Dissertations / Theses on the topic 'Insect populations'
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Banks, John E. "The effects of landscape heterogeneity on insect populations : a study of pattern and scale /." Thesis, Connect to this title online; UW restricted, 1997. http://hdl.handle.net/1773/5166.
Full textHiggins, Charlene J. "Spatial distribution and reproductive biology of western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera : Thripidae)." Thesis, University of British Columbia, 1991. http://hdl.handle.net/2429/29873.
Full textScience, Faculty of
Zoology, Department of
Graduate
Hitchman, Richard B. "Pathogen variability and dynamics in insect populations." Thesis, Oxford Brookes University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.247600.
Full textLatto, John. "The analysis of density dependence in insect populations." Thesis, Imperial College London, 1989. http://hdl.handle.net/10044/1/47531.
Full textMcNamee, Peter James. "The equilibrium structure and behavior of defoliating insect systems." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/27439.
Full textScience, Faculty of
Zoology, Department of
Graduate
Ballard, Meg. "Insect populations on early successional native and alien plants." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 50 p, 2006. http://proquest.umi.com/pqdweb?did=1203553531&sid=1&Fmt=2&clientId=8331&RQT=309&VName=PQD.
Full textGaston, K. J. "Patterns in the dynamics and distribution of insect populations." Thesis, University of York, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.235013.
Full textWilcock, Helen Rachel. "Geographic and genetic structure of highly fragmented freshwater insect populations." Thesis, Queen Mary, University of London, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.481520.
Full textMorrison, Peter D. S. "Host plant variation and population limitation of two introduced insects." Thesis, University of British Columbia, 1986. http://hdl.handle.net/2429/27464.
Full textScience, Faculty of
Zoology, Department of
Graduate
Chu, C. C., and T. J. Henneberry. "Cultural Control and Pink Bollworm Populations." College of Agriculture, University of Arizona (Tucson, AZ), 1996. http://hdl.handle.net/10150/210914.
Full textKowles, Katelyn A. "Dynamics of aggregation formation in Japanese beetles, Popillia japonica /." View online, 2009. http://repository.eiu.edu/theses/docs/32211131559299.pdf.
Full textSinka, Marianne. "The ecological effects of above-ground insect herbivores on Collembola populations." Thesis, Imperial College London, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.407404.
Full textHackett, Sean. "The optimal control of dynamic pest populations." Thesis, University of Oxford, 2018. http://ora.ox.ac.uk/objects/uuid:5035e7a5-1d81-4288-8eb0-ec05b2fd95a2.
Full textBright, Jennifer Anne. "Insects on farmland and their importance to granivorous birds." Thesis, University of Stirling, 2004. http://hdl.handle.net/1893/2158.
Full textSteffan, Shawn Alan. "Biodiversity and fear ecology the cascading effects of species richness and nontrophic interactions /." Pullman, Wash. : Washington State University, 2009. http://www.dissertations.wsu.edu/Dissertations/Spring2009/s_steffan_041709.pdf.
Full textSantos, Luan Alberto Odorizzi dos. "Contribution of marginal non-crop vegetation and semi-natural habitats to the regulation of insect pest populations by their natural enemies /." Jaboticabal, 2017. http://hdl.handle.net/11449/150943.
Full textCoorientador: Armin Bischoff
Banca: Pierre Franck
Banca: Daniel Junior de Andrade
Banca: Olivier Blight
Banca: Raphael de Campos Castilho
Abstract: The expansion of agricultural areas has led to the loss of biodiversity due to the reduction of natural and semi-natural habitats in agricultural landscapes. With the increase of agricultural production in the world, environmentally sound techniques are increasingly discussed that allow a sustainable management of surrounding habitats. The effects of these habitats on the population of insect pests and their natural enemies are still poorly understood. The objective of this thesis was to understand the effects of natural and semi-natural environments on the population of insect pests and natural enemies in tropical (Brazil) and temperate (France) regions. In Brazil (Chapter II) the effect of the distance of fragments on the population of predatory and omnivorous ants in sugarcane was evaluated. The results showed that the species richness decrease with distance from forest fragments and that the dominance of the species Dorymyrmex bruneus and Pheidole oxyops increase. Ant species colonizing sugarcane fields were also found in forest fragments suggesting that the latter habitats are refuges for predatory ant species during periods of disturbance such as sugarcane harvest or soil tillage. This was confirmed by stronger differences in ant communities after sugarcane harvest (dry season) than four months later (rainy season) when absence of disturbance allowed re-colonosiation by ants. There was also a difference in the richness of ant species between different fragment types (ri... (Complete abstract click electronic access below)
