to inundative releases in apple orchards

    Directory of Open Access Journals (Sweden)

    Valérie-Anne Dumont

    2011-12-01

    Full Text Available The rosy apple aphid, Dysaphis plantaginea Pass., is a major pest in apple orchards in Belgium. Two micro-hymenopteran parasitoids Aphidius matricariae Haliday and Ephedrus cerasicola Stary are potentially capable of controlling this pest. However, when released in orchards the adult parasitoids tend to disperse. Based on the results of previous work it is proposed that the reason is that the artificial diet in which they are raised does not contain the odors that enable the parasitoids to identify the habitat where there are suitable aphid hosts. To optimize the control and make it economically effective it is important to reduce dispersal. This might be done by conditioning parasitoids during rearing by exposing them to the odors associated with orchards. The odor used in this study was a hydrodistillate of apple leaves, the main host-plant of the targeted aphid. Two methods of conditioning were used: 1 soaking mummies of the parasitoid in p ure hydrodistillate, 2 including a defined concentration of hydrodistillate in the artificial diet used for rearing the parasitoid. They were exposed to either a dilution of 100×, 200× and 1000× in two consecutive generations. The response of adult parasitoids to odors was determined using a dual choice olfactometer. Of the E. cerasicola conditioned by soaking the mummies 70–75% of individuals were attracted to the odor of plants infested with D. plantaginea compared to the 55–60% in the controls. The A.matricariae that were conditioned by feeding them artificial diets containing different concentrations of apple odor for one or two generations, showed no preference for the odor of apple leaves. Second generation adults of E. cerasicola exposed to a 200 times dilution of pure hydrodistillate showed a more marked response to apple odor.

  12. Trans-generational effects of mild heat stress on the life history traits of an aphid parasitoid.

    Directory of Open Access Journals (Sweden)

    Ibrahim Ismaeil

    Full Text Available Temperature changes are common in nature and insects are particularly exposed and sensitive to such variations which can be potential stresses, ultimately affecting life history traits and overall fitness. Braconids have been widely used to study the effects of temperature on host-parasitoid interactions and the present work focused on the solitary endoparasitoid Aphidius ervi Haliday (Hymenoptera: Braconidae Aphidiidae, an efficient biological control agent commercially used against aphids such as the potato aphid Macrosiphum euphorbiae Thomas (Sternorrhyncha: Aphididae. Contrary to previous studies using heat shocks at extreme temperatures, we evaluated the effects of mild heat stresses by transferring young parasitoid adults from the constant temperature of 20°C to either a warm (25°C or hot (28°C temperature, for either 1 h or 48 h. Such treatments are consistent with situations commonly experienced by parasitoids when moved from their rearing conditions to greenhouses or field conditions. The effects were evaluated both on the heat stressed A. ervi adults (G0 (immediate effects and on their first generation (G1 progeny (trans-generational effects. G0 wasps' mortality was significantly affected by the temperature in interaction with the duration of the stress. Longevity of G0 wasps surviving the heat stress was negatively affected by the temperature and females lived longer than males. Heat stress applied to A. ervi parents also had consequences on their G1 progeny whose developmental time, rates of mummification and percentage of parasitoid completing total development were negatively affected. Surprisingly, the egg load at emergence of the G1 female progeny was increased when their mothers had been submitted to a mild heat stress of 25°C or 28°C. These results clearly demonstrate trans-generational phenotypic plasticity, showing that adaptation to thermal stresses may be achieved via maternal effects. This study also sheds light on

  13. Survival to parasitoids in an insect hosting defensive symbionts: a multivariate approach to polymorphic traits affecting host use by its natural enemy.

    Science.gov (United States)

