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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Biotic interactions in a changing world: the role of feeding interactions in the response of multitrophic communities to rising temperature and nitrogen deposition

De Sassi, Claudio January 2012 (has links)
Global warming and increasing atmospheric nitrogen deposition are ranked as second and third most important global drivers of biodiversity loss. Widespread species losses have deep implications for the functioning of ecosystems, the delivery of essential ecosystem services and their resilience to future environmental perturbations. There is growing recognition that interactions between species play a crucial role in determining the response of ecosystems to global environmental changes. Moreover, evidence of synergistic effects between global change drivers has prompted numerous calls to integrate multiple drivers in ecological research. Nevertheless, empirical studies assessing the impacts of temperature and nitrogen on communities at multiple trophic levels are largely absent. This thesis explores the effects of temperature and nitrogen on a tri-trophic system comprising plants, herbivores and natural enemies. The first chapter shows impacts of the drivers on the composition and phenology of an herbivore community. The second chapter highlights changes in biomass under the treatments at three trophic levels. The third chapter explores, for the first time, the impacts of temperature and nitrogen on quantitative food webs. Finally, the last data chapter uses body size as an important species trait to gain insights on the mechanisms causing shifts in food web structure. The key findings of this thesis were i) trophic interactions largely mediated the effects of both global change drivers ii) In particular, strong bottom-up effects determined the system response, with herbivores responding positively and consistently more so than plants and parasitoids in particular. However, iii) this contrasting response was not explained by a phenological mismatch. iv) Food-web structure responded to the changes in composition of herbivores and parasitoids, but shifts in interaction structure did not affect the resilience of the food. However, temperature and nitrogen impacted host-parasitoid food-web structure by altering the response of parasitoid species to host density and size structuring, which is likely to bear consequences on host-parasitoid co-evolution and future food-web architecture and stability. Finally, v) we found frequent, non-additive interactions between the global change drivers. We conclude that co-occurring temperature and nitrogen are likely to alter food-web structure and overall ecosystem balance, with increasing herbivore dominance likely to have important implications for ecosystem functioning and food-web persistence.
52

Investigations on the natural control of cereal aphids by predators and parasitoids in spring barley in Ethiopia and winter wheat in Germany /

Mamo, Adisu Berhan. January 2003 (has links)
Thesis (doctoral) - Humboldt-Univ., Berlin, 2003. / Includes bibliographical references.
53

Fontes de carboidratos para Palmistichus elaeisis Delvare & LaSalle (Hymenoptera: Eulophidae) / Sources of carbohydrates to Palmistichus elaeisis Delvare & LaSalle (Hymenoptera: Eulophidae)

