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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.
341

Contribution de l’imagerie dronique pour la caractérisation des paramètres biophysiques des cultures agricoles

Khun, Kosal 05 1900 (has links)
Grâce aux technologies de l’information et aux systèmes de positionnement par satellites (GNSS), l’agriculture de précision raffine l’échelle d’observation et d’intervention, du champ à la plante individuelle. La télédétection, notamment à travers les images satellitaires, a également permis de surveiller l’évolution de la culture, avec une fréquence temporelle et une résolution spatiale accrues. La vigueur de la culture est un paramètre crucial de la fertilisation, permettant d’optimiser l’apport en intrants et de générer des retombées économiques et environnementales. Plusieurs manières d’estimer la vigueur sont possibles. Pour une culture en rangs comme le maïs (Zea Mays L.), nous avons privilégié la biomasse qui servira de proxy à la vigueur. Notre étude s’appuie sur l’hypothèse que l’avènement des drones agricoles ouvrira la voie à une meilleure estimation de la vigueur. Nous supposons que la flexibilité de la plateforme combinée avec la très haute résolution spatiale (THRS) des images droniques permettra un suivi plus précis de l’évolution de la vigueur, tant dans l’espace que dans le temps – conditions critiques pour le déploiement de l’agriculture de précision. Les recherches des 15 dernières années s’appuient sur le drone pour collecter des images THRS, dont le traitement fait appel principalement à la méthode des indices de végétation, tel le NDVI. Plusieurs questions se posent : – Le recours au NDVI est-il la manière la plus efficiente d’exploiter la THRS des images droniques ? Si non, comment exploiter autrement et mieux cette imagerie ? – Attendu les contraintes de temps, la quantité de données et les impératifs logistiques, la méthode de traitement adoptée sera-t-elle suffisamment robuste ? Les concepts utilisés seront-ils simples et compréhensibles pour obtenir l’adhésion des utilisateurs finaux, c’est-à-dire les agriculteurs ? – Les capteurs à bord des drones pouvant être orientés assez librement, quels sont les effets des angles de visée sur les résultats ? D’abord, nous avons évalué la pertinence de l’approche classique, consistant à utiliser l’indice NDVI pour déterminer les paramètres de la culture. Pour cela, la plateforme dronique est comparée avec le capteur de proximité GreenSeeker. Il en découle que le drone se montre moins performant que le GreenSeeker pour l’estimation de la biomasse du maïs. Nous avons ainsi délaissé l’approche classique et opté pour un indicateur de surface apparente, extrait à l’aide des techniques de vision par ordinateur appliquées à des images RGB. Cette méthode tire profit de la THRS offerte par l’imagerie dronique et produit un proxy robuste de la biomasse, au niveau surfacique (par mètre carré) et linéaire (par rang). Nous avons aussi constaté que les résultats n’étaient pas affectés par les angles d’acquisition des images (au nadir et obliques). Partant, cette recherche ouvre la perspective à des applications de la dronautique en agriculture de précision, pour l’estimation de la vigueur et d’autres paramètres fondamentaux entrant dans les algorithmes d’optimisation des intrants. Elle offre également la possibilité d’imaginer des plateformes non-droniques pour l’acquisition des images THRS dans le contexte de la fertilisation. / Thanks to information technologies and GNSS (Global Navigation Satellite System), precision agriculture is refining the scale of observation and intervention, from the field to the individual plant. Remote sensing, in particular through satellite imagery, has also made it possible to monitor the crop dynamics, with increasing time frequency and spatial resolution. Crop vigor is a crucial parameter allowing the optimization of inputs, and consequently economic and environmental benefits. Several ways to estimate crop vigor are possible. For a row crop such as corn (Zea Mays L.), aboveground biomass has been favored and will serve as a proxy for vigor. Our study is based on the hypothesis that the recent advent of agricultural UAVs (Unmanned Aerial Vehicles) will pave the way for a better estimation of crop vigor. We assume that the flexibility of the UAV combined with the very high spatial resolution of their images will allow a more accurate monitoring of crop vigor, both in space and time – conditions which are critical for the deployment of precision agriculture. Research over the past 15 years has relied on the UAV to collect images of very high spatial resolution. However, the processing of those images is mainly based on vegetation indices, especially the NDVI. Several questions arise from the above observations: – Is the use of NDVI the most efficient way to exploit the spatial resolution of UAV images? If not, is there a better way to exploit this imagery? – How to respond to time and logistical constraints in the image processing so that it is ultimately adopted by farmers? – Since UAV-borne sensors can be oriented quite freely, what are the effects of the acquisition angles on the results? First, we assessed the relevance of the traditional approach which uses the NDVI index to determine crop parameters. To do that, we compared the UAV platform with the GreenSeeker proximal sensor. The results showed that the UAV is less efficient than the GreenSeeker in estimating corn biomass. We thus moved away from the traditional approach and opted for a method extracting the apparent leaf area, through computer vision techniques applied to RGB images. This method took advantage of the very high spatial resolution offered by UAV images and produced a robust proxy for corn biomass, at the surface (per square meter) and row levels. We also found that the results were not affected by the acquisition angles of the images (nadir and oblique). Therefore, this research opens the perspective to UAV applications in precision agriculture, for the estimation of vigor and other fundamental parameters used in input optimization algorithms. It also offers the possibility to imagine non-UAV based platforms for the acquisition of very high resolution images in the context of fertilization.
342

