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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.
1

Toxicity of selected acaricides on Tetranychus urticae Koch (Tetranychidae: Acari) and Orius insidiosus Say (Hemiptera: Anthocoridae) life stages and predation studies with Orius insidiosus

Ashley, Janet Lee 12 January 2004 (has links)
Most management tactics for Tetranychus urticae (TSSM) rely upon applying acaricides. Multiple applications are required, which impact natural enemies. Growers will benefit from a more complete understanding of acaricide toxicity. My objectives were to determine: 1.) stage-specific direct and residual efficacy of three acaricides to TSSM; 2) direct and residual toxicity of these acaricides to O. insidiosus; 3) the functional response of O. insidiosus to mobile and egg stages of TSSM, in laboratory and greenhouse studies; 4) the abundance of O. insidiosus relative to TSSM densities in peanut. Direct toxicity of three acaricides to TSSM was measured on peanut cuttings. All acaricides caused significant mortality, however; mortality did not differ among the acaricides. Residual toxicities against TSSM were not found to be toxic compared with untreated controls 24 and 72 hours after treatment. When acaricide toxicity to eggs was tested, the hatch rate for all treatments was significantly lower than the control hatch rate. Direct toxicity of the acaricides was tested against O. insidiosus. Fenpropathrin and propargite caused 100% mortality and etoxazole resulted in mortality > 50%. Residual toxicity of acaricides to O. insidiosus adults varied. Fourteen days after treatment, fenpropathrin left residues highly toxic to O. insidiosus. In laboratory studies, the functional response of O. insidiosus to TSSM eggs resulted in a Type III response whereas the functional response to adults was Type II. The data suggest either a Type II or linear response in greenhouse studies. A definitive conclusion cannot be drawn because of the sample size. / Master of Science
2

Alternative food and learning as a promising strategy for biological control / Alimento alternativo e aprendizagem como uma estratégia promissora para o controle biológico

Bernardo, Ana Maria Guimarães 20 July 2015 (has links)
Submitted by Reginaldo Soares de Freitas (reginaldo.freitas@ufv.br) on 2016-08-10T16:22:27Z No. of bitstreams: 1 texto completo.pdf: 572732 bytes, checksum: 0125422c912a63d0a16a187b21ba0c1c (MD5) / Made available in DSpace on 2016-08-10T16:22:27Z (GMT). No. of bitstreams: 1 texto completo.pdf: 572732 bytes, checksum: 0125422c912a63d0a16a187b21ba0c1c (MD5) Previous issue date: 2015-07-20 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Várias espécies de predadores onívoros são utilizadas no controle biológico. Orius são importantes inimigos naturais onívoros de pragas que afetam hortaliças e plantas ornamentais. A densidade destes predadores em campo pode aumentar com o fornecimento de alimentos alternativos, especialmente quando a presa é escassa. Além disso, é sugerido que predadores podem aprender associar fonte de odores com a presença de alimento, reduzindo o tempo de procura dos inimigos naturais e, consequentemente o número de pragas nas culturas. Com isso, o nosso objetivo foi encontrar alimentos alternativos de baixo custo e estudar a capacidade de aprendizagem do predador Orius insidiosus. Foi, portanto, avaliado a performance do predador O. insidiosus em quatro alimentos alternativos: pólen de Ricinus sp., pólen de abelha, ácaros detritívoros Tyrophagus putrescentiae e ovos de Anagasta kuehniella. Além disso, utilizou-se salicilato de metila sintético (MeSa) e óleo de menta como fontes de odores para estudar a capacidade de aprendizagem do predador. O predador apresentou uma melhor performance quando alimentava-se de A. kuehniella ou T. putrescentiae. Quando o predador associou alimento com a fonte de odor eles não mostraram preferência para óleo de menta, mas mostraram preferência para MeSa. No entanto, quando o odor era associado com ausência de alimento os predadores foram repelidos pelo óleo de menta e não houve atração ou repelência para MeSa. Estes resultados indicam que alimentos alternativos e de baixo custo (T. putrescentiae) podem ser utilizados com o objetivo de sustentar a população do predador em criações massal e, possivelmente, em culturas. Adicionalmente, nossos resultados mostram que O. insidiosus é capaz de aprender, mas essa capacidade de aprendizagem dos predadores varia com o composto volátil testado. / Several species of omnivorous predators are used in the biological control. Omnivorous predatory bugs are important natural enemies of pest that affect crops in greenhouse. It has been suggested that the use of alternative foods promote the establishment of predators on crops. Moreover, some research propose that predators can learn to associate chemical compounds with presence of food, so reducing the time of searching of natural enemies and number of pest on crops. Our aim was to find cheaper alternative foods and investigate learning ability of the predator Orius insidiosus. We evaluated the performance of O. insidiosus on four alternative foods: Ricinus sp. pollen, bee pollen, the acarid prey Tyrophagus putrescentiae and eggs of Anagasta kuehniella. Furthermore, we used synthetic methyl salicylate (MeSa) and mint oil as odour sources to study the learning ability of this predator. The predatory bugs demonstrated a better performance when fed A. kuehniella or T. putrescentiae. Our results showed that when the predator had to associate odour sources with presence of food, they showed no preference to mint oil, but showed a preference to MeSa. In addition, when the predator had to associate odour sources without food, they showed a preference to mint oil, but did not show a preference to MeSa. These results reveal that alternative and cheaper foods (e.g. T. putrescentiae) can be used with aim to sustain the predator population on rearings and possibly in crops. In addition, our results showed that O. insidiosus is able to learn, but this learning ability of predators varies with volatile compounds.
3