Résumé: L'expansion des zones agricoles a conduit à la perte de biodiversité due à la réduction des habitats naturels et semi-naturels dans les paysages agricoles. Avec l'augmentation de la production agricole dans le monde, des techniques écologiquement rationnelles sont de plus en plus discutées qui permettent une gestion durable des habitats environnants. Les effets de ces habitats sur la population des insectes nuisibles et de leurs ennemis naturels sont encore mal connus. L'objectif de cette thèse était de comprendre les effets des environnements naturels et semi-naturels sur la population des insectes nuisibles et des ennemis naturels dans les régions tropicales (Brésil) et tempérées (France). Au Brésil (chapitre II), on a évalué l'effet de la distance des fragments sur la population de fourmis prédatrices et omnivores dans la canne à sucre. Les résultats montrent que la richesse en espèces diminue avec la distance des fragments forestiers et que la prédominance des espèces Dorymyrmex bruneus et Pheidole oxyops augmente. Des espèces de fourmis colonisant les champs de canne à sucre ont également été trouvées dans des fragments forestiers, ce qui suggère que ces derniers habitats sont des refuges pour les espèces de fourmis prédatrices pendant les périodes de perturbation comme la récolte de la canne à sucre ou le travail du sol. Cela a été confirmé par des différences plus fortes dans les communautés de fourmis après la récolte de la canne à sucre (saison sèche) que quatre mois... (Résumé complet accès életronique ci-dessous)
Resumo: A expansão das áreas agrícolas levou à perda de biodiversidade devido à redução dos habitats naturais e semi-naturais nas paisagens agrícolas. Com o aumento da produção agrícola no mundo, são cada vez mais discutidas técnicas ambientais que permitem uma gestão sustentável dos habitats do entorno. Os efeitos desses habitats sobre a população de insetos-pragas e seus inimigos naturais ainda são mal compreendidos. O objetivo desta tese foi compreender os efeitos dos ambientes naturais e semi-naturais na população de insetos-pragas e inimigos naturais nas regiões tropicais (Brasil) e temperadas (França). No Brasil (Capítulo II) foi avaliado o efeito da distância de fragmentos sobre a população de formigas predadoras e omnívoras em cana-de-açúcar. Os resultados mostraram que a riqueza de espécies diminui com a distância dos fragmentos florestais e que a dominância das espécies Dorymyrmex bruneus e Pheidole oxyops aumenta. As espécies de formigas que colonizam áreas de cana-de-açúcar também foram encontradas em fragmentos de florestas, sugerindo que estes últimos são abrigos para espécies de formigas predatórias durante períodos de perturbação como colheita de cana-de-açúcar ou preparo do solo. Isto foi confirmado por diferenças mais fortes nas comunidades de formigas após a colheita da cana (estação seca) do que quatro meses depois (estação chuvosa) quando a ausência de perturbação permitiu recolonização por formigas. Houve também uma diferença na riqueza de espécies de formigas e... (Resumo completo, clicar acesso eletrônico abaixo)
Doutor
Butler, G. D. Jr, T. J. Henneberry, and H. H. Jr Perkins. "Sweetpotato Whitefly Populations in Cotton Genotypes at Poston, Arizona in 1988." College of Agriculture, University of Arizona (Tucson, AZ), 1990. http://hdl.handle.net/10150/208312.
Full textWatson, T. F., J. C. Silvertooth, and A. Tellez. "Varietal and Nitrogent-level Effects on Sweepotato Whitefly Populations in Cotton." College of Agriculture, University of Arizona (Tucson, AZ), 1994. http://hdl.handle.net/10150/209646.
Full textNaranjo, Steven E., and Peter C. Ellsworth. "Mortality Factors Affecting Whitefly Populations in Arizona Cotton Management Systems: Life Table Analysis." College of Agriculture, University of Arizona (Tucson, AZ), 1999. http://hdl.handle.net/10150/197274.
Full textHenneberry, T. J., T. Meng, B. Deeter, and P. Price. "Effects of PREP on Cotton Fruiting, Boll Opening and Boll Weevil Populations." College of Agriculture, University of Arizona (Tucson, AZ), 1987. http://hdl.handle.net/10150/204494.
Full textRethwisch, Michael D., Mark Reay, Lois Berger, Erica Hawpe, Jessica Grudovich, Roger Perez, and David Ramos. "Comparisons of Insecticides on Fall Alfalfa Insect Populations, and Resultant Hay Yields and Quality." College of Agriculture, University of Arizona (Tucson, AZ), 2004. http://hdl.handle.net/10150/203869.
Full textRethwisch, Michael D., Marvin D. Butler, and Mike Meadows. "Evaluation of Head Lettuce Varieties for Liriomyza trifolii Leafminer Populations." College of Agriculture, University of Arizona (Tucson, AZ), 1989. http://hdl.handle.net/10150/214266.
Full textSilva, Ivana Fernandes da 1986. "Desempenho de populações geográficas de Helicoverpa armigera (Hübner) (Lepidoptera : Noctuidae) em dietas naturais e artificial e caracterização por microssatélites /." Botucatu, 2017. http://hdl.handle.net/11449/150891.