    Bilodeau, Emilie; Guay, Jean-Frédéric; Turgeon, Julie; Cloutier, Conrad

    2013-01-01

    Insect parasitoids and their insect hosts represent a wide range of parasitic trophic relations that can be used to understand the evolution of biotic diversity on earth. Testing theories of coevolution between hosts and parasites is based on factors directly involved in host susceptibility and parasitoid virulence. We used controlled encounters with potential hosts of the Aphidius ervi wasp to elucidate behavioral and other phenotypic traits of host Acyrthosiphon pisum that most contribute to success or failure of parasitism. The host aphid is at an advanced stage of specialization on different crop plants, and exhibits intra-population polymorphism for traits of parasitoid avoidance and resistance based on clonal variation of color morph and anti-parasitoid bacterial symbionts. Randomly selected aphid clones from alfalfa and clover were matched in 5 minute encounters with wasps of two parasitoid lineages deriving from hosts of each plant biotype in a replicated transplant experimental design. In addition to crop plant affiliation (alfalfa, clover), aphid clones were characterized for color morph (green, pink), Hamiltonella defensa and Regiella insecticola symbionts, and frequently used behaviors in encounters with A. ervi wasps. A total of 12 explanatory variables were examined using redundancy analysis (RDA) to predict host survival or failure to A. ervi parasitism. Aphid color was the best univariate predictor, but was poorly predictive in the RDA model. In contrast, aphid host plant and symbionts were not significant univariate predictors, but significant predictors in the multivariate model. Aphid susceptibility to wasp acceptance as reflected in host attacks and oviposition clearly differed from its suitability to parasitism and progeny development. Parasitoid progeny were three times more likely to survive on clover than alfalfa host aphids, which was compensated by behaviorally adjusting eggs invested per host. Strong variation of the predictive power of

  14. PARASITOIDES (HYMENOPTERA DE MOSCAS-DAS-FRUTAS (DIPTERA: TEPHRITIDAE NO SEMIÁRIDO DO ESTADO DO CEARÁ, BRASIL

    Directory of Open Access Journals (Sweden)

    ELTON LUCIO ARAUJO

    2015-09-01

    Full Text Available RESUMO As moscas-das-frutas (Diptera: Tephritidae, Anastrepha spp. e Ceratitis capitata(Wiedemann, são importantes pragas da fruticultura no Brasil. Para desenvolver um sistema sustentável de manejo integrado para este grupo de pragas, é fundamental conhecer os parasitoides (Hymenoptera que podem regular as populações destes tefritídeos. Portanto, o objetivo deste estudo foi relatar a diversidade, a distribuição geográfica e as relações tritróficas dos himenópteros parasitoides de moscas-das-frutas, na região do Baixo Jaguaribe, no semiárido do Estado do Ceará, Brasil. Foram realizadas coletas de frutos em sete municípios da região, no período de maio de 2010 amaio de 2013. Os frutos foram levados para o laboratório, onde foram contados, pesados, colocados em bandejas plásticas com vermiculita e fechadas com tecido voile. Após sete dias, a vermiculita foi peneirada para a obtenção dos pupários das moscas-das-frutas que, em seguida, foram contados e acondicionados em placas de Petri, onde permaneceram até a emergência dos adultos (moscas e/ou parasitoides. Quatro espécies de parasitoides foram encontradas: Doryctobracon areolatus(Szépligeti, Opius bellus Gahan, Utetes anastrephae(Viereck (Braconidae e Tetrastichus giffardianusSilvestri (Eulophidae,sendo o mais frequente e com maior distribuição geográfica na região, D. areolatus. Doryctobracon areolatusfoi mais comum em associação com espécies de Anastrepha - A. sororcula Zucchi, A. obliqua (Mcquart e A. zenildae Zucchi, em frutos nativos e com C. capitata em frutos exóticos. Tetrastichus giffardianus foi obtido apenas em associação com C. capitata, em frutos nativos e exóticos. Estas informações podem servir de base para inserção de parasitoides em futuros programas de manejo integrado de moscas-das-frutas, nas condições do Semiárido brasileiro.

  15. Effect of plant alcohol extracts on vegetable aphids and their parasitoids%植物乙醇提取物对蔬菜蚜虫和蚜茧蜂的影响

    Institute of Scientific and Technical Information of China (English)

    周琼; 梁广文

    2003-01-01

    用药膜法测定8种常见植物的乙醇提取物对桃蚜(Myzus persicae)、瓜蚜(Aphis gossypii)和萝卜蚜(Lipaphis erysimi)的忌避和控制作用,以及对蚜虫重要天敌--菜蚜茧蜂(Aphidius gifuensis)和菜少脉蚜茧蜂(Diaeretiella rapae)存活的影响.结果表明,供试的8种植物乙醇提取物对3种蚜虫都有一定的忌避作用,其中效果最好的是白花非洲山毛豆(Tephrosia vogelli)和樟树(Cinnamomum camphora),对桃蚜、瓜蚜和萝卜蚜的忌避率分别达0.414、0.729、0.547和0.549、0.690、0.729;除黄素馨(Jasminum mesnyi)和草胡椒(Peperomia pellucida)外,其余6种植物乙醇提取物对桃蚜、瓜蚜、萝卜蚜都有较好的控制作用,其中山毛豆、樟树对蚜虫的控制效果最佳,鸡矢藤(Paederia scandena)和芒箕(Dicranopteris dichotoma)仅次于前2种植物,白兰花(Michelia alba)对瓜蚜和萝卜蚜也有较好的控制作用;鱼藤精稀释1000倍对萝卜蚜效果很好,对桃蚜控制作用较差.8种提取物中,山毛豆对蚜茧蜂有较强的毒性,4 h死亡率达63.33%,仅次于鱼藤酮精稀释1000倍(4 h的死亡率达80%),而樟树、羊蹄甲(Bauhinia variegata)、黄素馨、白兰花和草胡椒的乙醇提取物与对照没有差异,对蚜茧蜂安全、无毒.