Dimaté, Francisco Andres Rodríguez 05 December 2012 (has links)
Made available in DSpace on 2015-03-26T13:30:45Z (GMT). No. of bitstreams: 1 texto completo.pdf: 480748 bytes, checksum: ce31c7359ed167f178071ba30f0eafe0 (MD5) Previous issue date: 2012-12-05 / Adults parasitoid feed on sugar rich sources such as floral nectar and honeydew sources and these can increase the potential for control of these natural enemies. Palmistichus elaeisis Delvare & LaSalle (Hymenoptera: Eulophidae) is a generalist endoparasitoid of Lepidoptera and Coleoptera pests. The reproductive parameters and longevity of P. elaeisis were evaluated using different sources of carbohydrate (fructose, glucose, sucrose, mixture of sucrose + glucose + fructose, and honey,) all these sugars were 99% pure and 1M concentration solutions were made with distilled water. The carbohydrate source did not affect the life cycle and progeny emerged, but affected the sex ratio of P. elaeisis. However, this parasitoid showed a higher proportion of females than males with all diets, which is desirable in biological control programs. The lowest values of parasitism (85%) mixture with honey and fructose + sucrose + glucose did not affect the percentage of emergence of P. elaeisis. The longevity of males was similar with all the sources, the female longevity with the sources of fructose, sucrose, glucose and fructose + sucrose + glucose were significantly higher than honey. These carbohydrate sources can be used in mass rearing of the parasitoid, being the most appropriate source financially honey. The longevity of P. elaeisis females was affected by the carbohydrate source showing that honey, though it can be used for mass rearing for increased longevity is required the availability of sources such as fructose, sucrose, glucose and fructose + glucose + sucrose. / Parasitoides adultos alimentam-se de fontes ricas em açúcar como néctar floral e honeydew e essas fontes podem aumentar o potencial de controle destes inimigos naturais. Palmistichus elaeisis Delvare & LaSalle (Hymenoptera: Eulophidae) é um endoparasitoide generalista de Lepidoptera e Coleoptera praga. Os parâmetros reprodutivos e a longevidade de P. elaeisis foram avaliados com diferentes fontes de carboidrato (frutose, glicose, sacarose, mistura de frutose + glicose + sacarose, e mel) fornecidas à uma concentração de 1M e pureza de 99% para esse parasitoide. A fonte de carboidrato não afetou o ciclo de vida e a progênie emergida, mas afetou a razão sexual de P. elaeisis. No entanto, esse parasitoide apresentou maior proporção de fêmeas que machos com todas as fontes, o que é desejável em programas de controle biológico. Os menores valores de parasitismo (85%) com mel e a mistura frutose + glicose + sacarose não afetaram a porcentagem de emergência de P. elaeisis. A longevidade de machos foi semelhante com todas às fontes, nas fêmeas a longevidade com as fontes de frutose, sacarose, glicose e frutose + glicose + sacarose foram significativamente maiores que o mel. Estas fontes de carboidrato podem ser utilizadas na criação massal do parasitoide, sendo a fonte mais adequada financeiramente o mel. A longevidade das femeas de P. elaeisis foi afetada pela fonte de carboidrato mostrando que a mel, embora, possa ser utilizada na criação massal, não é recomendável na longevidade, porem devem ser fornecidas fontes como frutose, sacarose, glicose e frutose + glicose + sacarose para aumento da longevidade.
54

Etude du mode de production de l'ADN des particules du bracovirus dans la guêpe parasitoïde Cotesia congregata / Study about the production mechanism of the DNA encapsidated in bracovirus particle in the parasitoid wasp Cotesia congregata

Louis, Faustine 25 June 2013 (has links)
Les bracovirus forment une symbiose avec les guêpes parasitoïdes, demeurant dans leur génome et produits uniquement dans leurs ovaires. Nous avons caractérisé comment les cercles d’ADNdb contenu dans les particules étaient amplifiés depuis leur forme provirale avant leur encapsidation.Nous avons montré que le site d’intégration du génome viral est conservé chez les bracovirus et organisé dans le génome de la guêpe en un macrolocus regroupant la majorité des segments proviraux et 7 loci isolés. Nous avons mis en évidence 12 unités de réplication (UR) et que les 9 gènes viraux du cluster nudiviral étaient amplifiés sur une UR sans être encapsidés. Nous avons identifié des concatémères tête-tête et queue-queue comme étant les intermédiaires de réplication des UR, caractéristiques d’une réplication linéaire du génome viral. Enfin, nous avons montré que l’ADN polymérase B2 appartenait à un élément Maverick. L’absence de gènes viraux de la réplication du génome viral semble indiquer que la machinerie réplicative cellulaire serait impliquée. Il reste maintenant à mettre en évidence les différents facteurs cellulaires participant à l’amplification du génome viral. / Bracovirus form a symbiosis with parasitoid wasp, remaining in their genome and products only in their ovaries. We characterized how packaged dsDNA circles were amplified from their proviral genome before packaging in viral particles.We showed that viral genome integration site is conserved in bracovirus and organized in the wasp genome in a macrolocus where the majority of proviral segments was found and 7 isolated loci. We showed 12 replication units (UR) and the 9 nudiviral genes from cluster were amplified on a UR without being packaged. We identified concatemers head-head and tail-tail as the replication intermediates of UR, indicating a linear replication of the viral genome. Finally, we showed that DNA polymerase B2 belonged to a Maverick element.The absence of viral gene involved in the genome replication suggests that the cellular replication machinery is involved. It remains to highlight the different cellular factors involved in the amplification of the viral genome.
55

