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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.
41

Ovarian Regulation of Honey Bee (Apis mellifera) Foraging Division of Labor

January 2011 (has links)
abstract: There is increasing evidence that ovarian status influcences behavioral phenotype in workers of the honey bee Apis mellifera. Honey bee workers demonstrate a complex division of labor. Young workers perform in-hive tasks (e.g. brood care), while older bees perform outside tasks (e.g. foraging for food). This age correlated division of labor is known as temporal polyethism. Foragers demonstrate further division of labor with some bees biasing collection towards protein (pollen) and others towards carbohydrates (nectar). The Reproductive Ground-plan Hypothesis proposes that the ovary plays a regulatory role in foraging division of labor. European honey bee workers that have been selectively bred to store larger amounts of pollen (High strain) also have a higher number of ovarioles per ovary than workers from strains bred to store less pollen (Low strain). High strain bees also initiate foraging earlier than Low strain bees. The relationship between ovariole number and foraging behavior is also observed in wild-type Apis mellifera and Apis cerana: pollen-biased foragers have more ovarioles than nectar-biased foragers. In my first study, I investigated the pre-foraging behavioral patterns of the High and Low strain bees. I found that High strain bees progress through the temporal polyethism at a faster rate than Low strain bees. To ensure that the observed relationship between the ovary and foraging bias is not due to associated separate genes for ovary size and foraging behavior, I investigated foraging behavior of African-European backcross bees. The backcross breeding program was designed to break potential gene associations. The results from this study demonstrated the relationship between the ovary and foraging behavior, supporting the proposed causal linkage between reproductive development and behavioral phenotype. The final study was designed to elucidate a regulatory mechanism that links ovariole number with sucrose sensitivity, and loading decisions. I measured ovariole number, sucrose sensitivity and sucrose solution load size using a rate-controlled sucrose delivery system. I found an interaction effect between ovariole number and sucrose sensitivity for sucrose solution load size. This suggests that the ovary impacts carbohydrate collection through modulation of sucrose sensitivity. Because nectar and pollen collection are not independent, this would also impact protein collection. / Dissertation/Thesis / Ph.D. Biology 2011
42

O papel de Apis Mellifera l. como polinizador da mamoneira (Ricinus Communis L.): avaliação da eficiência de polinização das abelhas e incremento de produtividade da cultura / The role of Apis Mellifera L. how polinizador of mamoneira (Ricinus Communis L.): assessment of efficiency of bee polinização and enhancement of productivity of culture

