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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.
31

Análise da estrutura populacional de Aedes aegytpi (Linnaeus, 1762) em algumas regiões do Brasil

Bronzato, Aline Ribeiro. January 2015 (has links)
Orientador: Paulo Eduardo Martins Ribolla / Banca: Fernando Araújo Monteiro / Banca: Jayme Augsto de Souza Neto / Banca: Mara Anice Mured Allum / Banca: Renata Schama / Resumo: Aedes aegypti é considerado o principal vetor de arboviroses que acomentem os seres humanos. Até o momento a única medida disponível para erradicação da dengue, é o controle do vetor, Ae. aegypti. O conhecimento aprofundado sobre a estruturação genética e dinâmica populacional dessa espécie em diferentes ambientes é crucial, uma vez que populações geneticamente diferentes podem apresentar diferenças quanto à capacidade e competência vetorial. O Brasil possui regiões com diferentes características climáticas e geográficas, assim o conhecimento detalhado sobre populações de mosquitos que colonizam diferentes habitats, é pertinente. Este trabalho avaliou a estrutura populacional de mosquitos Ae. aegypti provenientes de cinco cidades do Brasil (i.e., Belo Horizonte, Botucatu, Campo Grande, Maringá e Rondonópolis) utilizando marcadores microssatélites. Ainda, empregouse esses marcadores para investigar a dinâmica de oviposição e consequente dispersão de mosquitos Ae. aegypti em Botucatu. Em macro-análises populacionais, utilizando DAPC, observamos agrupamento entre indivíduos de mesma localidade e estruturação populacional para mosquitos de Belo Horizonte. Análises de micro-estruturação populacional identificaram seis sub-populações de mosquitos Ae. aegypti entre as seis sub-regiões de Belo Horizonte, ainda foram sugeridas estruturação populacional intermediária para mosquitos das sub-regiões de Campo Grande e falta de estruturação genética entre mosquitos das subregiões de Botucatu. Com esses resultados acreditamos que estruturação genética ocorra em correlação com o tamanho da cidade - localidades maiores parecem proporcionar estruturação genética para populações de mosquitos Ae. aegypti. Análises de PCA em ovitrampas da cidade de Botucatu apontaram organização populacional de Ae. aegypti em famílias. Análises de Pedigree e coeficiente de inbreeding, indicaram que de 30 mosquitos... / Abstract: Aedes aegypti is considered the main vector of arboviruses affecting humans. Nowadays, the only feasible measure to eradicate the dengue fever depends exclusively of vector control. The deep knowledge about the structure and dynamics of Ae. aegypti population in distinct environments is critical, since genetically different populations may present differences related to vector competence and capacity. Brazil has regions with different climatic and geographic characteristics, therefore, detailed knowledge about mosquito population that colonizes different habitats is extremely important. The present study evaluated the population structure of Ae. aegypti mosquitoes in five different Brazilian cities (i.e., Belo Horizonte, Botucatu, Campo Grande, Maringá and Rondonópolis) using a microsatellite markers. Those markers were also used to evaluate the oviposition dynamic and the consequences of Ae. aegypti mosquitoes dispersion, of the city of Botucatu. Population macro-analysis, using DAPC evidenced, genetic clusters among individuals of the same locality, and population structure in mosquitoes of Belo Horizonte. Population microstructure analysis identified six sub-populations of Ae. aegypti mosquitoes among six sub-regions of Belo Horizonte. In addition, the microstructure analysis suggested intermediate population structure in the sub-regions of Campo Grande, and lack of genetic structure among mosquitoes from the sub-regions of Botucatu. Therefore, these results indicate that genetic organization occurs in correlation with city size - where large towns seem to provide genetic structure to the populations of Ae. aegypti. PCA analysis of ovitraps obtained in Botucatu indicated population organization of Ae. aegypti mosquitoes in families. Pedigree analysis and inbreeding coefficient indicated that only for out of 30 mosquitoes analyzed in the same ovitrap, keep restricted familial relationships. These results suggest that Ae. aegypti... / Doutor
32

The role of host plants and parasitoids on the abundance of spring populations of Heliothis spp. in Arizona

Rathman, Robin Jean January 1981 (has links)
No description available.
33

Response of carabid and cicindelid beetles to various types of landscape disturbances.

