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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.
21

Investigation of the Biocontrol Activity in vitro and in planta of Different Pseudomonas Species Against Important Crown, Stem, Foliar and Root Pathogens of Ornamental Crops

Martin, Dana January 2017 (has links)
No description available.
22

Understanding Japanese Maple Scale Biology to Inform Sustainable Pest Management Practices in Virginia Nurseries

Wyatt, Mollie McDonnell 04 June 2024 (has links)
Lopholeucaspis japonica (Cockerell) (Hemiptera: Diaspididae), commonly known as Japanese maple scale (JMS), is an invasive pest established in the United States in 1914. Over the past decade, JMS infestations have escalated, posing a significant threat to the nursery industry, and resulting in economic losses from unsellable infested plants. The limited understanding of JMS hampers the development of effective management strategies, intensifying the financial impact of this destructive pest. To contribute to the development of a sustainable pest management program, it is crucial to acquire knowledge of JMS's natural history, biology, and dispersal capabilities. Management costs can be reduced by determining the optimal timing for scouting and spraying through peak crawler emergence and the identification of overwintering life stages. Understanding JMS dispersal patterns within tree canopies can lead to the refinement of scouting methods, such as strategically placing the tape method (for monitoring crawlers). A two-year study took place at two separate locations and on boxwoods (2022-2023) and red maples (2023). Our phenology findings indicated that there were two generations and prolonged crawler presence which can extend over a period of 34 weeks (March-October) during the growing season. The first generation of crawler emergence on boxwoods started as early as the second week of March [110-114 Growing Degree Days in base 50°F (GDD50)], with the first peak occurring in mid-June [1179-1514 GDD50]. The second generation depending on the year began in July and peaked between early September and mid-August due to overlapping from prolonged presence of crawlers. Crawler emergence on maples indicated the first peak during the second week of July, followed by the second peak during the third week of August. Management practices, including monitoring and chemical control and based on phenology data, could be suggested to begin early March and continue throughout the season putting high pressure on crawlers during the peaks of activity. Overwintering studies from this project suggested JMS could be developing throughout winter with immatures found in January and February while in March the highest population was adults. Using horticultural oil during the winter months may help with JMS infestations. To investigate dispersal patterns, the canopy of experimental plants of maples and boxwoods were divided into top, middle, and bottom sections based on plant height. Comparative analysis of JMS crawler densities within the canopies of maples indicated that the middle canopy sections exhibited higher crawler densities compared to the top sections. However, when evaluating all three sections (top, middle, and bottom), the bottom sections displayed the highest crawler densities. Examination of cardinal points within the top and middle canopies of maples revealed a widespread distribution pattern. In contrast, no significant differences in crawler densities were observed between the various canopy sections of boxwoods, indicating a uniform distribution across the plant. / Master of Science in Life Sciences / Japanese maple scale (JMS), scientifically known as Lopholeucaspis japonica, is an invasive pest damaging ornamental plants in the United States since 1914, particularly affecting the nursery industry in the Southeast, including Virginia. This study aimed to enhance the understanding of JMS phenology, overwintering biology, and dispersal patterns. A two-year study took place at two separate locations and on boxwoods (2022-2023) and maples (2023). Phenology and dispersal patterns were monitored using the tape method to count crawlers per cm². Over two years, 100 JMS specimens were inspected monthly for three consecutive winter months to record overwintering life stages. Across both years and crops there were two peaks of activity with the first peak being between June and July and the second falling in between August and September. For overwintering, higher numbers of JMS immatures were found in January and February, and adults in March. To investigate dispersal patterns, the canopy of experimental plants of maples and boxwoods were divided into top, middle, and bottom sections based on plant height. Comparing JMS crawler densities in maples between the top and middle canopy sections revealed higher densities in the middle. However, when all three sections in maples were compared, the bottom had the highest density of crawlers. Cardinal points within the top and middle canopies were investigated for maples only and showed a widespread distribution when examining those points. For boxwoods, no significant difference was found in crawler densities between plant sections. This knowledge will empower nursery growers to make informed decisions, optimize their efforts in monitoring and control, and minimize the economic impact caused by JMS infestations.
23

Understanding Red Headed Flea Beetle Biology to Inform Sustainable Pest Management Practices in Virginia Nurseries