Rizzardo, Rômulo Augusto Guedes January 2007 (has links)
RIZZARDO, Rômulo Augusto Guedes. O papel de Apis Mellifera l. como polinizador da mamoneira (Ricinus Communis L.): avaliação da eficiência de polinização das abelhas e incremento de produtividade da cultura. 2007. 78 f. : Dissertação (Mestrado) - Universidade Federal do Ceará, Centro de Ciências, Departamento de Zootecnia, Programa de Pós-Graduação em Zootecnia. Fortaleza-CE, 2007. / Submitted by Eric Santiago (erichhcl@gmail.com) on 2016-08-10T14:25:57Z No. of bitstreams: 1 2007_dis_ragrizzardo.pdf: 647782 bytes, checksum: 07ca7c3b76ed7e63c534080876f2f361 (MD5) / Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-08-10T15:17:03Z (GMT) No. of bitstreams: 1 2007_dis_ragrizzardo.pdf: 647782 bytes, checksum: 07ca7c3b76ed7e63c534080876f2f361 (MD5) / Made available in DSpace on 2016-08-10T15:17:03Z (GMT). No. of bitstreams: 1 2007_dis_ragrizzardo.pdf: 647782 bytes, checksum: 07ca7c3b76ed7e63c534080876f2f361 (MD5) Previous issue date: 2007 / The research was carried out in the Núcleo de Produção Comunitária Santa Clara, idealized and administered by the Brasil Ecodiesel Indústria e Comércio de Biocombustíveis e óleos vegetais S. A., county of Canto do Buriti, state of Piauí, Brazil, and at the Universidade Federal do Ceará, located in Fortaleza, state of Ceará. Data were collected from April 2006 to January 2007 investigating castor bean (Ricinus communis L.) pollination, the role of biotic pollinating agents and the use of the honey bee Apis mellifera in its pollination. The study aimed to contribute in mitigating yield productivity losses in this crop. The following parameters were evaluated: floral biology, castor bean pollination requirements, A.mellifera pollination efficiency, foraging behavior of A.mellifera and Scaptotrigona bipunctata in castor bean inflorescences, and physiological evaluation of fruits and seeds produced. Results showed that both bee species harvested pollen and nectar throughout the day, but S. bipunctata prefers pollen much more than nectar. The castor bean plant accepts cross pollination, but it sets significantly (p<0.05) less fruits than self-pollination. The wind appeared as the main pollen vector in the plantation. Areas where honey bee colonies were introduced produced marginally (p = 0.08) more fruits than areas where no colony was made available. Similarly, they also led to significantly (p<0.05) more fruits per raceme (22.39) heavier seeds (0,54g) greater oil percentage (54.48%) and greater gross energy (9006.81kcal/kg) than those produced in areas without introduction of honey bee colonies (15.84, 0.47g, 49.94% e 8843.29kcal/kg, respectively), Physiological evaluation of seeds found no significant differences among treatments and produced an average 84% germination. It is concluded that the wind is the major pollinator of castor bean, and this species can be pollinated and set fruits both by means of cross and self-pollination, though showing better results under autogamy. The introduction of A. mellifera colonies in castor bean plantations contributes to increase crop productivity significantly, both increasing the number of fruits set per raceme and their oil content, probably because when collecting pollen honey bees increase the amount of self-pollen floating in the air around the panicles, favoring greater proportion of self-pollination. / A pesquisa foi realizada no Núcleo de Produção Comunitária Santa Clara, idealizado e administrado pela Brasil Ecodiesel Indústria e Comércio de Biocombustíveis e óleos vegetais S. A., localizado no município de Canto do Buriti, estado do Piau, e na Universidade Federal do Ceará, localizada em Fortaleza, no estado do Ceará. A coleta de dados ocorreu durante o período de Abril de 2006 a Janeiro de 2007 com o objetivo de investigar a polinização da mamoneira (Ricinus communis L.), o papel de agentes polinizadores bióticos e a utilização de abelhas Apis mellifera na sua polinização, visando contribuir para minimizar as perdas de produtividade desta cultura. Foram avaliados a biologia floral e requerimento de polinização da mamoneira; eficiência da polinização por Apis mellifera e comportamento de pastejo de Apis mellifera e Scaptotrigona bipunctata H.(canudo) em inflorescência de mamoneira, bem como os frutos e sementes produzidas na cultura. Os resultados mostraram que as abelhas coletam pólen e néctar durante todo o dia, tendo a abelha canudo, preferência pelo pólen. A mamoneira aceita polinização cruzada, porém vingando significativamente (p<0,05) menos que a autopolinização. O vento mostrouse o principal vetor de pólen na plantação. Áreas com introdução de abelhas melíferas produziram marginalmente (p = 0,08) mais frutos que áreas sem a introdução de abelhas. De forma semelhante, também levaram a significativa (p<0,05) produção de racemos com mais frutos (22,39) e sementes mais pesadas (0,54g) com maior percentual de óleo (54,48%) e maior energia bruta (9006,81kcal/kg) do que o obtido em áreas sem abelhas (15,84, 0,47g, 49,94% e 8843,29kcal/kg, respectivamente). A avaliação fisiológica das sementes não encontrou diferenças entre os dois tratamentos, ambos apresentaram média de 84% de germinação. Pode-se concluir que o principal agente polinizador da mamoneira é o vento e que a espécie pode ser polinizada, vingando seus frutos tanto por meio de autopolinização quanto polinização cruzada, embora apresente melhores resultados com autogamia. A introdução de colônias de Apis mellifera em cultivos de mamona contribui para incremento significativo de produtividade da cultura, tanto ao aumentar o número de frutos por cacho quanto o rendimento de óleo dos mesmos, provavelmente porque ao coletar pólen as abelhas melíferas aumentam a quantidade de autopólen em suspensão no ar nas proximidades da panícula, favorecendo uma maior percentagem de autopolinização. Palavras-chave: polinização da mamoneira, rendimento de óleo, anemofilia, comportamento de pastejo, biodiesel.
43

Dieta e compotamento de forrageio de duas esp?cies de Tropidurus (Squamata,Tropiduridae) em uma ?rea de Caatinga do Nordeste do Brasil

Kolodiuk, Miguel Fernandes 28 August 2008 (has links)
Made available in DSpace on 2014-12-17T15:36:53Z (GMT). No. of bitstreams: 1 MiguelFK .pdf: 395494 bytes, checksum: 368fd1f924248774823f6b2e683fe502 (MD5) Previous issue date: 2008-08-28 / Tropidurus semitaeniatus and Tropidurus hispidus are lizard species that are widely distributed in Brazil. The former is endemic to the Caatingas, where they live in syntopy with the latter, which is distributed in other ecosystems and biomes. In this work, diet was evaluated including seasonal variations as well as foraging behavior, to determine the importance of these factors in the structure of these populations and the coexistence of these species in syntopy. No significant difference was found in diet composition between the two species, although T. hispidus feed on larger preys than do T. semitaeniatus; this fact, along with the different foraging behavior in the rainy season, are ecological factors that contribute to the syntopic coexistence of these species in the Caatinga area studied / Tropidurus semitaeniatus e Tropidurus hispidus s?o esp?cies de lagartos que t?m ampla distribui??o no Brasil, sendo que a primeira ? reconhecida como end?mica das Caatingas, onde vive em sintopia com a segunda, que se distribui em outros ecossistemas e biomas. Neste trabalho, avaliou-se a dieta incluindo varia??es sazonais e o comportamento de forrageio, para averiguar a import?ncia de tais fatores na estrutura dessas popula??es e coexist?ncia dessas esp?cies em sintopia. N?o se constatou diferen?a significativa na composi??o da dieta das duas esp?cies, embora T. hispidus se alimente de presas maiores do que T. semitaeniatus; este fato, aliado ? diferen?a no comportamento de forrageio na esta??o chuvosa, s?o fatores ecol?gicos que contribuem para a coexist?ncia sint?pica dessas esp?cies na ?rea de Caatinga estudada
44