Full textCoorientador: 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
Osman, Abdelgadir A., Theo F. Watson, and Sakunlala Sivasupramaniam. "Susceptibility of Field Populations of Pink Bollworm (Lepidoptera: Gelechiidae) to Azinphosmethyl and Permethrin." College of Agriculture, University of Arizona (Tucson, AZ), 1991. http://hdl.handle.net/10150/208354.
Full textKadango, Tendayi Lovemore. "Farmers' perceptions of insect pests in the Eastern Cape maize-based cropping systems and the effects of crop residue management on insect pest populations." Thesis, University of Fort Hare, 2018. http://hdl.handle.net/10353/6202.
Full textBlochel, Alexander. "Population demography’s potential effect on stoichiometry : Assessing the growth rate hypothesis with demography." Thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-130908.
Full textKnowles, Katherine L. Jr. "Impact of Low-Spray Mating Disruption Programs on Aphidophagous Insect Populations in Virginia Apple Orchards." Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/31098.
Full textMaster of Science
Coetzee, J. H. (Jacobus Hendrik). "Arthropod communities of Proteaceae with special emphasis on plant-insect interactions." Thesis, Stellenbosch : Stellenbosch University, 1989. http://hdl.handle.net/10019.1/66615.
Full textENGLISH ABSTRACT: Arthropod communities of five proteaceous species viz. Protea repens. P. neriifolia. P.cynaroides, Leucospermum cordifolium and Leucadendron /aureolum were studied. A faunal list of the insects was compiled according to the feeding guilds of insects. Six phytophagous guilds were recognized: flower visitors, thrips, endophages, ectophages, sap-suckers, and ants. The guild composition, species packing and seasonal distribution for the free-IMng insects, spiders and other arthropods were investigated on the different plant species. The ants, flower visitors and sap-sucking species found on the plant species, were very similar, but the number of leaf chewing species common to all the plant species was low, suggesting that some species were monophagous. Insect abundance increased during the wet winter months when the plants were in flower. Of the total number of herbivores collected, flower visitors represented 69,5%, leaf feeders 14,5% and sap-suckers 16,1 %. The chewers constituted 60,1% of the total herbivore. biomass. Leaf damage increased with age ; young leaves were practically free of herbivore damage, while older leaves were stm acceptable as food. The degree of insect damage differed amongst the plant species varying from 2% to 15%. The following leaf characteristics were investigated to determine the factors involved in defence against insect herbivory : total phenolic content, protein precipitating ability, cyanogenesis, nitrogen content, leaf toughness, woodiness and fibre content lt appears that the plant species use different mechanisms to protect their leaves. The infructescences of Protea repens were exploited by the larvae of four Coleoptera and four Lepidoptera species. The community structure of these phytophagous insects was determined largely by negative interactions. Various strategies are followed (e.g. niche segregation in time and space) to lessen interspecific competition.
AFRIKAANSE OPSOMMING: 'n Studie van die arthropoocl gemeenskap op vyf proteasoorte, naamlik Protea repens. P. neriffolia. P. cynaroides. Leucospennum cordffolium en Leucadendron laureolum is gedoen. 'n Faunalys van insekte volgens hul voedingsgDdes is saamgestel. Die insekte is in ses fitofage gDdes verdeel naamlik blombesoekers, blaaspootjies, endovoeders, ektovoeders, sapsuiers en miere. Die samestelling van die gDdes, spesie-rangskikking en seisoenale verspreiding is bepaal vir die vrylewende insekte, spinnekoppe en ander arthropode. Die miere, blombesoekers en sapsuierspesies wat op die plantsoorte gevind is, is byna dieselfde, maar verslalle in die blaarvoederspesies is gevind wat 'n aanduiding is dat sommige spesies monofaag mag wees. Gedurende die nat wintermaande toon die insekgetalle 'n toename. Blombesoekers verteenwoordig 69,5%, blaarvoeders 14,5% en sapsuiers 16,1% van die aantal insekherbivore wat versamel is. Die kouers vorm 60,1% van die totale herbivoor biomassa Soos die blare verouder, neem die skade op die blare toe; jong blare toon byna geen skade nie, terwyl ouer blare steeds geskik is vir insekvoedsel. Die insekskade op die blare wissel by die verslallende plante tussen 2% en 15%. Om te bepaal watter blaareienskappe moontlik 'n rol kan speel in blaarverdediging teen insekte is die volgende ondersoek: totale fenoliese inhoud, die vermoe om proteiene te presipiteer, sianogenese. stikstofinhoud, blaartaaiheid, houtagtigheid en veselinhoud. Dit wil voorkom asof die plante verskillende meganismes gebruik om die blare te beskerm. Saadkoppe van Protea repens word deur vier Coleoptera en vier Lepidoptera spesies benut Die gemeenskapstruktuur van die boarders word tot 'n groat mate bepaal deur negatiewe interaksies. Verskeie strategiee word gevolg (bv. nissegregasie in ~ en ruimte) om kompetisie tussen spesies te verminder.