Lane, Eleanor Lynn 16 February 2023 (has links)
Systena frontalis (F.) (Coleoptera: Chrysomelidae), the red headed flea beetle (RHFB), is a ubiquitous pest of ornamental nursery crops in the eastern United States. Defoliation by adults renders plants unsaleable. Control costs and economic losses from injured plants have become a top concern among Virginia nurseries in the past decade. Current management tactics include spraying insecticides up to three times a week during the adult active season. The frequent use of insecticides poses a risk to the environment, non-target organisms, and evolution of resistance within the targeted beetle population. To develop a sustainable pest management program, more information is needed to understand pest biology, quantify the injury potential, and explore control tactics. Methods to monitor this beetle were used to observe peak activity throughout the growing season as well as the adult daily activity levels. There were three observed generations with population peaks in late June, late July, and late August into early September. Within the scale of one day, adult beetles were found to be diurnal with peaks in activity in the middle of the day. These findings will inform growers of the most efficient times to scout and spray, ultimately reducing insecticide usage. Quantification of feeding damage to individual leaves, the entire plant, and preference between older and newer growth may relate plant injury with specific population densities. The use of phenyl ethyl alcohol as an attractant lure, was explored to bolster pest control. Finally, insecticide bioassays were performed to compare those currently used to others yet untested. / Master of Science in Life Sciences / The red headed flea beetle (RHFB) is an important pest of ornamental crops in open-field nurseries along the Eastern United States. Defoliation caused by adult feeding renders plants unsellable. Japanese hollies, hydrangeas, and sweetspire iteas are among the most affected plants. Infested nurseries suffer severe economic losses due to insecticide costs and plant inventory reductions. Growers are spraying insecticides up to three times a week to manage RHFB. Frequent use of insecticides poses risks to the environment non-target organisms. This study will help improve control tactics for this pest and potentially minimize non-target effects by reducing insecticide usage. Understanding when beetles are active throughout the day, and throughout the growing season, may inform timing of scouting and insecticide sprays to maximize effectiveness. With populations highest in late June, late July, and late August, RHFB is estimated to have three generations per year. Adults are most active in the middle of the day and sedentary at night. It was observed how different densities of beetles cause injury to individual leaves and entire plants, and compared feeding preference on older versus newer growth. Chemical control tactics were explored including insecticides labeled and not labeled for RHFB such as iscycloseram. Finally, the effectiveness of phenyl ethyl alcohol as an attractant lure for RHFB was assessed and found ineffective within the open-field nursery ecosystem.
24

Overcoming Summer Dormancy of Boxwood

Musselwhite, Sheri Ruth 29 April 2002 (has links)
The objective of this work was to determine if summer dormancy of boxwood could be removed either through nutritional or hormonal means. Buxus sempervirens L. "Suffruticosa", B. sempervirens "Vardar Valley", and B sinica var. insularis (Nakai) "Justin Brouwers" were used for these studies. In the nutrition study, experiments were conducted to examine the effects of various levels of Osmocote 15-9-12 and liquid 10-4-6 on growth of boxwood. Optimal shoot dry weight was achieved at applications of 12 to 16 g Osmocote and 100 – 150 ppm N liquid fertilizer. Leachate EC corresponding to optimal shoot dry weight ranged from 0.5 to 0.7 dS/m for Osmocote and from 0.7 to 1.5 dS/m for liquid fertilizer. While the fertilizer requirements for boxwood optimal dry weight accumulation were determined, additional flushes of growth subsequent to the initial spring flush did not occur for "Vardar Valley" and English boxwood. In the phytohormone study, experiments were conducted that examined the effects of pruning, Promalin (GA4+7 and BA), and defoliation on the growth of three boxwood species. While Promalin applied alone or in conjunction with pruning shows promise of increasing new shoot growth, its response was not consistent from experiment to experiment. In fact, when it was applied in conjunction with defoliation, it dramatically decreased number of new shoots and actually resulted in some shoot mortality. Pruning was also erratic in its promotion of new shoots. Defoliation increased new shoot number dramatically and shows the most promise in overcoming summer dormancy. / Master of Science
25

Diversidade genética e estudo de geração em características morfoagronômicas de pimenteiras ornamentais (Capsicum annuum) / Genetic diversity and generation study on morphologic and horticultural traits of ornamental pepper (Capsicum annuum)

