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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Efeito do ensacamento na qualidade do fruto do tomate sob manejo org?nico e convencional / Efects of baggins on the quality of tomato fruits under organic and conventional management

Ferreira, Margarete Satsumi Tiba 30 July 2013 (has links)
Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-02-21T13:17:10Z No. of bitstreams: 1 2013 - Margarete Satsumi Tiba Ferreira.pdf: 3840889 bytes, checksum: abf630228fe1ec8e263f83e62d380174 (MD5) / Made available in DSpace on 2017-02-21T13:17:10Z (GMT). No. of bitstreams: 1 2013 - Margarete Satsumi Tiba Ferreira.pdf: 3840889 bytes, checksum: abf630228fe1ec8e263f83e62d380174 (MD5) Previous issue date: 2013-07-30 / Two experiments were conducted on two farms located in the city of Nova Friburgo - RJ, Cultivar and Hikari. On Cultivar farm, tomato was cultivated under organic management in a 4 x 2 factorial design experiment - with four types of bagging and two types of ground coverages - in four replications. Besides the referential treatment, which was conducted bagless, brown paper, nonwoven fabric and glassyne were tested over the period of August to December 2012. The tomato was grown under straw black oats and lupins. On Hikari farm, which was in an agroecological transition, we performed the second experiment, conducted in two different greenhouses, one under chemical management and other under biological management, both performed over the period of October 2012 to March 2013. The experiment was conducted in a 2 x 2 completely randomized experimental design (glassyne paper, without bagging and with both types of pest control, chemist and biological) with eight repetitions. In both experiments Tomatec principles were adopted using mulching, drip irrigation, vertically trellised staking, organic fertilization and integrated pest management (IPM). The evaluated parameters were bagging fresh weight influence, diameter, amount of residues and fruit production. The farmers and the student?s approach over tomato production with agroecological transition bias allowed us to understand the sustainable production challenges on protected areas and provided a great experience on procedures, empowerment and professional knowledge. Bagging increased tomato yield under organic production, and the brown paper bags made the most of outstanding quality and production. Compared to the bagless process, economic gains were present in treatments with biological and chemical management using glassyne. / Foram realizados dois experimentos em duas propriedades rurais, S?tio Cultivar e S?tio Hikari, localizados no munic?pio de Nova Friburgo-RJ. No S?tio Cultivar o tomate foi cultivado sob manejo org?nico num experimento em delineamento experimental com blocos inteiramente casualizados em fatorial 4 x 2 (quatro tipos de ensacamentos e dois tipos de cobertura do solo) com quatro repeti??es. Al?m do tratamento referencial, que foi o sem o uso do saco, foram testados o papel pardo, o tecido n?o tecido (TNT) e o papel glassyne no per?odo de agosto a dezembro de 2012. O tomate foi cultivado sob as palhadas de aveia preta (Avena strigosa ) e tremo?o branco (Lupinus albus). No S?tio Hikari em transi??o agroecol?gica, o tomate foi cultivado em duas estufas, uma sob manejo qu?mico e a outra com manejo biol?gico no per?odo de outubro de 2012 a mar?o de 2013. Este estudo foi realizado no delineamento experimental de blocos inteiramente casualizados com quatro tratamentos em fatorial 2 x 2 (papel glassyne e sem ensacamento e dois tipos de controle fitossanit?rio, um qu?mico e outro biol?gico), com oito repeti??es. Em ambos os experimentos foram adotados os princ?pios do sistema de produ??o denominado de Tomatec, utilizando-se cobertura vegetal, irriga??o com gotejamento, tutoramento vertical com fitilho, aduba??o org?nica/mineral e o manejo integrado de pragas (MIP). Os par?metros avaliados foram a influ?ncia do ensacamento no peso fresco, di?metro, quantidade de res?duos e na produ??o dos frutos. Abordagem sobre a viv?ncia dos produtores e da mestranda sobre a produ??o de tomate com vi?is de transi??o agroecol?gica permitiu compreender os desafios da produ??o sustent?veis dos ambientes protegidos e uma grande experi?ncia em torno dos processos de produ??o, empoderamento e conhecimento profissional. O ensacamento aumentou a produtividade do tomateiro em sistema org?nico de produ??o, sendo os sacos confeccionados com papel pardo os que mais se destacaram na qualidade e na produ??o. Nos tratamentos com manejo qu?mico e biol?gico, houve um ganho econ?mico com a utiliza??o do papel glassyne, comparativamente ? aus?ncia de ensacamento
42