New Strategies to Improve the Efficiency of the Biological Control Agent, Orius insidiosus (Say), in Greenhouse Ornamental Crops

Waite, Meghann Olivia 02 January 2013 (has links)
This thesis investigated new strategies to increase both the control and cost efficiency of the biological control agent, Orius insidiosus Say (Orius), in greenhouse ornamental crops through the identification of an optimal banker plant species, a suitable source of supplemental food, and the identification of an attractive semiochemical lure. Seven plant species/cultivars were evaluated in laboratory and greenhouse bioassays to determine if the plants could provide: an acceptable food source; a location for oviposition; high nymphal survival and rapid development to the adult stage; and a host plant for sustainable population growth. Based on the results obtained overall, the Purple Flash ornamental pepper is the best candidate for use as a banker plant. Greenhouse and laboratory bioassays investigated the suitability of various supplemental food sources. In greenhouse trials, cattail pollen did not sustain a population of Orius on chrysanthemum plants but did significantly increase the population of the target pest, the western flower thrips. The addition of Ephestia kuehniella eggs or honeybee-collected pollen can increase the production of Orius on Purple Flash banker plants. Orius females fed on E. kuehniella eggs or honeybee-collected pollen laid the greatest numbers of eggs and lived significantly longer compared to those fed apple pollen, cattail pollen, corn pollen in laboratory bioassays. In laboratory olfactory assays and greenhouse release experiments, Orius showed the greatest response to olfactory cues associated with a neryl (S)-2-methylbutanoate lure over odours emitted from a methyl salicylate lure, a methyl isonicotinate lures or clean air. / OMAFRA-University of Guelph research partnership, OMAFRA-Highly Qualified Personnel (HQP) Scholarship Program, and MITACS Accelerate.
4

Aspectos biológicos de Orius insidiosus (Say, 1832) (Hemiptera: Anthocoridae) alimentado com larvas de Plutella xylostella (Linnaeus, 1758) (Lepidoptera: Plutellidae) criadas em brassicáceas

