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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.
221

Criação e bioecologia de Atheloca subrufella (Hulst) (Lepidoptera : Phycitidae) / Creation and bioecology of Atheloca subrufella (Hulst) (Lepidoptera: Phycitidae)

SANTANA, Suêrda Willna Jácome de 04 February 2008 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2016-12-02T12:56:40Z No. of bitstreams: 1 Suerda Willna Jacome de Santana.pdf: 1856490 bytes, checksum: 1b1aa48c4a83323254b5694aeace4c8a (MD5) / Made available in DSpace on 2016-12-02T12:56:40Z (GMT). No. of bitstreams: 1 Suerda Willna Jacome de Santana.pdf: 1856490 bytes, checksum: 1b1aa48c4a83323254b5694aeace4c8a (MD5) Previous issue date: 2008-02-04 / Larvae of coconut moth, Atheloca subrufella (Hulst) (Lep.: Phycitidae), damage flowers and fruits of coconut, Cocos nucifera L., resulting in direct yield reduction. Thus, this work had three major objectives: to develop a feasible rearing methodology for all stages of this pest; to study the biology of A. subrufella reared at 18, 22, 25, 28, 30 and 32ºC and; to investigate the success of A. subrufella larvae colonizing coconut fruits related with the necrosis caused by the coconut mite, Aceria guerreronis Keifer (Acari: Eryophyidae). The rearing technique consisted of using green coconut fruits 10-12 cm of diameter and infested artificially with two to five larvae per fruit. Based on fertility life table parameters estimated for three successive generations, the best results were obtained with two and three A. subrufella larvae reared per fruit. The storage of egg and pupal stages at 12oC can be made upto five days without negative effect on egg viability and adult reproductive output, but storage periods over 10 days affected egg viability and adults’ performance. Developmental period of A. subrufella was reduced as temperature increases and marked effects were found at extreme temperatures of 18 and 32oC. The egg-adult period ranged from 19.3 to 59.8 days from 32ºC to 18ºC, respectively. Developmental viability from egg to adult was 25% at 18 and 32oC, and over 72% at the intermediate temperatures. The lower temperature threshold and thermal requirement for egg-adult period were 12.54oC and 362.75 degree-days, respectively. Basedon thermal requirement, A. subrufella can have 13 generations per year in the Zona da Mata and Sertão areas of Pernambuco State, Brazil. Data from field survey showed that only coconut fruits exhibiting necrosis caused by the coconut mite were infested with A. subrufella larvae. Moths of A. subrufella, however, exhibited similar oviposition preference on damage and undamaged coconut fruits. Neonate larvae and third instar larvae were not able to colonize undamaged coconut fruits. These results support the hypothesis that the necrosis in the coconut fruit caused by early infestation of the coconut mite is a key factor to A. subrufella larvae to colonize the mesocarp of the fruit protected by the fruit perianth. Therefore, the status of coconut fruit key pest of A. subrufella depends on fruit necrosis caused by the coconut mite. / A larva de Atheloca subrufella (Hulst) (Lep.: Phycitidae) ataca flores e frutos do coqueiro, Cocos nucifera L., resultando em perdas diretas na produção. Assim, este trabalho teve três objetivos principais: desenvolver uma técnica de criação para todos as fases de desenvolvimento desta praga; estudar a biologia de A. subrufella nas temperaturas de 18, 22, 25, 28, 30 e 32ºC e; investigar a capacidade da larva em colonizar frutos de coco, relacionado à necrose do ácaro, Aceria guerreronis Keifer (Acari: Eriophyidae). A técnica de criação consistiu no uso de frutos com 10-12 cm de diâmetro infestados artificialmente com duas a cinco larvas por fruto. Baseado nos parâmetros da tabela de vida de fertilidade estimados por três gerações sucessivas, os melhores resultados foram obtidos com duas e três larvas de A. subrufella por fruto. O armazenamento de ovos e pupas a 12oC pode ser feito até cinco dias sem perdas na viabilidade e reprodução dos adultos. No entanto, períodos maiores que 10 dias afetaram a viabilidade dos ovos e o desempenho dos adultos. O período de desenvolvimento de A. subrufella foi reduzido com o aumento da temperatura entre 18 e 30oC. O período ovo-adulto variou de 19,3 a 59,8 dias de 32 a 18ºC, respectivamente. A viabilidade do período ovo-adulto foi de 25% a 18 e 32oC, e acima de 72% nas temperaturas intermediárias. A temperatura base e requerimento térmico de ovo-adulto foram de 12,54oC e 362,75 graus-dias, respectivamente. Baseado nessas exigências térmicas, A. subrufella pode obter até 13 generações por ano na Zona da Mata e Sertão de Pernambuco. Resultados do levantamento de campo mostraram que somente frutos apresentando a necrose do ácaro possuíram infestação de A. subrufella. Mariposas de A. subrufella, no entanto, exibiram similar preferência para a oviposição em frutos com necrose e sem necrose. Larvas neonatas e de terceiro instar foram incapazes de colonizar frutos de coco sem necrose ou injúrias mecânicas. Portanto, estes resultados suportam a hipótese de que a necrose no fruto devido a infestações do ácaro é fator chave para as larvas de A. subrufella colonizarem o mesocarpo protegido pelo perianto dos frutos. Desta forma, o status de praga-chave em fruto de coco, somente ocorre devido à necrose no fruto provocada por A. guerreronis.
222