Estudo experimental, modelagem e implementação do comportamento de colônias de formigas em um ambiente dinâmico / Experimental study, modeling and implementation of ant colony behavior in a dynamic environment

Karla Vittori 27 June 2005 (has links)
O comportamento de insetos sociais, em especial de formigas, tem sido muito estudado nos últimos tempos, devido à capacidade destes insetos realizarem tarefas complexas a partir de interações entre indivíduos simples. Ao se moverem sobre um ambiente na busca de alimento, as formigas depositam no solo uma substância química, denominada feromônio, que atrai as formigas que se encontram no ninho e as guia em direção ao alimento encontrado. O processo de construção e seguimento destas trilhas permite que as formigas descubram os menores caminhos e as melhores fontes de alimento no ambiente. Com o objetivo de estudar as características das formigas que contribuem para a sua adaptação a diferentes condições do meio, diversos experimentos vêm sendo realizados com estes insetos. Dentro deste contexto, esta tese apresenta experimentos inéditos realizados com formigas em laboratório, sobre uma rede artificial de túneis, onde diversos caminhos interconectados conduzem a uma fonte de alimento. As decisões das formigas foram analisadas nos níveis individual e coletivo, sob mudanças no meio, compreendendo o bloqueio/desbloqueio de ramos. A medição de diversas características individuais das formigas permitiu desenvolver dois modelos matemáticos sobre o seu comportamento, que foram aplicados à situação em que não se alterou a condição do ambiente com relação ao acesso aos ramos (estática), como também a mudanças no meio (dinâmica). A análise realizada do comportamento coletivo foi utilizada na comparação dos resultados obtidos pelas simulações dos modelos. De forma geral, o segundo modelo proposto foi mais eficiente que o primeiro na situação estática, porém ele ainda necessita de ajustes nas demais situações. O bom desempenho do segundo modelo proposto levou a aplicação de sua principal característica, a função de escolha que considera a concentração de feromônio sobre os ramos do meio e a capacidade de orientação das formigas, a um problema de otimização combinatorial, o roteamento em redes de telecomunicações. O algoritmo de roteamento proposto foi avaliado sob variações no nível de tráfego e topologia da rede, e seu desempenho foi comparado ao de dois algoritmos usados por concessionárias de telecomunicações, considerando diversas medidas de desempenho. O algoritmo desenvolvido obteve resultados encorajadores, sugerindo a aplicabilidade da estrutura do modelo proposto a outros problemas complexos de otimização. / The behavior of social insects, particularly of ants, has been intensively studied in the last years, due to their capacity to perform complex tasks through interactions among simple individuals. When moving in the environment searching for food, ants deposit on the ground a chemical substance, called pheromone, to attract ants in the nest and guide them towards the source of food that was found. The process of laying/following the pheromone trails allows ants to find the shortest paths and best sources of food of the environment. With the aim to study the characteristics of the ants that contribute to their adaptation to different environment conditions, several experiments with ants have been performed and reported in this research. In this context, this thesis presents novel experiments with ants in the laboratory, in an artificial network of tunnels, where several interconnected paths lead the insects from the nest to the food source. Ants\' decision were analyzed according to the individual and collective levels, under changes in the environment, comprising the blockage/release of branches. The measure of several individual characteristics of ants allowed the development of two mathematical models of their behavior, which were applied to the non-changing (static) environment access to all branches and to changing (dynamic) access. The analysis of the collective behavior of ants in the experiments was used to compare the results derived from the simulations of the models. In general, the second proposed model was more accurate than the first one in simulating ants behavior for the static situation, however, it needs some improvements for the other situations. The satisfactory behavior of the second model led to apply its main feature, the choice taking into consideration the pheromone concentration over the branches and the ants ability to orient themselves, to solve an optimization problem, the routing in telecommunications networks. The proposed routing algorithm was evaluated under variations on the traffic level and topology of the network, and its performance was compared with two routing algorithms used by telecommunications companies, considering several performance measures. The developed algorithm produced encouraging results, suggesting the possibility to apply the framework of the proposed model to other optimization problems.
45

Uso da abelha canudo (Scaptotrigona sp. nov.) na polinizaÃÃo do meloeiro (Cucumis melo L.) em ambiente protegido / Use of straw bee (Scaptotrigona sp. nov.) At the pollination of melon (Cucumis melo L.) in greenhouse