Izeppi, Tiago Sabongi [UNESP]. "Distribuição espacial e dinâmica populacional de Sphenophorus levis (Coleoptera: Curculionidae) em cana-de-açúcar." Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/128076.
Full textO 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 ...
Izeppi, Tiago Sabongi. "Distribuição espacial e dinâmica populacional de Sphenophorus levis (Coleoptera: Curculionidae) em cana-de-açúcar /." Jaboticabal, 2015. http://hdl.handle.net/11449/128076.
Full textCoorientador: 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
Dennehy, T. J., G. C. Cramer, and J. DeBolt. "Susceptibility of Arizona Populations of Lygus Bugs to Acephate (Orthene®) and Bifenthrin (Capture®)." College of Agriculture, University of Arizona (Tucson, AZ), 1995. http://hdl.handle.net/10150/210324.
Full textHenneberry, T. J., L. A. Bariola, J. E. Leggett, T. Meng, D. Akey, and B. Deeter. "Report on the Effect of PREP on Cotton Fruiting, Boll Opening, and Boll Weevil Populations." College of Agriculture, University of Arizona (Tucson, AZ), 1986. http://hdl.handle.net/10150/219768.
Full textButler, G. D., B. A. Kimball, and J. R. Mauney. "Populations of the Sweetpotato Whitefly on Cotton Grown in Open-Top Field Carbon Dioxide-Enrichment Chambers." College of Agriculture, University of Arizona (Tucson, AZ), 1985. http://hdl.handle.net/10150/204054.
Full textYoung, Belinda. "Selective Harvesting in Headwater Streams: Investigating the Effects of Habitat Discontinuity on Adult Aquatic Insect Populations." Thesis, Griffith University, 2012. http://hdl.handle.net/10072/367775.
Full textThesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Science, Environment, Engineering and Technology
Full Text
Terry, L. I., J. C. Silvertooth, and C. Summers. "Effect of Date of Planting and Irrigation Termination on Pink Bollworm Populations in Pima and Upland Cotton." College of Agriculture, University of Arizona (Tucson, AZ), 1990. http://hdl.handle.net/10150/208314.
Full textChu, Chang-chi, Thomas J. Henneberry, Louis A. Bariola, and Brian Deeter. "Effect of Plant Growth Regulators Under Short-Season Conditions on Pink Bollworm Populations, Cotton Yields and Defoliation." College of Agriculture, University of Arizona (Tucson, AZ), 1991. http://hdl.handle.net/10150/208370.
Full textAnderson, Robert Derek. "Reducing orthophosphates in retention ponds and its impact on larval mosquito abundance." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 98 p, 2007. http://proquest.umi.com/pqdweb?did=1397903371&sid=5&Fmt=2&clientId=8331&RQT=309&VName=PQD.
Full textBronzato, Aline Ribeiro [UNESP]. "Análise da estrutura populacional de Aedes aegytpi (Linnaeus, 1762) em algumas regiões do Brasil." Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/144079.
Full textCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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...
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...
Bronzato, Aline Ribeiro. "Análise da estrutura populacional de Aedes aegytpi (Linnaeus, 1762) em algumas regiões do Brasil." Botucatu, 2015. http://hdl.handle.net/11449/144079.
Full textBanca: 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
Palumbo, John, Clayton Jr Mullis, Francisco Reyes, and Andreas Amaya. "Timing and Frequency of Provado® Applications for Management of Aphid Populations in Head Lettuce." College of Agriculture, University of Arizona (Tucson, AZ), 1996. http://hdl.handle.net/10150/214752.
Full textDennehy, T. J., and T. J. Russell. "Susceptibility of Lygus Bug Populations in Arizona to Acephate (Orthene®) and Bifenthrin (Capture®), with Related Contrasts of Other Insecticides." College of Agriculture, University of Arizona (Tucson, AZ), 1996. http://hdl.handle.net/10150/210912.
Full textBedet, Charlotte. "Soil fertility, crop nutrients, weed biomass and insect populations in organic and conventional field corn (Zea mays L.) agroecosystems /." The Ohio State University, 2000. http://rave.ohiolink.edu/etdc/view?acc_num=osu1488196781734832.
Full textNarita, Nobuyoshi 1961. "Epidemiologia do "Cowpea aphid borne mosaic virus" (CABMV) em maracujazeiros na região produtora da Alta Paulista, SP /." Botucatu : [s.n.], 2007. http://hdl.handle.net/11449/103210.