Impact of different light sources on the responses of moth

Zhou, Yanhe January 2021 (has links)
In recent decades, the negative effects of artificial light at night on natural ecosystems have attracted the attention of ecologists. Studies have shown that artificial light at night leads to a considerable reduction in insects and has a worrying impact on terrestrial ecosystems, including nocturnal insects (e.g. Lepidoptera) such as moths. Warm white light is generally expected to have a lower ecological impact compared with cold white light which has a higher proportion of blue light (< 500 nm). The aim of this study is to investigate the impact of three light emitting diode (LED) light sources with different spectral power distributions on the responses of the greater wax moth (Galleria mellonella) under controlled experimental settings. In this experiment, three light sources with different spectral power distribution and dark condition were used and the start response time, time active, time flap wings, time flap wings / time active, main activity area and stop area of the greater wax moth were investigated. The light treatment used were: (1) darkness (n = 13); (2) warm-white light (correlated color temperature of 2675 K, n = 12); (3) white light (4070 K, n = 4); (4) cold white light (6200 K, n = 8). The experiment was performed in a rectangular light-tight box under controlled conditions. Main activity area showed significant difference between warm-white light and cold white light. With cold white light, a larger proportion of the moths were active in the area with the highest light levels, while the main activity area in the warm white light was in the zone with the lowest light levels. Other variables, however, did not show significant differences. The conclusion is that warm white light had a lower ecological impact than cold white light due to a larger proportion of moth is attracted to areas with stronger light. The results support the notion that in outdoor environments, warm white LEDs (maximum 3000 K) should be preferred compared to cold white light LEDs (over 3000 K), to reduce the impact on insects such as moths. The low correlated color temperature light sources used outdoors deserves more in-depth development and research.
223

THE DEVELOPMENT OF A BIOMEMETIC DYNAMIC AIRFOIL CONTROL SYSTEM FOR FLAPPING WING MICRO AIR VEHICLES

Hauerwas, Joel Adam January 2020 (has links)
No description available.
224

Assessment of Granulovirus, Spinosad, and Mating Disruption for Controlling <i>Cydia Pomonella</i> L. [Lepidoptera: Tortricidae] in Organic Coastal California Apple Orchards