Dinâmica populacional de Cosmopolites sordidus (Coleoptera: Curculionidae) em bananal, cv. nanicão, em São Miguel do Iguaçu, Pr, e sua susceptibilidade a isolado de Beauveria bassiana / Population dynamic of Cosmopolites sordidus (Coleoptera: curculionidae) in banana plant, cv. nanicão in São Miguel do Iguaçu, Paraná, Brazil, and its susceptibliy to isolate Beauveria bassiana

Prestes, Tânia Mari Vicentini 26 January 2005 (has links)
Made available in DSpace on 2017-07-10T17:37:34Z (GMT). No. of bitstreams: 1 Tania_M_V_Prestes.pdf: 506597 bytes, checksum: 9d5adad3528afe89c92f3c3cfc7bc17a (MD5) Previous issue date: 2005-01-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Cosmopolites Sordidus (Germar, 1824) is considered a pest of economic importance in almost all banana producer countries. Knowing the highest incidence season of the pest, and the occurrence of its natural enemies, mainly entomopathogenic fungus, associated or not to environment factors, makes the development of strategies control that cause little impact on the environment possible. With this in mind, the study of C. sodidus population dynamic in banana plant cultivation of the nanicão cultivar without the use of insecticides was carried in the city of São Miguel do Iguaçu, Paraná, Brazil. A biological experiment with Beauveria bassiana (Bals.) Vuill, originated from the experimental area and from Brazil s Research Centers, was conducted aiming to evaluate C. sordidus pathogenicity. The insect s population fluctuation was evaluated between June 2003 to May 2004 using pseudostem traps. Pseudostem traps durability and attractiveness were observed as well as the occurrence of the entomopathogenic fungus, and the presence of predators. Obtained data was correlated to environmental factors observed during the evaluations. It was observed that C. sordidus population fluctuation was negatively influenced by rain precipitation. Adult population summit occurred in June and July 2003, period of cool temperature and low rain precipitation. C. sordidus larvae summit occurred in December when temperature (29.7ºC) and rain precipitation (308.6 mm) were the highest. Predators were identified as pertaining to following order and family correspondingly: Coleoptera (Carabidae), Dermaptera (Forficulidae), Hemiptera (Reduviidae), Hymenoptera (Ponerinae) and Aranae (Ctenidae, Clubionidae, Lycosidae) which usually feed from C. sordidus eggs and larvae. Predator population summit occurred two months following C. sordidus adult population summit. Although at low incidence, with an annual average of 0.44%, adults infected by B. bassiana were found, where the highest infection indexes occurred in September and October (1.2%). In laboratory conditions all of the B. bassiana isolates caused C. sordidus adult mortality, and there weren t significant statistical differences among them, indicating that they can be utilized for the controlling of pest / Cosmopolites sordidus (Germar, 1824) é considerado uma praga de importância econômica em quase todos os países produtores de banana. Conhecer a época da maior incidência desta praga, ocorrência de seus inimigos naturais, principalmente fungos entomopatogênicos, em associação aos fatores ambientais, possibilitam o desenvolvimento de estratégias de controle que causem menos impacto sobre o ambiente. Nesse contexto, foi realizado em São Miguel do Iguaçu, PR, o estudo da dinâmica populacional de C. sordidus, em cultivo de bananeira da cultivar nanicão, isento do uso de inseticidas. Realizou-se também, um bioensaio com isolados de Beauveria bassiana (Bals.) Vuill. provenientes da área experimental e de Centros de Pesquisa do Brasil, com o objetivo de avaliar a patogenicidade para C. sordidus. A flutuação populacional do inseto foi avaliada com utilização de iscas do tipo telha, durante um ano no período de junho de 2003 a maio de 2004. Acompanhou-se a durabilidade e atratividade das iscas, bem como a ocorrência de fungos entomopatogênicos e também a presença de predadores. Os dados obtidos foram correlacionados aos fatores ambientais observados durante o transcorrer das avaliações. Verificou-se que a flutuação da população de adultos de C. sordidus foi influenciada negativamente pela precipitação, sendo que os picos populacionais dos adultos ocorreram em junho e julho de 2003, período de temperaturas amenas e baixas precipitações. O pico das larvas de C. sordidus ocorreu em dezembro período no qual, a temperatura e as precipitações pluviométricas foram as mais elevadas (29,7ºC) e (308,6mm). Os predadores foram identificados como pertencentes às ordens e famílias, respectivas: Coleoptera (Carabidae), Dermaptera (Forficulidae), Hemiptera (Reduviidae), Hymenoptera (Ponerinae) e Aranae (Ctenidae, Clubionidae, Lycosidae). O pico da população de predadores ocorreu dois meses após o pico da população de adultos de C. sordidus. Foram verificados adultos infectados por B. bassiana, porém em baixa incidência (média anual de 0,44%), com maiores índices de infecção em setembro e outubro (1,2%). Em condições de laboratório, os isolados de B. bassiana causaram mortalidade dos adultos de C. sordidus, não havendo diferenças significativas estatisticamente entre eles (cerca de 20% de mortalidade), indicando que os mesmos podem ser utilizados para o controle da praga
43