AntÃnio Diego de Melo Bezerra 07 March 2014 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / As abelhas sÃo os principais agentes de polinizaÃÃo em culturas agrÃcolas. No caso do melÃo a falta desses agentes pode resultar uma queda na produÃÃo superior a 90%. Em cultivos protegidos a introduÃÃo de abelhas vem substituindo a mÃo de obra utilizada na polinizaÃÃo manual. O objetivo desse estudo foi investigar a viabilidade da utilizaÃÃo da abelha canudo (Scaptotrigona sp. nov.) na polinizaÃÃo do melÃo var. Natal, em ambiente protegido. Para tanto, a biologia floral do meloeiro, os requerimentos de polinizaÃÃo da cultura, o comportamento, forrageio e a eficiÃncia das abelhas Scaptotrigona sp. nov. na polinizaÃÃo no ambiente protegido. O experimento foi conduzido em casa de vegetaÃÃo localizada na Embrapa AgroindÃstria Tropical, no municÃpio de Fortaleza - CE. A variedade estudada à andromonoica, com antese das flores entre 6h00 e 6h30 e fechamento por volta 20h. Durante o perÃodo de floraÃÃo do meloeiro, as flores masculinas abrem primeiro e por volta do sÃtimo dia inicia a floraÃÃo da forma hermafrodita. ApÃs esse perÃodo ambas as formas florais se mantÃm constantemente sobrepostas atà o final do perÃodo de floraÃÃo, onde hà uma reduÃÃo das flores masculinas e na sequencia das femininas. A morfometria mostrou que as flores hermafroditas (fh) sÃo significativamente maiores no seu diÃmetro do que as flores masculinas (fm) (fh = 44,17  5,77; fm= 39,29  2,38 , p < 0,001). TambÃm foi observado que as flores hermafroditas produziram maior volume mÃdio de nÃctar (5,7 &#956;L  2,72 &#956;L) do que as flores masculinas (1,85 &#956;L  0,47 &#956;L) (p < 0,05). Quanto ao requerimento de polinizaÃÃo, as flores do meloeiro var. Natal apresentaram maiores taxas de vingamento de frutos por meio da polinizaÃÃo cruzada, diferindo significativamente do tratamento com polinizaÃÃo restrita (p < 0,05). Com relaÃÃo à avaliaÃÃo de Scaptotrigona sp. nov. no cultivo protegido, as operÃrias de foram capazes de visitar em poucas horas as flores da cultura no primeiro dia da abertura da colÃnia, mas as visitas aumentaram de forma efetiva a partir do quarto dia. Foi observado que as operÃrias buscaram tanto o pÃlen quanto o nÃctar nas duas formas florais e o nÃmero mÃdio de operÃrias que saiam para as atividades de forrageamento esteve correlacionado positivamente com o volume de nÃctar disponibilizado pelas flores hermafroditas (p < 0,05). Nesse estudo foi descrito pela primeira vez o comportamento de forrageio de Scaptotrigona sp. nov em cultivo protegido, mostrando a sua alta adaptabilidade e eficiente na polinizaÃÃo das flores do meloeiro var. Natal. AlÃm disso, o vingamento dos frutos por meio da polinizaÃÃo feita por essa abelha nÃo diferiu do tratamento com polinizaÃÃo manual cruzada. Portanto, recomendamos o uso de Scaptotrigona sp. nov. em cultivo protegido para a polinizaÃÃo do meloeiro, diminuindo assim os custos de polinizaÃÃo manual nessa cultura. / Bees are the main pollinators in agricultural crops. In the case of melon lack of these agents may result in a decrease in production over 90%. In crops protected the introduction of bees is replacing the manpower used in manual pollination. The aim of this study was to investigate the feasibility of using the straw bee (Scaptotrigona sp. new) At the pollination of melon var. Natal in a protected environment. Therefore, the melon floral biology, applications pollination of culture, behavior, foraging and efficiency of bees Scaptotrigona sp. new pollination in the greenhouse. The experiment was conducted in a greenhouse located in postharvest, in Fortaleza - CE. The variety is studied andromonoecious with anthesis of flowers between 6:00 am and 6:30 am and closing at around 20:00 h. During the melon flowering period, the male flower open first and by the seventh day starts flowering hermaphrodite form. After this period both floral shapes remains constantly overlapped by the end of the flowering period, where there is a reduction of the male flowers and the sequence of the female. Morphometry showed that the hermaphrodite flowers (hf) are significantly larger in diameter than the male flowers (mf) (hf = 44.17  5.77, 39.29  mf = 2.38, p <0.001). It was also observed that the hermaphrodite flowers produced more nectar volume (5.7  2.72 uL) than the male flowers (1.85  0.47 uL) (p <0.05). As for the pollination of application, the melon flowers var. Natal had higher fruit set rates through cross-pollination, significantly different from the treatment with restricted pollination (p <0.05). As to the evaluation of Scaptotrigona sp. new in greenhouse of the workers were able to visit in a few hours the culture of flowers in the opening day of the colony, but the visits increased effectively from the fourth day. It was observed that the workers sought both the pollen and the nectar in two floral forms and the average number of workers leaving for foraging activity was positively correlated with the amount of nectar available by hermaphrodite flowers (p <0.05). In this study was first described the foraging behavior of Scaptotrigona sp. new protected cultivation, showing its high adaptability and efficient in flower pollination of melon var. Christmas. In addition, the ripening of fruits by means of pollination bees by this treatment did not differ from manual cross pollination. Therefore, we recommend the use of Scaptotrigona sp. Newin protected cultivation for pollination of melon; thereby reducing the manual pollination costs that culture.
46

Abelhas visitantes das flores do urucuzeiro (Bixa orellana L.) e suas eficiÃncias de polinizaÃÃo / Visitors of the bees flowers(Bixa orellana L.) and pollination efficiency