Jaganyi, Joan N. U. 23 December 2013 (has links)
A study of carabids and cicindelids was carried out in eastern South Africa using the same methodology as has been used in the northern hemisphere to obtain a southern hemisphere perspective. The study used the macroecology approach to compare patterns and responses of these animals to anthropogenic disturbances in visually similar habitats (forests, grasslands). Although this is essentially a local component of a larger macroecological study, it is shown that even though species and identities differ between the north and southern hemispheres, the general patterns of community response to anthropogenic disturbances are surprisingly similar. Changes in carabid assemblages were assessed across eight sites or landscape elements experiencing a range of disturbance types, both regular and irregular (such as mowing, fire, irrigation, fertilizers, pesticides, forestry). Direct comparisons were made with similar studies in the Palaearctic. Species diversity, seasonal population variations, population phenology, spatial patterns and mean body size of species assemblages relative to the landscape elements are described. As in the north, intensively disturbed biotopes were impoverished, and natural patches of moist forest acted as habitat sources for these disturbed sinks. Roadside verges were species-rich analogues of natural habitats. The mean body size of carabid assemblages in forest and grassland sites decreased with increasing intensity of disturbance. One contrary comparison with the north was that a plantation, in this case macadamia, was exceptionally rich in carabid species and individuals. Classification and ordination methods identified and characterised the eight sites to six ecological meaningful biotopes for carabids and cicindelids. This also allowed inferences as to how the various landscape disturbances in natural forests, planted pine forests, macadamia plantation, recreational park, road verge grasslands and hayfields affect carabid and cicindelid species richness and abundance. Species assemblages that responded to these anthropogenic impacts were potential indicator groups that can assist in the planning and management of forest and grassland landscapes for conservation of biodiversity. Some management recommendations for these landscapes are given. Individual species-environment relations were investigated using both univariate and multivariate analyses. The solutions to these analyses were then used to describe how species are distributed along major environmental gradients. It was shown that soil characteristics (pH, moisture, twig and/or leaf litter) determine carabid and cicindelid assemblages. Land-use and management regimes influence these patterns. The effect of altitude is masked by the presence of soil characteristics in a multivariate analysis, and more so in the presence of pH and moist soil-sand gradients with changing altitude. In the absence of soil characteristics and in univariate analysis, altitude becomes very important. Altitude has therefore an indirect effect in that it determines climate, which, in turn, determines soil and vegetation type which then determines species presence and abundance. It is concluded that the macroecological approach has great potential for teasing apart local effects from global ones, and can contribute to the conservation of biodiversity at both small and large scales. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 1998.
34

Mathematical models for the population dynamics and management of the carrot weevil, Listronotus oregonensis (LeConte) (Coleoptera:Curculionidae)

Zhao, Dingxin January 1990 (has links)
The time-varying survival rates of the carrot weevil, Listronotus oregonensis, were estimated by a new method. This method precluded the possibility of negative simulation survival rates. Analysis of carrot weevil population dynamics indicated that the egg mortality was density dependent with Anaphes sordidatus, an egg parasitoid, as a major density dependent factor. Larval mortality was less density dependent. Based on the mortality information, a simulation model for carrot weevil population dynamics was established. The simulation precision, evaluated by comparing simulated and observed egg and larval population dynamics, was satisfactory. Sensitivity analysis indicated that A. sordidatus had a large influence on carrot weevil population dynamics. The economic threshold for carrot weevil control in early carrots was 5 eggs/100 carrots at the peak population density. It ranged from 3.8 to 5.3 eggs/100 carrots in mid-season carrots depending on the selling price. A decision model showed that the best sowing date was after June 5 when risks were not considered. For risk aversion growers, sowing carrots between May 20 and May 31 was the best choice.
35

Mathematical models for a population of insects infesting stored cereal products : with reference to weevils in wheat / by Livingstone Serwadda Luboobi