IMPACT OF SELECTED INTEGRATED PEST MANAGEMENT TECHNIQUES ON ARTHROPODS IN CUCURBIT PRODUCTION SYSTEMS

Skidmore, Amanda R. 01 January 2018 (has links)
Cucurbits (i.e. squash, melons, pumpkins, gourds) are high value crops of global importance. Insect pests in these systems are often controlled by chemical insecticides, which are not always effective and can be damaging to the environment. Many integrated pest management (IPM) techniques have been developed for the control of pests in these systems, with a goal of improving system stability and reducing chemical inputs. The overarching goal of my research was to investigate the impact of select IPM techniques on arthropod populations and yield in organic and conventional cucurbit systems. This dissertation can be divided into three major projects which were conducted between 2013 and 2017. First, an investigation was conducted to understand the impact of two commonly used IPM practices (tillage regime and the use of row covers) on pest insect populations, beneficial arthropod populations, and plant yield. By developing studies in both organic and conventionally managed squash and melon production, four independent studies were conducted and analyzed to provide a broad understanding of these IPM strategies. In all systems, plant yields and pests were greatest in the plasticulture systems, but reduced tillage had a positive impact on the natural enemy arthropods within these crops. Row cover use resulted in larger plants and increased yields, but had an inconsistent influence on arthropods in the systems studied. From these initial studies, an additional investigation was developed to better understand the impacts of cultivation on the specialist pollinator Peponapis pruinosa [Hymenoptera: Apidae]. Nesting site selection was examined in two independent experiments. By conducting choice studies to allow P. pruinosa to select preferred nesting sites, we determined that P. pruinosa prefer to build nests in loose soils and show reduced nest making in compact soils. This poses interesting management challenges since less-compact soils are within high tillage zones. This research supports the need for the development of cultivation management plans that consider of pollinator habitat and reproduction needs. A multi-year, multi-farm study was developed for the comparison of parasitism in cucumber beetles (Acalymma vittatum and Diabrotica undecimpunctata) in organic and conventional growing systems. Parasitoids were reared from beetles collected from working organic and conventional cucurbit farms in central Kentucky. Our results show that there is some seasonal variation in parasitism, but that there is no significant difference between organic and conventional production. We conclude that IPM techniques can be effective in contributing to the control cucurbit pests in agroecosystems and the improvement of crop yields. These studies show that natural enemies and pollinators react differently to IPM practices, which should be considered when developing IPM plans in cucurbit production. By researching these management techniques we are able to develop production systems that have increased stability.
44