Ecologia comportamental e diversidade em um sistema hospedeiro-parasitóide : vespas parasitóides de Schismatodiplosis lantanae Rübsaamen, 1916 (Cecidomyiidae) em Lantana camara L. (Verbenaceae)

Dell'Aglio, Denise Dalbosco January 2012 (has links)
Este estudo investigou a ecologia de vespas parasitóides ocorrentes em galhadores Schismatodiplosis lantanae Rübsaamen, 1916 (Cecidomyiidae) em folhas de Lantana camara L. (Verbenaceae). Dessa forma, o primeiro artigo trata da ecologia comportamental da vespa parasitóide Torymus sp. (Torymidae, Hymenoptera), onde foi avaliado como as fêmeas dessa espécie defendem seu recurso de oviposição no hospedeiro. Foi analisado mudanças no comportamento devido à presença de outra fêmea coespecífica no local, ser residente do recurso, tamanho das vespas e número e tamanho das galhas através de filmagens dos experimentos realizados em laboratório. Com esse trabalho observou-se que fêmeas mudam seu comportamento quando estão na presença de um competidor em um território com hospedeiros. A estratégia de ataque foi através da ameaça, na qual suas antenas e asas são levantadas para expulsar o competidor do local. A probabilidade de haver ataques a fêmeas coespecíficas depende do tempo prévio de exploração da galha e da permanência na folha. O interesse no hospedeiro pelas invasoras foi a principal causa de conflitos com a residente. O segundo artigo trata da diversidade de vespas parasitóides e de um ciclo parasita-hospedeiro observado no período de um ano no sistema de L. camara. Foram encontradas nove espécies de vespas parasitóides, divididas em quatro famílias. Ocorreu um ciclo no parasitismo das espécies de vespas sobre seu hospedeiro no ano amostrado, podendo ser observado que são mais elevadas nos meses de Julho a Janeiro e a sobrevivência do hospedeiro foi maior nos meses de Fevereiro a Maio. As estratégias comportamentais de fêmeas de uma vespa parasitóide em relação a seus hospedeiros foram analisadas, bem como um sistema composto de diversas espécies parasitóides e sua variação no tempo. Estas observações podem contribuir para um melhor entendimento da ecologia comportamental e do padrão temporal das vespas parasitoides, e também para futuros programas de controle biológico mais eficientes. / We investigated the ecology of parasitoid wasps attacking Schismatodiplosis lantanae Rübsaamen, 1916 (Cecidomyiidae) galls on leaves of Lantana camara L. (Verbenaceae). The first article discusses the behavioral ecology of the parasitoid wasp Torymus sp. (Torymidae, Hymenoptera), reporting how their females defend oviposition resources on the hosts, changing their behavior due to the presence of a conspecific female in the patch. The identity of the wasp (resident or intruder) on the resource, female size and number and size of galls in the patch were factors studied through analysis of the behaviors revealed by video recordings of the laboratory experiments. Females change their behavior in the presence of a competitor in a territory with hosts. The strategy was to threat, raising their antennae and wings to expel the competitor of the patch. The probability of an attack on a conspecific females depended on the host exploitation time and time spent on the galled leaf. Interest in host by intruders was the main cause for conflicts. The second article reports the diversity of parasitoid wasps and a host-parasite cycle during one year period in the L. camara leaf galls system. Nine parasitoid wasp species were found, divided in four families. A cycle between parasitism and host survival was found during the sampling period. Wasp species are more abundant from July to January and host survival higher from February to May. Behavioral strategies of parasitoid wasp females toward their hosts and conspecifics have been elucidated, with the system composed of different parasitoid wasp species apparently going through an annual cycle of parasitism rate. These observations may contribute to a better understanding of parasitoid behavioral ecology and host-parasitoid dynamics, enabling more efficient future biological control programs.
56

Evoluce hostitelské specializace blanokřídlých parazitoidů rodu Torymus / Evolution of parasitic Hymenoptera hosts specialisation of the genus Torymus

