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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Dinâmica populacional, forrageamento e exposição de operárias de Ectatomma opaciventre (Hymenoptera : Formicidae) a iscas formicidas contendo sulfluramida, fipronil e clorpirifós

Tofolo, Viviane Cristina [UNESP] 20 January 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-01-20Bitstream added on 2014-06-13T19:25:15Z : No. of bitstreams: 1 tofolo_vc_dr_rcla_prot.pdf: 19466486 bytes, checksum: bad26d57e8eb11a239b119205310d9c6 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Ectatomma opaciventre (Hymenoptera: Formicidae: Ectatomminae) apresenta características morfológicas e comportamentais plesiomórficas, como a presença de um ferrão funcional, monoginia, colônias pequenas e estratégia de forrageamento solitário. Vive tanto nos ambientes preservados quanto nos alterados pelo homem, como os agroecossistemas, estando constantemente em contato com os produtos destinados ao controle de formigas consideradas pragas, como as cortadeiras do gênero Atta. Pouco se conhece a respeito de sua biologia básica (como dieta, rotas de forrageamento, distribuição espacial dos ninhos, composição dos hidrocarbonetos cuticulares) e das conseqüências advindas de seu contato com as iscas formicidas usadas para o controle de formigas cortadeiras em pastagens. Dessa forma, foi determinado por meio do “Método do Vizinho Mais Próximo” o padrão de distribuição espacial de seus ninhos em uma área degradada de 1800m2 na cidade de Rio Claro/SP/Brasil. Como na maioria das espécies de formigas tropicais, os ninhos de E. opaciventre apresentaram distribuição espacial do tipo regular ou hiperdispersa, com densidade de 0,018 ninho/m2. A distância média encontrada para o vizinho mais próximo foi de 5,57m, variando de 1,93m a 12,96m. Em vista da dificuldade em encontrar a rainha desta espécie, foi utilizado o método da “Espectroscopia Fotoacústica no Infravermelho com Transformada de Fourier (FTIR)” para identificar os hidrocarbonetos cuticulares da única rainha encontrada e das operárias de 9 ninhos satélites. Também foi determinado o grau de similaridade entre elas. Com os resultados obtidos ficou evidenciada a condição polidômica nessa espécie devido à semelhança entre o perfil químico cuticular da rainha e das operárias de ninhos vizinhos. Além disso... / Ectatomma opaciventre belongs to the subfamily Ectatomminae, which presents morphological and behavioral characteristics typical of more basal groups, such as the presence of a functional sting, monogyny, small colonies, and individual foraging strategies while searching for food. This species lives both in preserved and modified environments, such as agroecosystems, and it is constantly in contact with products intended to control ants regarded as pests, such as leaf-cutting ants of the genus Atta. The patterns of spatial distribution of nests over a 1800m2 degraded area in the city of Rio Claro, SP, Brazil were determined using a nearest neighbor method. As in most tropical species, the nests of E. opaciventre presented a regular or hyperdispersed spatial distribution, with a density of 0.018 nests/m2. The average nearest neighbor distance was 5.57 m, ranging from 1.93 m to 12.96 m. Considering the difficulty in finding queens of this species, the Fourier Transform-Infrared Photoacoustic Spectroscopy (FTIR-PAS) was used to identify cuticular hydrocarbons of the only queen found and of workers from nine satellite nests. The degree of similarity between them was also determined. From the results, polydomy was evident in this species because of the similarity between the cuticular chemical profile of the queen and that of workers from neighboring nests. Moreover, it was observed that the colonies that were not collected disappeared one year after the removal of the queen from the study area. In another area in the city of Rio Claro, of 4,800 m2, the diet of this species was studied by identifying the prey collected during the period of highest foraging activity. Besides, the foraging routes of three nests were determined by following foragers during their excursions in the field. The maximum foraging distance was... (Complete abstract click electronic access below)
2