Lukehart, Raven 01 August 2018 (has links) (PDF)
Codling moth, Cydia pomonella[Lepidoptera: Tortricidae], is a major entomological pest of apples, pears, and walnuts cross the world (Pajac et al. 2016). Female codling moths lay eggs on the apple exocarp and larvae burrow within the fruit causing economic losses to fruit growers.Organic apple orchards in San Luis Obispo, CA currently have three codling moth, Cydia pomonella,control options commercially available including granulovirus (CpVG), spinosad, and mating disruption. In field tests on apple (Malus), we compare percent fruit injury between treatments of granulovirus (2.43 oz/ha Cyd-X® organically approved, Certis USA, Columbia MD), spinosad (4.05 oz/ha Entrust® Naturalyte® organically approved WP formation, Dow AgroSciences, Indianapolis IN), and a control. We also compared mating disruption in form of codling moth Codlemone® sex pheromone (257 ties/ha (506 mg)/acre Isomate®-OFM TT organically approved Pacific Biocontrol Corporation Vancouver, WA) against a control. Delta taps and 1 mg pheromone lures were used to trap males and track the degree day (DD) model for the two orchard’s codling moth populations to determine application timing for each treatment. A preliminary DD model was used based on the University of California at Davis Agricultural Extension codling moth DD model. During 2016 trialsno detectible control was provided by spray treatments with an average fruit injury of 26% control, 23% granulovirus, 28% spinosad. During 2016 trialsno detectible control was provided by mating disruption with an average fruit injury of 16% control and 16% pheromone. During 2017 trials there was detectible control provided by the treatments to the crop by both spray treatmentsand pheromone ties. 2017 average fruit injury for spray treatments was 51% control, 20% granulovirus, and 14% spinosad. 2017 average fruit injury for mating disruption was 29% control and 6% pheromone. Data suggest underlying relationship between location specific climate factors, cultivars, codling moth populations, and treatment efficacy.
225

Surrogate Modeling for Optimizing the Wing Design of a Hawk Moth Inspired Flapping-Wing Micro Air Vehicle

Huang, Wei 27 January 2023 (has links)
No description available.
226

'n Bydrae tot die biologie en beheer van die valskodlingmot Cryptophlebia leucotreta (Meyr.) (Lepidoptera : Eucosmidae) op nawels

Schwartz, A. (Allen) 12 1900 (has links)
Thesis (PhD )--Stellenbosch University, 1981. / EKSERP: Vanwee die voortdurende probleme wat die valskodlingmot, Cryptoph lebia leucotreta (Meyr.), by die verbouing van nawels in die Oos-Transvaalse Laeveld daarstel, is 'n indringende studie van hierdie insekprobleem onderneem. Die biologie van die insek is onder sowel laboratorium as natuurlike toestande nagevors. Daar is bevind dat temperatuur 'n belangrike rol in die ontwikkeling van die insek speel. By 20 tot 30°C het temperatuurstygings die ontwikkeling van die insek laat versnel. By 35°C het die lewensduur van die volwasse motte afgeneem en is geen eiers gelê nie . Die valskodlingmot is deur middle van 'n kunsmatige metode geteel om genoegsame proefmateriaal te verkry. Verskeie verbeteringe is in die bestaande tegniek aangebring.
227

Selection and Floral Evolution in Platanthera bifolia and P. chlorantha (Orchidaceae)

Maad, Johanne January 2002 (has links)
Natural selection mediated by pollinators has influenced the evolution of floral diversity of the flowering plants (angiosperms). The scope of this thesis was to study: 1) phenotypic selection, 2) mating systems, and 3) floral shifts involved in plant speciation. Model plant species were Platanthera bifolia and P. chlorantha (Orchidaceae). These orchids are moth-pollinated, strictly co-sexual (bisexual flowers), and produce a spike that displays 10-20 white flowers. I explored the influence of characters on plant fitness by using multiple linear regressions. Pollen removal (male fitness) and fruit set (female fitness) increased with more flowers per plant in three P. bifolia populations. There was selection towards longer spurs in a dry year when average spur length was shorter than in normal-wet years. Female function was sensitive to drought, which enabled an application of the male function hypothesis of floral evolution (Bateman's principle). The results show that selection may vary between populations, years, and sex-functions. I examined inbreeding by estimating levels of geitonogamy (self-pollination between flowers of an individual) with an emasculation method in two P. bifolia populations. Geitonogamy did not vary with inflorescence size. Levels of geitonogamy was 20-40% in the smaller, but non-significant in the larger population. This may relate to lower number of possible mates and pollinator activity in the smaller population. Platanthera bifolia exhibits the ancestral character state of tongue-attachment of pollinia on the pollinator. Its close relative P. chlorantha attaches its pollinia onto the pollinator's eyes. To explore the mechanism of a floral shift, pollination efficiency and speed was compared between the two species. The results showed no differences in pollination efficiency, but P. chlorantha had faster pollen export and import. Efficiency of pollination in terms of speed may cause floral shifts, and thus speciation.
228

Maximising a mutualism : sustainable bumblebee management to improve crop pollination