Francisca Ligia Aurelio Mesquita 26 February 2008 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / A pesquisa de campo foi conduzida na Fazenda Kiara Coeli localizada no municÃpio de Caucaia, estado do CearÃ. A coleta dos dados ocorreu de marÃo a agosto de 2007. Em um plantio de 6 ha constituÃdo por urucuzeiros hÃbridos. O trabalho objetivou conhecer os requerimentos de polinizaÃÃo do urucuzeiro (Bixa orellana L.), identificar seus visitantes florais e avaliar a eficiÃncia polinizadora dos agentes biÃticos mais freqÃentes nas flores da cultura. Os requerimentos de polinizaÃÃo foram avaliados por estudos de biologia floral, receptividade do estigma e tratamentos de polinizaÃÃo livre, polinizaÃÃo manual cruzada, autopolinizaÃÃo manual, polinizaÃÃo restrita com filà e polinizaÃÃo restrita com papel; os visitantes florais foram capturados para identificaÃÃo e suas freqÃÃncias e comportamento de pastejo observados usando transetos percorridos regularmente no cultivo. A eficiÃncia de polinizaÃÃo dos visitantes florais mais freqÃentes Ãs flores foi feita por meio de visitas Ãnicas e avaliaÃÃo do tamanho, peso e nÃmero de sementes dos frutos produzidos. Os resultados mostraram que as flores do urucuzeiro duram apenas um dia e possuem anteras poricidas que necessitam serem vibradas para liberar pÃlen, apresentam receptividade apenas no perÃodo da manhÃ, especialmente entre 9:30 e 10:30 h, e produzem significativamente (p<0,05) mais frutos sob polinizaÃÃo cruzada do que autopolinizaÃÃo. As flores foram visitadas por insetos das Ordens: Diptera, Coleoptera e Hymenoptera, principalmente 13 espÃcies de abelhas das famÃlias Antophoridae, Apidae, Halictidae e Andrenidae, a saber: Xylocopa frontalis, Xylocopa grisensces, Xylocopa muscaria, Exomalopsis analis, Apis mellifera, Melipona subnitida, Partamona sp., Trigona spinipes, Eulaema nigrita, Euglossa sp, Megalopta sp., Augochloropsis sp. e Oxaea sp. As abelhas coletaram exclusivamente pÃlen, principalmente no perÃodo da manhà e variaram em freqÃÃncia, comportamento de pastejo e eficiÃncia em vingar frutos com apenas uma visita à flor (p<0,05). Concluiu-se que a polinizaÃÃo do urucuzeiro à predominantemente xenÃgama e dependente de agentes biÃticos, principalmente abelhas; o comportamento de pastejo do visitante floral à de fundamental importÃncia para determinar sua eficiÃncia como polinizador do urucuzeiro, e as abelhas Xylocopa frontalis, Augochloropis sp. e Eulaema nigrita, por ordem de importÃncia, foram os polinizadores mais efetivos na Ãrea estudada, devendo suas presenÃas serem incrementadas no plantio / The research was carried out in the farm Kiara Coeli situated in the county of Caucaia, state of CearÃ, Brazil. Data gathering took place from March to August 2007. In a 6ha crop made up of hybrids annatto plants. The work aimed to know the pollination requirements of annatto (Bixa orellana L.), to identify its floral visitors and the pollination efficiency of the most frequent floral visitors. Pollination requirements were evaluated by means of studies in floral biology, stigma receptivity and treatments of open pollination, hand cross pollination, self-pollination, muslin bag restricted pollination and paper bag restricted pollination; floral visitors were captured for identification and their frequency and foraging behavior were observed using transects which were walked in a regular basis throughout the day. Pollination efficiency of the most frequent floral visitors was assessed allowing one-floral visit only, and measurements of size, weight and number of seeds produced per fruit. Results showed that the annatto flowers last only one day and bear poricidal anthers that need to be vibrated to release pollen, are receptive only in the morning shift, especially between 9:30 and 10:30 h, and produce significantly (p<0,05)more fruits under cross pollination than self-pollination. Flowers were visited by insects of the Orders Diptera, Coleoptera and Hymenoptera, mainly 13 bee species belonging to the families Antophoridae, Apidae, Halictidae and Andrenidae, namely: Xylocopa frontalis, Xylocopa grisensces, Xylocopa muscaria, Exomalopsis analis, Apis mellifera, Melipona subnitida, Partamona sp., Trigona spinipes, Eulaema nigrita, Euglossa sp, Megalopta sp.,Augochloropsis sp. and Oxaea sp. Bees collected exclusively pollen, mainly early in the morning and varied (p<0,05) in frequency to flowers, foraging behavior and pollinating efficiency with only one floral visit. It was concluded that pollination in annatto is mainly xenogamous and dependent upon biotic agents, especially bees; the floral visitorâs foraging behavior is of paramount importance to determine its pollination efficiency of annatto flowers, and the bee species Xylocopa frontalis, Augochloropis sp. and Eulaema nigrita, by order of importance, were the most effective pollinators in the studied area, and their presence should be improved in the site
47

Manejo de Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera: Noctuidae) em milho, Zea mays L.: bases para avaliação populacional e controle biológico utilizando o parasitóide de ovos Trichogramma atopovirilia Oatman & Platner, 1983 (Hymenoptera:Trichogrammatidae) / Management of Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera: Noctuidae) on corn, Zea mays L.: basis for populational evaluation and biological control using the egg parasitoid Trichogramma atopovirilia Oatman & Platner, 1983 (Hymenoptera: Trichogrammatidae).