Dinâmica populacional, forrageamento e exposição de operárias de Ectatomma opaciventre (Hymenoptera : Formicidae) a iscas formicidas contendo sulfluramida, fipronil e clorpirifós /

Tofolo, Viviane Cristina. January 2011 (has links)
Orientador: Edilberto Giannotti / Banca: Fabio Prezoto / Banca: Maria Santina de Castro Morini / Banca: Odair Correa Bueno / Banca: Claudio José Von Zuben / Resumo: Ectatomma opaciventre (Hymenoptera: Formicidae: Ectatomminae) apresenta características morfológicas e comportamentais plesiomórficas, como a presença de um ferrão funcional, monoginia, colônias pequenas e estratégia de forrageamento solitário. Vive tanto nos ambientes preservados quanto nos alterados pelo homem, como os agroecossistemas, estando constantemente em contato com os produtos destinados ao controle de formigas consideradas pragas, como as cortadeiras do gênero Atta. Pouco se conhece a respeito de sua biologia básica (como dieta, rotas de forrageamento, distribuição espacial dos ninhos, composição dos hidrocarbonetos cuticulares) e das conseqüências advindas de seu contato com as iscas formicidas usadas para o controle de formigas cortadeiras em pastagens. Dessa forma, foi determinado por meio do "Método do Vizinho Mais Próximo" o padrão de distribuição espacial de seus ninhos em uma área degradada de 1800m2 na cidade de Rio Claro/SP/Brasil. Como na maioria das espécies de formigas tropicais, os ninhos de E. opaciventre apresentaram distribuição espacial do tipo regular ou hiperdispersa, com densidade de 0,018 ninho/m2. A distância média encontrada para o vizinho mais próximo foi de 5,57m, variando de 1,93m a 12,96m. Em vista da dificuldade em encontrar a rainha desta espécie, foi utilizado o método da "Espectroscopia Fotoacústica no Infravermelho com Transformada de Fourier (FTIR)" para identificar os hidrocarbonetos cuticulares da única rainha encontrada e das operárias de 9 ninhos satélites. Também foi determinado o grau de similaridade entre elas. Com os resultados obtidos ficou evidenciada a condição polidômica nessa espécie devido à semelhança entre o perfil químico cuticular da rainha e das operárias de ninhos vizinhos. Além disso... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Ectatomma opaciventre belongs to the subfamily Ectatomminae, which presents morphological and behavioral characteristics typical of more basal groups, such as the presence of a functional sting, monogyny, small colonies, and individual foraging strategies while searching for food. This species lives both in preserved and modified environments, such as agroecosystems, and it is constantly in contact with products intended to control ants regarded as pests, such as leaf-cutting ants of the genus Atta. The patterns of spatial distribution of nests over a 1800m2 degraded area in the city of Rio Claro, SP, Brazil were determined using a nearest neighbor method. As in most tropical species, the nests of E. opaciventre presented a regular or hyperdispersed spatial distribution, with a density of 0.018 nests/m2. The average nearest neighbor distance was 5.57 m, ranging from 1.93 m to 12.96 m. Considering the difficulty in finding queens of this species, the Fourier Transform-Infrared Photoacoustic Spectroscopy (FTIR-PAS) was used to identify cuticular hydrocarbons of the only queen found and of workers from nine satellite nests. The degree of similarity between them was also determined. From the results, polydomy was evident in this species because of the similarity between the cuticular chemical profile of the queen and that of workers from neighboring nests. Moreover, it was observed that the colonies that were not collected disappeared one year after the removal of the queen from the study area. In another area in the city of Rio Claro, of 4,800 m2, the diet of this species was studied by identifying the prey collected during the period of highest foraging activity. Besides, the foraging routes of three nests were determined by following foragers during their excursions in the field. The maximum foraging distance was... (Complete abstract click electronic access below) / Doutor
3

Survey of different mealybug species and attending ants and their management in Virginia vineyards