Feltham, Hannah January 2015 (has links)
Over 80% of wild angiosperms are reliant upon animal pollination for fruit and seed set and bees and other insects provide a vital pollination service to around a third of the crops we produce. Habitat loss, climate change and disease spread all threaten pollinator populations, with local declines and range contractions in honeybees and bumblebees leading to concerns that crop production may suffer as a result of pollinator shortages. Whilst agriculture and wildlife are often presented as being at odds with one another, the relationship between farmers growing pollination dependent crops, and the bees and insects that service them could be mutualistic. Flowering crops planted by farmers can provide an important source of forage to wild bees, whilst in return wild bees can contribute to ensuring farmers achieve adequate yields of marketable crops. The potential of this mutualistic relationship can be maximised by farmers by adopting management practices that reduce harm to, and enhance the wellbeing of, the wild bees around their farm. A group of common pesticides (neonicotinoids) used by farmers have recently been linked to pollinator ill health. Sub-lethal effects resulting from exposure to the neonicotinoid imidacloprid have been reported in honeybees and bumblebees, with bumblebee reproductive success found to diminish as a result of exposure to field realistic doses of this agrochemical. Here, the mechanism behind the reduced queen production in bumblebee colonies is suggested, with bees exposed to imidacloprid showing reduced efficiency in foraging for pollen. Farmers dependent upon pollinating insects for crop production can opt to avoid the use of pesticides known to harm these insects, however future studies are needed to identify safer alternatives that can be use in their place. Farmers can choose to increase the number of bees at their farms by utilising domesticated honeybees and purchasing commercially reared bumblebees. The use of these pollinators can ensure a minimum number of bees in the vicinity of a crop, and facilitate the production of crops at times when wild bee numbers are low. Concerns have been raised, however, regarding the use of commercially reared bees, mostly in regard to pathogen and parasite transmission, but also in respect to the possibility of outcompeting native species. Here the frequency and severity of attacks on commercial Bombus terrestris colonies, by the wax moth, an understudied bumblebee pest, are examined. Wax moths were found to infest almost half of the bumblebee nests deployed at fruit farms, with around a third of infestations resulting in nest destruction. Farmers investing in commercial bees will want to reduce the impact of harmful pests that may result in a reduced pollination service being delivered. Wax moth infestation rates at the study farms using commercial bees were high and the potential of a ‘spill- back’ effect on wild bees was examined. No evidence was found to suggest that nests in close proximity to these farms were any more or less likely to suffer from an attack than nests situated further away. Nest size was found to be the most significant predictor of an infestation, with larger nests more prone to wax moth attacks. Whilst farmers can utilise domesticated and commercially reared bees, relying on one source of pollination is inherently risky, and the most robust service will likely be provided by a range of pollinators. As well as reducing the use of chemicals known to harm beneficial insects, farmers can improve the habitat around their farms to help encourage and sustain wild pollinator populations. Sowing flower strips has been found to increase the abundance and diversity of pollinating insects, however, studies linking the use of these strips to crop production are lacking. Here we demonstrate for the first time that sowing small flower strips, adjacent to strawberry crops serviced by both wild and managed bees, can increase the overall number of pollinators foraging on the crop. This thesis contributes to our understanding of the implications of farm management decisions on pollinator health. It provides experimentally based evidence to guide farmers in making informed decisions regarding the future of crop pollination services and highlights the need for an integrated approach to managing pollination services for sustainability.
229

Efeito do estresse hídrico na composição química de brássicas e sua influência em Plutella xylostella (L., 1758) (Lep.: Plutellidae) e Trichogramma pretiosum Riley, 1879 (Hym.: Trichogrammatidae) / Effect of the water stress in the chemical composition of brassics and their influence in Plutella xylostella (l., 1758) (lepidoptera: plutellidae) and Trichogramma pretiosum Riley, 1879 (Hym.: Trichogrammatidae)