Full textAbstract: From the viruses were described infecting passionfruit plants in Brasil, and the Cowpea aphid borne mosaic virus (CABMV), is considered the most hazardous. Depending on the spread velocity of aphids and the age that the plants are infected, the crops doesnt produce commercial fruits. The present study was designed to evaluate the diversity and dynamic population of aphids in the Alta Paulista, SP region and aspects of seed transmission. For this, four regions (East and West of Marília city, Guaimbê and Ocauçú) were monitored for 24 months using yellow water Moerick trap. The predominance of the genus Aphis was observed in the four evaluated areas. Other species founded in the area were: Myzus persicae, Geopenphigus flocculosus, Brevicoryne brassicae, Rhopalosiphum spp, Dysaphis spp and Lipaphis erysimi. The population curve of alate Aphis spp showed the highest frequency of flights during May, June, August and September. The Aphis spp (A. fabae, A. gossypii, A. spiraecola) probably is the most important vector of the CABMV in the region. New crops near old infected plants, were infected in three months. To evaluate properties of seed transmission, from 13056 collected from infected plants, 10592 were germinated and evaluated during two months for the presence of visual symptoms. No plants with simptoms were observed indicating no seed transmission.
Orientador: Marcelo Agenor Pavan
Coorientador: Valdir Atsushi Yuki
Banca: Renate Krause Sakate
Banca: Aloisio Costa Sampaio
Banca: Alexandre Levi R. Chaves
Banca: Hugo Kuniyuki
Doutor
Schultheis, Alicia Slater. "Gene Flow and Dispersal Among Populations of the Stonefly Peltoperla tarteri (Plecoptera: Peltoperlidae) in the Southern Appalachians." Diss., Virginia Tech, 2000. http://hdl.handle.net/10919/29750.
Full textPh. D.
Modelski, Kimberly A. "Comparison of climatic conditions and mosquito abundances in New Castle County, Delaware." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file 3.25 Mb., 229 p, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:1435830.
Full textDoublet, Violette. "Interactions biotiques et dynamiques des populations : approches empiriques et théoriques de la prédation pré-dispersion des graines par les insectes." Thesis, Montpellier, 2020. http://www.theses.fr/2020MONTG007.
Full textBiotic interactions are among key processes in population dynamics and critical issues for the renewal and persistence of species within ecosystems. In particular, herbivory by pre-dispersal seed insect predators is a major ecological process in forest dynamics due to its impact on tree reproductive success and on natural regeneration. However, its consequence on tree population dynamics and evolution remain poorly documented. This thesis contributed to fill this gap as an integrative combination of empirical and theoretical approaches. The empirical approach aimed to characterize the drivers of the spatio-temporal dynamics of seed predation rates in natural forest. We used a system of tree-insect interactions involving seed predators (Megastigmus spp., Hymenoptera: Torymidae) and their obligate host, the Atlas Cedar (Cedrus atlantica, Pinaceae), located in south-eastern France. At the host population scale, our results revealed that the transient pattern of the spatial distribution of insects was primarily explained by spatiotemporal variations in seed density. Thus, Cedar masting appeared to be a major driving force of the insects’ spatial and temporal dynamics. We have also highlighted the existence of an inter-individual variation in the sensitivity of trees to seed predation. A preliminary analysis has suggested that such variation is partly under genetic control and we propose further analyses to be carried out in such perspective. The theoretical approach aimed to analyse the joint effects of masting and the spatial distribution of pre-dispersal seed predation by insects on demographic processes and genetic diversity in an expanding tree population. The analytical modelling of these interactions revealed on the one hand that pre-dispersal seed predation induce Allee effects that may affect the spatial structure of genetic diversity in the expanding tree population, and on the other hand, that masting was likely to buffer such demogenetic impact of seed predation. This work has shed new light on the possible implications of pre-dispersal predation by insects in the dynamics and evolution of forests
Santos, Luan Alberto Odorizzi dos [UNESP]. "Contribution of marginal non-crop vegetation and semi-natural habitats to the regulation of insect pest populations by their natural enemies." Universidade Estadual Paulista (UNESP), 2017. http://hdl.handle.net/11449/150943.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
L'expansion des zones agricoles a conduit à la perte de biodiversité due à la réduction des habitats naturels et semi-naturels dans les paysages agricoles. Avec l'augmentation de la production agricole dans le monde, des techniques écologiquement rationnelles sont de plus en plus discutées qui permettent une gestion durable des habitats environnants. Les effets de ces habitats sur la population des insectes nuisibles et de leurs ennemis naturels sont encore mal connus. L'objectif de cette thèse était de comprendre les effets des environnements naturels et semi-naturels sur la population des insectes nuisibles et des ennemis naturels dans les régions tropicales (Brésil) et tempérées (France). Au Brésil (chapitre II), on a évalué l'effet de la distance des fragments sur la population de fourmis prédatrices et omnivores dans la canne à sucre. Les résultats montrent que la richesse en espèces diminue avec la distance des fragments forestiers et que la prédominance des espèces Dorymyrmex bruneus et Pheidole oxyops augmente. Des espèces de fourmis