Pedroso, Elizabeth do Carmo [UNESP] 20 December 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:46Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-12-20Bitstream added on 2014-06-13T18:42:54Z : No. of bitstreams: 1 pedroso_ec_dr_jabo.pdf: 304491 bytes, checksum: bfd448beba5d92c9c2eaf24d085e6a78 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Orius insidiosus é uma espécie generalista, o que o torna apto à exploração do ecossistema. A traça-das-crucíferas, Plutella xylostella, é considerada a principal praga das brassicáceas podendo ocasionar destruição total. Este estudo visou obter informações sobre O. insidiosus para subsidiar o desenvolvimento de programas de controle biológico de P. xylostella em diferentes variedades de brassicáceas. Foram considerados os seguintes objetivos específicos: a) avaliar o desenvolvimento de O. insidiosus; b) confeccionar a tabela de vida de O. insidiosus alimentado com larvas de segundo ínstar de P. xylostella criadas em diferentes variedades de brassicáceas; c) obter a resposta funcional de O. insidiosus. As criações dos insetos (O. insidiosus e P. xylostella) e os experimentos foram desenvolvidos no Laboratório de Biologia e Criação de Insetos (LBCI) da FCAV/UNESP campus de Jaboticabal, sob temperatura de 25±1ºC, umidade relativa de 70±10% e fotofase de 12 horas. Foram mantidas criações de P. xylostella nas seguintes variedades: Brassica oleracea L. var. acephala (couve), var. itálica (brócolis), var. capitata (repolho) e var. botrytis (couve-flor). Oitenta ninfas de primeiro ínstar foram individualizadas em placas de Petri para o acompanhamento da fase ninfal. Os adultos foram separados por sexo, acasalados e mantidos em placas de Petri para a verificação das características reprodutivas e longevidade. Para os estudos de resposta funcional fêmeas foram deixadas sem alimentação por 12h e individualizadas em placas de Petri com larvas nas densidades de 2, 4, 8, 16 e 32 por placa, para cada variedade. A duração média da fase ninfal foi de 11,4; 13,9; 13,0 e 14,1 dias para brócolis, couve, couve-flor e repolho, respectivamente. A longevidade de O. insidiosus não diferiu entre as variedades. O período de pré-oviposição... (Resumo completo, clicar acesso eletrônico abaix / Orius insidiosus is a generalist specie, which makes it suitable to explore the ecosystem. The diamondback moth, Plutella xylostella, is a major pest of Brassicaceae and can cause total destruction to the culture. This study aimed at obtaining information about O. insidiosus for use to develop biological control programs of P. xylostella in different varieties of Brassicaceae. We considered the following specific objectives: a) evaluate the development of O. insidiosus; b) to prepare a life table O. insidiosus fed on second instar larvae of P. xylostella reared on different cultivars of Brassicaceae; c) obtain the functional response of O. insidiosus. The rearing of insects (O. insidiosus e P. xylostella) and the experiments were developed in the Laboratory of Insect Biology and Rearing (LBCI), FCAV / UNESP Jaboticabal, under temperature 25 ± 1 ° C, relative humidity of 70 ± 10% and photophase of 12 hours. It was maintained rearing of P. xylostella in the varieties B. oleracea var. acephala (kale), var. italic (broccoli), var. capitata (cabbage) and var. botrytis (cauliflower). Eighty nymphs of first instar were individually placed in Petri dishes to the accompaniment of the nymphal stage. The adults were sexed, mated and kept in Petri dishes for the verification of reproductive traits and longevity. To study the functional response of females were left without feed for 12 hours and individualized in Petri dishes with caterpillars in the densities of 2, 4, 8, 16 and 32 per plate for each variety. The production of females (R0), generation time (T), intrinsic rate of increase (rm) and longevity of females were similar. O. insidiosus is able to grow and reproduce preying larvae of the diamondback moth in different cultivars of Brassicaceae. The average of the nymphal stage were 11.4, 13.9, 13.0 and 14.1 days for broccoli, cabbage, cauliflower and kale... (Complete abstract click electronic access belo
5