Nascimento, Mayana Ferreira 26 February 2014 (has links)
Made available in DSpace on 2015-03-26T13:42:32Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1110657 bytes, checksum: a43067f6b09dd224c98d49e2ccdf4f2f (MD5) Previous issue date: 2014-02-26 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The Capsicum peppers are grown in a wide variety of types, sizes, colors, flavors and pungencies for various purposes. In addition, more recently, the great diversity of Capsicum has fostered its trade as ornamental plants, but there are few commercial varieties for ornamental purposes. The knowledge about the inheritance of the traits that will be submitted to continuous selections and the diversity generated from crosses are very important for the success of a breeding program of ornamental pepper. This study aimed to analyze the genetic diversity and a generation study in ornamental pepper. The genetic diversity were studied in a family structured in six generations, based on quantitative and qualitative data, separately and integrated in the same analysis. The generations study was done on quantitative traits, identifying the allelic interactions involved in the genetic control of traits. There were estimated the additive, dominance, phenotypic, genetic and environmental variance, the heritability in broad and narrow sense and genetic effects additive, dominant and epistatic (additive x additive, additive x dominance and dominance x dominance). The studies are part of the Capsicum breeding program of Federal University of Paraíba (UFPB) and Federal University of Viçosa (UFV). Two accessions of ornamental pepper plants belonging to the germplasm bank of vegetables UFPB (01, 132) were chosen based on earlier diallel study. Plants of the accessions 01 and 132 were crossed to generate the hybrids (F 1 ). The F1's hybrids were backcrossed to the parental‟s to generate the backcross progenies (BC 1 and BC 2 ) and self pollinated to generate the F 2 generation. There were studied 10 plants of each parent and F 1 , 72 plants of backcross 1 (BC 1 ), 75 plants of backcross 2 ( BC 2 ) and 147 plants of the segregating F 2 generation. All generations were applied for the analysis of genetic diversity. First a matrix was generated about the 22 quantitative characters according to the clustering method of Tocher, and then another matrix with only 19 multicategoric characters based on the arithmetic complement of the index of coincidence simple. The data integration was performed by the sum of the two matrices. The data of all generations were used to study the variances, means and allelic interactions of the 22 quantitative traits evaluated. The crosses between the parents and 01 132 generated variability in the segregating generations (F 2 ) and backcrosses (BC 1 and BC 2 ) according the individual analyzes of quantitative multicategoric and also according the study based on data integration of different kinds of characters. The traits that more contributed to genetic divergence were number of seeds per fruit, number of fruits per plant, days to flowering and days to fruiting, discarding the other variables. The following individuals are liable to selection: 5 of generation F1; 1, 35, 37, 39, 43, 44, 47 and 49 of the segregating F 2 generation in order to obtain higher number of seeds per fruit. The individuals 2, 7, 8, 16, 17, 20, 23, 27 and 44, of the generation F 2 can be selected aiming higher number of fruits per plant. The individuals 28 of F 2, the plants 18, 20, 21 and 22 of BC 1 and 1, 5, 14 and 16 of the BC 2 (F 1 x 132) are useful for the selection for early flowering and early fruit set. The additive part of the phenotypic variance found for plant height, diameter of the petal, anther length, number of fruits per plant and days to flowering and to fruiting lead to the conclusion that the phenotypic selection in the F 2 generation should be efficient to obtain genetic gains. According to the reduced model, the traits crown diameter, fruit diameter and number of seeds per fruit were not influenced by epistatic effects, but only the additive and dominant, what make possible to select superior individuals in segregating generations or improve these traits by means of hybridization, respectively. / As pimentas do