colonisant les champs de canne à sucre ont également été trouvées dans des fragments forestiers, ce qui suggère que ces derniers habitats sont des refuges pour les espèces de fourmis prédatrices pendant les périodes de perturbation comme la récolte de la canne à sucre ou le travail du sol. Cela a été confirmé par des différences plus fortes dans les communautés de fourmis après la récolte de la canne à sucre (saison sèche) que quatre mois plus tard / (saison des pluies) quand l'absence de perturbation a permis la re-lonosiation par les fourmis. Il y avait aussi une différence dans la richesse des espèces de fourmis entre les différents types de fragments (vallées fluviales et plaines). En France, on a évalué l'effet des bandes de fleurs sauvages, de la végétation spontanée et des bandes d'herbe sur la communauté des ennemis naturels et la régulation du puceron de la pomme rosâtre Dysaphis plantaginaea (chapitre III). En ce qui concerne les principaux ennemis naturels, nos résultats ont montré une densité plus élevée de hoverflies par rapport à d'autres types de bande, mais aucune différence pour les coccinelles (coccinelidae). Cependant, aucune différence de densité naturelle de l'ennemi n'a été observée à l'intérieur des vergers. Le nombre de pucerons était plus élevé près des marges, ce qui suggère que la colonisation à partir des bandes marginales peut contrecarrer les effets régulateurs positifs des ennemis naturels. Les effets positifs de la végétation de la marge de bande sur la régulation des ravageurs de la pomme nécessitent un mouvement d'ennemis naturels dans le verger. Nous avons testé les mouvements des prédateurs généralistes en étiquetant les bandes de marge avec des protéines d'oeufs et nous avons vérifié si elles se nourrissaient d'insectes nuisibles en utilisant l'analyse de marqueurs génétiques des gènes de papillon (Cydia pomonella) à l'intérieur des prédateurs (chapitre IV). Les résultats ont montré que peu de personnes se déplaçaient des marges de champ dans le verger. Cependant, 25% des prédateurs capturés se nourrissaient de C. pomonella indiquant encore un haut niveau de régulation naturelle. En conclusion, le mouvement limité des prédateurs à partir des bandes de marges dans les vergers peut expliquer l'absence de différences entre les traitements de bandes dans la régulation des ravageurs du verger (pucerons). Les habitats naturels et semi-naturels peuvent contribuer à la lutte contre les ravageurs en marge des cultures, mais dans les vergers de pommiers cet effet a fortement diminué avec la distance.
A expansão das áreas agrícolas levou à perda de biodiversidade devido à redução dos habitats naturais e semi-naturais nas paisagens agrícolas. Com o aumento da produção agrícola no mundo, são cada vez mais discutidas técnicas ambientais que permitem uma gestão sustentável dos habitats do entorno. Os efeitos desses habitats sobre a população de insetos-pragas e seus inimigos naturais ainda são mal compreendidos. O objetivo desta tese foi compreender os efeitos dos ambientes naturais e semi-naturais na população de insetos-pragas e inimigos naturais nas regiões tropicais (Brasil) e temperadas (França). No Brasil (Capítulo II) foi avaliado o efeito da distância de fragmentos sobre a população de formigas predadoras e omnívoras em cana-de-açúcar. Os resultados mostraram que a riqueza de espécies diminui com a distância dos fragmentos florestais e que a dominância das espécies Dorymyrmex bruneus e Pheidole oxyops aumenta. As espécies de formigas que colonizam áreas de cana-de-açúcar também foram encontradas em fragmentos de florestas, sugerindo que estes últimos são abrigos para espécies de formigas predatórias durante períodos de perturbação como colheita de cana-de-açúcar ou preparo do solo. Isto foi confirmado por diferenças mais fortes nas comunidades de formigas após a colheita da cana (estação seca) do que quatro meses depois (estação chuvosa) quando a ausência de perturbação permitiu recolonização por formigas. Houve também uma diferença na riqueza de espécies de formigas entre diferentes tipos de fragmentos (vales de rios e planícies). Na França, foi avaliado o efeito de faixas de flores silvestres, vegetação espontânea e gramíneas na comunidade de inimigos naturais e a regulação do pulgão cinza Dysaphis plantaginaea (Capítulo III). No que diz respeito aos principais inimigos naturais, os nossos resultados mostraram uma maior densidade de sirfideos nas faixas de flores em comparação com outros tipos de faixas, mas nenhuma diferença para joaninha (Coccinelidae). Não foram observadas diferenças nas densidades de inimigos naturais dentro dos pomares. O número de afídeos foi maior perto das margens, sugerindo que a colonização das faixas nas margens pode neutralizar os efeitos reguladores positivos dos inimigos naturais. Os efeitos positivos da vegetação nas faixas da margem na regulação de pragas da maçã requerem um movimento de inimigos naturais no pomar. Nós testamos os movimentos de predadores generalistas marcando as faixas das margens com proteína de ovo e verificamos se eles se alimentavam de insetos pragas usando a análise de marcadores moleculares de genes de mariposas (Cydia pomonella) nos predadores (capítulo IV). Os resultados mostraram que poucos indivíduos se movimentaram das margens do campo para o pomar. No entanto, 25% dos predadores capturados alimentados com C. pomonella ainda indicam um alto nível de regulação natural. Em conclusão, o movimento limitado de predadores das faixas de plantas nas margens em pomares pode explicar a ausência de diferenças entre os tratamentos na regulação de pragas do pomar (pulgões). Habitats naturais e semi-naturais podem contribuir para o controle de pragas nas margens das culturas, mas em pomares de maçã este efeito diminuiu fortemente com a distância.
