Tesi: "Parasitoids"

1

Flanagan, Kate Elizabeth. "Reproductive strategies in parasitoids". Thesis, Imperial College London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.244765.

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2

Byrne, David N., e David E. Bellamy. "Predicting Dispersal by Whitefly Parasitoids". College of Agriculture, University of Arizona (Tucson, AZ), 2000. http://hdl.handle.net/10150/220016.

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These experiments were designed to examine short-range dispersal by the small whitefly parasitoid Eretmocerus eremicus that takes place within the confines of a specifically defined habitat. We were specifically concerned with the impacts of sex and mating status on their dispersal. We hoped to construct predictive models concerning dispersal. In a vertical flight chamber we found that female flight duration was significantly longer (11 times) than that of males and that unmated parasitoids flew approximately three times longer than mated individuals. In field studies 87% of the 4,153 parasitoids captured were males. This occurred in spite of sex ratios being near 1:1 upon release. The difference in dispersal characteristics between males and females may be resource based. It is felt that certain requirements were met within our field plots for males that were not met for females. It is important for males to find mates and they may have done so inside release containers or in close proximity to release sites. While females have a similar requirement, they must also find whitefly hosts to parasitize. It can be assumed that each sex took active steps to accomplish different goals. Males were searching the immediate area of the release sites where mates were plentiful, while females were leaving the 33 ft. radius plots in search of whitefly hosts. We were able to verify models for male dispersal (75% of males were predicted to disperse within 13.5 ft.). Our models predicted that 50% of females would be found within 82 ft. This information will useful when describing movement by E. eremicus and other small insects. It should prove useful when defining release techniques for parasitoids being used as biological control agents.

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3

Inclán, Luna Diego Javier. "Landscape dynamics of tachinid parasitoids". Doctoral thesis, Università degli studi di Padova, 2015. http://hdl.handle.net/11577/3424645.

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Habitat fragmentation and the intensification of agricultural landscapes are among the main drivers affecting parasitoid diversity. Although many empirical and theoretical studies have elucidated the effects of these processes on populations and communities of parasitoids, the majority of the research has been focused on specialized groups of hymenopterans. In this study the highly-diverse group of tachinid parasitoids (Diptera: Tachinidae) was considered as an alternative model system to test the effects of landscape fragmentation and agricultural intensification on the third trophic level. The effects of habitat fragmentation are evaluated in Chapter II. This chapter evaluates the relative importance of habitat loss, decrease of connectivity and their potential interaction on tachinid diversity. This chapter shows that the reduction of habitat area and the loss of connectivity significantly interacted, suggesting that management practices aimed to mitigate the negative effect of habitat fragmentation need to consider the connectivity in the surrounding landscape. In the following chapters, diverse components of the intensification of agricultural landscapes were evaluated. In Chapter III, the diversity of tachinids was examined in relation to farm management (organic vs. conventional) at different spatial scales. This study shows that organic management improved the diversity of tachinids at both the local and landscape scales but only in arable crops while the effect in grasslands was neutral. Thus, any attempt to enhance parasitoid diversity needs to consider the local farming system in relation to the agricultural management in the surrounding landscape. In Chapters IV and V the spatial dynamics and movement of parasitoids between crop and non-crop habitats were evaluated. These chapters show that the spillover of tachinid parasitoids was favored by the low contrast in habitat structure between the crop and non-crop habitats. The highest spillover of parasitoids to arable land was found from herbaceous semi-natural habitats, while woody structure reduced the exchange of individuals between arable crop and non-crop habitats. Finally, in Chapters V and VI the effects of different field margins to enhance farmland biodiversity were examined. The results from these chapters demonstrate that the positive effect of field margins to enhance the diversity of tachinids was related to the type and complexity of these semi-natural habitats. This research provides new insights into the consequences of landscape changes on the diversity of a key functional group that has been long overlooked in ecological and conservation studies. The results will provide guidelines to implement conservation measures to halt or reduce biodiversity loss of this important group of parasitoids.
La frammentazione degli habitat e l’intensificazione dell’agricoltura sono riconosciuti tra i principali fattori che incidono negativamente sulla diversità dei parassitoidi. Nonostante numerosi studi hanno confermato questa tendenza, la gran parte di essi si è concentrata sugli imenotteri parassitoidi. Questa tesi si concentra invece sui tachinidi (Diptera: Tachinidae), considerati come sistema modello alternativo per testare gli effetti della frammentazione del paesaggio e dell’agricoltura intensiva sul terzo livello trofico. In particolare, gli effetti della frammentazione degli habitat sono descritti nel Capitolo II, dove viene valutata l’importanza relativa della perdita dell’habitat, la diminuzione della connettività e la loro potenziale interazione nell’influenzare la diversità dei tachinidi. I risultati dimostrano che la riduzione dell’area e la perdita di connettività dell’habitat interagiscono significativamente, evidenziando che le pratiche di gestione finalizzate a mitigare gli effetti negativi della frammentazione dell’habitat non possono prescindere dal prendere in considerazione la connettività con il paesaggio circostante. Nei capitoli successivi sono stati invece valutati vari impatti connessi all’intensificazione dell’agricoltura. Nel Capitolo III è stato esaminato come la gestione delle aziende agricole (biologica vs. convenzionale) possa influenzare la diversità dei tachinidi a diverse scale spaziali. I risultati dimostrano che la gestione biologica ha un effetto positivo sulla diversità di tachinidi sia a scala locale sia a livello di paesaggio, ma solamente nel caso dei seminativi mentre le praterie non ricevono nessun beneficio dall’agricoltura biologica. Quindi qualsiasi tipo di intervento per migliorare la diversità dei parassitoidi deve considerare il sistema di gestione agricolo locale in relazione al paesaggio circostante. Nei Capitoli IV e V sono state trattate le dinamiche spaziali di spostamento dei parassitoidi tra ambienti coltivati e ambienti naturali. Questi capitoli dimostrano che il movimento dei tachinidi è stato favorito dalla bassa differenziazione strutturale dei due ambienti. Lo scambio di individui più elevato si è avuto dal margine erbaceo mentre il margine caratterizzato dalla presenza delle siepi riduce lo scambio di individui tra i due ambienti. Infine, nei Capitoli V and VI è stato valutato l’effetto di diverse tipologie di margine dei terreni agricoli sulla biodiversità. I risultati ottenuti da questi capitoli dimostrano che gli effetti positivi della presenza di margini semi-naturali sulla diversità dei tachinidi siano correlati alla tipologia e alla complessità degli habitat. Questa tesi fornisce nuove informazioni su come i cambiamenti a livello di paesaggio influenzano la diversità di un gruppo funzionale chiave che è stato per lungo tempo poco considerato negli studi di ecologia e conservazione. I risultati potranno essere utilizzati per definire e implementare innovative misure di conservazione e mitigazione degli impatti considerati.

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Barros, Lucas Silva [UNESP]. "Seletividade de inseticidas ao parasitoide de ovos Trichogramma pretiosum (hymenoptera: trichogrammatidae)". Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/134292.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O uso de inseticidas tem o intuito de prevenir ou reduzir perdas agrícolas aos insetos-praga. Entretanto, quando de maneira irracional provoca consequências negativas aos agroecossistemas, como a eliminação de inimigos naturais. Alternativamente a esta situação, buscando-se a sustentabilidade, prima-se pelo emprego de inseticidas seletivos, os quais possibilitam a integração aos agentes do controle biológico. Destaca-se neste contexto Trichogramma pretiosum, parasitoides de ovos de inúmeras espécies de lepidópteros-praga agrícolas e florestais. Diante do exposto o presente trabalho avaliou a seletividade de novos inseticidas químicos e biológicos (g i.a. L-1 ) às fases de pupa e adulto de T. pretiosum. No bioensaio 1, testou-se clorantraniliprole (0,04; 0,06; 0,08; 0,12; 0,2); flubendiamida (0,1344; 0,288; 0,4416); diflubenzuron (0,384; 0,48); bifentrina/carbosulfano (0,07/0,21; 0,1/0,3; 0,2/0,6; 0,3/0,9); bifentrina (0,216; 0,324). No bioensaio 2, foram testados espinosade (0,096; 0,24; 0,384), indoxicarbe (0,12; 0,24; 0,36); clorfenapir (0,768; 0,96; 1,152; 1,344; 1,536); Baculovírus (HzSNPV) (0,0064; 0,00896; 0,01536; 0,0192). Clorpirifós (1,92) e água destilada foram as testemunhas. Para esses experimentos, ovos de Anagasta kuehniella contendo o parasitoide nas fases de pupa foram expostos aos inseticidas, assim como adultos do parasitoide em contato com uma película seca dos inseticidas quando pulverizados sobre placas de vidro. Avaliou-se o parasitismo e viabilidade até 72 horas após a emergência do parasitoide. As reduções na capacidade benéfica dos parasitoides expostos aos tratamentos foram classificadas em quatro classes: 1, inócuo (<30%); 2, levemente nocivo (30-79%); 3, moderadamente nocivo (80-99%) e 4, nocivo (>99%). Os bioensaios foram realizados sob condições climáticas controladas (25±2ºC, UR de 70±10% e fotofase de 14 horas). Os parâmetros biológicos variaram conforme a fase de desenvolvimento de T. pretiousm, mecanismos de ação, concentração e periodos avaliados. No bioensaio 1 flubendiamida, na menor concentração, foi inócuo (classe 1) à fase de pupa de T. pretiosum no primeiro dia após a emergência. Baculovirus (HzSNPV), no bioensaio 2, em todas as concentrações testadas, foi inócuo (classe 1) à fase pupa e adulto de T. pretiosum no primeiro dia após a emergência. Tais inseticidas mostraram-se seletivos e adequados ao uso no Manejo Integrado de Pragas (MIP). Os demais inseticidas, classe 2, 3 e 4, deverão passar para as próximas etapas dos testes de seletividade.
The use of pesticides has the purpose to prevent or reduce crop losses to insect pests. However, when irrationally causes negative consequences to agricultural ecosystems, as the elimination of natural enemies. Alternatively to this, aiming for sustainability, it suggests the use of selective insecticides, which enable integration with biological control agents. In this context Trichogramma pretiosum, eggs parasitoids to numerous species of agricultural and forestry lepidopteran pests. Given the above the present study evaluated the selectivity of new chemical and biological insecticides (g a.i. L-1 ) to the pupal stage and adult of T. pretiosum. In the bioassay 1, was tested clorantraniliprole (0.04; 0.06; 0.08; 0.12; 0.2); flubendiamide (0.1344; 0.288; 0.4416); diflubenzuron (0.384; 0.48); bifenthrin/carbosulfan (0.07/0.21; 0.1/0.3; 0.2/0.6; 0.3/0.9); bifenthrin (0.216; 0.324). In the bioassay 2, were tested spinosad (0.096; 0.24; 0.384), indoxicarbe (0.12; 0.24; 0.36); chlorfenapyr (0.768; 0.96; 1.152; 1.344; 1.536); Baculovirus (HzSNPV) (0.0064; 0.00896; 0.01536; 0.0192). Chlorpyrifos (1.92) and distilled water were the control. For these experiments, Anagasta kuehniella eggs containing the parasitoid in pupal stage were exposed to insecticides, as well as adult parasitoids in contact with a dry film of insecticides when sprayed on glass plates. Was evaluated the parasitism and viability until 72 hours after the emergence of the parasitoid. The reductions in the beneficial capacity of parasitoids exposed to the treatments were classified into four classes: 1, harmless (<30%); 2, slightly harmful (30-79%); 3, moderately harmful (80-99%) and 4, harmful (> 99%). Bioassays were conducted under controlled climatic conditions (25 ± 2° C, RH of 70 ± 10% and photoperiod of 14 hours). The biological parameters varied according to the development of T. pretiousm, mechanisms of action, concentration and evaluated periods. In the bioassay 1 flubendiamide, in the lowest concentration, was harmless (class 1) to the pupal stage of T. pretiosum on the first day after emergence. Baculovirus (HzSNPV) in the bioassay 2, in all concentrations tested, was harmless (class 1) to the pupal stage and adult parasitoids on the first day after emergence. Such insecticides were selective and suitable for use in Integrated Pest Management (IPM). Other insecticides, class 2, 3 and 4, should move to the next steps of selectivity tests.