Alexandre Moraes Cardoso 26 April 2004 (has links)
A presente pesquisa teve como objetivos aprimorar a amostragem de Spodoptera frugiperda através do uso de armadilhas com feromônio sexual, verificar a capacidade de dispersão de Trichogramma atopovirilia como agente de controle biológico desta praga bem como avaliar a atratividade de Amaranthus sp. às fêmeas de T. atopovirilia. Para aprimorar a amostragem de S. frugiperda, os estudos foram conduzidos em dois campos comerciais de produção de milho, sendo um composto de 36,3 ha (denominado de MIP e com 30 pontos de amostragem) e outro de 10 ha (denominado de convencional e com 10 pontos de amostragem). Nestes campos foram instaladas armadilhas com feromônio sexual, distribuídas de forma aleatória e na proporção de 1 armadilha / ha. As avaliações foram realizadas duas vezes por semana durante todo o desenvolvimento das plantas, considerando-se: número de adultos machos coletados pelas armadilhas, injúria dos insetos às plantas, número de posturas e de larvas (pequenas, médias e grandes). O número de adultos coletados nas armadilhas foi correlacionado com os níveis de injúrias, número de posturas e densidade larval. O número de larvas observadas não apresentou diferença entre áreas e pontos de amostragem. A injúria dos insetos às plantas, número de posturas e de larvas pequenas não apresentaram correlação com os adultos capturados pelas armadilhas. Houve correlação significativa entre o número de larvas grandes (4o e 5o ínstares) e o número de plantas apresentando o cartucho furado ou destruído. Não houve correlação da coleta de adultos nas armadilhas com a infestação ou níveis de injúria, demonstrando que as larvas ainda precisam ser contadas para determinar o momento do seu controle. A capacidade de dispersão de T. atopovirilia foi estudada em 3 fases distintas de desenvolvimento das plantas de milho, quando estas possuíam de 4 a 6 folhas, 8 a 10 folhas e pendoamento. Em cada fase foi realizada uma infestação artificial com posturas (até 24 h) de S. frugiperda nas plantas localizadas em distâncias que variaram de 6 a 24 m do ponto de liberação do parasitóide. Logo após esta infestação, foi realizada somente uma liberação de adultos do parasitóide para cada fase da cultura e sempre no período mais fresco do dia (manhã ou entardecer). O parasitismo foi permitido durante até 48 horas quando as posturas eram recolhidas e acondicionadas em câmara climatizada até a emergência dos adultos. Os resultados indicaram que as plantas em suas diferentes fases de desenvolvimento afetaram a capacidade de dispersão dos parasitóides. As posturas localizadas nos pontos mais distantes somente foram atingidas pelos parasitóides durante a fase de desenvolvimento da cultura em que as plantas de milho estavam menores (4 a 6 folhas). Nas outras fases, os índices de parasitismo foram maiores naquelas posturas localizadas mais próximas do ponto de liberação. A atratividade de quatro espécies de Amaranthus (A. retroflexus, A. viridis, A. hybridus e A. spinosus) às fêmeas de T. atopovirilia foram avaliadas utilizando-se olfatômetro Peterson. Estas plantas foram testadas em período de desenvolvimento vegetativo e reprodutivo. Adotou-se o delineamento inteiramente casualizado com 40 repetições (considerando-se um inseto/ repetição) e cada inseto foi observado durante o tempo máximo de 600 segundos. As espécies mais atrativas foram A. viridis e A. retroflexus, nos estádios vegetativo e reprodutivo, respectivamente. Quando testadas simultaneamente, as espécies de plantas não demonstraram atratividade ao parasitóide. Estes resultados sugerem a viabilidade do uso destas plantas ou seus derivados no manejo de habitats de hospedeiros e aumento de parasitismo em programas de manejo integrado de pragas. / The objectives of this research were the improvement of cross-section Spodoptera frugiperda using pheromone traps to verify the capacity of dispersion of Trichogramma atopovirilia as an agent for biological pest control as well as evaluating the attractiveness of Amaranthus sp. to T. atopovirilia females. To improve cross-section of S. frugiperda, the studies were carried out in two commercial corn field plantations, one made up of 36,3 ha (called MIP and with 30 points of sampling) and another of 10 ha (called conventional and with 10 points of sampling). In these fields pheromone traps were randomly displaced (ratio of 1 trap/ha). The evaluations were realized twice a week during the whole plant development, considering : number of male adults collected by the traps, insect injury to plants, egg masses and larval densities (small, medium and large). The numbers of adults collected were correlated to the insect injury, egg masses and larval density. The larval occurrence did not show difference between areas and sampling points. The injury levels, egg masses and small larva densities did not show correlation to adult caught by traps. There was significant correlation between large larvae (4th and 5th instars) and the number of plants showing whorl holes and/or destroyed ones. There were no correlations observed among adults caught by traps and insect infestation or injury, so demonstrating that larvae should be counted for timing pest control. The capacity of dispersion of T. atopovirilia was studied in 3 distinct phases of corn plant development, when they had 4 to 6 leaves, 8 to 10 leaves and tassel. In each stage was applied an artificial infestation with egg masses (< 24 h) of S. frugiperda on plants located 6 to 24 m from a parasitoid release point. Right after this artificial infestation, was applied only one parasitoid adult release to each distinct corn plant phase , always early in the morning or late in the afternoon. The parasite contamination was allowed during 48 h and then the egg masses were retrieved and taken into a climatic chamber until emerging adulthood. The results showed that plants affected the parasitoid dispersal. The egg masses placed farthest from the release point were parasited only during the 4 to 6-leaf stage. In the others stages, only egg masses next to the release point were parasited. The attractiveness of four species of Amaranthus (A. retroflexus, A. viridis, A. hybridus and A. spinosus) to the females of T. atopovirilia was evaluated by a Petersons olfactometer. These plants were evaluated in both vegetative and reproductive stages. Complete randomized procedure was adopted with 40 replications (considering one insect/replication) and each insect was observed during 600 seconds. The most attractive species were A. viridis and A. retroflexus during vegetative and reproductive stage, respectively. When plants were tested simultaneously, the species did not show attractive properties to the parasitoids. These results suggest the viability of the use of these plants or its derivatives to change host habitat and parasite increase for biological control in integrated pest management.
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Abelhas eussociais (Hymenoptera, Apidae) que ocorrem em jardins urbanos em Juiz de Fora, MG: recursos florais e atividade de voo