The expansion of agricultural areas has led to the loss of biodiversity due to the reduction of natural and semi-natural habitats in agricultural landscapes. With the increase of agricultural production in the world, environmentally sound techniques are increasingly discussed that allow a sustainable management of surrounding habitats. The effects of these habitats on the population of insect pests and their natural enemies are still poorly understood. The objective of this thesis was to understand the effects of natural and semi-natural environments on the population of insect pests and natural enemies in tropical (Brazil) and temperate (France) regions. In Brazil (Chapter II) the effect of the distance of fragments on the population of predatory and omnivorous ants in sugarcane was evaluated. The results showed that the species richness decrease with distance from forest fragments and that the dominance of the species Dorymyrmex bruneus and Pheidole oxyops increase. Ant species colonizing sugarcane fields were also found in forest fragments suggesting that the latter habitats are refuges for predatory ant species during periods of disturbance such as sugarcane harvest or soil tillage. This was confirmed by stronger differences in ant communities after sugarcane harvest (dry season) than four months later (rainy season) when absence of disturbance allowed re-colonosiation by ants. There was also a difference in the richness of ant species between different fragment types (river valleys and plateaus). In France, the effect of wildflower strips, spontaneous vegetation and grass strips on the community of natural enemies and the regulation of the rosy apple aphid Dysaphis plantaginaea (Chapter III) were evaluated. Concerning major natural enemies, our results showed a higher density of hoverflies in wild flower strips compared with other strip types but no differences for ladybirds (coccinelidae). However, no differences in natural enemy densities were observed inside orchards. Aphid number was higher close to the margins suggesting that colonization from margin strips may counteract positive regulatory effects of natural enemies. Positive effects of strip margin vegetation on regulation of apple pests require a movement of natural enemies into the orchard. We tested the movements of generalist predators by labelling margin strips with egg protein and we checked whether they fed on pest insects using specific genetic marker of the codling moth (Cydia pomonella) (chapter IV). The results showed that few individuals were moving from the field margins into the orchard. However, 25% of the captured predators fed on C. pomonella still indicating a high level of natural regulation. In conclusion, the limited movement of predators from margin strips into orchards may explain the absence of differences between strip treatments in orchard pest regulation (aphids). Natural and semi-natural habitats can contribute to pest control at the margins of crops, but in apple orchards this effect strongly decreased with distance.
Rethwisch, Michael D., and Michael Kruse. "Effect of Late Winter 1998 Furadan4F Alfalfa Stubble Treatment on Alfalfa Growth and Alfalfa Weevil, Aphid, and Threecornered Alfalfa Hopper Populations." College of Agriculture, University of Arizona (Tucson, AZ), 1999. http://hdl.handle.net/10150/205153.
Full textVatka, E. (Emma). "Boreal populations facing climatic and habitat changes." Doctoral thesis, Oulun yliopisto, 2014. http://urn.fi/urn:isbn:9789526203607.
Full textTiivistelmä Ihmisen aiheuttama habitaattien katoaminen ja huononeminen sekä ilmastonmuutos vaikuttavat populaatioihin kaikkialla maailmassa. Ilmaston lämpeneminen on muuttanut monien lajien fenologioita eri trofiatasoilla. Osalla saalistajalajien populaatioista suurin ravinnontarve ei enää ajoitu samaan aikaan saaliin runsaushuipun kanssa. Ajoituksen eriaikaisuus -hypoteesin mukaan todennäköisyys populaatioon rekrytoitumiselle riippuu synkronian asteesta saaliin kanssa. Ilmaston lämpenemisen vaikutuksissa lajeihin ja populaatioihin on kuitenkin vaihtelua. Ihmisen maankäyttö muuttaa ja tuhoaa lukuisien lajien elinympäristöjä. Esimerkiksi useiden boreaalisten metsien lintupopulaatioiden pienentymistä on selitetty intensiivisellä metsätaloudella. Lahopuun määrä metsissä on vähentynyt, mikä on uhka lahopuusta riippuvaisille lajeille. Korkealaatuisten habitaattien keskeisten piirteiden tunnistaminen on tärkeää luonnonsuojelun ja kestävän metsätalouden suunnittelulle. Koska yksilöiden oletetaan valitsevan niiden kelpoisuutta maksimoivia elinympäristöjä, pesäpaikanvalinta-analyysiä voidaan käyttää tärkeiden habitaattipiirteiden tunnistamiseen. Tarkastelen väitöskirjassani ilmastonmuutoksen ja habitaattien laadun vaikutuksia boreaalisiin populaatioihin. Mallilajeina käytän koloissa pesiviä varpuslintuja. Hyödyntämällä pitkäaikaisaineistoja osoitan, että lisääntymisen ajoittuminen on aikaistunut tali- ja hömötiaisella, mutta ei