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5

Hougardy, Evelyne. "Resource sharing in bark beetle parasitoids". Doctoral thesis, Universite Libre de Bruxelles, 2003. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/211330.

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6

Beck, Markus Hans. "Molecular genetics of host manipulation and competition in an insect parasitoid system". Title page, contents and abstract only, 1998. http://web4.library.adelaide.edu.au/theses/09ACP/09acpb393.pdf.

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Bibliography: leaves 108-128. Maternal protein secretions from the parthenogenetic endoparasitoid wasp Venturia canescens Gravenhorst (Hymenoptera: Ichneumonidae) were analysed regarding their ability to protect the parasitoid egg against the host immune system. These secretions include nucleic acid-free glycoproteins, called virus-like particles (VLPs) that are produced in the ovarian calyx gland. Results found that VLP-free calyx fluid has the ability to actively suppress host defence reactions, rather than VLPs on the egg surface being solely responsible for the protection of the egg. It was shown the VLP-free calyx fluid contains serine protease-inhibitor activity capable of transiently inhibiting melanogenisis and hemocyte spreading in the host. This indicates that immediately after oviposition the egg surface is not fully protected against host defence reactions. However, at later stages the egg seems to have acquired an immunologically inert surface, and is therefore protected after the suppressive activity of the calyx fluid has disappeared.

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7

Morais, Adriana Barnabé 1984. "Estudos populacionais de Revena rubiginosa, Boheman 1936 (Coleoptera: Curculionidae) e de seus parasitoides (Hymenoptera: Braconidae e Ichneumonidae)". [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/317471.

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Orientador: João Vasconcellos Neto
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
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Mestrado
Parasitologia
Mestra em Parasitologia

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8

Lynch, Liam David. "Factors in population regulation by insect parasitoids". Thesis, University of Liverpool, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366238.

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9

Pritchard, J. "Host specificity in aphid parasitoids (Hymenoptera : Aphidiidae)". Thesis, Bucks New University, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.384680.

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10

Byrne, David N., e David E. Bellamy. "Refinement of Release Techniques for Whitefly Parasitoids". College of Agriculture, University of Arizona (Tucson, AZ), 1999. http://hdl.handle.net/10150/219970.

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Although they are currently effectively controlled by chemicals, sweet potato whiteflies have the potential to once again be a dominant pest in Arizona vegetables. We need to explore alternatives such as biological control so that we are not reliant solely on pesticides. We have been examining dispersal by the whitefly parasitoid Eretmocerus sp. in order to find more effective ways to deploy these agents in the field. We have learned in the laboratory that these wasps are efficient flyers since they are capable of moving into strong winds for more than 30 min. We also now know that most flight takes place within a short distance of the release point. We also have a better understanding of differences between male and female flight. This, along with other information we have obtained, will lead to our ability to effectively release these and parasitoids of other insect pests as well.

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11

Abreu, Cássia Isabela Vilela de. "Aspectos bionômicos de geometridae (Lepidoptera) associados a plantas de mata atlântica na reserva biológica da Serra do Japi, Jundiaí, SP". Universidade Federal de São Carlos, 2014. https://repositorio.ufscar.br/handle/ufscar/2120.

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Universidade Federal de Sao Carlos
Immature stages of Geometridae (Lepidoptera) and their parasitoids (Ichneumonoidea and Chalcidoidea) were recorded and collected in two areas of Serra do Japi Municipal Biological Reserve, in Jundiaí, São Paulo. Occurrence of larvae were recorded associated with 14 plant species, collected in two environments: semideciduous mesophytic forest (MS) and understory between eucalipto (SB). The sampling period was from September 2011 to September 2012 and the larvae were kept in laboratory until emergence of adult parasitoids or Geometridae. On MS were collected 143 larvae, from this total, 12 were parasitized and 131 reached the adult stage; on SB, 129 larvae were collected, 12 were parasitized and 117 reached the adult stage. The most abundant species in the MS was Eois tegularia (Geometridae, Larentiinae), with 64 larvae. Physocleora sp.1, was the specie with the highest association of parasitoids, with 6 parasitized larvae. In SB, the most abundant species were the Nephodia aff. panacea (Geometridae, Ennominae), with 32 larvae collected, and also the species with the highest number of association with parasitoids. Piper sp. (Piperaceae), showed the highest number of larvae collected in the MS and Alchornea triplinervia (Euphorbiacea) of SB. The highest number of larvae parasitized on MS were recorded and collected for Croton floribundus (Euphorbiaceae), 6 larvae; on SB, the largest number of parasitized larvae was Alchornea triplinervia. Among the parasitoids, the genus Diolcogaster (Hymenoptera, Braconidae, Microgastrinae) were the most abundant with 18 samples. It was registered a new kind of Aleiodes (Hymenoptera, Braconidae, Rogadinae), associated with Physocleora grossica. larvae and Ischnopteris sp. on MS associated Alchornea triplinervia (Euphorbiacea). From complementary collections for parasitoids, with Malaise trap, Moericke trap and vegetation sweep, the Glyptapanteles genus follow by Diolcogaster, both Hymenoptera, Braconidae, Microgastrinae that emerged from geometridae larvae were the most abundant. For parasitoids, the results indicated the importance of obtaining from host larvae in the laboratory, besides the use of the main methods of collecting adults.
Estágios imaturos de Geometridae (Lepidoptera) e seus parasitoides (Ichneumonoidea e Chalcidoidea) foram estudados na Reserva Biologica Municipal da Serra do Japi, Jundiaí, São Paulo. Foi registrada a ocorrência de larvas associadas a 14 espécies de plantas, amostradas em dois ambientes: mata mesófila semidecídua (MS) e sub-bosque nativo em meio a eucalipto (SB). O período de amostragem foi de setembro de 2011 a setembro de 2012 e as larvas foram mantidas em laboratório até emergência de adultos de Geometridae ou de seus parasitoides. Na MS foram obtidas 143 larvas, das quais, 12 estavam parasitadas e 131 atingiram o estágio adulto; no SB, 129 larvas foram obtidas, 12 estavam parasitadas e 117 atingiram o estágio adulto. A espécie mais abundante na MS foi Eois tegularia (Geometridae, Larentiinae), com 64 larvas. Physocleora sp.1 foi a espécie com maior associação com parasitoides, com 6 larvas parasitadas. No SB, a espécie mais abundante foi Nephodia aff. panacea (Geometridae, Ennominae), com 32 larvas obtidas e também a espécie com o maior número de associações com parasitoides. Piper sp. (Piperaceae), apresentou o maior número de larvas amostradas na MS e Alchornea triplinervia (Euphorbiaceae) no SB. O maior número de larvas parasitadas na MS foi registrado para Croton floribundus (Euphorbiaceae); no SB, o maior número de larvas parasitadas e coletadas ocorreu em Alchornea triplinervia. Entre os parasitoides, o gênero Diolcogaster (Hymenoptera, Braconidae, Microgastrinae) foi o mais abundante, com 18 exemplares. Foi registrada uma nova espécie de Aleiodes (Hymenoptera, Braconidae, Rogadinae), associada a larvas de Physocleora grossica e Ischnopteris sp. na MS associadas à Alchornea triplinervia (Euphorbiaceae). Das coletas complementares de parasitoides com armadilhas Malaise, de Moericke e varredura da vegetação, o gênero Glyptapanteles, seguido por Diolcogaster, ambos Hymenoptera, Braconidae, Microgastrinae foram os mais abundantes. Para os parasitoides, os resultados indicaram a importância da sua obtenção a partir de larvas hospedeiras, além da utilização de outros métodos de coleta de adultos.

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Harvey, Jeffrey Alan. "The nutritional ecology of a host-parasitoid interaction". Thesis, University of Liverpool, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241470.

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13

Kalule, Twaha. "Tritrophic interactions between crucifers, aphids and hymenopteran parasitoids". Thesis, Imperial College London, 2000. http://hdl.handle.net/10044/1/8794.

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14

Barrette, Maryse. "Patch exploitation strategies of parasitoids in variable environments". Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=96976.