  16. Altruistic defence behaviours in aphids

    Directory of Open Access Journals (Sweden)

    Brodeur Jacques

    2010-01-01

    Full Text Available Abstract Background Altruistic anti-predatory behaviours pose an evolutionary problem because they are costly to the actor and beneficial to the recipients. Altruistic behaviours can evolve through indirect fitness benefits when directed toward kin. The altruistic nature of anti-predatory behaviours is often difficult to establish because the actor can obtain direct fitness benefits, or the behaviour could result from selfish coercion by others, especially in eusocial animals. Non-eusocial parthenogenetically reproducing aphids form colonies of clone-mates, which are ideal to test the altruistic nature of anti-predatory defence behaviours. Many aphids release cornicle secretions when attacked by natural enemies such as parasitoids. These secretions contain an alarm pheromone that alerts neighbours (clone-mates of danger, thereby providing indirect fitness benefits to the actor. However, contact with cornicle secretions also hampers an attacker and could provide direct fitness to the actor. Results We tested the hypothesis that cornicle secretions are altruistic by assessing direct and indirect fitness consequences of smearing cornicle secretions onto an attacker, and by manipulating the number of clone-mates that could benefit from the behaviour. We observed parasitoids, Aphidius rhopalosiphi, foraging singly in patches of the cereal aphid Sitobion avenae of varied patch size (2, 6, and 12 aphids. Aphids that smeared parasitoids did not benefit from a reduced probability of parasitism, or increase the parasitoids' handling time. Smeared parasitoids, however, spent proportionately more time grooming and less time foraging, which resulted in a decreased host-encounter and oviposition rate within the host patch. In addition, individual smearing rate increased with the number of clone-mates in the colony. Conclusions Cornicle secretions of aphids were altruistic against parasitoids, as they provided no direct fitness benefits to secretion

  17. 0.3%辛硫磷颗粒剂(药肥混剂)防治甘蔗蔗螟田间药效试验%Field Efficacy Trials of 0.3%Phoxim Granules (Insecticide-Fertilizer Mixture) Against Sugarcane Borers

    Institute of Scientific and Technical Information of China (English)

    罗应怡; 周建群; 梁演秋; 闫凤娇; 杨世翡; 黄登熙; 王克林; 蒙艳秋

    2015-01-01

    [目的]为0.3%辛硫磷颗粒剂申报甘蔗农药登记和推广应用提供科学依据。[方法]分别在4个省份开展了为期2年的0.3%辛硫磷颗粒剂防治甘蔗蔗螟的试验,探索适宜的有效剂量,观察和评估该药剂对甘蔗及有益天敌生物的安全性。[结果]推荐0.3%辛硫磷颗粒剂的有效使用剂量为1500~2250 kg/hm2(有效成分用量为4500~6750 g/hm2),该药剂对甘蔗安全、无药害,且有助长作用;对有益的天敌生物(如寄生蜂、蚜茧蜂、赤眼蜂、瓢虫等)没有不良影响,同时对蔗龟、蓟马、象甲等甘蔗害虫具有兼治作用。[结论]本试验研究为0.3%辛硫磷颗粒剂申报甘蔗农药登记和推广应用提供了扎实的试验基础和有力的科学依据。%Aims] To provide a scientific basis for the registration and application of 0.3%phoxim granules in sugarcane. [Methods] The tests were undertaken in 2 years on sugarcane borer in 4 provinces to explore the effective dosage of 0.3%phoxim granules, and to observe and evaluate the its safety on sugarcane and beneficial natural enemies of pests. [Results] Effective dosage of 0.3% phoxim granules was 1500~2250 kg/hm2 (a. i. 4500~6750 g/hm2). It’s safe for sugarcane without injury growth-stimilating. No adverse effects was found on beneficial natural enemies such as parasitic wasps, aphidius insects, trichogramma species and ladybug etc. It can also somewhat control sugarcane beetles, thrips, weevils etc. [Conclusions] This experimental research provides a solid experimental material and strong scientific basis for the registration and application of 0.3%phoxim granules in sugarcane.