Chalise, Pragya 01 November 2023 (has links)
Mealybugs (Order Hemiptera: Superfamily Coccoidea) represent a persistent problem in grape-growing regions globally, with a notable increase in infestations in recent times. The current study investigates the species composition and seasonal dynamics of mealybugs in vineyards. Pseudococcus maritimus and Ferissia gilli remain the dominant species, while Pseudococcus viburni was also spotted during two separate instances and Planococcus ficus remained absent. Commercially available pheromone delta traps and adhesive bands were deployed to capture the male mealybugs, while numerically higher efficacy was observed in the adhesive band trap. Notably, the placement of adhesive band traps on the cordon and trunk revealed differential male mealybug captures, probably indicating their movement within the vines. The research also divulges into the life cycle of mealybugs and their population densities during the sampling season. The main highlight has been the lower population density of earlier nymphal stages of the first generation of mealybugs followed by the colonization of grapevines by the second-generation crawlers. Adults of second generations give rise to the overwintering stages of mealybugs. Traditionally the research also explores the species and seasonal population dynamics of ants along with mealybugs and their management in Virginia vineyards. The activity of fifteen genera of ants in the vineyard was recorded, with some of the dominant ant genera like Tetramorium, Crematogaster, and Lasius were recorded in the vineyard actively tending and defending the mealybugs and moving them around. Fruit cluster infestation was also higher in the control treatment in comparison to sugar dispenser and ant bait dispenser treatments. This comprehensive assessment of ant diversity further deepens our understanding of the intricate ecosystem within vineyards. A spray trial using three different insecticides with distinct modes of action (Buprofezin, Bifenthrin, and Spirotetramat) in two of the commercial vineyards. Preliminary results indicate that on some days after treatment, insecticides effectively controlled mealybug populations, offering a glimmer of hope to vineyard owners grappling with infestations. Mealybugs pose a significant threat to grape cultivation, and this research provides valuable insights that can help vineyard owners and grape growers develop more targeted and effective control strategies. Species identification, understanding their behavior, and exploring potential allies in the fight against mealybugs are all crucial steps toward maintaining the health and productivity of vineyards in Virginia. While challenges remain in the battle against mealybugs, this research marks a significant step forward in safeguarding grape cultivation in Virginia and potentially reshaping strategies for controlling these persistent pests in vineyards. Growers and researchers alike eagerly await further developments and the practical application of these findings to protect the flourishing vineyards of the region. / Doctor of Philosophy / Mealybugs are common grapevine pests, recently causing a nuisance in vineyards across the United States and Canada. Some of the previously documented species of mealybugs common in the eastern part of the States include grape mealybug, obscure mealybug, Gill's mealybug, and long-tailed mealybugs. The research has mainly addressed the mealybugs and their tending ant species and their management in vineyards in Virginia. The study identifies grape mealybug and Gill's mealybug as the dominant species with occasional sightings of obscure mealybug and a lack of vine mealybug throughout the sampled vineyard sites. The male mealybugs were monitored using commercially available pheromone delta traps and adhesive band traps. Placement of adhesive band traps in the cordon and trunk of grapevines revealed different male mealybug capture data suggesting their movement within the grapevines. Two generations of mealybugs including the first generation with lower population density emerging out from the overwintering life-stage and the subsequent second generation responsible for colonizing different parts of the grapevines and producing overwintering life-stages were observed. Fifteen genera of ants were sampled from the vineyard via pitfall trap with some ants like pavement ants, acrobat ants, and medium garden ants actively tending and protecting the mealybugs. The use of sugar dispensers in the vineyards also led to lower fruit cluster infestations with mealybugs in comparison to the area without dispensers. The insecticidal spray trial using three different insecticides was also effective in controlling populations of mealybugs on some of the dates after treatment. The research offers valuable insights for grape growers, aiding in the development of effective control strategies for mealybug control. It emphasizes the importance of identifying the species present, understanding their behavior, and exploring potential allies and insecticide options in pest management.

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