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In nature, resources are not uniformly distributed and most often occur aggregated in patches. The profitability of a patch largely depends on the density of resources, the inner composition (types of prey) and the distance from other patches in the habitat. Variability can thus arise between patches but resources may also vary within a patch. In this thesis I have investigated how foragers, such as parasitoids, estimate their resource profitability and explored the impact of variability between resources at different levels: choice of the resource and allocation of time in a patch. When Aphidius colemani parasitize different instars of Myzus persicae, fourth instar aphids provided the best fitness gain to parasitoids, whereas second instar aphids were the most profitable in terms of fitness gain rate. Parasitoid females preferred second instar hosts, suggesting that their decision maximizes fitness gain rate over fitness gain. Fitness gain rate is a reliable predictor of animal's choice for foragers exploiting resources that impose additional time cost due to their mobility. Parasitoid females stayed 59% longer in rich patches than in poor patches. However, intra-patch variance did not influence patch residence time. Foragers depleted to the same level a set of patches of similar quality but having different intra-patch compositions. Foragers update their estimate of patch value using a Bayesian incremental-decremental rule in which the estimated patch value varies with the quality of the resource encountered. Patch residence times increase with travel time between patches. Parasitoid females specialized initially on the more profitable hosts and, as the patch depleted, they switched to a generalist diet by accepting more frequently the less profitable hosts. The point at which they switched from specialist to generalist occurred later when travel times and hence patch residence times were short. By affecting the patch exploitation strategy, travel time also determines the composition of hosts left behind, the "giving up composition". The change in the relative density of remaining host types alters aphid populations' age structure.This thesis shows that A. colemani females are able to cope with variability in their resources by optimizing their host choice and their patch time allocation.
Dans la nature, les ressources ne sont pas distribuées uniformément mais se retrouvent plutôt sous forme de parcelles. La profitabilité d'une parcelle dépend de la densité des ressources qu'elle contient, de sa composition et de la distance entres les parcelles. La variabilité existe donc entre les parcelles mais également à l'intérieur d'une parcelle. Cette thèse explore la façon dont les parasitoïdes estiment la profitabilité de leurs ressources et explore également l'impact de la variabilité entre les ressources à différents niveaux : le choix de la ressource et l'allocation du temps dans la parcelle.Lorsqu'Aphidius colemani parasite différents stades de Myzus persicae, les pucerons de quatrième et deuxième stade procurent repectivement le meilleur gain d'aptitude et le meilleur taux de gain d'aptitude. Les femelles parasitoïdes préfèrent les hôtes maximisant leur taux de gain d'aptitude. Le taux de gain d'aptitude est un prédicteur fiable du choix lorsque les animaux exploitent des ressources imposant un coût temporel dû à leur mobilité.Les femelles parasitoïdes sont demeurées 59% plus longtemps dans les parcelles riches que dans les parcelles pauvres. Toutefois, la variance à l'intérieur de la parcelle n'a pas influencé le temps de résidence. Les femelles ont exploité au même niveau des parcelles de qualité similaire mais de compositions différentes. Les femelles actualisent leur estimation de la qualité de la parcelle qu'elles exploitent grâce à une règle Bayesienne incrémentale-décrémentale. Le temps de résidence dans les parcelles augmente avec la durée de déplacement. Les femelles se spécialisent initialement sur les hôtes les plus profitables, puis, à mesure que la parcelle s'épuise, elles deviennent généralistes en acceptant les hôtes moins profitables. Le moment où elles passent de la stratégie spécialiste à généraliste survient plus tard lorsque les durées de déplacement sont courtes. En affectant la stratégie d'exploitation, la durée de déplacement détermine également la composition des hôtes restants. Le changement de densité relative des hôtes restants altère la structure d'âge des populations de pucerons.Cette thèse montre que les femelles A. colemani sont capables de faire face à la variabilité dans leurs ressources en optimisant leur choix d'hôtes et leur allocation du temps dans les parcelles.

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Gisloti, Laura Jane 1983. "Aspectos ecologicos e biologicos de Neosilba perezi (Romero & Ruppel, 1973) (Diptera: Lonchaeidae) associados a cultura de mandioca Manihot esculenta Crantz". [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/317952.

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Orientador: Angelo Pires do Prado
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: Este trabalho estabelece alguns aspectos biológicos e ecológicos de Neosilba perezi (Romero & Ruppel, 1973) (Diptera: Lonchaeidae), que ainda constam como desconhecidos na literatura mundial. Dentre as pragas da mandioca, a mosca-dos-brotos, N. perezi,é uma das mais observadas, atacando brotos jovens e ocasionando brotamentos laterais na região atacada. Os trabalhos referentes a essa espécie de lonqueídeo são escassos e os dados a respeito da perda de produção o ocasionada pelo ataque da mosca não são bem estabelecidos. Os objetivos deste trabalho foram caracterizar a infestação por N. perezi no sudoeste do estado de São Paulo correlacionando cada área de estudo, separadamente para cada parâmetro particular de temperatura, precipitação pluviométrica e idade das plantas; avaliar o parasitismo de larvas de N. perezi em dez genótipos de mandioca; conhecer alguns aspectos da interação de parasitoidismo associada larvas de N. perezi; além de caracterizar o desenvolvimento vital do inseto em condições controladas de laboratório e por fim e mostrar os estágios de ovo, larva e adulto. Foram realizadas análises quinzenais em cada área de estudo, no período de março de 2008 a fevereiro de 2009 para obtenção dos índices de parasitismo pelas larvas de N. perezi em brotos de mandioca e os índices de parasitoidismo por braconídeos parasitóides das larvas da mosca. Na análise dos genótipos em relação à infestação por N. perezi, estes foram plantados na área experimental do Departamento de Biologia Vegetal da Universidade de Campinas e assim o índice de infestação foi calculado para cada genótipo, no período de junho de 2008 a janeiro de 2009. O estudo do ciclo de vida da mosca foi realizado através da coleta de ovos em campo, os quais foram mantidos em uma dieta elaborada neste trabalho a qual possibilitou o desenvolvimento total, de ovo a adulto de N. perezi. A dinâmica populacional da mosca-dos-brotos na região estudada está correlacionada, separadamente, com a temperatura, com a pluviosidade e com a idade da plantas, de forma que temperatura acima de 23°C, ou pluviosidade relativamente alta ou ainda idades tardias das plantas afetaram negativamente a população deste inseto. O genótipo "IAC Caapora 105-66" e o genótipo "IAC Cascuda" mostram-se menos suscetíveis à infestação por este inseto enquanto o genótipo "IAC 15" apresentou as maiores porcentagens de infestação. Quanto ao parasitoidismo por braconídeos em larvas de N. perezi, foi constatado que a porcentagem de ataque foi de 24,3% sugerindo que esta interação possa ser um importante fator na dinâmica populacional de N. perezi. Assim, estabelecemos uma descrição sucinta dos aspectos biológicos e ecológicos de N. perezi, que facilitarão estudos subseqüentes relacionados a esta família, além de elucidar alguns aspectos do parasitismo destas larvas em brotos de mandioca que poderão ser usados no esclarecimento de possíveis riscos a cultura desta planta
Abstract: This research establishes some new biological and ecological aspects of Neosilba perezi (Romero & Ruppel, 1973) (Diptera: Lonchaeidae. Among the pests of cassava, the shoot fly, N. perezi, is one of the most studied, attacking young shoots and causing side shoots in the attacked region. The researches related to this of fly are few and the data about production loss caused by the attack of the fly are not well known. The objectives of this research were to characterize infestation by N. perezi in the southwest of the State of São Paulo, Brazil by correlating separately each area, for each particular parameter of temperature, rainfall and the age of plants; evaluate larvae parasitism of N. perezi in ten manioc genotypes; know some aspects of the interaction of parasitoidism associated to N. perezi larvae ; in addition to characterize the vital development of the insect under laboratory controlled conditions and finally describe the stages of egg, larva and adult on the insect. Analyses were carried out fortnightly in each area of study from March 2008 to February 2009 in order to obtain the levels of parasitism by larvae of N. perezi in cassava shoots and parasitoidism levels by Braconidae parasitoids of the fly larvae. In analyzing the genotypes in relation to the infestation by N. perezi, these were planted in the experimental area of Plant Biology Department at the State University of Campinas and so the level of infestation was calculated for each genotype, from June 2008 to January 2009. Finally the life cycle study of the fly was carried out by collecting eggs in the field, which have been kept on a diet drawn up in this research in which made it possible for the total development, from the egg to the adult one of N. perezi. The results indicate that the fly population dynamics in the buds in the studied region is correlated, separately, with temperature, rainfall and the age of plants, so that temperature above 23ºC, or elatively high quantity of rains or even late plant ages seem negatively affect the population of this insect. Furthermore, the infestation by the fly behaved differently in the face of the different genotypes in a way that the genotype IAC Caapora 105-66 and genotype IAC Cascuda are less susceptible to infestation by this insect while the genotype IAC 15 presented the highest percentages of infestation. Regarding to parasitoidism by braconideous in N. perezi larvae was found that parasitoidism percentage was fairly high suggesting that this interaction can be an important factor in N. perezi populational dynamics. Thus, we have established a short description of biological and ecological aspects of N. perezi, which will make subsequent studies easier related to this family, as well as elucidate certain parasitism aspects of these larvae in cassava shoots which may be used in possible risks explanation to the crop of this plant
Mestrado
Mestre em Parasitologia

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16

Maia, Danielle de Paula 1981. "Interação tritrófica entre Pachymerus cardo (Fahraeus), Pachymerus nucleorum (Fabricius) (Coleoptera, Chrysomelidae, Bruchinae) e seus parasitoides em populações de Syagrus romanzoffiana (Cham.) Glassman (Arecaceae)". [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/317470.