gênero Capsicum são cultivadas em uma imensa variedade de tipos, tamanhos, cores, sabores e pungências para diversos fins. Mais recentemente, a grande diversidade existente no gênero Capsicum tem fomentado o comércio de pimenteiras como plantas ornamentais, porém há poucas variedades comerciais para ornamentação. O conhecimento do tipo de herança envolvida no controle das características que irão passar por contínuas seleções e a diversidade gerada a partir dos cruzamentos são de suma importância para o sucesso de um programa de melhoramento de pimenteiras ornamentais. Os objetivos do trabalho foram analisar a diversidade genética de uma família estruturada em seis gerações, utilizando dados quantitativos e qualitativos separadamente e integrados em uma mesma análise e realizar estudo de gerações em caracteres quantitativos de pimenteiras ornamentais, identificando os tipos de interação alélica envolvida no controle genético das características, estimar as variâncias aditivas, dominância, fenotípica, genética e ambiental, as herdabilidades no sentido amplo e restrito e os efeitos genéticos aditivo, dominantes e epistáticos (aditivo x aditivo, aditivo x dominante e dominante x dominante), bem como dar continuidade ao programa de melhoramento de Capsicum da Universidade Federal da Paraíba e Universidade Federal de Viçosa. Para tanto, foram utilizados primeiramente dois acessos de pimenteiras ornamentais pertencentes ao banco de germoplasma de Hortaliças da UFPB (01 e 132) com base em trabalhos anteriores de dialelo. Foram realizados cruzamentos entre os parentais (01 e 132) para gerar os híbridos (F1) e entre os F1‟s e seus parentais para gerar os retrocruzamentos (RC1 e RC2). Para obtenção das sementes da geração segregante F2 foi realizada autofecundação da geração F1. Foram utilizadas 10 plantas de cada genitor e F1, 72 plantas de Retrocruzamento 1 (RC1), 75 plantas de Retrocruzamento 2 (RC2) e 147 plantas da geração segregante F2. Para a análise de diversidade genética foram utilizadas todas as gerações, inicialmente foi gerada uma matriz apenas dos 22 caracteres quantitativos conforme o método de agrupamento de Tocher, em seguida uma outra matriz apenas com os 19 caracteres multicategóricos com base no complemento aritmético do índice de coincidência simples e para integração dos dados foi realizado a soma das duas matrizes. Todas as gerações foram utilizadas para os estudos variâncias, médias e interações alélicas para os 22 caracteres quantitativos avaliados. O cruzamento entre os genitores 01 e 132 gerou variabilidade nas gerações segregantes (F2) e nos retrocruzamentos (RC1 e RC2) quando foram realizadas análises individuais dos caracteres quantitativos, multicategóricos e quando foi feito a integração dos dados de diferente natureza. As características que mais contribuíram para divergência genética foram número de sementes por fruto, número de frutos por planta, dias para floração e dias para frutificação, descartando as demais variáveis. São passíveis de seleção os indivíduos 5 da geração F1, 1, 35, 37, 39, 43, 44, 47 e 49 da geração segregante F2 com intuito de obter maiores número de sementes por fruto. Os indivíduos 2, 7, 8, 16, 17, 20, 23, 27 e 44, da geração segregante F2 são adequados para obter maior número de frutos por planta. E os indivíduos 28 da geração F2, plantas 18, 20, 21 e 22 do Retrocruzamento 1 e as plantas 1, 5, 14 e 16 do Retrocruzamento 2 (F1 x 132) são úteis para obter plantas mais precoces em relação ao florescimento e frutificação. A parte da variância aditiva observada na variação fenotípica encontrada para as características altura da planta, diâmetro da pétala, comprimento da antera, número de frutos por planta, dias para floração e dias para frutificação levam a concluir que a seleção de indivíduos nas gerações F2 por meio da seleção fenotípica deve ser eficiente, possibilitando a obtenção de ganhos genéticos. A adequação do modelo reduzido para explicar as características diâmetro da copa, diâmetro do fruto e número de sementes por fruto, permite concluir que os efeitos epistáticos não influenciaram no controle destes caracteres, apenas os aditivos e dominantes, podendo-se selecionar indivíduos superiores em gerações segregantes ou praticar a hibridação, respectivamente.
26