Bubeníková, Kristýna January 2018 (has links)
The genus Torymus (Chalcidoidea: Torymidae) has very diversified parasitic strategies and adaptations to its hosts. Its larvae are ectoparasitoids and attack mostly larvae of various gall wasps (Hymenoptera: Cynipidae) and gall midges (Diptera: Cecidomyiidae). However, few species prefer also other insect groups as a host or are even phytophagous. Many hypotheses concerning evolution of insect host associations were published, but have not been satisfactorily tested using parasitic insects as a model. In this thesis I studied coevolution of the genus Torymus and its hosts. The main questions are what kind of host shifts occurred during the evolution of host strategies and whether sister species of parasitoids are specific to the related hosts/or nonrelated hosts living in the same type of habitat. I also studied changes at morphological adaptations to its hosts. To test critically these hypotheses, I constructed phylogenetic tree of selected Torymus species based on 5 genes and compared their host association within and between clades of Torymus. Key words: Torymus, Chalcidoide, parasitoid, phylogeny, host specialisation
57

Avaliação da qualidade de produção e de busca pelo hospedeiro de Cotesia flavipes (Cameron) (Hymenoptera: Braconidae) em laboratório

Viel, Silvio Rogério [UNESP] 21 December 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:46Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-12-21Bitstream added on 2014-06-13T20:02:57Z : No. of bitstreams: 1 viel_sr_dr_jabo.pdf: 828115 bytes, checksum: b974e906f04ebb44b4d4434000bd82f4 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Visando melhorias qualitativas na criação de Cotesia flavipes Cameron, 1891, realizaram-se testes com alimentação de adultos antes do parasitismo em Diatraea saccharalis Fabricius,1794, com 14 dietas: (2,5%; 5% e 10% sacarose; 2,5%; 5% e 10% sacarose + 2,5% lêvedo de cerveja; 2,5%; 5% e 10% mel; 2,5%; 5% e 10% mel + 2,5% lêvedo de cerveja; 2,5% lêvedo de cerveja; água) e testemunha. Avaliaramse: adultos emergidos, razão sexual, porcentagem de emergência, peso das massas de pupas e a longevidade nas gerações F1 e F2. O delineamento foi o inteiramente casualizado com 15 tratamentos e cinco repetições. As dietas a base de 5% de sacarose, 5 e 10% de mel aos adultos de C. flavipes podem proporcionar acréscimo considerável na longevidade dos parasitoides. O consumo de dietas artificiais por C. flavipes antes do parasitismo em D. saccharalis proporcionou melhorias qualitativas. O estudo visou ainda testar um protocolo de qualidade de C. flavipes, quanto à eficiência na busca pelo hospedeiro D. saccharalis. Foi usada uma arena de testes (copo plástico translúcido de 700 mL, com tampa). Lagartas de D. saccharalis foram colocadas em tolete de cana-de-açúcar de 13 cm, perfurado transversalmente e oferecidas ao parasitoide. Os tratamentos foram: (0, 6, 12, 18 e 24 horas de fotofase - L), (6, 12, 18 e 24 horas de disponibilidade do hospedeiro - H), (1, 2, 3, 4 e 5 lagartas por arena - T) e o orifício de entrada da lagarta na cana-de-açúcar (aberto - A ou fechado - F). Foram realizados os testes de Kolmogorov e a homogeneidade da variância foi analisada pelo teste de Bartlett, além das análises de agrupamento e de componentes principais. Foi criado um Índice de performance da qualidade (IPQ), que foi determinante na escolha do melhor tratamento. Foi proposto, o uso do tratamento: 6 horas de disponibilidade... / Aiming at qualitative improvements in the rearing of Cotesia flavipes, tests were carried out with adults feed before parasitism in Diatraea saccharalis, with 14 diets (2.5%, 5% and 10% sucrose, 2.5%, 5% and 10% sucrose + 2.5% brewer's yeast, 2.5%, 5% and 10% honey, 2.5%, 5% and 10% honey + 2.5% yeast, 2.5% yeast, water) and control. Were evaluated: emerging adults, sex ratio, percentage of emergency, mass weight of pupae, and longevity in F1 and F2 generations. The design was completely randomized with 15 treatments and five repetitions. The diets based on 5% sucrose, 5 and 10% honey to adults of C. flavipes, may provide considerable increase in longevity. Consumption of artificial diets by C. flavipes before parasitism in D. saccharalis provides quality improvements. The study also aimed to test a protocol for quality of C. flavipes, for efficiency in the search for host D. saccharalis. We used a testing arena (700 mL plastic cup with lid). Larvae of D. saccharalis were placed in 13 cm cutting canes, drilled across, and offered to the parasitoid. The treatments were: (0, 6, 12, 18 and 24 hours of photophase - L) (6, 12, 18 and 24 hours of availability of the host - H) (1, 2, 3, 4 and 5 larvae per arena - T) and the entrance hole of the larvae in sugar cane (open - A or closed - F). We performed the Kolmogorov´s test and the homogeneity of variance was analyzed by Bartlett's test. Were also carried out cluster analysis and principal components. It created an index of performance quality (IPQ). It is proposed the use of treatment 6 hours of availability, 0 hours of light, one larvae per arena, using the cutting cane with the hole closed, as quality protocol C. flavipes
58