Castro, Lívia Cabral de 20 January 2009 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-10-06T15:39:53Z No. of bitstreams: 1 liviacabraldecastro.pdf: 1753178 bytes, checksum: 70a02d35eda1c8312e39fcd90d748a40 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-10-07T12:13:48Z (GMT) No. of bitstreams: 1 liviacabraldecastro.pdf: 1753178 bytes, checksum: 70a02d35eda1c8312e39fcd90d748a40 (MD5) / Made available in DSpace on 2016-10-07T12:13:48Z (GMT). No. of bitstreams: 1 liviacabraldecastro.pdf: 1753178 bytes, checksum: 70a02d35eda1c8312e39fcd90d748a40 (MD5) Previous issue date: 2009-01-20 / O processo de urbanização modifica o ambiente, alterando os locais de nidificação e diminuindo as fontes de recursos tróficos de muitas espécies de abelhas. Este estudo teve como objetivo estimar a riqueza de abelhas eussociais, assim como as plantas visitadas por essas abelhas em um ambiente antrópico. Além disso, verificou-se a influência da temperatura, umidade, luminosidade e velocidade do vento na atividade de voo de Nannotrigona testaceicornis (Lepeletier, 1836) e Tetragonisca angustula (Latreille, 1811) nesse ambiente. A assembléia de abelhas foi amostrada mensalmente, das 9 às 16h, em três praças de Juiz de Fora, Minas Gerais, durante o período de um ano. Três amostras das espécies de plantas foram coletadas para a identificação e herborização. Para avaliar a influência dos fatores climáticos na atividade de voo realizou-se 12 observações em colônias de N. testaceicornis e 12 em T. angustula, com periodicidade mensal, durante os meses de outubro/2007 a setembro/2008. A temperatura, umidade relativa do ar, luminosidade e velocidade do vento foram registradas a cada hora nas proximidades das colônias. No total foram registradas 10.318 abelhas eussociais, pertencentes a oito espécies; 7337 referentes à subtribo Meliponina e 2981 à subtribo Apina. Aproximadamente 90% das plantas visitadas pelas abelhas foram espécies exóticas. Trigona spinipes (Fabricius, 1793) foi a única espécie presente em todas as coletas e a que utilizou o maior número de plantas. A fauna de abelhas registrada em praças de Juiz de Fora apresentou poucas espécies, sendo que a metade dessas foi considerada constante. Embora tenham sido constatadas características particulares para cada praça, como a disponibilidade de recursos florais, verificou-se que a intervenção antrópica, como a poda das plantas foi um fator que influenciou o número de indivíduos ao longo do ano. A amplitude máxima diária de atividade de voo foi de aproximadamente onze horas, entretanto esse valor variou durante os meses de observação. O maior fluxo de saídas e retornos das abelhas foi observado entre 10:00 e 13:00. A maioria das saídas, aproximadamente 60%, das operárias de ambas as espécies foi influenciada pela temperatura e luminosidade. Desta forma, os resultados encontrados no presente estudo contribuem para ampliar o conhecimento sobre a atividade dessas abelhas em ambiente antrópico. / The urbanization process modifies the environment, changing the nest foundation places and reducing the trophics resource spots. The objectives of this research were to estimate the eusoical bee’s richness and also the plants utilized by these bees in an anthropic environment. It was also checked the influence of temperature, humidity, luminosity and air speed during flight activity of Nannotrigona testaceicornis (Lepeletier, 1836) and Tetragonisca angustula (Latreille, 1811) in this environment. The bees assembly was verified, from 9am to 6pm, in three places in Juiz de Fora, during a period of one year. To evaluate the influence of the climate factors during flight activity were realized 12 observations in N. testaceicornis and 12 in T. angustula colonies, every month, during the months of October/2007 and September/2008. The temperature, air relative humidity, luminosity and air speed were registered every hour near the colony. In total were register 10.318 eusocial bees, belonging to eight different species; 7337 from the sub tribe Meliponina and 2981 from the sub tribe Apina. Approximately 90% of the plants utilized by the bees were exotic. Trigona spinipes (Fabricius, 1793) was the only species registered in all the study and the one that utilized the biggest number of plants. The bees’ fauna registered in public squares of Juiz de Fora presented few species, and half of these was considered constant. Although each square had their own characteristics, as the availability of floral resources, it was verified that the anthropic intervention, as, the pruning of the plants was a factor that influenced the number of individuals throughout the year. The biggest amplitude of flight activity was approximately eleven hours, although this value varied during the observation months. The biggest bees’ departures and returns flow was registered between 10:00am and 01:00pm. The majority of departures, about 60%, of workers of both species was influenced by temperature and luminosity. In such a way, the results found in the present study contribute to extend the knowledge of the activity of these bees in anthropical environment.
49