Évaluation de suppléments alimentaires pour deux espèces d’acariens prédateurs, Amblyseius swirskii et Neoseiulus cucumeris (Acari: Phytoseiidae) pour l’optimisation du contrôle biologique du thrips des petits fruits (Frankliniella occidentalis) en serriculture

Faucher Delisle, Julie 01 1900 (has links)
Projet réalisé en cotutelle avec Jacques Brodeur et Les Shipp / Ce projet de recherche a examiné le supplément alimentaire comme technique pour accroître l'efficacité de deux espèces d’acariens prédateurs, Neoseiulus cucumeris et Amblyseius swirskii contre le thrips des petits fruits Frankliniella occidentalis. Des tests en laboratoire ont vérifié l’adéquation de trois espèces de pollen – de quenouille, de maïs et de pomme – ainsi que des œufs de la pyrale Méditerranéenne de la farine pour les acariens prédateurs à l'étude. En termes de valeur rm, les œufs de pyrale et les pollens de quenouille et de pomme étaient de qualité égale pour A. swirskii, tandis que le pollen de pomme s’est distingué pour N. cucumeris. Lorsque nourris d’oeufs de la pyrale, les deux espèces ont complété leur développement avec des valeurs de rm élevées. Le pollen de pomme est apparu comme étant un supplément alimentaire accessible et adéquat pour les deux prédateurs. À court terme (période de 24h), l’influence du pollen de pomme sur les interactions trophiques (larves de F. occidentalis comme proie) et intraguildes (entre les espèces de prédateurs) sur chrysanthèmes standardisés a été examinée. La présence de pollen a considérablement réduit la prédation de N. cucumeris sur les thrips ainsi que la prédation intraguilde pour les deux prédateurs. L'impact du pollen de pomme sur les populations de thrips et sur la rétention des prédateurs dans une culture de chrysanthèmes a été évalué sur une période de 4 semaines. L'introduction de A. swirskii avec pollen a permis le meilleur contrôle des populations de thrips tandis que N. cucumeris ne s’est pas établi dans la culture lorsqu'il a été introduit seul. Le pollen de pomme a amélioré la lutte au thrips par A. swirskii dans une culture de chrysanthème via une réponse numérique de la proie et la rétention des prédateurs dans la culture. Le plus bas taux de dommages importants a été observé lorsque les deux acariens prédateurs étaient utilisés de concert. / This research investigated supplemental food source as a technique to increase the efficiency of two species of predatory mites, Neoseiulus cucumeris and Amblyseius swirskii against the western flower thrips Frankliniella occidentalis. Laboratory assays aimed to assess the suitability of three pollen species – cattail, maize and apple – and eggs of the Mediterranean flour moth as supplemental food source for the predatory mites under study. In terms of rm value, flour moth eggs, cattail pollen and apple pollen were food sources of equal quality for A. swirskii, while apple pollen appeared to stand out for to N. cucumeris. Maize pollen was a less suitable food source for both species. When fed flour moth eggs, A. swirskii and N.cucumeris completed development and showed high rm values. Apple pollen appeared to be an accessible and suitable food source for both predators. Short term (24h period) influence of apple pollen availability on trophic (F. occidentalis larvae as prey) and intraguild (between the predator species) interactions on standardized chrysanthemum was examined. It significantly lowered predation on thrips by N. cucumeris and led to a decrease in intraguild predation for both predators. Following this, the impact of apple pollen on thrips populations and predator’s maintenance on chrysanthemum greenhouse crop was assessed over a 4 weeks period. The introduction of A. swirskii with pollen provided the best control on thrips while N. cucumeris did not remain on the crop when introduced alone. Apple pollen improved thrips control by A. swirskii in chrysanthemum crops through prey numerical response and retention of predators on plants. The lowest rate of heavy dammages were observed when both predators were used together.
27

Évaluation de suppléments alimentaires pour deux espèces d’acariens prédateurs, Amblyseius swirskii et Neoseiulus cucumeris (Acari: Phytoseiidae) pour l’optimisation du contrôle biologique du thrips des petits fruits (Frankliniella occidentalis) en serriculture