Efeito da temperatura e de hospedeiros no desenvolvimento de Diaeretiella rapae (McIntosh) (Hymenoptera: Braconidae, Aphidiinae)

Silva, Robson José da [UNESP] 27 June 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:05Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-06-27Bitstream added on 2014-06-13T20:22:57Z : No. of bitstreams: 1 silva_rj_dr_jabo.pdf: 999654 bytes, checksum: 9b9706815aad595ba6fd6e0dea74a998 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O parasitoide Diaeretiella rapae (McIntosh) é considerado um importante inimigo natural de pulgões em culturas de brassicáceas, apresentando potencial como agente de controle biológico desses insetos-praga. O presente estudo visou obter informações sobre D. rapae para subsidiar o desenvolvimento de programas de controle biológico de pulgões em cultivos de brassicáceas. Foram considerados os seguintes objetivos específicos: a) avaliar a qualidade hospedeira de Myzus persicae (Sulzer), Lipaphis erysimi (Kaltenbach) e Brevicoryne brassicae (L.); b) determinar as exigências térmicas; c) determinar as tabelas de vida de fertilidade em diferentes temperaturas e d) avaliar o efeito do armazenamento à baixa temperatura. Para condução dos experimentos e criação das espécies de pulgões e parasitoide utilizaram-se plantas de couve-manteiga (Brassica oleracea var. acephala) Da Geórgia. A qualidade hospedeira foi investigada utilizando-se câmara climatizada regulada a 25 ± 1ºC, 60 ± 10% UR e 12 horas de fotofase e considerando-se as seguintes variáveis biológicas de D. rapae: parasitismo, períodos de desenvolvimento, porcentagem de emergência de adultos, razão sexual, longevidade e tamanho. As exigências térmicas e tabelas de vida de fertilidade foram determinadas em câmaras climatizadas reguladas a 15, 20, 25 e 30 ± 1 ºC, 60 ± 10% UR e 12 horas de fotofase. Para o armazenamento à baixa temperatura utilizou-se câmara climatizada sob temperatura constante de 5 ± 1°C nos seguintes períodos: 0, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 28, 30, 32, 34 e 36 dias. Entre as espécies de pulgões estudadas M. persicae foi a que proporcionou maior qualidade a D. rapae. O limite térmico inferior de desenvolvimento (Tb) e a constante térmica (K) do parasitoide foram 4,0°C e 245,3 GD, respectivamente. A temperatura afetou o desempenho reprodutivo de D. rapae, sendo 25°C... / The parasitoid Diaeretiella rapae (McIntosh) is considered an important natural enemy of aphids in Brassicaceae, showing potential as a biological control agent of insect pests. This study aimed at obtaining information about D. rapae to subsidize the development of programs for biological control of aphids in Brassicaceae. Were considered the following specific objectives: a) to assess the host quality Myzus persicae (Sulzer), Lipaphis erysimi (Kaltenbach) and Brevicoryne brassicae (L.), b) to determine the thermal requirements, c) to determine the fertility life tables at different temperatures and d) to evaluate the effect of storage at low temperature. The experiments and rearing of parasitoid and aphid species were conducted using cabbage plants (Brassica oleracea var. acephala) Da Geórgia. The host quality was investigated using climate chamber at 25 ± 1 º C, 60 ± 10% RH and 12 h photophase and considering the following biological variables of D. rapae: parasitism, developmental periods, percentage of adult emergence, sex ratio, longevity and size. The thermal requirements and fertility life tables were determined in climatic chambers at 15, 20, 25 and 30 ± 1 º C, 60 ± 10% RH and 12 hours photophase. The storage at low temperature was determined under constant temperature of 5 ± 1 ° C in the following periods: 0, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 28, 30, 32, 34 and 36 days. Among the aphid species studied M. persicae showed high quality to D. rapae. The lower thermal threshold (Tb) and thermal constant (K) of the parasitoid were 4.0 °C and 245.3 GD, respectively. The temperature affected the reproductive performance of D. rapae, 25 ° C provided the best thermal conditions for the population growth of the specie. The storage of D. rapae at 5 °C for up to 32 days does not negatively affect the emergence and survival. The storage up to 36 days did not influence... (Complete abstract click electronic access below)
59