Integrated Management of Billbugs (Coleoptera: Dryophthoridae) in Intermountain West Turfgrass

Dupuy, Madeleine M. 01 August 2018 (has links)
Billbugs are a serious pest of turfgrass in the Intermountain West. Billbug larvae severely discolor and eventually kill turfgrass by feeding in stems, on roots, and on crowns of the plant. Billbugs are typically managed with preventive, calendar-based applications of insecticides. Most of our knowledge on the biology and management of billbugs comes from research in the eastern U.S, and little is known about billbug biology and best management practices in the Intermountain West. First, I examined the seasonal activity of billbug life stages in Intermountain West turfgrass and developed a predictive degree-day model to better time management strategies against billbugs. I found that compared to the eastern U.S., a regional model that starts earlier (January 13) and has a cooler insect development threshold (3oC) was adequately robust to predict billbugs in Utah and Idaho. Next, I used the Utah-Idaho degree-day model to determine whether preventive and curative timings for billbug management developed in the eastern U.S. were effective in the Intermountain West. Testing four insecticides with the Utah-Idaho model and with eastern U.S. management timings I found that there was support to consider adoption of these same recommendations in Utah and Idaho, particularly for current preventive insecticides such as neonicotinoids and anthranilic diamides. Finally, considering that turf insecticides can negatively impact predatory insects, thought to viisuppress turf pests, I assessed the predatory arthropod community in Intermountain West turf and their impacts on billbugs. I found that the predatory arthropod community consisted primarily of ground beetles and spiders, representing 60% and 28% of all predators, respectively. I found that predators contributed the most by consuming billbug eggs and by changing the behavior of billbug adults with an observed reduction in mating activity. My research not only lays the ground work for development of effective, sustainable integrated management of billbugs in Intermountain West turfgrass, including conservation biocontrol,but also illustrates the necessity of regional predictive models, monitoring, and appropriate timing of management for successful turf pest suppression.
45

Variability in abundance of the rosy apple aphid (Dysaphis plantaginea), the role of its alternate host (Plantago major), and potential control strategies in organic apple orchards in British Columbia

Brown, Amanda Erica 05 1900 (has links)
The rosy apple aphid, Dysaphis plantaginea, (Homoptera: Aphididae) is a serious pest of apples in British Columbia (BC), Canada and especially in organic orchards where conventional controls cannot be used. The goals of this study were to determine the environmental or management factors of an orchard that lead to high aphid populations, to conduct an economic assessment of the damage, to determine the timing of autumn migration, and to test several autumn and spring chemical control methods and two novel autumn mechanical control methods targeting the aphids while on their alternate host, Plantago major. To explain the variation among orchards, I evaluated several potential correlates of aphid density: abundance of the alternate host (plantain, Plantago major), foliar tree nitrogen, tree age, tree planting density, and the application of an oil treatment in spring. Stepwise regression indicated that foliar nitrogen and tree age explain 27% of the variation. Orchards receiving a spring oil application had a 53% lower average aphid infestation level. Plantain abundance was not related to aphid population on apple. However, experimental manipulation of leaf angle from the ground and size showed that significantly more alate and apterous aphids occurred on large, low angle leaves. Mowing prior to spring aphid migration was associated with 75% fewer alatae and apterae on the plantain. The loss in harvest resulting from aphid damage ranged from 3% to 76% of the crop. Effective autumn control depends on accurate timing of aphid flight. The peak of female flight occurred on the 27th of September, 2007 at 11:56 hours daylength (sunrise to sunset) and the peak of male flight occurred on the12th of October, 2007 at 11:02 hours daylength. Aphid densities in the spring of 2008 were very low, making comparisons between treatments and controls difficult. Autumn applications of Superior dormant oil and kaolin clay were not effective. The PureSpray Green treatments of two October applications and one April application showed a significant reduction in rosy apple aphid infested clusters compared with the untreated control. Mowing and rotavating did not result in a significant reduction in aphid infestation level.
46