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Orientador: João Vasconcellos Neto
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: A dinâmica populacional de plantas é fortemente influenciada pela dispersão das sementes. A predação desses propágulos ocasiona significativa redução de sementes viáveis, podendo diminuir a população dessa planta. Besouros da subfamília Bruchinae (Chrysomelidae), antigamente conhecidos como bruquídeos, são um grupo de insetos predadores de sementes que atacam principalmente frutos de palmeiras (Família Arecaceae), podendo por sua vez, suas larvas serem atacadas por vespas parasitoides. Neste trabalho aprofundaram-se os estudos das interações tri-tróficas entre a palmeira Syagrus romanzzofiana, besouros da subfamília Bruchinae (Pachymerinae), como herbívoros predadores de suas sementes, e uma espécie de parasitoide Heterospilus prosopodis (Hymenoptera: Braconidae), como terceiro nível trófico. A área de estudo foi a Universidade Estadual de Campinas, Campinas, São Paulo. Durante vinte e quatro meses foram acompanhadas quarenta palmeiras mensalmente, sendo registradas observações pontuais sobre a fenologia. No mesmo período, frutos maduros recém-caídos do cacho eram coletados para posteriormente serem acondicionados em gaiolas, que eram dispostas ao nível do solo, para mensurar o ataque dos besouros e seus parasitoides. A produção de flores, frutos verdes e frutos maduros ocorreram ao longo de todo o período de estudo. Foram encontradas duas espécies de besouros predando as sementes de S. romanzoffiana: Pachymerus cardo e Pachymerus nucleorum. Esta última ocorreu ao longo de todo o período de estudo, sendo que o pico de predação ocorreu no mês de dezembro. A predação por P.cardo não ocorreu de forma constante durante os anos de estudo. Registrou-se o ataque às larvas de Pachymerus sp. por vespas parasitoides pertencentes à espécie Heterospilus prosopodis. O parasitismo não foi constante durante o tempo do estudo, observando maior emergência de parasitoides nos meses mais quentes e chuvosos. Forças top-down talvez sejam mais importantes na regulação desta interação tritrófica Syagrus romazzofiana, Pachymerus spp. e seu parasitoide onde os efeitos são manifestados principalmente no ciclo seguinte da interação
Abstract: The population dynamics of plants is strongly influenced by seed dispersal. Predation these seedlings causes significant reduction of viable seeds, which can decrease the population of this plant. Subfamily Bruchinae beetles (Chrysomelidae), formerly known as bruchids, are a group of insect seed predators that attacks mainly palm fruits (Family Arecaceae), and can turn their larvae are attacked by parasitoid wasps. In this work deepened studies of tritrophic interactions between the palm S.romanzzofiana, beetles sufamilia Bruchinae (Pachymerinae) as predators of herbivores and their seeds a kind of parasitoid Heterospilus sp. (Hymenoptera: Braconidae) as the third trophic level. The study area was the University of Campinas in Campinas - SP. For twenty-four months were monitored monthly and forty palm off on phenological observations recorded in the same period, newly fallen ripe fruit bunch were collected for later packed into cages that were placed at ground level, to measure the attack of the beetles and their parasitoids. . Production of flowers, green fruits and ripe fruits occur throughout the study period. We found two species of beetles preying on seeds of S. romanzoffiana: Pachymerus cardo and Pachymerus nucleorum, the latter occurred throughout the study period, with peak predation occurred in december and predation by P.cardo not occurred steadily during the years of study. Recorded the attack on larvae Pachymerus sp. by wasp parasitoids of the species Heterospilus prosopodis. Parasitism was not constant during the time of the study, watching largest emergence of parasitoids in the warmer months and rainy
Mestrado
Parasitologia
Mestra em Parasitologia

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17

Perera, Halamba Arachchige Sumanasiri. "Effect of host plant on mealybugs and their parasitoids". Thesis, Imperial College London, 1990. http://hdl.handle.net/10044/1/8646.

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18

Aegerter, James Nicholas. "A three trophic level interaction : pines, pests and parasitoids". Thesis, University of York, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.321676.

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19

Cournoyer, Michel 1976. "Host selection behavior of the adult parasitoid Microctonus hyperodae Loan (Hymenoptera:Braconidae:Euphorinae) and the egg parasitoid Anaphes victus Huber (Hymenoptera:Mymaridae), parasitoids of the carrot weevil, Listronotus oregonensis LeConte (Coleoptera:Curculionidae)". Thesis, McGill University, 2003. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=80244.

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The carrot weevil, Listronotus oregonensis LeConte (Coleoptera: Curculionidae), is an important pest of carrot in northeastern North America. The objective of this study was to determine the host selection stimuli used by two L. oregonensis parasitoids: the adult parasitoid Microctonus hyperodae Loan and the egg parasitoid Anaphes victus Huber.
In the first chapter, the response of M. hyperodae females to various odor components from potential hosts and host plants was tested with a Y-olfactometer.
In the second chapter, the effect of L. oregonensis adult sex, feces and movement on host selection behavior of M. hyperodae females was evaluated by quantifying L. oregonensis adult movement and various M. hyperodae female behaviors in an arena.
In the third chapter, the response of A. victus females to different L. oregonensis related odor components was evaluated using a filter paper of which half was moistened with odor components and the other half with water.

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20

Robert, Godshen Robert Pallipparambil. "Mass rearing of Bracon cephi (Gahan) and B. lissogaster Muesebeck parasitoids of wheat stem sawfly, Cephus cinctus Norton, and temperature-induced mortality in host immatures". Thesis, Montana State University, 2006. http://etd.lib.montana.edu/etd/2006/robert/RobertG0806.pdf.

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21

Calbert, Gregory. "Information, game theory and patch defence in the parasitic wasp Trissolcus basalis Wollaston (Hymenoptera : Scelionidae) /". Title page, contents and summary only, 1999. http://web4.library.adelaide.edu.au/theses/09PH/09phc143.pdf.

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22

Field, Scott A. "Patch exploitation and defence in the egg parasitoid Trissolcus basalis Wollaston (Hymenoptera : Scelionidae)". Title page, contents and summary only, 1997. http://web4.library.adelaide.edu.au/theses/09PH/09phf456.pdf.

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Bibliography: leaves 175-191. Trissolcus basalis (Wollaston) is a solitary endoparasitoid of the eggs of many pentatomid bugs. It is a quasi-gregarious scelenoid and aggressively defends host patches. In the Adelaide (S. Aust.) region its most abundant host is the native horehound bug, Agonoscelis rutila (Fabricius). This study of patch defence draws together important areas of research in parasitoid behavioural ecology, including the theories of adaptive superparasitism, sex ratio decisions, foraging behaviour and contest resolution.

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Li, Dongmei. "Immune reactions involved in parasitoid-host interactions /". Title page, contents and abstract only, 2002. http://web4.library.adelaide.edu.au/theses/09PH/09phl6926.pdf.

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24

Perry, Stuart John. "Community dynamics of leaf-miners annd their parasitoids on Alder". Thesis, Imperial College London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.321761.

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25

Budenberg, William James. "Role of honeydew in locating cereal aphids by their parasitoids". Thesis, Imperial College London, 1990. http://hdl.handle.net/10044/1/47791.

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26

Simonato, Mauro. "Genetics and genomics of pine processionary moths and their parasitoids". Doctoral thesis, Università degli studi di Padova, 2010. http://hdl.handle.net/11577/3426558.

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The pine processionary moth (Thaumetopoea spp.), an important defoliator of Pinus spp. in the Mediterranean area, is recently expanding its range in response to climate change and anthropogenic factors. Therefore it's important to outline the way in which this pest can colonize new areas, and to do this molecular markers seem to be the most suitable tools. In the introduction I present some of the molecular markers used in the last years to study ecological and evolutionary problems related to insects. The main aim of my work was to analyze the genetic variability of pine processionary moth in its present range and so to try to reconstruct the recent and past colonization history of this pest. Secondly, another goal was to characterize the genetic structure of pine processionary moth parasitoids to better understand the factors involved in their differentiation such as in tracking their host on different pine species. In the first study I extended a work already begun on the population genetic of pine processionary moth to the populations of the Near East. The main issue of this study was to understand the origin of population attacking the Israel pine plantations and in second place to genetically characterize all the populations in the range. Moreover, this study shows the utility of the use of both nuclear and mitochondrial markers for the different information they can yield. In this case they permitted to track a gender-related dispersal, which could be important to maintain genetic variability in expansion areas. In the second study, I contributed to outline the genetic structure of pine processionary moth in the whole range. Through the mitochondrial markers used in the previous studies it was possible to define the main events occurred to this species in the past, identifying glacial refugia and the main splitting events among the different lineages. In northern Africa, a new unexpected genetic clade was found analyzing populations that were previously considered, on a morphological base, to belong to a subspecies of the two already described pine processionary moth species. In the third study, I contributed to the sequencing of the entire mitochondrial genome of Ochrogaster lunifer, an Australian species belonging to the same subfamily of the pine processionary moth. This study, besides to represent the first step to have insights into the taxonomy of the family, gave useful information about the best markers to be used in population genetic studies on Lepidoptera. In the fourth study, I dealt with the population genetic of two egg parasitoid species of the pine processionary moth: the specialist Baryscapus servadeii and the generalist Ooencyrtus pityocampae. The main goal of this study was to test the presence of a host plant association in these two parasitoids and to compare the genetic patterns of a specialist and a generalist. In the specialist parasitoid populations analyzed it seems to be present a genotype mostly associated with the host plant. Moreover, unlike the generalist, the specialist doesn’t show to have a genetic pattern spatially structured. This could be related to a higher mobility of the specialist, and hence to its strategy in finding hosts. These findings provide useful information to predict the behavior of parasitoids in expanding areas. On the whole, the four contributions provide suggestions for the range wide management of the pest, and insights into the evolutionary history of the group, including projections on the potential for adaptation to ongoing climate change.
La processionaria del pino (Thaumetopoea spp.), un importante defogliatore dei pini in tutta l’area del Mediterraneo, ha mostrato, nel corso degli ultimi decenni, un’espansione del suo areale in risposta sia al cambiamento climatico che a fattori antropici. E' quindi importante delineare le modalità con cui questa specie riesce a colonizzare nuove aree e per far questo i marcatori molecolari sembrano essere gli strumenti più utili. Nell’introduzione sono presentate alcuni dei marcatori molecolari usati negli ultimi anni per studiare problemi ecologici ed evolutivi in relazione agli insetti. L'obiettivo principale del mio lavoro è consistito nell’analizzare la variabilità genetica della processionaria del pino nel suo attuale areale e nel tentare di ricostruire la storia della sua colonizzazione recente e passata. In secondo luogo, un ulteriore obiettivo è stato quello di caratterizzare la struttura genetica di alcuni parassitoidi della processionaria del pino per comprendere meglio quali sono i fattori coinvolti nel loro differenziamento quale può essere la ricerca dell’ospite su diverse specie di pino. Nel primo lavoro ho esteso a popolazioni del Vicino Oriente uno studio già iniziato sulla genetica di popolazione della processionaria del pino. Lo scopo principale di questo lavoro era quello di capire l’origine delle popolazioni che attaccano le piantagioni di pino in Israele e in secondo luogo di caratterizzare geneticamente tutte le popolazioni presenti nella regione. Questo studio ha inoltre mostrato l'utilità dell'impiego di marcatori mitocondriali e nucleari per il diverso tipo di informazione che possono produrre. In questo caso è stato possibile individuare una dispersione in relazione al sesso degli individui, processo che potrebbe essere importante per il mantenimento della variabilità genetica nelle aree di espansione. Nel secondo lavoro, è stata delineata la struttura genetica della processionaria del pino in tutto il suo areale. Attraverso i marcatori mitocondriali utilizzati nello studio precedente è stato possibile definire per questa specie i principali eventi occorsi nel passato, identificando così i rifugi glaciali e i principali eventi di separazione tra le diverse popolazioni. Nel Nord Africa, è stato individuato in questo modo un nuovo clade geneticamente ben definito, analizzando popolazioni precedentemente considerate, su base morfologica, appartenenti ad una sottospecie di una della due specie di processionaria già descritte. Nel terzo lavoro, è stato descritto l’intero menoma mitocondriale di ochrogaster lunifer, una specie Australina appartenete alla stessa sottofamiglia della processionaria del pino. Questo studio, oltre a rappresentare il primo passo per un chiarimento della tassonomia di questa famiglia di Lepidotteri, ha prodotto informazioni utili riguardo ai marcatori che possono essere utilizzati negli studi di genetica di popolazione dei Lepidotteri. Nel quarto lavoro, ho preso in considerazione la genetica di popolazione di due parassitoidi oofagi della processionaria del pino: lo specialista Baryscapus servadeii e il generalista Ooencyrtus pityocampae. L’obiettivo principale di questo studio era di testare la presenza di un’associazione con la pianta ospite in questi due parassitoidi e di comparare inoltre la struttura genetica di uno specialista con quella di un generalista. Nelle popolazioni del parassitoide specialista analizzate sembra essere presente un genotipo per lo più associato con una delle piante ospiti della processionaria. Inoltre, a differenza del generalista, il parassitoide specialista non presenta una variabilità genetica strutturata spazialmente. Questo potrebbe essere messo in relazione alla più alta mobilità dello specialista e quindi alla sua strategia per individuare l’ospite. Tali nuove informazioni su questi parassitoidi possono rivelarsi utili nel predire il loro comportamento nelle aree di espansione. Nel complesso, i quattro contributi presentati qui forniscono suggerimenti per il controllo di questo insetto infestante su larga scala e una maggiore conoscenza della storia evolutiva del gruppo, includendo inoltre delle previsioni sul potenziale di adattamento di queste specie in relazione ai cambiamenti climatici in corso.