Ramalho, Dagmara Gomes 18 October 2018 (has links)
Plutella xylostella (L., 1758) (Lepidoptera: Plutellidae), também conhecida por traça-das-crucíferas, é uma praga importante de Brassicaceae, que pode ser encontrada em todos os continentes. A relação entre P. xylostella e as brassicáceas tem sido muito estudada uma vez que essa praga provoca grandes prejuízos em praticamente todas as regiões produtoras, no Brasil e no mundo. Também tem despertado grande interesse entre os pesquisadores o fato das brassicáceas utilizarem metabólicos secundários como defesa ao ataque de insetos generalistas, sendo que para especialistas, como P. xylostella, alguns desses metabólicos são incitantes de alimentação e oviposição. Na interação inseto-planta existem questões não compreendidas e que devem ser estudas, pois são diversas condições bióticas e abióticas que interagem nestes organismos, podendo promover alterações fisiológicas e nutricionais nas plantas, no desenvolvimento dos insetos e nas interações planta x herbívoro x parasitoide/predador. Assim, este trabalho objetivou estudar a influência de estresses hídricos em variedades de brássicas e seus reflexos nas plantas, no herbívoro especialista P. xylostella e no parasitoide Trichogramma pretiosum (Riley, 1879) (Hymenoptera: Trichogrammatidae). Foram efetuadas análises da composição química em folhas e da emissão de voláteis em três variedades (couve - Brassica oleracea var. acephala; brócolis - B. oleracea var. italica e repolho - B. oleracea var. capitata), em diferentes níveis de água no solo (50%, 70% e 100% da capacidade de campo), procurando-se determinar plantas comprovadamente com estresse hídrico. Também foi estudada a influência daquelas condições hídridas em parâmetros biológicos de desenvolvimento, de reprodução e de comportamento de P. xylostella, além da influência dos estresses hídricos na atratividade/repelência de T. pretiosum, parasitoide de ovos de P. xylostella. Com as variedades desenvolvidas nas três condições hídricas foram determinados: (a) nas plantas/folhas: taxa de peroxidação lipídica (MDA), porcentagem de proteína bruta na matéria seca, fibra em detergente neutro, fibra em detergente ácido, hemicelulose, lipídeos, teor de cera, proteínas insolúveis em detergente neutro, proteínas insolúveis em detergente ácido, proteínas disponíveis, matéria mineral, carboidratos totais e a emissão de voláteis; (b) com P. xylostella: consumo foliar, período larval, viabilidade larval, período pupal, viabilidade pupal, peso de pupas, razão sexual, ovos por fêmea, viabilidade de ovos, longevidade de fêmeas, longevidade de machos e tabela de vida de fertilidade, em laboratório e casa de vegetação, além da preferência para oviposição em testes com e sem chance de escolha; e (c) com T. pretiosum: teste de olfatometria com plantas nas três condições hídricas. Os resultados obtidos permitem concluir que: o déficit hídrico provoca estresse em couve, brócolis e repolho e em maior intensidade nas plantas cultivadas com menor quantidade de água disponível no solo; quantitativamente, a composição química das plantas (couve, brócolis e repolho) é alterada em função do estresse hídrico, principalmente quanto à proteína bruta e disponível, hemicelulose, lipídeos, proteínas ligadas à fibra em detergente ácido e neutro, matéria mineral e carboidratos totais; os parâmetros de desenvolvimento de P. xylostella são alterados, tanto em laboratório como em casa de vegetação, com as lagartas alimentando-se das plantas cultivadas nas diferentes condições hídricas de solo, refletindo significativamente na capacidade reprodutiva e na sobrevivência dos insetos; o estresse hídrico altera a emissão de voláteis em plantas de couve, em brócolis e repolho; a preferência de P. xylostella para oviposição, em testes com chance e sem chance, é influenciada pelo estresse hídrico em couve, brócolis e repolho; os testes de olfatometria mostram