Luboobi, Livingstone Serwadda January 1980 (has links)
Bibliography: leaves A19-A23 / ix, 183, 23 leaves : ill ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Applied Mathematics, 1982
36

Mathematical models for a population of insects infesting stored cereal products : with reference to weevils in wheat

Luboobi, Livingstone Serwadda. January 1980 (has links) (PDF)
Bibliography: leaves A19-A23.
37

Distribuição espacial e dinâmica populacional de Sphenophorus levis (Coleoptera: Curculionidae) em cana-de-açúcar /

Izeppi, Tiago Sabongi. January 2015 (has links)
Orientador: José Carlos Barbosa / Coorientador: Leila Luci Dinardo-Miranda / Banca: Nilza Maria Martinelli / Banca: Renata Moreira Leal / Resumo: O conhecimento da dinâmica populacional e do padrão de distribuição de insetos em ecossistemas agrícolas é importante para o desenvolvimento de estratégias de manejo mais eficazes, auxiliando em uma melhor tomada de decisão. O objetivo deste trabalho foi estudar a distribuição espacial e a dinâmica populacional de Sphenophorus levis Vaurie (Coleoptera: Curculionidae) em cana-de-açúcar. No estudo da distribuição espacial, foram realizadas amostragens em 14 áreas comerciais de cana-de-açúcar, avaliando 100 pontos de amostragem por área, através de trincheiras na linha de cana de 50 x 50 x 30 cm, para contagem de larvas, pupas e adultos de S. levis e de seus danos, representados pela porcentagem de rizomas danificados pela praga. Nas áreas 6 a 14, na ocasião da amostragem, foram distribuídas iscas para contagem dos adultos presentes fora dos rizomas. A distribuição espacial foi estudada através da análise geoestatística. Para o estudo da dinâmica populacional, foi utilizada uma área comercial de cana soca em 2° corte cultivada com a variedade SP81-3250, no município de Américo Brasilense, SP. Foram feitas amostragens mensais através da abertura de 20 trincheiras na linha de cana, de 50 x 50 x 30 cm, para contagem de formas biológicas da praga presentes no rizoma (larvas, pupas e adultos). Nas mesmas ocasiões foram distribuídas na área 20 iscas, para contagem dos adultos. As larvas, formas biológicas totais (larvas + pupas + adultos) e o dano de S. levis distribuíram-se de maneira agregada, enquanto pupas e adultos distribuíram-se aleatoriamente em campo. Os valores de alcance obtidos e os mapas de interpolação por krigagem mostraram grande variabilidade das populações do inseto e seu dano em todas as áreas estudadas. Com base no alcance médio obtido para as variáveis estudadas, sugere-se que para estimar as populações do inseto e seu dano em canaviais os pontos de amostragem devem ser... / Abstract: The knowledge of the population dynamics and insect distribution pattern in agricultural ecosystems is important for the development of more effective management strategies, assisting in better decision making. The objective of this work was to study the spatial distribution and population dynamics of Sphenophorus levis Vaurie (Coleoptera: Curculionidae) in sugarcane. In the study of spatial distribution, sampling was performed in 14 commercial areas of sugarcane, evaluating 100 sampling points per area through the trenches of 50 x 50 x 30 cm made in the line, for counting larvae, pupae, and S. levis adults and their damage, represented by the percentage of rhizomes damaged. In areas 6 to 14, at the time of sampling, baits were distributed for adult counts present outside the rhizomes. The spatial distribution was studied by geostatistical analysis. For the study of population dynamics, we used a commercial area of sugarcane in 2nd cut cultivated with SP81-3250 variety in the city of Américo Brasilense, SP. Monthly samples were taken through the opening 20 trenches in the cane row, 50 x 50 x 30 cm, for counting biological forms of pest present in the rhizome (larvae, pupae and adults). In the same occasion 20 baits were distributed in the area to count adults. The larvae, total biological forms (larvae + pupae + adults) and the damage S. levis were agregate, while pupae and adults distributed randomly in the field. The range of values obtained and the kriging interpolation maps showed large variability in insect populations and their damage in all studied areas. Based on the mid-range obtained for the variables studied, it is suggested that to estimate insect populations and their damage the sampling points should be spaced at 40 m. All the insect biological forms were found in the area during the year, however, the population peaks of adults occurred in rainy and warm time of year, in February and March, while larvae and pupae in more ... / Mestre
38