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Kloss, Thiago Gechel. "Bacillus thuringiensis e Trichogramma spp. no manejo de populações de Helicoverpa zea (BODDIE, 1850)". Universidade Federal do Espírito Santo, 2011. http://repositorio.ufes.br/handle/10/6544.

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Among the biological control agents, Bacillus thuringiensis Berliner (1911) stands out the most and the egg parasitoid of Trichogramma Westwood (1833). Diverse factors can interfere with the effectiveness of these agents and investigations are necessary to succeed in the utilization of these agents isolated or together. In this case, the objective of this study was to select the populations of Trichogramma and the isolated or formulated of B. thuringiensis the most adequate for the management of populations of Helicoverpa zea (BODDIE, 1850) and to evaluate the influence of variation in the populations of H. zea in these agents. Moreover, the effects of interaction between them in host populations were also evaluated. In the evaluation of the Trichogramma agents, ten females population, individually received a piece of cardboard containing eggs with a determined population of H. zea. The characteristics analyzed were parasitism (%), emergence of individuals (%), sex ratio and number of adults per host egg. In the analysis of B. thuringiensis, 34 isolates and the formulated commercial Agree® and Dipel® were used and also inoculated on a diet, in a concentration 3 x 108 spores mL-1. Furthermore, lethal concentration of the isolates and more virulent formulates were estimated. In the assessment of the interaction between these agents, the cardboard with the eggs of population of H. zea were sprayed with different isolates and formulated B. thuringiensis and were offered the females of population of Trichogramma. The characteristics evaluated where the same previously described for the populations of Trichogramma, except the female longevity. The biological control agents Trichogramma and B. thuringiensis showed adequate for the management of the populations of H. zea. In addition, the use of the agents together generated few negative effects and in some cases even strengthened the parasites of Trichogramma sp., showing the use of them together which can increase the efficiency of the control of populations of H. zea. Alterations caused by the difference population of the biological characteristics of Trichogramma and in the levels of virulence of the isolates and formulated of B. thuringiensis were registered, but these variations weren t sufficient to generate undesirable levels of these characteristics in the management of the insect populations
Entre os agentes de controle biológico destacam-se a bactéria Bacillus thuringiensis Berliner (1911) e o parasitoide de ovos Trichogramma Westwood (1833). Diversos fatores podem interferir na eficiência desses agentes e investigações são necessárias para se obter sucesso na utilização deles de forma isolada ou em conjunto. Sendo assim, o objetivo deste estudo foi selecionar as populações de Trichogramma e os isolados ou formulados de B. thuringiensis mais adequados para o manejo de populações de Helicoverpa zea (BODDIE, 1850) e avaliar a influência da variação populacional de H. zea nesses agentes. Além disso, foram avaliados os efeitos da interação entre eles nas populações hospedeiras. Na avaliação do agente Trichogramma, fêmeas de dez populações receberam individualmente cartelas contendo ovos de uma determinada população de H. zea. As características analisadas foram parasitismo (%), emergência dos indivíduos (%), razão sexual e número de adultos por ovo do hospedeiro. Na análise de B. thuringiensis, foram utilizados 34 isolados e os formulados comerciais Dipel® e Agree®, que foram inoculados sobre a dieta, na concentração 3 x 108 esporos mL-1. Além disso, foi realizada a estimativa da concentração letal (CL50) para os isolados e formulados mais virulentos. Na avaliação da interação entre os agentes, cartelas com ovos das populações de H. zea foram pulverizados com diferentes isolados e formulados de B. thuringiensis e oferecidas para fêmeas de uma população de Trichogramma. As características avaliadas foram as mesmas descritas acima para as populações de Trichogramma, com exceção da longevidade das fêmeas. Os agentes de controle biológico Trichogramma e B. thuringiensis se mostraram adequados para o manejo de populações de H. zea. Além disso, o uso conjunto desses agentes gerou poucos efeitos negativos e em alguns casos até potencializou o parasitismo de Trichogramma sp., evidenciando que o uso deles em conjunto pode aumentar a eficiência de controle das populações de H. zea. Alterações ocasionadas pela diferença populacional nas características biológicas de Trichogramma e nos níveis de virulência dos isolados e formulados de B. thuringiensis foram registradas, porém essas variações não foram suficientes para gerar níveis indesejáveis dessas características no manejo das populações de insetos

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Lomeli-Flores, Refugio. "Natural enemies and mortality factors of the coffee leafminer Leucoptera coffeella (Guerin-Meneville) (Lepidoptera: Lyonetiidae) in Chiapas, Mexico". Texas A&M University, 2007. http://hdl.handle.net/1969.1/85837.

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Through field surveys and laboratory experiments, this study assessed in part the impacts of host plant, natural enemies, and weather variables on coffee leafminer Leucoptera coffeella distribution and abundance at two elevations and two rainfall levels in coffee farms in Chiapas, Mexico. In addition, a checklist of Neotropical coffee leafminer parasitoids was assembled from field collections and literature review. Coffee leafminer field incidence was positively correlated with leaf nitrogen content and age, but in laboratory experiments coffee leafminers grew larger, developed faster, and had higher survivorship on leaves with moderate (2.9±0.01%) versus low (2.5±0.04%) or high (3.4±0.01%) nitrogen level, and on tough versus soft leaves. Ovipositional preference was not generally for leaves that maximized offspring performance. Coffee leafminer incidence was higher during the rainy versus dry season, and at low versus high elevation. Shade cover reduced ambient temperatures within coffee farms, but did not significantly affect coffee leafminer incidence. The coffee leafminer predator complex included 16 morphospecies, ~88% of them ants (Formicidae), and contributed >58% of real mortality. Predation rates were higher at high versus low elevation, and under high versus low rainfall. Predation was the main source of coffee leafminer mortality throughout the year, and was highest during the rainy season, when coffee leafminer incidence was highest. Neotropical coffee leafminer parasitoids included 23 species of Eulophidae and seven of Braconidae. In Chiapas, 22 larval parasitoid morphospecies were collected. Egg and pupal parasitoids were not recovered. Parasitism accounted for <10% of real mortality, and rates were 8-10-fold higher at low versus high elevation. Parasitism rates were not significantly influenced by temperature or rainfall. Coffee leafminer oviposited mostly during the night, and less under low versus high temperatures. Average monthly temperature minima, which occur during the night, were generally lower at high (~18°C) versus low (~20°C) elevation farms. The incidence and abundance of coffee leafminer may differ between elevations due to differences in temperature, because at high elevation lower temperatures likely reduced coffee leafminer oviposition, and may have increased its mortality rate as a consequence of longer development time and exposure to natural enemies.

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29

Coleman, Ross Antony. "Herbivore behaviour, multitrophic interactions and a lack of wound-induced defence in a member of the Cruciferae". Thesis, University of Southampton, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242558.

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30

Longley, Martin. "The effects of pyrethroid insecticides upon parasitic hymenoptera in the cereal ecosystem". Thesis, University of Southampton, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.295728.

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31

Sarfati, Michal. "Diapause by seed predators and parasitoids in Chionochloa mast seeding communities". Thesis, University of Canterbury. Biological sciences, 2008. http://hdl.handle.net/10092/2194.