Bioecologia do parasitoide Cleruchoides noackae (Hymenoptera: Mymaridae) em ovos de Thaumastocoris peregrinus (Hemiptera: Thaumastocoridae) / Bioecology of parasitoide Cleruchoides noackae (Hymenoptera: Mymaridae) in eggs of Thaumastocoris peregrinus (Hemiptera: Thaumastocoridae)

Becchi, Luciane Katarine [UNESP] 14 July 2017 (has links)
Submitted by LUCIANE KATARINE BECCHI null (luciane.becchi@hotmail.com) on 2017-10-04T11:36:12Z No. of bitstreams: 1 Dissertação final LUCIANE.pdf: 1506577 bytes, checksum: 7466cc527263feec458778405126fce6 (MD5) / Approved for entry into archive by Monique Sasaki (sayumi_sasaki@hotmail.com) on 2017-10-04T17:35:11Z (GMT) No. of bitstreams: 1 becchi_lk_me_bot.pdf: 1506577 bytes, checksum: 7466cc527263feec458778405126fce6 (MD5) / Made available in DSpace on 2017-10-04T17:35:11Z (GMT). No. of bitstreams: 1 becchi_lk_me_bot.pdf: 1506577 bytes, checksum: 7466cc527263feec458778405126fce6 (MD5) Previous issue date: 2017-07-14 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O percevejo-bronzeado, Thaumastocoris peregrinus Carpintero & Dellapé, 2006 (Hemiptera: Thaumastocoridae), nativo da Austrália, está presente no Brasil desde 2008. De forma agregada, a distribuição e disseminação do percevejo-bronzeado foi rápida nos estados produtores de eucalipto, sendo relatado causando danos em plantios em 14 estados brasileiros. Em 2012, o parasitoide de ovos Cleruchoides noackae Lin & Huber, 2007 (Hymenoptera: Mymaridae) foi introduzido no país, para criação massal em laboratório e liberação à campo, para o controle biológico da população do percevejo-bronzeado. No entanto, ainda há poucos estudos de biologia e comportamento de C. noackae e da dinâmica entre o parasitoide e o hospedeiro. O objetivo foi determinar as exigências térmicas e duração do desenvolvimento de C. noackae, em ovos de T. peregrinus, em diferentes temperaturas; avaliar o parasitismo de ovos de T. peregrinus, por C. noackae em diferentes temperaturas, e estudar, em condições de laboratório, o comportamento de corte, acasalamento e oviposição e o parasitismo de fêmeas virgens e acasaladas de C. noackae em ovos de T. peregrinus. A temperatura, influenciou o tempo de desenvolvimento de C. noackae, notando-se redução do período ovo-adulto com o aumento da temperatura. Fêmeas e machos do parasitoide necessitam de temperaturas acima de 7,34°C e 7,59°C e acúmulo de 298,50 e 289,85 graus-dia, respectivamente, para completar o desenvolvimento. A viabilidade de emergência foi também, afetada pela temperatura, com 20% de parasitoides retidos (não emergidos) a 30ºC. A temperatura influenciou, o parasitismo de C. noackae em ovos de T. peregrinus. Temperaturas entre 21 e 27ºC foram as melhores para o parasitismo de C. noackae em ovos de T. peregrinus, com maior taxa de parasitismo nas primeiras 24 horas. No estudo comportamental de C. noackae, não foi observado comportamento de côrte e ocorre apenas uma cópula entre o casal. Fêmeas virgens e copuladas encontraram o primeiro hospedeiro em 15,21 e 17,14 minutos e os demais em 3,85 e 0,86 minutos, respectivamente. O tempo de forrageamento e inserção do ovipositor de fêmeas virgens e copuladas C. noackae em ovos de T. peregrinus, foi de 24 e 21 segundos e de 5,13 e 3,69 minutos, respectivamente. Fêmeas virgens e copuladas inseriram o ovipositor com maior frequência nas laterais e opérculo do ovo de T. peregrinus. Em uma hora, mais de 50% dos ovos de T. peregrinus oferecidos às fêmeas de C. noackae foram parasitados, indicando alto e rápido parasitismo. A razão sexual de 0,00 (fêmeas virgens) e 0,68 (fêmeas