Genetics of foraging behavior of the predatory mite, Phytoseiulus persimilis

Konakandla, Bhanu S. January 1900 (has links)
Master of Science / Department of Entomology / David C. Margolies / Yoonseong Park / Phytoseiulus persimilis (Acari: Phytoseiidae) is a specialist predator on tetranychid mites, especially on the twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae). The foraging environment of the predatory mites consists of prey colonies distributed in patches within and among plants. Quantitative genetic studies have shown genetic variation in, and phenotypic correlations among, several foraging behaviors within populations of the predatory mite, P. persimilis. The correlations between patch location, patch residence, consumption and oviposition imply possible fitness trade-offs. We used molecular techniques to investigate genetic variation underlying the foraging behaviors. However, these genetic studies require a sufficiently large amount of DNA which was a limiting factor in our studies. Therefore, we developed a method for obtaining DNA from a single mite by using a chelex extraction followed by whole genome amplification. Whole genome amplification from a single mite provided us with a large quantity of high-quality DNA. We obtained more than a ten thousand-fold amplified DNA from a single mite using 0.01ng as template DNA. Sequence polymorphisms of P. persimilis were analyzed for nuclear DNA Inter Transcribed Spacers (ITS1 & ITS2) and for a mitochondrial 12S rRNA. The sequence comparisons among individuals identified a number of polymorphisms in the 12S sequences. The foraging gene (for) associated with rover-sitter behavioral strategies of Drosophila is known to have role in feeding behaviors of honeybee and other arthropods. We surmised that the same or a similar gene may be present in P. persimilis. Among the foraging behavior(s) exhibited by this predatory mite, we were particularly interested in resource/prey-dependent dispersal behavior. We isolated a partial sequence that is presumed to be the orthologue of the foraging (for) gene. We named the putative foraging gene as Ppfor (for Phytoseiulus persimilis foraging gene). We used a fragment of Ppfor gene as a molecular marker between populations and among individuals and, further, to help understand behavioral phenotypes.
50

Effects of plant architecture and prey distribution on the foraging efficiency and behavior of the predatory mite Phytoseiulus persimilis (Acari:phytoseiidae)

Gontijo, Lessando Moreira January 1900 (has links)
Master of Science / Department of Entomology / David C. Margolies / James R. Nechols / The study of how extrinsic factors affect the foraging efficiency and behavior of predaceous arthropods like Phytoseiulus persimilis is important to understand their various processes of acquiring prey, mates, refuges, oviposition sites, and overcoming obstacles posed by the environment. Many intrinsic and extrinsic factors affect predator foraging efficiency and behavior. One of the most influential extrinsic factors may be the host plant on which herbivorous prey are found. Recent studies suggest that plant architecture plays an important role in tritrophic interactions. In this work, I studied the effects of cucumber plant architecture and prey distribution on the foraging efficiency (prey-finding time and prey-consumption rate) and behavior (time allocated between moving, resting and feeding) of P. persimilis. Plant architecture represented differences in leaf number and size; however, all plants had the same total surface area. Plants with 6 small leaves (ca. 82.98 square cm each) were considered as complex architecture, whereas plants with only 2 large leaves (ca. 240.60 square cm each) were considered as simple. The prey distributions were: prey patch on a single basal leaf (closest leaf to the soil) and prey patch on all leaves. The foraging efficiency was assessed by measuring prey-finding time and prey-consumption rate, whereas the behavior was assessed by conducting observational studies on specific foraging activities. When placed either on the top or at the base of the plant P. persimilis encountered prey more rapidly (interval 0-30 minute) on complex and simple plants with prey patches distributed on all leaves. Differences in prey density (number of prey per leaf) had no effect on the prey-finding time of P. persimilis. The predator consumed more eggs on complex plants with prey patches distributed on all leaves. Phytoseiulus perismilis tended to find prey patches more quickly as well as consume more eggs on leaves close to its release point. Furthermore, the predator was observed to lay more eggs on leaves where it had consumed higher number of prey eggs. The dimensions of individual parts of the plant e.g., stem, petiole and leaf, affected the time allocated by P. persimilis between searching, resting and feeding. The predatory mite spent more time foraging on the stems and petioles of the simple plants whereas on complex plants it spent more time foraging on the leaves.

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