Variability in abundance of the rosy apple aphid (Dysaphis plantaginea), the role of its alternate host (Plantago major), and potential control strategies in organic apple orchards in British Columbia

Brown, Amanda Erica 05 1900 (has links)
The rosy apple aphid, Dysaphis plantaginea, (Homoptera: Aphididae) is a serious pest of apples in British Columbia (BC), Canada and especially in organic orchards where conventional controls cannot be used. The goals of this study were to determine the environmental or management factors of an orchard that lead to high aphid populations, to conduct an economic assessment of the damage, to determine the timing of autumn migration, and to test several autumn and spring chemical control methods and two novel autumn mechanical control methods targeting the aphids while on their alternate host, Plantago major. To explain the variation among orchards, I evaluated several potential correlates of aphid density: abundance of the alternate host (plantain, Plantago major), foliar tree nitrogen, tree age, tree planting density, and the application of an oil treatment in spring. Stepwise regression indicated that foliar nitrogen and tree age explain 27% of the variation. Orchards receiving a spring oil application had a 53% lower average aphid infestation level. Plantain abundance was not related to aphid population on apple. However, experimental manipulation of leaf angle from the ground and size showed that significantly more alate and apterous aphids occurred on large, low angle leaves. Mowing prior to spring aphid migration was associated with 75% fewer alatae and apterae on the plantain. The loss in harvest resulting from aphid damage ranged from 3% to 76% of the crop. Effective autumn control depends on accurate timing of aphid flight. The peak of female flight occurred on the 27th of September, 2007 at 11:56 hours daylength (sunrise to sunset) and the peak of male flight occurred on the12th of October, 2007 at 11:02 hours daylength. Aphid densities in the spring of 2008 were very low, making comparisons between treatments and controls difficult. Autumn applications of Superior dormant oil and kaolin clay were not effective. The PureSpray Green treatments of two October applications and one April application showed a significant reduction in rosy apple aphid infested clusters compared with the untreated control. Mowing and rotavating did not result in a significant reduction in aphid infestation level.
47

Integrated pest management of Sitona lineatus L. (Coleoptera: Curculionidae) in crops of Pisum sativum L. (Fabales: Fabaceae) in Western Canada

Vankosky, Meghan Ann Unknown Date
No description available.
48

Integrating the building blocks of agronomy into an integrated pest management system for wheat stem sawfly

Beres, Brian Unknown Date
No description available.
49

New options for Integrated Pest Management of Varroa destructor (Acari: Varroidae) in colonies of Apis mellifera (Hymenoptera: Apidae) under Canadian Prairie conditions

Vandervalk, Lynae P Unknown Date
No description available.
50

Integrated pest management of Sitona lineatus L. (Coleoptera: Curculionidae) in crops of Pisum sativum L. (Fabales: Fabaceae) in Western Canada

Vankosky, Meghan Ann 11 1900 (has links)
Sitona lineatus L. (Coleoptera: Curculionidae) is a pest of Pisum sativum L. (Fabales: Fabaceae) and managing it is a challenge because of its fecundity, migratory behavior and concealed larval habitat. Potential components of an integrated pest management program for S. lineatus were investigated near Lethbridge and Vauxhall, Alberta over three years. Cage studies indicated that larval feeding is more damaging than adult feeding but that larval populations are not dependent on adult weevil density. In open plot experiments, thiamethoxam-treated plants experienced significantly less foliar feeding damage than plants receiving no insecticide treatment but no consistent effects on yield were observed for any plot treatment over six site-years. Rhizobium inoculation had a synergistic interaction with thiamethoxam. Laboratory trials showed that Bembidion quadrimaculatum L. (Coleoptera: Carabidae) consumed S. lineatus eggs. Seed treatment with thiamethoxam and Rhizobium inoculant, and egg predation should be included in an integrated pest management program for S. lineatus. / Plant Science

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