Faucher Delisle, Julie 01 1900 (has links)
Ce projet de recherche a examiné le supplément alimentaire comme technique pour accroître l'efficacité de deux espèces d’acariens prédateurs, Neoseiulus cucumeris et Amblyseius swirskii contre le thrips des petits fruits Frankliniella occidentalis. Des tests en laboratoire ont vérifié l’adéquation de trois espèces de pollen – de quenouille, de maïs et de pomme – ainsi que des œufs de la pyrale Méditerranéenne de la farine pour les acariens prédateurs à l'étude. En termes de valeur rm, les œufs de pyrale et les pollens de quenouille et de pomme étaient de qualité égale pour A. swirskii, tandis que le pollen de pomme s’est distingué pour N. cucumeris. Lorsque nourris d’oeufs de la pyrale, les deux espèces ont complété leur développement avec des valeurs de rm élevées. Le pollen de pomme est apparu comme étant un supplément alimentaire accessible et adéquat pour les deux prédateurs. À court terme (période de 24h), l’influence du pollen de pomme sur les interactions trophiques (larves de F. occidentalis comme proie) et intraguildes (entre les espèces de prédateurs) sur chrysanthèmes standardisés a été examinée. La présence de pollen a considérablement réduit la prédation de N. cucumeris sur les thrips ainsi que la prédation intraguilde pour les deux prédateurs. L'impact du pollen de pomme sur les populations de thrips et sur la rétention des prédateurs dans une culture de chrysanthèmes a été évalué sur une période de 4 semaines. L'introduction de A. swirskii avec pollen a permis le meilleur contrôle des populations de thrips tandis que N. cucumeris ne s’est pas établi dans la culture lorsqu'il a été introduit seul. Le pollen de pomme a amélioré la lutte au thrips par A. swirskii dans une culture de chrysanthème via une réponse numérique de la proie et la rétention des prédateurs dans la culture. Le plus bas taux de dommages importants a été observé lorsque les deux acariens prédateurs étaient utilisés de concert. / This research investigated supplemental food source as a technique to increase the efficiency of two species of predatory mites, Neoseiulus cucumeris and Amblyseius swirskii against the western flower thrips Frankliniella occidentalis. Laboratory assays aimed to assess the suitability of three pollen species – cattail, maize and apple – and eggs of the Mediterranean flour moth as supplemental food source for the predatory mites under study. In terms of rm value, flour moth eggs, cattail pollen and apple pollen were food sources of equal quality for A. swirskii, while apple pollen appeared to stand out for to N. cucumeris. Maize pollen was a less suitable food source for both species. When fed flour moth eggs, A. swirskii and N.cucumeris completed development and showed high rm values. Apple pollen appeared to be an accessible and suitable food source for both predators. Short term (24h period) influence of apple pollen availability on trophic (F. occidentalis larvae as prey) and intraguild (between the predator species) interactions on standardized chrysanthemum was examined. It significantly lowered predation on thrips by N. cucumeris and led to a decrease in intraguild predation for both predators. Following this, the impact of apple pollen on thrips populations and predator’s maintenance on chrysanthemum greenhouse crop was assessed over a 4 weeks period. The introduction of A. swirskii with pollen provided the best control on thrips while N. cucumeris did not remain on the crop when introduced alone. Apple pollen improved thrips control by A. swirskii in chrysanthemum crops through prey numerical response and retention of predators on plants. The lowest rate of heavy dammages were observed when both predators were used together. / Projet réalisé en cotutelle avec Jacques Brodeur et Les Shipp
28

Metodologias para o dimensionamento de placas de \"granitos\" em sistemas não-aderentes de fixação / Design methodology for non adherent covering systems with \"granite\" slabs

Moreiras, Sérgio Trajano Franco 14 March 2014 (has links)
Os sistemas não aderentes de fixação com placas de \"granito\", em comparação com os métodos que empregam argamassas, exigem maior acuidade no projeto e uma avaliação estrutural criteriosa. As metodologias empregadas no país consideram apenas o parâmetro de resistência à tração na flexão na ruptura, não levando em conta outros parâmetros estruturais importantes. Para preencher esta lacuna, o presente trabalho propõe uma metodologia para dimensionamento de três sistemas não aderentes de fixação: fachadas ventiladas, pisos elevados e lajes estruturais. Três \"granitos\" brasileiros de alto valor comercial - Vermelho Capão Bonito (VCB), Preto São Gabriel (PSG) e Branco Desireé (BD) - foram submetidos a ensaios laboratoriais para a determinação do comportamento tensão versus deformação, da tensão de ruptura, dos deslocamentos verticais, do módulo de Young e do coeficiente de Poisson. Estes parâmetros foram empregados para o dimensionamento de fachadas ventiladas e de pisos elevados. Os modelos computacionais do programa STRAP foram calibrados com dados obtidos do monitoramento de protótipos de fachadas e de pisos elevados. Para fachadas ventiladas (placas de 60 x 100 cm) as espessuras calculadas foram de 30 mm para o VCB, de 25 mm para o PSG e de 55 mm para o BD. Para pisos elevados (placas de 60 x 60 cm) as espessuras foram de 35 mm para o VCB, de 30 mm para o PSG e de 35 mm para o BD. Os resultados sugerem que a especificação da espessura mínima de 20 mm, comumente usada em diversos projetos nacionais, não considera aspectos estruturais importantes. / Design on \"granite\" plates for non adherent covering systems, in comparison with mortar methods, needs a structural evaluation. The Brazilian design methodology considers only the breaking load bending tensile strength and do not consider another important structural characteristics. To fill this gap, this thesis presents a methodology for design on three \"granite\" plates for non adherent covering systems: ventilated façades, pedestal paving system and structural slab. Three Brazilian \"granites\" with great commercial acceptance - Capão Bonito Red (CBR), São Gabriel Black (SGB) and Desireé White (DW) were tested to obtain the strength versus strain behavior, the breaking load strength, the modulus of Young and the Poisson coefficient. To structural design this characteristics were applied in computational models, that were calibrated with tests data. The thickness calculated for ventilated façades (slab of 60 x 100 cm) is 30 mm for CBR, 25 mm for SGB and 55 mm for DW. The thickness calculated for pedestal paving system (slab of 60 x 60 cm) is 35 mm for CBR, 30 mm for SGB and 35 mm for DW. This results show that the thickness of 20mm applied for Brazilian practice design criteria do not consider important structural issues.
29