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Chionochloa, a genus of snow tussock grasses native to New Zealand, exhibits pronounced mast seeding. Chionochloa suffers very high levels of pre-dispersal flower and seed predation by three main insects: Eucalyptodiplosis chionochloae, a cecidomyiid midge, which is formally described here; Megacraspedus calamogonus, a gelechiid moth and Diplotoxa similis, a chloropid fly. Seven species of parasitoids that attack these seed predators were discovered. Four species parasitize M. calamogonus (one tachinid fly and three hymenopteran wasps), one parasitizes D. similis (Hymenoptera: Eulophidae) and two parasitize E. chionochloae, (a pteromalid wasp Gastrancistrus sp. and a platygastrid wasp Zelostemma chionochloae, which is given a formal description here). The abundance, predation levels by each of the insect species, and interactions between all the organisms in the community were studied across three elevations at Mount Hutt over three summer seasons. M. calamogonus was most abundant at 450 m altitude during all three seasons. D. similis was most common at 1070 m altitude, while its predation levels peaked in low flowering seasons and decreased in high seasons. E. chionochloae was abundant in all three altitudes and increased its predation levels with increasing flowering intensity. E. chionochloae was confirmed to use prolonged diapause of at least three years. Prolonged diapause was also confirmed in its two parasitoids. Chionochloa plants were manipulated with various treatments to test the effect on diapause in E. chionochloae and its two parasitoids. Treatments included plant warming, root pruning, gibberellic acid sprayed on the plants and combinations of these treatments. All three insects changed their emergence in response to some treatments and therefore it was suggested that combined with risk-spreading diapause, they may use some predicting to emerge from prolonged diapause. E. chionochloae control their diapause following some of the cues that Chionochloa use for flowering, while Z. chionochloae and Gastrancistrus in some cases follow their host’s cues and in others use similar cues as Chionochloa plants. Emergence or diapause predictions differed across elevations and plant species in all three insect seed/flower predators. E. chionochloae had female-biased sex ratios in different populations even after prolonged diapause. There was week evidence that both parasitoid species are female-biased in the first emergence year and male-biased after more than one year in diapause. Therefore it was suggested that diapause is not more costly for females of E. chionochloae and its parasitoid than for males. Females of all three species were not found to be better predictors (i.e, more likely to respond to treatments by not entering extended diapause) than males. The complex interactions of all the organisms in this web are thought to be sensitive to climate, and it was suggested that the global climate change may alter this sensitive system.

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32

Permalloo, Shradanand. "Biological and taxonomic studies on parasitoids associated with some Tephritidae (Diptera)". Thesis, Cardiff University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.277104.

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33

Kati, Amalia. "The influence of aphid parasitoids on the development of their hosts". Thesis, Imperial College London, 2009. http://hdl.handle.net/10044/1/5284.

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Changes in wing development and development through the stadia of Aphis fabae are examined after parasitisation by Aphidius colemani along with the underlying mechanisms. Parasitoid oviposition into nymphs of winged gynoparae of A. fabae shows that wing development is inhibited and the earlier parasitism takes place, the stronger the effect. Consideration of the timing of events indicates that the active component(s) is most likely injected during oviposition and is not related to hatching and growing of the parasitoid larva. When extracts of venom glands are injected into late-second stadium aphids, many develop to fourth-stadium possessing rudimentary wingbuds, show developmental arrest and often die while moulting to the adult stage. Injections with extracts of female or male parasitoids into later stadia give similar results with regard to development to the adult but aphids injected in the late-fourth stadium develop normally. Experiments with long-day winged virginoparae reveal similar results in development to the adult but injections into long-day wingless aphids, which develop more rapidly, show this effect only when performed early in the third stadium. The earlier the injection before the final moult the greater the effect of the extract on preventing adult development. The results indicate that there is an active factor(s) in the female parasitoid’s venom that disrupts wing development and/or inhibits development to the adult; the loss of activity after treatment at 100 °C or with protease makes it likely that the factor(s) is a protein. Surprisingly, injections of extracts from male parasitoids have similar effects. The location and function of such a factor(s) in males are unknown. Fast Protein Liquid Chromatography is used to fractionate the parasitoid extracts and bioassays reveal activity in fractions 16-25. Aphidius ervi venom also inhibits development of A. fabae (a non-host) whereas A. colemani venom has no effect on the development of Megoura viciae (a non-host). Injection with lipopolysaccharides and infection with a fungal pathogen are used to test whether stimulation of the immune response affects wing development in the host and the possibility that the host is in control of inhibiting its own wing development in order to support its immune system is discussed.

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34

Nofemela, Sicelo Robert. "Studies on parasitoids of the diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), in South Africa". Thesis, Rhodes University, 2004. http://eprints.ru.ac.za/86/.

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35

Grbin, Lynne C. "Sublethal effects of Bacillus thuringiensis Berliner on the diamondback moth, Plutella xylostella (L.), and its natural enemy, Cotesia plutellae Kurdjumov : implications for resistance management". Title page, table of contents and summary only, 1997. http://web4.library.adelaide.edu.au/theses/09PH/09phg785.pdf.

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Bibliography: leaves 165-188. This research examines biological and behavioural interactions among the diamond-back moth, Plutella xylostella L. (Lepidoptera: Plutellidae), Cotesia plutellae Kurdjumov (Hymenoptera: Braconidae) and the microbial insecticide, Bacillus thuringiensis Berliner. A deterministic simulation model is developed describing the influence of C. plutellae on the evolution of resistance to Bt in a diamond-back moth poulation.

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36

Souza, Carolina da Silva e. "Hymenoptera parasitoides associados à Geometridae (Lepidoptera) em quatro áreas da Fazenda Canchim (Embrapa Pecuária Sudeste, São Carlos, SP) com ênfase nos Microgastrinae (Braconidae) e Campopleginae (Ichneumonidae)". Universidade Federal de São Carlos, 2012. https://repositorio.ufscar.br/handle/ufscar/2053.

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Larvae of Geometridae (Lepidoptera) were collected with entomological umbrella during 13 months in Agrosilvopastoral System and Reforestation at Canchim Farm (Embrapa Pecuária Sudeste, São Carlos, SP) area, and maintained in laboratory until the emergence of adults or of its parasitoids. Hymenopterous parasitoids of the subfamilies Microgastrinae (Braconidae) and Campopleginae (Ichneumonidae) were obtained from collected larvae, and during 10 months were also captured by Malaise traps in a fragment of Semideciduous Forest, Reforestation, Agrosilvopastoral System and Sorghum crop, in the same area of Farm. In the Agrosilvopastoral System the Geometridae larvae were collected in four plant species and in the Reforestation area, in 12 species. The greatest abundance and species richness of hosts were obtained in the Agrosilvopastoral System; the Reforestation had the greatest number of genera of Geometridae. In the Reforestation the most abundant genus of Geometridae was Macaria (Ennominae); in this site, the host plant with the highest number of larvae collected were Aegiphila sellowiana. In the Agrosilvopastoral System, the most abundant species of Geometridae was Eupithecia sp. (Larentiinae); in this site, Anadenanthera colubrina (Vell.) Brenan (Mimosaceae) was the host that had the highest number of collected larvae and parasitized larvae. In the Reforestation, the rate of parasitism over Geometridae larvae was higher than the recorded in the Agrosilvopastoral System. Most of the species of parasitoids obtained from larvae that occurred in Agrosilvopastoral System and Reforestation, were captured by Malaise traps. The genres that parasitized the largest number of Geometridae larvae were Glyptapanteles (Microgastrinae) and Charops (Campopleginae). The parasitoids obtained with Malaises generally were more abundant in the Reforestation, and the most abundant specie in this area was Cotesia sp. (Braconidae, Microgastrinae), and in the Agrosilvopastoral System was Campoletis sp. (Ichneumonidae, Campopleginae). For Microgastrinae fauna sampled with Malaise, the area with highest species richness index was the Reforestation, and the fragment of Forest showed the highest value for evenness. For Campopleginae fauna, also obtained with Malaise trap, the Agrosilvopastoral System had the highest species richness and greatest evenness. Was observed different patterns in the distribution of the abundance of hymenopterous parasitoids and Geometridae larvae in different environments, given the same climatic conditions.
Larvas de Geometridae (Lepidoptera) foram coletadas com guarda-chuva entomológico durante 13 meses em Sistema Agrossilvipastoril e Reflorestamento em área da Fazenda Canchim (Embrapa Pecuária Sudeste, São Carlos, SP), e mantidas em laboratório até a emergência dos adultos ou de seus parasitoides. Himenópteros parasitoides das subfamílias Microgastrinae (Braconidae) e Campopleginae (Ichneumonidae) foram obtidos das larvas coletadas, e durante 10 meses foram também capturados por armadilhas Malaise em Fragmento de Floresta Estacional Semidecídual, Reflorestamento, Sistema Agrossilvipastoril e Plantio de Sorgo, na mesma área da Fazenda. No Sistema Agrossilvipastoril as larvas de Geometridae foram coletadas em quatro espécies de planta e no Reflorestamento, em 12 espécies. A maior abundância e riqueza de espécies de hospedeiros foram obtidas no Sistema Agrossilvipastoril; o Reflorestamento apresentou um maior número de gêneros de Geometridae. No Reflorestamento o gênero mais abundante de Geometridae foi Macaria (Ennominae); nesse local, a planta hospedeira com maior número de larvas coletadas foi Aegiphila sellowiana. No Sistema Agrossilvipastoril, a espécie de Geometridae mais abundante foi Eupithecia sp. (Larentiinae); nesse local, Anadenanthera colubrina (Vell.) Brenan (Mimosaceae) foi a planta hospedeira que apresentou o maior número de larvas coletadas e larvas parasitadas. No Reflorestamento, a taxa de parasitismo sobre as larvas de Geometridae foi maior do que a registrada no Sistema Agrossilvipastoril. A maior parte das espécies de parasitoides obtidos das larvas que ocorreram no Sistema Agrossilvipastoril e Reflorestamento, foram capturados por armadilhas Malaise. Os gêneros que parasitaram o maior número de larvas de Geometridae foram Glyptapanteles (Microgastrinae) e Charops (Campopleginae). Os parasitoides, obtidos com Malaise, em geral foram mais abundantes no Reflorestamento, e a espécie mais abundante nessa área foi Cotesia sp. (Braconidae, Microgastrinae), e no Sistema Agrossilvipastoril foi Campoletis sp. (Ichneumonidae, Campopleginae). Para a fauna de Microgastrinae amostrada com Malaise, a área com maior índice de riqueza de espécies foi o Reflorestamento, e o fragmento de Mata apresentou o maior valor para equitabilidade. Para a fauna de Campopleginae, também obtida com armadilha Malaise, o Sistema Agrossilvipastoril apresentou a maior riqueza de espécies e a maior equitabilidade. Foram observados diferentes padrões na distribuição da abundância de himenópteros parasitoides e larvas de Geometridae nos diferentes ambientes, diante das mesmas condições climáticas.