copuladas) confirmam a partenogênse arrenótoca de C. noackae. Fêmeas virgens e copuladas de C. noackae tem capacidade semelhante de parasitismo em laboratório, 89%, porém, a viabilidade de emergência do parasitoide é menor para fêmeas copuladas. Os resultados apresentados neste trabalho podem ser utilizados para o ajuste de técnicas de criação massal em laboratório deste parasitoide e manejo do percevejo-bronzeado. / The bronze bug Thaumastocoris peregrinus Carpintero & Dellapé, 2006 (Hemiptera: Thaumastocoridae) is an eucalypt sap-sucking, native of Australia, present in Brazil since 2008. Its distribution and dissemination, in aggregate form, was fast in the producing states of eucalyptus, being reported causing damages in plantations in 14 states Brazilians. In 2012, the parasitoid of eggs Cleruchoides noackae Lin & Huber, 2007 (Hymenoptera: Mymaridae) was introduced in the country for laboratory mass-rearing and release into the field for the biological control of the population of the bronze bug. However, there are few studies on a C. noackae biology and behavior and dynamics between the parasitoid and its host. The objective was to determine the thermal requirements and the duration of C. noackae development in eggs of T. peregrinus at different temperatures; to evaluate the parasitism of C. noackae in T. peregrinus eggs at different temperatures and to study, under laboratory conditions, the parasitoid courtship, mating and oviposition behaviour and the parasitism of virgin and mated females of C. noackae on T. peregrinus eggs. The temperature, influenced the development time of C. noackae, observing reduction of the biological cycle (egg-adult) with the increase of the temperature. Females and males of the parasitoid require temperatures above 7.34°C and 7.59°C and accumulation of 298.50 and 289.85 degrees day, respectively, for their development. The viability of emergence was affected by temperature with 20% of parasitoids retained (not emerged) at 30ºC. The temperature also influenced the parasitism of C. noackae in T. peregrinus eggs. Temperatures ranging from 21 to 27ºC were better for the parasitism of C. noackae in eggs of T. peregrinus with the highest rate of parasitism occurs within the first 24h. In the behavioral study of C. noackae, no courtship behavior was observed and only one copula between the couple occurred. Virgins and copulated females found the first host in 15.21 and 17.14 minutes and the next host in 3.85 and 0.86 minutes, respectively. The foraging time and duration of ovipositor insertion into T. peregrinus eggs was 24 and 21 seconds and 5.13 and 3.69 minutes, respectively. Virgins and copulated females of C. noackae inserted the ovipositor more frequently on the sides of the egg and operculum of the T. peregrinus egg. At one hour, more than 50% of T. peregrinus eggs offered to C. noackae females were parasitized, indicating high and rapid parasitism. The sex ratio of 0.00 (virgin females) and 0.68 (females copulated) confirming the arrhenotokous parthenogenesis of C. noackae. Female virgins and copulated C. noackae have similar parasitism capacity in the laboratory, 89%, however, the viability of emergence is lower for copulated females. The results presented in this work can be used for adjustment of techniques for parasitoid mass-rearing and bronze bug management.
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Ecologia comportamental e diversidade em um sistema hospedeiro-parasitóide : vespas parasitóides de Schismatodiplosis lantanae Rübsaamen, 1916 (Cecidomyiidae) em Lantana camara L. (Verbenaceae)