Aspectos biológicos de Orius insidiosus (Say, 1832) (Hemiptera: Anthocoridae) alimentado com larvas de Plutella xylostella (Linnaeus, 1758) (Lepidoptera: Plutellidae) criadas em brassicáceas /

Pedroso, Elizabeth do Carmo. January 2011 (has links)
Orientador: Sérgio Antonio de Bortoli / Banca: Geraldo Andrade de Carvalho / Banca: César Freire Carvalho / Banca: Antonio Carlos Busoli / Banca: Francisco Jorge Cividanes / Resumo: Orius insidiosus é uma espécie generalista, o que o torna apto à exploração do ecossistema. A traça-das-crucíferas, Plutella xylostella, é considerada a principal praga das brassicáceas podendo ocasionar destruição total. Este estudo visou obter informações sobre O. insidiosus para subsidiar o desenvolvimento de programas de controle biológico de P. xylostella em diferentes variedades de brassicáceas. Foram considerados os seguintes objetivos específicos: a) avaliar o desenvolvimento de O. insidiosus; b) confeccionar a tabela de vida de O. insidiosus alimentado com larvas de segundo ínstar de P. xylostella criadas em diferentes variedades de brassicáceas; c) obter a resposta funcional de O. insidiosus. As criações dos insetos (O. insidiosus e P. xylostella) e os experimentos foram desenvolvidos no Laboratório de Biologia e Criação de Insetos (LBCI) da FCAV/UNESP campus de Jaboticabal, sob temperatura de 25±1ºC, umidade relativa de 70±10% e fotofase de 12 horas. Foram mantidas criações de P. xylostella nas seguintes variedades: Brassica oleracea L. var. acephala (couve), var. itálica (brócolis), var. capitata (repolho) e var. botrytis (couve-flor). Oitenta ninfas de primeiro ínstar foram individualizadas em placas de Petri para o acompanhamento da fase ninfal. Os adultos foram separados por sexo, acasalados e mantidos em placas de Petri para a verificação das características reprodutivas e longevidade. Para os estudos de resposta funcional fêmeas foram deixadas sem alimentação por 12h e individualizadas em placas de Petri com larvas nas densidades de 2, 4, 8, 16 e 32 por placa, para cada variedade. A duração média da fase ninfal foi de 11,4; 13,9; 13,0 e 14,1 dias para brócolis, couve, couve-flor e repolho, respectivamente. A longevidade de O. insidiosus não diferiu entre as variedades. O período de pré-oviposição... (Resumo completo, clicar acesso eletrônico abaix / Abstract: Orius insidiosus is a generalist specie, which makes it suitable to explore the ecosystem. The diamondback moth, Plutella xylostella, is a major pest of Brassicaceae and can cause total destruction to the culture. This study aimed at obtaining information about O. insidiosus for use to develop biological control programs of P. xylostella in different varieties of Brassicaceae. We considered the following specific objectives: a) evaluate the development of O. insidiosus; b) to prepare a life table O. insidiosus fed on second instar larvae of P. xylostella reared on different cultivars of Brassicaceae; c) obtain the functional response of O. insidiosus. The rearing of insects (O. insidiosus e P. xylostella) and the experiments were developed in the Laboratory of Insect Biology and Rearing (LBCI), FCAV / UNESP Jaboticabal, under temperature 25 ± 1 ° C, relative humidity of 70 ± 10% and photophase of 12 hours. It was maintained rearing of P. xylostella in the varieties B. oleracea var. acephala (kale), var. italic (broccoli), var. capitata (cabbage) and var. botrytis (cauliflower). Eighty nymphs of first instar were individually placed in Petri dishes to the accompaniment of the nymphal stage. The adults were sexed, mated and kept in Petri dishes for the verification of reproductive traits and longevity. To study the functional response of females were left without feed for 12 hours and individualized in Petri dishes with caterpillars in the densities of 2, 4, 8, 16 and 32 per plate for each variety. The production of females (R0), generation time (T), intrinsic rate of increase (rm) and longevity of females were similar. O. insidiosus is able to grow and reproduce preying larvae of the diamondback moth in different cultivars of Brassicaceae. The average of the nymphal stage were 11.4, 13.9, 13.0 and 14.1 days for broccoli, cabbage, cauliflower and kale... (Complete abstract click electronic access belo / Doutor
6