Desempenho de populações geográficas de Helicoverpa armigera (Hübner) (Lepidoptera : Noctuidae) em dietas naturais e artificial e caracterização por microssatélites /

Silva, Ivana Fernandes da, 1986. January 2017 (has links)
Orientador: Edson Luiz Lopes Baldin / Coorientador: Alexandre Specht / Banca: José Paulo Gonçalves Franco da Silva / Banca: Carlos Frederico Wilcken / Banca: Daniel Ricardo Sosa-Gomez / Banca: André Luiz Lourenção / Resumo: Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) possui ampla distribuição geográfica e é reponsável por perdas econômicas em várias culturas de importância agrícola ao redor do mundo. As lagartas apresentam grande plasticidade em termos de exigência nutricional e, devido à polifagia, se adaptam a diversos hospedeiros, com valores nutricionais variados, os quais podem afetar seu desenvolvimento biológico. Considerando a recente introdução do inseto no Brasil (2013), aliada à falta de consenso sobre a origem das populações a campo, dificuldades no estabelecimento de criações massais, bem como a necessidade de maior entendimento sobre sua interação com os hospedeiros em nosso país, este estudo teve como objetivos: disponibilizar uma dieta padronizada para criações de H. armigera em laboratório (25±2°C, 70±10% U.R. e 14h de fotofase), caracterizar molecularmente três populações, de São Paulo, Bahia e Distrito Federal, avaliar o desempenho biológico e o potencial biótico de indivíduos provenientes de diferentes populações em dieta artificial e investigar a performance de H. armigera em estruturas vegetativas e reprodutivas de algodão, milho e soja. As análises moleculares mostraram similaridade elevada entre indivíduos das três populações, indicando uma origem única para H. armigera no Brasil. O método de criação, bem como os índices nutricionais da dieta artificial oferecida se revelaram adequados para o inseto. A viabilidade média das fases larval e pré-pupal foi semelhan... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) has a wide geographical distribution and contributes to economic losses in several crops of agricultural importance around the world. The larvae present great plasticity in terms of nutritional requirement and, due to polyphagia, they adapt to several hosts with varied nutritional values which may affect their biological development. Taking into account the recent introduction of these insects in Brazil (2013), along with the lack of consensus on the origin of their populations in the field, as well as the difficulties in establishing mass creations, and the need for greater understanding of their interaction with the hosts in our country, this study had as its objectives: to provide a standardized diet for laboratory H. armigera (25±2°C, 70±10% R.H., and 14h of phototophase); to molecularly characterize three populations from São Paulo (SP), Bahia (BA), and Distrito Federal (DF); to evaluate the biological performance and biotic potential of individuals from different populations on artificial diet; and to investigate the performance of H. armigera in vegetative and reproductive structures of cotton, corn and soybean. The molecular analyzes showed a high similarity between individuals of the three populations, which indicates a unique origin for H. armigera in Brazil. The breeding method, as well as the nutritional indexes of the artificial diet offered, was adequate for the insects. The mean viability of the larval and ... (Complete abstract click electronic access below) / Doutor
39

Distribuição espacial e dinâmica populacional de Sphenophorus levis (Coleoptera: Curculionidae) em cana-de-açúcar