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37

Vieira, Jací Mendes. "Biologia em temperaturas alternantes e exigências térmicas de Diaphorina citri Kuwayama, 1908 (Hemiptera: Liviidae) e Tamarixia radiata (Waterston, 1922) (Hymenoptera: Eulophidae) visando ao seu zoneamento em regiões citrícolas do estado". Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/11/11146/tde-01082016-154434/.

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A pesquisa teve por objetivo determinar o desenvolvimento, o número de gerações e a constante térmica de Diaphorina citri Kuwayama, 1908 (Hemiptera: Liviidae) e Tamarixia radiata (Waterston, 1922) (Hymenoptera: Eulophidae), sob 20 combinações de temperaturas alternantes que simulam as condições de Limeira, Tatuí, Araraquara, Santa Cruz do Rio Pardo e Votuporanga, áreas citrícolas do estado de São Paulo, nas quatro estações do ano. Paralelamente, discutem-se as estimativas dos períodos de liberação do parasitoide associados ao alerta fitossanitário desenvolvido pelo FUNDECITRUS. Foi estudado o desenvolvimento de D. citri e T. radiata, sendo registrado o tempo necessário para completarem o ciclo biológico. A partir destes dados, foi calculada a constante térmica e o número de gerações da praga e do parasitoide para cada uma das condições propostas. Com base na duração do desenvolvimento de D. citri, foi definido o momento ideal para liberação de T. radiata em campo. Os resultados da determinação do número de gerações de D. citri e de T. radiata, baseando-se em temperaturas alternantes, foram comparáveis ao modelo desenvolvido em temperaturas constantes, sendo que as variações existentes entre os dois modelos se deveram à inclusão do período de pré-oviposição que foi variável em função da temperatura. A previsão do número de gerações se ajustou mais a T. radiata do que a D. citri, sendo propostos fatores de correção para casos em que a constante térmica observada superou 10- 15% do valor determinado em laboratório. Observou-se que uma geração de D. citri variou de 22,9 a 74,2 dias, no verão e inverno para as simulações de Votuporanga e Tatuí, respectivamente; por outro lado, nas mesmas condições, uma geração de T. radiata pode variar de 9,8 a 21,6 dias. A relação entre o número de gerações de D. citri: T. radiata no decorrer do ano é superior a 1:2, sendo de 1: 2,58; 1: 2,47; 1: 2,28; 1: 2,28; 1: 2,34, respectivamente, para as simulações de Limeira, Tatuí, Araraquara, Santa Cruz do Rio Pardo e Votuporanga. A regressão linear mostrou que o número de gerações de D. citri é melhor explicado pela média das temperaturas diurna e noturna, enquanto que para T. radiata, apenas pela temperatura diurna. Os valores extremos de dias para liberação de T. radiata após o alerta fitossanitário, correspondem às regiões de Avaré e Bebedouro. Os resultados indicam que há uma variação no desenvolvimento da praga e do seu parasitoide entre as regiões e que há necessidade de validação em campo; no entanto, se confirmados, permitirão o uso mais eficiente do parasitoide T. radiata, se tornando um componente auxiliar ao sistema de alerta e ao Manejo Integrado dessa importante doença, o HLB.
This study determined the development, number of generations and thermal constant of the HLB vector Diaphorina citri Kuwayama, 1908 (Hemiptera: Liviidae) and the parasitoid Tamarixia radiata (Waterston, 1922) (Hymenoptera: Eulophidae) under 20 combinations of alternating temperatures that simulated the conditions of five citrus-growing areas of São Paulo state (Limeira, Tatuí, Araraquara, Santa Cruz do Rio Pardo and Votuporanga) in the four seasons. The estimated optimum release time of the parasitoid is discussed in relation to a phytosanitation alert developed by FUNDECITRUS. The development time and time needed to complete the life cycles of D. citri and T. radiata were assessed. The thermal constant and number of generations of the pest and parasitoid for each temperature condition were calculated based on these data. Based on the development time of D. citri, the optimum time to release T. radiata in the field was established. The estimated number of generations of D. citri and T. radiata in alternating temperatures was comparable to the model developed at constant temperatures; the differences between the two models were due to the inclusion of the pre-oviposition period, which varied as a function of temperature. The estimated number of generations was larger for T. radiata than D. citri, and correction factors were proposed for those cases in which the observed thermal constant exceeded 10-15% of the value determined in the laboratory. Generation times of D. citri ranged from 22.9 days in summer to 74.2 days in winter for the simulations for Votuporanga and Tatuí. Under the same conditions, one generation of T. radiata may range from 9.8 to 21.6 days. The ratio between the annual number of generations of D. citri: T. radiata was higher than 1: 2, ranging from 1: 2.58; 1: 2.47; 1: 2.28; 1: 2.28; 1: 2.34 for the simulations for Limeira, Tatuí, Araraquara, Santa Cruz do Rio Pardo and Votuporanga, respectively. Linear regression analysis showed that the number of generations of D. citri is best explained by the mean diurnal and nocturnal temperatures, whereas for T. radiata, only by the mean diurnal temperature. The extreme values for optimum release day of T. radiata after a phytosanitation alert were found for Avare and Bebedouro. The results indicate that the development of the pest and its parasitoid differ among areas, and there is need for validation in the field. However, if confirmed, these data will allow more efficient use of the parasitoid T. radiata as a complementary component of the alert system and of Integrated Management of HLB.

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38

Nofemela, Sicelo Robert. "Studies on parasitoids of the diamondback moth, Plutella xylostella (L.) (Lepidoptera:Plutellidae), in South Africa". Connect to this title online, 2004. http://eprints.ru.ac.za/86/.

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39

Javed, Muhammad Asif. "Insecticide application studies for whitefly control". Thesis, Imperial College London, 2001. http://hdl.handle.net/10044/1/8662.

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40

Viana, Marina Aparecida [UNESP]. "Performance de Trichogramma pretiosum Riley, 1879 e T. exiguum Pinto & Platner, 1978 (Hymenoptera: trichogrammatidae) em ovos de populações de Plutella xylostella (LINNAEUS, 1758) (Lepidoptera: Plutellidae) sob ação de Bacillus thuringiensis Berliner, 1915 (Bacillales: Bacillaceae)". Universidade Estadual Paulista (UNESP), 2012. http://hdl.handle.net/11449/91313.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O objetivo do trabalho foi estudar a performance de Trichogramma exiguum e Trichogramma pretiosum, em ovos de populações de Plutella xylostella sob ação de a Bacillus thuringiensis. O experimento constou de quatro tratamentos por parasitoide, sendo: ovos da população suscetível (Ps) a Bt com mais de 100 gerações em laboratório (Testemunha); ovos da população submetida à pressão de seleção ao isolado HD-1 por mais de 40 gerações (Res); ovos da Ps pulverizados com HD-1 e ovos da Ps pulverizados com o isolado T08.024. As fêmeas foram individualizadas e alimentadas com uma gotícula de mel. Os testes realizados foram avaliados: a resposta funcional, capacidade de parasitismo, tabela de vida e teste de preferência. Para análise de resposta funcional foram testadas as densidades de 2, 4, 8, 16, 32 e 64 ovos, e a melhor densidade utilizada para os demais testes, utilizando as densidades de 32 e 8 para T. pretiosum e T. exiguum respectivamente. Os parâmetros avaliados foram: parasitismo, viabilidade, razão sexual, longevidade e período ovo-adulto. B. thuringiensis afeta os ovos de P. xylostella influenciando o parasitismo de Trichogramma sp., de maneira positiva ou negativa dependendo do isolado utilizado. A interação Trichogramma-Bt pode sofrer alterações de acordo com a espécie do parasitoide utilizada e do isolado de Bt, sendo necessário estudo das interações especificas antes de seu uso em conjunto
This research aimed the study of the performance of Trichogramma exiguum and Trichogramma pretiosum in eggs of Plutella xylostella populations under the action of Bacillus thuringiensis (Bt). The experiments consisted of four treatments for each parasitoid, as follows: eggs of the susceptible population (Ps) to Bt with more than 100 generations in the laboratory (Witness), eggs of the population subjected to selection pressure to isolate HD-1 for more than 40 generations (Res); Ps eggs sprayed with HD-1 and eggs of Ps sprayed with isolate T08.024. The females were individualized and fed with a drop of honey. Some parameters were evaluated: the functional response, parasitism capacity, life table and preference test. For analysis of functional response the densities of 2, 4, 8, 16, 32 and 64 eggs were tested, and the best densities were used for other tests, that were, 32 and 8 eggs for T. pretiosum and T. exiguum respectively. The parameters evaluated were: parasitism, viability, sex ratio, longevity and egg-adult period. Bacillus thuringiensis affected the eggs of Plutella xylostella influencing parasitism of Trichogramma sp., positively or negatively, depending on the isolate used. The interaction Trichogramma-Bacillus thuringiensis may change according to the species of parasitoid and the Bt strain used, it is necessary to study the specific interactions prior to use their two agents together

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41

Viana, Marina Aparecida. "Performance de Trichogramma pretiosum Riley, 1879 e T. exiguum Pinto & Platner, 1978 (Hymenoptera: trichogrammatidae) em ovos de populações de Plutella xylostella (LINNAEUS, 1758) (Lepidoptera: Plutellidae) sob ação de Bacillus thuringiensis Berliner, 1915 (Bacillales: Bacillaceae) /". Jaboticabal : [s.n.], 2012. http://hdl.handle.net/11449/91313.