sinitiaisella. Myös ravintohuippu on aikaistunut, mikä on parantanut synkroniaa hömötiaisen ja sen pääasiallisen ravinnon eli toukkien välillä. Tali- ja sinitiaisella synkronia on pysynyt hyvänä. Hyvän synkronian myönteinen vaikutus lisääntymismenestykseen vaikuttaa kuitenkin ehdolliselta: se tulee esiin vain tietyissä olosuhteissa, kuten vuosina jolloin toukkia on runsaasti. Kevään lämpötilat näyttävät vaikuttavan pesinnän ajoittumiseen erityisesti proksimaattisena tekijänä. Pesäpaikkoina toimivien seisovien lahopuiden määrä on tärkein hömötiaisen pesäpaikanvalintaa määräävä tekijä. Kaukokartoitusaineisto yksinään ei riitä luotettavien mallien tuottamiseen, sillä ekologisesti tärkeät pienen skaalan tekijät voidaan kartoittaa vain suorin maastomittauksin. Metsien harventamatta jättäminen valituilla laikuilla turvaisi lahopuun jatkuvan saatavuuden, mikä vaikuttaisi myönteisesti talousmetsien biodiversiteettiin
Costa, Suzana Regina Silveira [UNESP]. "Caracterização molecular de populações do inseto praga psilídeo de concha (Glycaspis brimblecombei) por meio de marcadores do tipo ITS 1 (Internal Tanscribed Spacer 1)." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/92450.
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O gênero Eucalyptus é originário da Austrália e está estabelecido no Brasil há mais de um século. Atualmente, o Brasil tem a segunda maior área plantada, formando monoculturas, que favorecem o estabelecimento de insetos praga. No ano de 2003 foi verificada pela primeira vez no país a ocorrência de Glycaspis brimblecombei, espécie descrita por Moore (Hemiptera, Psyllidae). Tal espécie também é conhecida por psilídeo de concha, em plantios de Eucalyptus sp. no estado de São Paulo. Devido sua alta capacidade adaptativa, atualmente se encontra amplamente distribuído por todo território nacional. Os danos causados por sua infestação são inúmeros, resultando em perdas consideráveis para o setor florestal e consequentemente para a economia brasileira. As populações do psilídeo de concha apresentam baixa variação morfológica, dificultando sua identificação; assim, análises moleculares, tais quais o uso de marcadores, podem auxiliar a responder essas questões. Um marcador amplamente utilizado, por sua alta variabilidade, é o espaçador interno transcrito do DNA ribossomal (ITS). Deste modo, o marcador ITS foi utilizado neste trabalho para averiguar a dinâmica populacional do psilídeo de concha de quatro regiões do estado de São Paulo. A sequência do ITS1 apresentou um intervalo de 291 pb em 88,73% das amostras. Os sítios polimórficos foram identificados no intervalo de 80 a 200 pb, sendo que na população de Pedra Bela foi observada a maior distribuição destes. Além disso, observou-se a ocorrência de seis haplótipos distribuídos nas quatro populações. O haplótipo 1 esteve presente em todas as populações, enquanto que o haplótipo 6 foi somente identificado na população de Criação de Laboratório. A diversidade nucleotídica (Pi) das populações foi de 0,00445, sendo que a de Criação de Laboratório...
Eucalyptus genus is derived from Australia and is settled in Brazil for more than a century now. Currently, Brazil has the second largest planted area, forming monocultures that smooth infestation with pest-insects. In 2003, the occurrence of Glycaspis brimblecombei, species described by Moore (Hemiptera, Psyllidae), was detected in Brazil for the first time. The said species is also known as red gum lerp, in Eucalyptus sp plantations in the State of São Paulo. Because of their high capacity of adaptation, nowadays they are found widely distributed all over the domestic territory. Damages caused by their infestation are numerous, resulting in considerable losses for the forestry sector and, consequently, for the Brazilian economy. Red gum lerp populations present a low rate of morphological variation, which makes their identifiction more difficult. Accordingly, molecular tests, such as the use of markers, may help answering such questions. A widely used marker, due to its high variability, is the internal transcribed spacer of ribosomal DNA (ITS). Thus, the ITS marker was used in this paper to investigate the population dynamics of red gum lerps from four regions in the State of São Paulo. ITS1 sequence showed a range of 291 bp in 88.73% of the samples. Polymorphic sites were identified in the range of 80-200 bp, with the population from Pedra Bela showing the highest distribution. Moreover, the occurrence of six haplotypes distributed in the four populations was found. Haplotype 1 was present in all populations, while haplotype 6 was identified in lab-developed population only. The nucleotide diversity (Pi) of populations was 0.00445, while the lab-developed population showed the highest Pi value as between the four populations. In Botucatu, no diversity was found. Specific oligonucleotides flanking the polymorphic regions of the... (Complete abstract click electronic access below)