Izeppi, Tiago Sabongi [UNESP] 29 June 2015 (has links) (PDF)
Made available in DSpace on 2015-10-06T13:03:09Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-06-29. Added 1 bitstream(s) on 2015-10-06T13:18:53Z : No. of bitstreams: 1 000848680.pdf: 1393196 bytes, checksum: b6649096d280babc199fe3c920a2ea86 (MD5) / O conhecimento da dinâmica populacional e do padrão de distribuição de insetos em ecossistemas agrícolas é importante para o desenvolvimento de estratégias de manejo mais eficazes, auxiliando em uma melhor tomada de decisão. O objetivo deste trabalho foi estudar a distribuição espacial e a dinâmica populacional de Sphenophorus levis Vaurie (Coleoptera: Curculionidae) em cana-de-açúcar. No estudo da distribuição espacial, foram realizadas amostragens em 14 áreas comerciais de cana-de-açúcar, avaliando 100 pontos de amostragem por área, através de trincheiras na linha de cana de 50 x 50 x 30 cm, para contagem de larvas, pupas e adultos de S. levis e de seus danos, representados pela porcentagem de rizomas danificados pela praga. Nas áreas 6 a 14, na ocasião da amostragem, foram distribuídas iscas para contagem dos adultos presentes fora dos rizomas. A distribuição espacial foi estudada através da análise geoestatística. Para o estudo da dinâmica populacional, foi utilizada uma área comercial de cana soca em 2° corte cultivada com a variedade SP81-3250, no município de Américo Brasilense, SP. Foram feitas amostragens mensais através da abertura de 20 trincheiras na linha de cana, de 50 x 50 x 30 cm, para contagem de formas biológicas da praga presentes no rizoma (larvas, pupas e adultos). Nas mesmas ocasiões foram distribuídas na área 20 iscas, para contagem dos adultos. As larvas, formas biológicas totais (larvas + pupas + adultos) e o dano de S. levis distribuíram-se de maneira agregada, enquanto pupas e adultos distribuíram-se aleatoriamente em campo. Os valores de alcance obtidos e os mapas de interpolação por krigagem mostraram grande variabilidade das populações do inseto e seu dano em todas as áreas estudadas. Com base no alcance médio obtido para as variáveis estudadas, sugere-se que para estimar as populações do inseto e seu dano em canaviais os pontos de amostragem devem ser... / The knowledge of the population dynamics and insect distribution pattern in agricultural ecosystems is important for the development of more effective management strategies, assisting in better decision making. The objective of this work was to study the spatial distribution and population dynamics of Sphenophorus levis Vaurie (Coleoptera: Curculionidae) in sugarcane. In the study of spatial distribution, sampling was performed in 14 commercial areas of sugarcane, evaluating 100 sampling points per area through the trenches of 50 x 50 x 30 cm made in the line, for counting larvae, pupae, and S. levis adults and their damage, represented by the percentage of rhizomes damaged. In areas 6 to 14, at the time of sampling, baits were distributed for adult counts present outside the rhizomes. The spatial distribution was studied by geostatistical analysis. For the study of population dynamics, we used a commercial area of sugarcane in 2nd cut cultivated with SP81-3250 variety in the city of Américo Brasilense, SP. Monthly samples were taken through the opening 20 trenches in the cane row, 50 x 50 x 30 cm, for counting biological forms of pest present in the rhizome (larvae, pupae and adults). In the same occasion 20 baits were distributed in the area to count adults. The larvae, total biological forms (larvae + pupae + adults) and the damage S. levis were agregate, while pupae and adults distributed randomly in the field. The range of values obtained and the kriging interpolation maps showed large variability in insect populations and their damage in all studied areas. Based on the mid-range obtained for the variables studied, it is suggested that to estimate insect populations and their damage the sampling points should be spaced at 40 m. All the insect biological forms were found in the area during the year, however, the population peaks of adults occurred in rainy and warm time of year, in February and March, while larvae and pupae in more ...
40

Na trilha com as escoteiras: como operárias sabem o caminho a seguir

Silva, Mariana Brugger [UNESP] 27 February 2015 (has links) (PDF)
Made available in DSpace on 2016-09-27T13:39:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-02-27. Added 1 bitstream(s) on 2016-09-27T13:45:06Z : No. of bitstreams: 1 000869194_20170227.pdf: 88598 bytes, checksum: 97296f04daebe23bc211834a3445f60e (MD5) Bitstreams deleted on 2017-03-03T11:01:26Z: 000869194_20170227.pdf,. Added 1 bitstream(s) on 2017-03-03T11:02:37Z : No. of bitstreams: 1 000869194.pdf: 462579 bytes, checksum: 23c5f50ba256701378370a04d7dafd6b (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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