Bionomics of the anthocorid, Orius insidiosus (Say) in Virginia apple orchards

McCaffrey, Joseph P. January 1981 (has links)
The anthocorid, Orius insidiosus (Say) is a common polyphagous predator in Virginia apple orchards, particularly in orchards under reduced pesticide programs. The purpose of this research was to contribute to the basic knowledge of the biology and ecology of O. insidiosus in Virginia orchards and to evaluate the potential for its incorporation into IPM programs currently being developed. Egg and nymphal development of O. insidiosus was studied at 17°, 23°, 29°, and 35°C. Nymphs were supplied with an excess of the European red mite, Panonychus ulmi (Koch). There was a linear relationship between development rate (l/Days) of O. insidiosus and temperature. Developmental threshold temperatures were calculated as 10.2°C for the eggs; 8.9°, 7.5°, 10.7°, 12.5°, and 9.9°C for nymphal instars 1-5 respectively; and 10.0°C for total nymphal development. Mean degree-days (DD) requirements were 75.8 for eggs; 45.0, 38.0, 27.8, 28.8, and 64.9 for instars 1-5 respectively: 201.7 DD were required for total nymphal development. Nymphal development was also studied using aphids and pollen as food sources. Mean time (days ± S.E.) for total nymphal development at 23°C was 19.0 ± 0.0 with aphids and 20.0 ± 0.5 with pollen. As already mentioned, O. insidiosus is a polyphagous predator. Extensive laboratory and field observations established a number of small, soft-bodied insects and mites as well as the eggs of several lepidoptera are acceptable as prey. O. insidiosus also feeds on other beneficial species including predaceous thrips and mites. O. insidiosus falls prey to a number of other general orchard predators, particularly spiders, chrysopids, and other predaceous Heteroptera. During 1977-1978, the population dynamics of O. insidiosus along with a complex of predators and pests in orchards under three different pesticide programs was studied. O. insidiosus underwent 2-3 generations per year in Virginia orchards, depending on the availability of prey. Adults overwintered in the orchard, but most migrated into the orchard during May-early June from other areas. O. insidiosus first responded to aphid populations, but as this prey became scarce in late June, O. insidiosus fed on the European red mite whose populations were usually building up at that time. This study indicated that O. insidiosus responded numerically to increasing mite densities. Numerous weeds and crops serve as alternate sites for 0. insidiosus populations. Corn and alfalfa are often adjacent to orchards in Virginia and apparently serve as a reservoir for O. insidiosus throughout the season. Thistle (Carduus spp.) harbors large numbers of O. insidiosus which prey on thrips. These natural and cultivated alternate sites may be important to the management of O. insidiosus populations. Since pesticides are an important component of an IPM program for apples, the relative toxicity of 14 compounds (2 rates of each) to adult O. insidiosus was evaluated. Common cover-spray materials, aphicides, miticides, new materials such as synthetic pyrethroids, and fungicides were tested. Generally, O. insidiosus tolerated many of the compounds being considered for use in our developing IPM programs--especially at the lower rates. The functional response of O. insidiosus to densities of the European red mite was studied at 18.3°, 23.9°, 29.4°, and 35.0°C. Prey densities ranged from 5-80 mites/ cage. Mite consumption was recorded during five, three-hour intervals during the day. O. insidiosus did exhibit a functional response and increasing temperatures resulted in increased feeding at most prey densities. The data provided a good fit to both the type-2 and type-3 functional response models. The interspecific interactions of 5th instar O. Insidiosus and 2nd instar larvae of another mite predator, Leptothrips mali (Fitch) was studied in the laboratory. L. mali is a potential prey for O. insidiosus, but has a defensive anal secretion which repels predator attacks. Most contacts between well fed O. insidiosus and L. mali resulted in mutual avoidance. Most attacks by O. insidiosus were unsuccessful, especially if the approach was from the rear. Contact with the thrips' anal secretion resulted in immediate repelling of O. insidiosus with subsequent cleaning activity lasting 1-3 minutes. This study supports earlier work that indicated these two predators were compatible, especially in the presence of another food source such as the European red mite. / Ph. D.
7