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Orientador: Sérgio Antonio de Bortoli
Coorientador: Ricardo Antonio Polanczyk
Banca: Arlindo Leal Boiça Júnior
Banca: Fernando Hercos Valicente
Resumo: O objetivo do trabalho foi estudar a performance de Trichogramma exiguum e Trichogramma pretiosum, em ovos de populações de Plutella xylostella sob ação de a Bacillus thuringiensis. O experimento constou de quatro tratamentos por parasitoide, sendo: ovos da população suscetível (Ps) a Bt com mais de 100 gerações em laboratório (Testemunha); ovos da população submetida à pressão de seleção ao isolado HD-1 por mais de 40 gerações (Res); ovos da Ps pulverizados com HD-1 e ovos da Ps pulverizados com o isolado T08.024. As fêmeas foram individualizadas e alimentadas com uma gotícula de mel. Os testes realizados foram avaliados: a resposta funcional, capacidade de parasitismo, tabela de vida e teste de preferência. Para análise de resposta funcional foram testadas as densidades de 2, 4, 8, 16, 32 e 64 ovos, e a melhor densidade utilizada para os demais testes, utilizando as densidades de 32 e 8 para T. pretiosum e T. exiguum respectivamente. Os parâmetros avaliados foram: parasitismo, viabilidade, razão sexual, longevidade e período ovo-adulto. B. thuringiensis afeta os ovos de P. xylostella influenciando o parasitismo de Trichogramma sp., de maneira positiva ou negativa dependendo do isolado utilizado. A interação Trichogramma-Bt pode sofrer alterações de acordo com a espécie do parasitoide utilizada e do isolado de Bt, sendo necessário estudo das interações especificas antes de seu uso em conjunto
Abstract: This research aimed the study of the performance of Trichogramma exiguum and Trichogramma pretiosum in eggs of Plutella xylostella populations under the action of Bacillus thuringiensis (Bt). The experiments consisted of four treatments for each parasitoid, as follows: eggs of the susceptible population (Ps) to Bt with more than 100 generations in the laboratory (Witness), eggs of the population subjected to selection pressure to isolate HD-1 for more than 40 generations (Res); Ps eggs sprayed with HD-1 and eggs of Ps sprayed with isolate T08.024. The females were individualized and fed with a drop of honey. Some parameters were evaluated: the functional response, parasitism capacity, life table and preference test. For analysis of functional response the densities of 2, 4, 8, 16, 32 and 64 eggs were tested, and the best densities were used for other tests, that were, 32 and 8 eggs for T. pretiosum and T. exiguum respectively. The parameters evaluated were: parasitism, viability, sex ratio, longevity and egg-adult period. Bacillus thuringiensis affected the eggs of Plutella xylostella influencing parasitism of Trichogramma sp., positively or negatively, depending on the isolate used. The interaction Trichogramma-Bacillus thuringiensis may change according to the species of parasitoid and the Bt strain used, it is necessary to study the specific interactions prior to use their two agents together
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42

Vårdal, Hege. "From Parasitoids to Gall Inducers and Inquilines : Morphological Evolution in Cynipoid Wasps". Doctoral thesis, Uppsala universitet, Systematisk zoologi, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-3975.

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Abstract (sommario):

One of the large lineages of parasitic wasps, the Cynipoidea, exhibits three distinctly different life modes. Slightly more than half of the about 3000 species are parasitoids in insect larvae, whereas the remaining species are associated with plants, either as gall inducers or as inquilines (guests feeding on plant tissue in galls). The main focus of this thesis has been to identify morphological changes associated with the shifts between life modes. Particular attention was paid to structures believed to be important in gall initiation. Comparative anatomical studies of the egg, larva and venom apparatus were performed, including representatives of parasitoids, gall inducers and inquilines. Examination of gross morphology and ultrastructure revealed that the eggs of the gall inducers are larger and surrounded by a thicker shell than the parasitoid eggs. These differences may be related to the fact that the gall inducer egg contains sufficient egg yolk for the embryo during the entire egg period, whereas the parasitoid egg often absorbs nutrients through the eggshell. Furthermore, the gall inducer egg is probably more exposed to desiccation and therefore a thicker and more resistant eggshell is crucial. Comparing the terminal-instar larvae of about 30 species of parasitoids, gall inducers and inquilines, extensive morphological variation was found, particularly in the head and mouthpart features. The variation was summarized in 33 morphological and one life-history character and parsimony analyses were performed. The resulting phylogenetic estimates were largely in accordance with previous analyses of adult morphology and molecular data. The larval data point to a single origin of the inquilines, in agreement with adult morphology but in conflict with molecular data. The venom apparatus was found to be quite uniform in structure among a sample of 25 species of cynipoid species. It consists of a very short venom duct, a reservoir and a single unbranched venom gland. With few exceptions, the venom apparatus is conspicuously larger relative to the female metasoma in the gall inhabiting species than in the parasitoids. We found little evidence of anatomical structures that could facilitate chemical communication between the gall-inducer embryo and the surrounding plant tissue through the thick eggshell. On the other hand, the enormous venom glands and reservoirs, which are apparently not used for defence, suggest that the adult female plays a significant role in gall induction by injecting secretions into the host plant when laying eggs.

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43

Lardner, Ross Michael. "Comparative host stage utilization of two parasitoids of Liriomyza brassicae (Diptera: Agromyzidae)". Adelaide Thesis (Ph.D.) -- University of Adelaide, 1991. http://hdl.handle.net/2440/21631.

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44

Skeffington-Didychuk, Kimberly Anne. "A study of the parasitoids associated with Creosia curvalana, Kearfoot, Tortricidae, lepidoptera". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0014/MQ30028.pdf.

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45

Zebrowski, Deirdre A. "The parasitoids of spruce budworm, Choristoneura fumiferana Lederer (Lepidoptera: tortricidae), in Manitoba". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ32289.pdf.

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46

Jönsson, Martin. "Responses to oilseed rape and cotton volatiles in insect herbivores and parasitoids /". Alnarp : Dept. of Crop Science, Swedish Univ. of Agricultural Sciences, 2005. http://epsilon.slu.se/200514.pdf.

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47

Baumgart, Eligiusz Adam Iwo. "Parasitoids and beetles of decaying wood : the role of fungi and volatiles". Thesis, Imperial College London, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.520955.

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48

Murchie, Archie Kelso. "Parasitoids of cabbage seed weevil and brassica pod midge in oilseed rape". Thesis, Keele University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318159.

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Abstract (sommario):

Oilseed rape (Brassica napus (L. )), the second most important arable crop in the UK after cereals, is attacked during the summer by cabbage seed weevil Ceutorhynchus assimilis (Paykull) and brassica pod midge Dasineura =brassicae (Winnertz). In mainland Europe, these two 'pests are known to be attacked by a range of hymenopteran parasitoids but virtually nothing is known about their parasitoids in the UK. This study found that the ectoparasitic Trichomalus perfectus (Walker) (Pteromalidae) was the most abundant species attacking C. assimilis, achieving, in unsprayed crops, levels of parasitism up to 73%. The egg-larval Platygaster subuliformis Kieffer (Platygastridae) was reared from D. brassicae for the first time and is probably a new species record for the UK; it was the most abundant species attacking the midge in winter rape. The endoparasitic Omphale clypealis (Thomson) (Eulophidae) was the most abundant species attacking D. brassicae in spring rape. The complexity of assessing parasitism in the multivoltine D. brassicae is discussed. In-field temporal and spatial distributions of hosts and parasitoids were studied using a novel randomization test and the results related to known biological characteristics of species. Using a new design of insect flight trap, P. subuliformis was shown to respond to 2-phenylethyl isothiocyanate and O. clypealis to 2-propenyl isothiocyanate, both volatile secondary plant compounds, produced by brassicaceous plants on damage. Field trials demonstrated that the post-flowering application of the organophosphate insecticide triazophos, has a detrimental effect on T. perfectus, killing adults and larvae, whereas the synthetic pyrethroid alphacypermethrin was less harmful because it was applied before the main migration of T. perfectus into the crop. The importance of the parasitoids ' of rape pests to integrated protection strategies for the crop are discussed.

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49

Glinwood, Robert Thomas. "Responses of aphid parasitoids to aphid sex pheromones : laboratory and field studies". Thesis, University of Nottingham, 1998. http://eprints.nottingham.ac.uk/13861/.

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The behavioural responses of aphid parasitoids (Hymenoptera: Braconidae: Aphidiinae) to aphid sex pheromones were investigated in the laboratory and field. In a wind tunnel bioassay, Aphidius eadyi, Aphidius rhopalosiphi, Diaeretiella rapae, Ephedrus plagiator, Praon myzophagum and Praon volucre responded to the aphid sex pheromone components nepetalactone and nepetalactol. P. myzophagum reared on two different host aphid species showed different responses to combinations of nepetalactone and nepetalactol in the wind tunnel, indicating that long term laboratory rearing may influence parasitoid responses to aphid sex pheromones. The ability of two aphid parasitoids to learn aphid sex pheromones through prior exposure in the presence of host aphids was investigated. The generalist E. plagiator showed evidence of associative learning, whereas the specialist Aphidius ervi did not. When A. ervi was exposed to the pheromone without contact with host aphids, the parasitoid response was reduced by habituation. Exposure to aphid sex pheromone during laboratory host attack trials had no effect on the host attack behaviour of A. ervi. In laboratory cage experiments, aphid sex pheromone lures increased the retention of A. rhopalosiphi, but not by Praon volucre, on aphid-infested plants. In a wind tunnel bioassay, aphid sex pheromone enhanced the attraction of A. ervi to a plant-host complex. In the field, aphid sex pheromone lures increased parasitisation rates by A. rhopalosiphi and P. volucre on aphid-infested potted plants. A series of potted plant experiments indicated that the pheromone may increase parasitisation of aphids by A. rhopalosiphi, but not P. volucre, at a distance of 1m away from the lure. The effect of baiting plots of winter wheat with aphid sex pheromone was investigated in two field experiments. In 1996, the number of parasitoid mummies was higher in baited plots than in unbaited plots, and the synchrony between aphid and parasitoid populations was closer in baited plots. In 1997, aphid sex pheromone had no effect on parasitisation levels. The results are discussed in the context of developing a novel aphid control strategy based on the use of aphid sex pheromones to manipulate parasitoid populations.

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50

Walton, M. P. "The application of gel-electrophoresis to the study of cereal aphid parasitoids". Thesis, University of Hertfordshire, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.373437.

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