que o estresse hídrico influencia na escolha de T. pretiosum para oviposição, mais expressivamente em plantas com maiores índices de estresse hídrico / Plutella xylostella (L., 1758) (Lepidoptera: Plutellidae), also known as cruciferous moth, is an important pest of Brassicaceae, which can be found on all continents. The relationship between P. xylostella and brassicaceae has been much studied since this pest causes great damages in practically all the producing regions, in Brazil and in the world. It has also aroused great interest among researchers that brassicaceae use secondary metabolites as a defense against the attack of generalist insects, and for specialists, such as P. xylostella, some of these metabolites are prompting feeding and oviposition. In the interaction insect-plant there are questions not understood and that must be studied, because several biotic and abiotic conditions interact in these organisms, being able to promote physiological and nutritional changes in plants, in the development of insects and in the interactions plant x herbivore x parasitoid / predator. The objective of this work was to study the influence of water stresses on brassic varieties and their reflexes on plants, the P. xylostella herbivore and the Trichogramma pretiosum (Riley, 1879) (Hymenoptera: Trichogrammatidae) parasitoid. The chemical composition of leaves and the volatile emission were evaluated in three different varieties (kale - Brassica oleracea var. acephala; broccoli - B. oleracea var. italica and cabbage - B. oleracea var. capitata) in different soil water levels (50%, 70% and 100% of the field capacity), aiming to determine plants with water stress. The influence of these water conditions on biological development, reproduction and behavioral of P. xylostella, as well as the influence of water stress on the attractiveness / repellency of T. pretiosum parasitoid on P. xylostella eggs. The three varieties grown in the three water conditions and were determined: (a) in the plants / leaves: lipid peroxidation rate (MDA), percentage of crude protein in dry matter, neutral detergent fiber, acid detergent fiber, hemicellulose, lipids, wax, neutral detergent insoluble proteins, acid detergent insoluble proteins, available proteins, mineral matter, total carbohydrates and the emission of volatiles; (b) with P. xylostella: leaf consumption, larval period, larval viability, pupal period, pupal viability, pupal weight, sex ratio, eggs per female, egg viability, female longevity, male longevity and life table of fertility, laboratory and greenhouse, in addition to the preference for oviposition in tests with and without a choice; and (c) with T. pretiosum: tests of olfactometry with plants in the three water conditions. The results obtained allow us to conclude that: the water deficit causes stress in kale, broccoli and cabbage and in higher intensity in the plants cultivated with less amount of water available in the soil; quantitatively, the chemical composition of the plants (kale, broccoli and cabbage) is altered as a function of water stress, mainly as regards crude and available protein, hemicellulose, lipids, acid and neutral detergent fiber binding proteins, mineral matter and total carbohydrates; the development parameters of P. xylostella are altered, both in the laboratory and in the greenhouse, with caterpillars feeding on plants grown under different soil water conditions, significantly reflecting the reproductive capacity and survival of the insects; water stress changes the emission of volatiles in kale, broccoli and cabbage plants; the preference of P. xylostella for oviposition, in tests with chance and without chance, is influenced by water stress in kale, broccoli and cabbage; olfactometry tests show that water stress influences the choice of T. pretiosum for oviposition, more expressively in plants with higher rates of water stress
230