Dell'Aglio, Denise Dalbosco January 2012 (has links)
Este estudo investigou a ecologia de vespas parasitóides ocorrentes em galhadores Schismatodiplosis lantanae Rübsaamen, 1916 (Cecidomyiidae) em folhas de Lantana camara L. (Verbenaceae). Dessa forma, o primeiro artigo trata da ecologia comportamental da vespa parasitóide Torymus sp. (Torymidae, Hymenoptera), onde foi avaliado como as fêmeas dessa espécie defendem seu recurso de oviposição no hospedeiro. Foi analisado mudanças no comportamento devido à presença de outra fêmea coespecífica no local, ser residente do recurso, tamanho das vespas e número e tamanho das galhas através de filmagens dos experimentos realizados em laboratório. Com esse trabalho observou-se que fêmeas mudam seu comportamento quando estão na presença de um competidor em um território com hospedeiros. A estratégia de ataque foi através da ameaça, na qual suas antenas e asas são levantadas para expulsar o competidor do local. A probabilidade de haver ataques a fêmeas coespecíficas depende do tempo prévio de exploração da galha e da permanência na folha. O interesse no hospedeiro pelas invasoras foi a principal causa de conflitos com a residente. O segundo artigo trata da diversidade de vespas parasitóides e de um ciclo parasita-hospedeiro observado no período de um ano no sistema de L. camara. Foram encontradas nove espécies de vespas parasitóides, divididas em quatro famílias. Ocorreu um ciclo no parasitismo das espécies de vespas sobre seu hospedeiro no ano amostrado, podendo ser observado que são mais elevadas nos meses de Julho a Janeiro e a sobrevivência do hospedeiro foi maior nos meses de Fevereiro a Maio. As estratégias comportamentais de fêmeas de uma vespa parasitóide em relação a seus hospedeiros foram analisadas, bem como um sistema composto de diversas espécies parasitóides e sua variação no tempo. Estas observações podem contribuir para um melhor entendimento da ecologia comportamental e do padrão temporal das vespas parasitoides, e também para futuros programas de controle biológico mais eficientes. / We investigated the ecology of parasitoid wasps attacking Schismatodiplosis lantanae Rübsaamen, 1916 (Cecidomyiidae) galls on leaves of Lantana camara L. (Verbenaceae). The first article discusses the behavioral ecology of the parasitoid wasp Torymus sp. (Torymidae, Hymenoptera), reporting how their females defend oviposition resources on the hosts, changing their behavior due to the presence of a conspecific female in the patch. The identity of the wasp (resident or intruder) on the resource, female size and number and size of galls in the patch were factors studied through analysis of the behaviors revealed by video recordings of the laboratory experiments. Females change their behavior in the presence of a competitor in a territory with hosts. The strategy was to threat, raising their antennae and wings to expel the competitor of the patch. The probability of an attack on a conspecific females depended on the host exploitation time and time spent on the galled leaf. Interest in host by intruders was the main cause for conflicts. The second article reports the diversity of parasitoid wasps and a host-parasite cycle during one year period in the L. camara leaf galls system. Nine parasitoid wasp species were found, divided in four families. A cycle between parasitism and host survival was found during the sampling period. Wasp species are more abundant from July to January and host survival higher from February to May. Behavioral strategies of parasitoid wasp females toward their hosts and conspecifics have been elucidated, with the system composed of different parasitoid wasp species apparently going through an annual cycle of parasitism rate. These observations may contribute to a better understanding of parasitoid behavioral ecology and host-parasitoid dynamics, enabling more efficient future biological control programs.

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