Ecologia química no controle biológico de fitófagos e respectivos predadores e parasitoides / Chemical ecology on the biological control of phytophagous insects and its predators and parasitoids

Fraga, Diego Felisbino [UNESP] 22 February 2016 (has links)
Submitted by DIEGO FELISBINO FRAGA null (diegofraga@fazu.br) on 2016-03-08T21:00:47Z No. of bitstreams: 1 Tese_Diego_Felisbino_Fraga.pdf: 1816202 bytes, checksum: 645838702bb204f2d81827bcc74d32f0 (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-03-09T18:05:33Z (GMT) No. of bitstreams: 1 fraga_df_dr_jabo.pdf: 1816202 bytes, checksum: 645838702bb204f2d81827bcc74d32f0 (MD5) / Made available in DSpace on 2016-03-09T18:05:33Z (GMT). No. of bitstreams: 1 fraga_df_dr_jabo.pdf: 1816202 bytes, checksum: 645838702bb204f2d81827bcc74d32f0 (MD5) Previous issue date: 2016-02-22 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / O Controle Biológico Natural, ou Conservativo, é uma ferramenta indispensável para o sucesso do Manejo Integrado de Pragas, pois permite uma interação entre os componentes do ambiente, o que o coloca na linha de frente das táticas e estratégias de manejo de pragas em agroecossistemas. Basicamente, esta interação, denominada interação tritrófica, envolve as plantas, os organismos fitófagos e seus inimigos naturais. Neste contexto, diversos fatores são importantes para o controle biológico, tais como condições abióticas e bióticas, destacando-se características das plantas (compostos metabólitos secundários e arquitetura, por exemplo) e potenciais presas/hospedeiros (semioquímicos, etc.). Inimigos naturais podem utilizar estes recursos durante o seu processo de busca e localização do hospedeiro, de modo que o conhecimento sobre o comportamento de inimigos naturais em função da fenologia e arquitetura das plantas, bem como sobre o potencial de voláteis emitidos por plantas e presas é fundamental para um programa de manejo integrado de pragas. Desta forma, o presente trabalho teve por objetivos: a) avaliar a dinâmica populacional e a distribuição vertical de ovos de Chrysodeixis includens (Lepidoptera: Noctuidae) e de seus ovos parasitados por Trichogramma spp. (Hymenoptera: Trichogrammatidae) na cultura da soja; b) determinar a resposta comportamental do percevejo predador Orius insidiosus (Hemiptera: Anthocoridae) para voláteis associados à Halyomorpha halys (Hemiptera: Pentatomidae). Sendo assim, em Jaboticabal, SP, Brasil, durante as safras agrícolas de 2012/13 e 2013/14, foram realizadas coletas de ovos de C. includens presentes em diferentes terços das plantas de soja, durante diferentes estádios fenológicos da cultura. Semanalmente, o número de ovos presentes nas plantas foi anotado e os mesmos eram coletados e levados para laboratório para aguardar a emergência de lagartas ou de adultos de Trichogramma spp. O número de adultos do parasitoide emergido por ovo era registrado, bem como a razão sexual. Os adultos foram identificados ao nível específico, encontrando-se a espécie Trichogramma pretiosum presente na cultura da soja. Fêmeas de C. includens preferiram ovipositar com mais intensidade nos terços médio e inferior das plantas, principalmente durante os estádios reprodutivos da cultura. O parasitismo de ovos por T. pretiosum apresentou uma tendência semelhante, em que a medida que se aumentou a densidade de ovos de C. includens nas plantas, também elevou-se o número médio de ovos parasitados, indicando uma forte correlação positiva entre a praga e o inimigo natural. Para atingir o segundo objetivo desta tese, e fornecer alternativas para o controle biológico de H. halys, um pentatomídeo invasor nos EUA, foram conduzidos experimentos para testar a atratividade de O. insidiosus para voláteis emitidos pela presa