Metodologias para o dimensionamento de placas de \"granitos\" em sistemas não-aderentes de fixação / Design methodology for non adherent covering systems with \"granite\" slabs

Sérgio Trajano Franco Moreiras 14 March 2014 (has links)
Os sistemas não aderentes de fixação com placas de \"granito\", em comparação com os métodos que empregam argamassas, exigem maior acuidade no projeto e uma avaliação estrutural criteriosa. As metodologias empregadas no país consideram apenas o parâmetro de resistência à tração na flexão na ruptura, não levando em conta outros parâmetros estruturais importantes. Para preencher esta lacuna, o presente trabalho propõe uma metodologia para dimensionamento de três sistemas não aderentes de fixação: fachadas ventiladas, pisos elevados e lajes estruturais. Três \"granitos\" brasileiros de alto valor comercial - Vermelho Capão Bonito (VCB), Preto São Gabriel (PSG) e Branco Desireé (BD) - foram submetidos a ensaios laboratoriais para a determinação do comportamento tensão versus deformação, da tensão de ruptura, dos deslocamentos verticais, do módulo de Young e do coeficiente de Poisson. Estes parâmetros foram empregados para o dimensionamento de fachadas ventiladas e de pisos elevados. Os modelos computacionais do programa STRAP foram calibrados com dados obtidos do monitoramento de protótipos de fachadas e de pisos elevados. Para fachadas ventiladas (placas de 60 x 100 cm) as espessuras calculadas foram de 30 mm para o VCB, de 25 mm para o PSG e de 55 mm para o BD. Para pisos elevados (placas de 60 x 60 cm) as espessuras foram de 35 mm para o VCB, de 30 mm para o PSG e de 35 mm para o BD. Os resultados sugerem que a especificação da espessura mínima de 20 mm, comumente usada em diversos projetos nacionais, não considera aspectos estruturais importantes. / Design on \"granite\" plates for non adherent covering systems, in comparison with mortar methods, needs a structural evaluation. The Brazilian design methodology considers only the breaking load bending tensile strength and do not consider another important structural characteristics. To fill this gap, this thesis presents a methodology for design on three \"granite\" plates for non adherent covering systems: ventilated façades, pedestal paving system and structural slab. Three Brazilian \"granites\" with great commercial acceptance - Capão Bonito Red (CBR), São Gabriel Black (SGB) and Desireé White (DW) were tested to obtain the strength versus strain behavior, the breaking load strength, the modulus of Young and the Poisson coefficient. To structural design this characteristics were applied in computational models, that were calibrated with tests data. The thickness calculated for ventilated façades (slab of 60 x 100 cm) is 30 mm for CBR, 25 mm for SGB and 55 mm for DW. The thickness calculated for pedestal paving system (slab of 60 x 60 cm) is 35 mm for CBR, 30 mm for SGB and 35 mm for DW. This results show that the thickness of 20mm applied for Brazilian practice design criteria do not consider important structural issues.
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Improving abiotic and biotic stress tolerance in floriculture crops

South, Kaylee 13 November 2020 (has links)
No description available.

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