Efeitos da ingestão de carboidratos com reguladores de crescimento de insetos na reprodução de Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae) / Effects of the ingestion of carbohydrates with insect growth regulators on the reproduction of Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae)

Jordão, Alexandre Luis 02 April 2009 (has links)
O presente trabalho foi subdividido em quatro capítulos com os seguintes objetivos: (i) apresentar revisão bibliográfica abordando as principais referências presentes na literatura sobre a cultura da batata, Solanum tuberosum L. (Solanaceae), os aspectos bioecológicos da traça-da- -batatinha, Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae), os hormônios no desenvolvimento dos lepidópteros e a atuação de alguns reguladores de crescimento de insetos (RCIs); (ii) avaliar a ingestão dos carboidratos por adultos de P. operculella e sua influência na reprodução da espécie; (iii) testar parâmetros reprodutivos devido à ingestão de alguns ingredientes ativos presentes em RCIs; (iv) avaliar a ingestão de carboidratos aplicados sobre plantas de batata de maneira a ser possível a aplicação de RCIs como método de redução populacional da praga. Inicialmente, para comprovação da ingestão dos carboidratos, foi utilizada a técnica de marcadores coloridos, em que se ofereceu, por capilaridade via rolete dental, solução de mel a 10% contendo corante líquido artificial de coloração azul anis. Os insetos foram confinados em um recipiente cilíndrico construído com tubo de PVC rígido. Após três dias de oferecimento da alimentação, analisou-se a presença do corante no sistema digestivo dos insetos. Para verificação da ingestão de carboidrato em condições mais próximas ao ambiente das culturas agrícolas, foi realizada nova avaliação em recipientes com diferentes dimensões: 0,0018; 0,054 e 9,6 m3. Posteriormente, simulando um borrifamento na cultura, foi realizada uma terceira avaliação no ambiente de 9,6 m3, na qual a solução de mel foi oferecida aos insetos em gotas grandes no limbo foliar de plantas de batata. Para análise da influência dos carboidratos na reprodução da espécie, foram verificados os seguintes parâmetros reprodutivos: ritmo de postura, fecundidade, viabilidade dos ovos e índice de ovigenia. Para análise dos efeitos dos RCIs, foram utilizados quatro compostos com diferentes ingredientes ativos: azadiractina, lufenurom, metoxifenozida e piriproxifem. Estes compostos foram oferecidos aos insetos em solução de mel a 10%, nas concentrações de 5, 10 e 20 ppm. Durante 10 dias após o acasalamento, foram analisados os parâmetros reprodutivos. O corante colorido mostrou-se adequado para os estudos visuais do sistema digestivo de P. operculella. A ingestão dos carboidratos pelos insetos ocorreu somente quando estes foram confinados em ambientes menores, 0,0018 e 0,054 m3. No ambiente maior, de 9,6 m3, a ingestão ocorreu somente quando a solução foi oferecida via gotas em plantas de batata. Quanto aos efeitos dos RCIs, verificou-se diminuição significativa na fecundidade das fêmeas de P. operculella que ingeriram solução de mel contendo azadiractina e lufenurom à concentração de 5 ppm e piriproxifem à concentração de 20 ppm. Quanto aos parâmetros viabilidade dos ovos e período embrionário não foram verificadas diferenças significativas entre os tratamentos. Este fato sugere que a fertilidade não foi alterada, demonstrando que os RCIs não afetam os machos. A comprovação da ingestão dos carboidratos oferecido via gotas no limbo foliar de plantas de batata e os resultados obtidos na redução da fecundidade de P. operculella indicaram que esta técnica pode ser utilizada em programas de manejo integrado da traça-da-batatinha. / The present work has been subdivided into four chapters, with the following objectives: (i) to present a bibliographic review of the main aspects related to the potato crop, Solanum tuberosum L. (Solanaceae), the bioecological aspects of potato tuber moth, Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae), the hormones related to lepidopterans development and the role of some insect growth regulators (IGRs); (ii) to evaluate the carbohydrate intake by P. operculella adults and its influence on the species reproduction; (iii) to test the effects of active ingredients of IGRs on reproductive parameters; (iv) to evaluate the ingestion of carbohydrates applied on potato plants, in order to allow IGRs application as a population reduction strategy for this pest. Initially, confirmation of carbohydrate consumption was by a means colored marker technique, which offers a 10% honey solution containing an artificial liquid food dye, blue anise, by capillarity via a dental roll wick. The insects were caged in a cylindrical container made of a rigid PVC tube. After three days of food offering, dye presence was analyzed within the insects digestive system. For confirmation of carbohydrate intake under simulated field conditions, an additional evaluation was conducted in containers with different sizes: 0.0018, 0.054 and 9.6 m3. Later, a third evaluation was carried out in the 9.6 m3 container, in which the honey solution was offered to insects as big drops applied on the leaf blade of potato plants, simulating a spray application. To analyze carbohydrate influence on species reproduction, the following reproductive parameters were assessed: oviposition rate, fertility, egg viability and ovigeny index. Four compounds with different active principles were utilized to analyze IGR effects: azadirachtin, lufenuron, methoxyfenozide and pyriproxyfen. These compounds were offered to the insects in a 10% honey solution at concentrations of 5, 10 and 20 ppm. During 10 days after mating the reproductive parameters were evaluated. The colored dye method proved to be efficient for visual studies of P. operculellas digestive system. Carbohydrate ingestion by the insects occurred only when they were caged in small environments, 0.0018 and 0.054 m3. In larger ones 9.6 m3, feeding occurred when the solution was offered by dripping over potato plants. Results showed a significant reduction of P. operculella fertility among females that ingested the honey solution containing azadirachtin and lufenuron, at 5 and 20 ppm, respectively. Regarding egg viability and embrionary period, no significant differences were found between the treatments. This fact suggests that fertility was not affected, thus demonstrating that IGRs did not affect males. Confirmation of carbohydrate ingestion offered by dripping over potato leaf blades and the results of fertility reduction in P. operculella, indicated that this technique may be utilized in integrated management programs against the potato tuber moth.

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