e por plantas de feijoeiro atacadas por ela. Foram conduzidos experimentos em casa-de-vegetação, laboratório e em campo, em que foi identificado altas concentrações do composto tridecano. Foi avaliado a atratividade de O. insidiosus para diferentes concentrações deste composto, bem como os efeitos desta atração na predação de ovos. Foi observado que O. insidiosus é atraído por tridecano, no entanto, esta atração não afeta a predação de ovos, em casa de vegetação e no campo. / Natural ou Conservative Biological Control is a valuable tool for the success of Integrated Pest Management as it allows a natural interaction between the components of the environment, which places it at the forefront of the tactics and pest management strategies in agroecosystems. This interaction, so-called tritrophic interaction, involves plants, phytophagous organisms and their natural enemies. In this context several factors are important for biological control, such as biotic and abiotic conditions, highlighting plant characteristics (secondary metabolites compounds and plant architecture, for example) and possible prey/hosts (semiochemicals, etc.). Natural enemies can use this information during the its host foraging behavior, so the knowledge of the behavior of natural enemies according to the phenology and plant architecture as well as potential volatiles emitted by prey plants and potential is key for an integrated pest management program. Thus, this study aimed to: a) assess the population dynamics and vertical distribution of natural biological control of Chrysodeixis includens (Lepidoptera: Noctuidae) eggs by Trichogramma spp. (Hymenoptera: Trichogrammatidae) in soybean field; b) determine the behavioral response of the predator Orius insidiosus (Hemiptera: Anthocoridae) for volatile associated with Halyomorpha halys (Hemiptera: Pentatomidae). Thus, in Jaboticabal, SP, Brazil, during the growing seasons of 2012/2013 and 2013/2014, samples were taken from C. includens eggs present on different thirds of soybean plants during different phenological stages of the crop. Weekly, number of eggs present in plants was recorded and the eggs were collected ant taken to the laboratory to await the emergence of larvae or adult Trichogramma spp. The number of adult Trichogramma spp. emerged per egg was noted, as was the sex ratio. The adults were identified to species level, finding Trichogramma pretiosum as the main species present in soybeans. Females of C. includens intensively preferred to lay eggs in the middle and lower thirds of the plants, especially during the reproductive stages of soybean plants. Egg parasitism by T. pretiosum presented a similar tendency, which as the C. includens eggs density increased in plants, also increased the average number of parasitized eggs, indicating a strong positive correlation between the pest and the natural enemy. To achieve the second objective of this thesis, and provide alternatives for the biological control of H. halys (an invasive pentatomid in the US). experiments were conducted to test the attractiveness of O. insidiosus to volatiles emitted by the prey and bean plants attacked by it. Experiments were conducted under greenhouse, laboratory and field conditions. It was identified that tridecane was the major compound in damage-bean pods as well as on H. halys. The attractiveness of O. insidiosus was evaluated for different concentrations of this compound as well as the effects of this attraction as predators of eggs. It was observed that O. insidiosus is attracted to tridecane, however, this attraction not poisitivamente affected the predation of eggs in the greenhouse and in the field. / CNPq: 164869/2014-0

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