A Novel Mutational Approach to Uncover Genetic Determinants of Hybrid Vigor in Maize

Emily A Kuhn (16642218) 07 August 2023 (has links)
<p>Heterosis, or hybrid vigor, is a phenomenon observed in both plant and animal systems where hybrid offspring perform better when compared to their parents. For hybrid plants, this can result in increased biomass, crop yields, and vigor when compared to the inbred parents. Even though heterosis has been used in agriculture for over a century, the molecular mechanisms that result in hybrid vigor remain elusive even after years of investigation. A molecular understanding of heterosis is desirable because it will speed up the process of breeding compatible inbred lines for developing hybrid seeds, and it will provide us with the knowledge to potentially engineer inbred lines that can mimic the beneficial phenotypic effects of heterosis, eliminating the need for farmers to buy new hybrid seeds every year. The goal of this research project is to identify genes that are required for heterotic phenotypes in maize. Our working hypothesis is that a mutation in genes that are essential for heterosis will cause an altered heterotic phenotype in hybrid maize plants. To test this hypothesis, we applied combined approaches of EMS mutagenesis, trait phenotyping in field and controlled conditions, bulk segregant analysis, whole genome sequencing, and bioinformatics analysis. First, we applied a forward genetics approach to identify mutant hybrids with altered heterosis and detected potential causal genes <em>via</em> whole genome sequencing. We identified one mutation occurring in a protein coding gene (gene ID <em>Zm00001eb305590</em>) located in a region of interest on chromosome 7, whose genotypes across various samples assayed fit the observed segregation pattern of hybrid traits. This mutation leads to a moderate or high-level codon change, indicating that this gene may play a role in mediating heterosis in maize. By investigating this gene with further studies, the learned knowledge could speed up the process of hybrid maize breeding by selecting compatible inbred lines through sequencing or by engineering hybrids that have favorable alleles for this gene.</p>
343

Transformativt ledarskaps påverkan på fastighetsmäklares säljprestationer

Karlsson, Johannes, Sarocchi, Victor January 2021 (has links)
Syfte: Syftet med denna studie är att undersöka hur transformativt ledarskap påverkar svenska fastighetsmäklares säljprestationer genom dess effekt på attitydsvariablerna psykologiskt bemyndigande, upplevd själveffektivitet och medarbetarkraft samt beteendevariabeln prestationssträvan. Metod: Denna studie är grundad i en kvantitativ forskningsmetod med deduktiv ansats. En enkätundersökning har genomförts där fastighetsmäklare besvarat frågor om sig själva och sina chefer för att möjliggöra en undersökning av hur transformativt ledarskap påverkar deras säljprestationer. Resultat &amp; slutsats: Resultatet av denna studie visar att transformativt ledarskap påverkar svenska fastighetsmäklares säljprestationer positivt genom dess effekt på attitydsvariabler och prestationssträvan. Det transformativa ledarskapets positiva påverkan är dock relativt låg och resultatet indikerade på att attitydsvariablerna hos fastighetsmäklare har större positiv påverkan på varandra än vad transformativt ledarskap har på dessa. Resultatet visade även att attitydsvariablerna, specifikt medarbetarkraft, direkt påverkar säljprestationer hos fastighetsmäklare starkare än den effekt transformativt ledarskap har på säljprestation genom dess indirekta påverkan på fastighetsmäklares attityder och prestationssträvan. Examensarbetets bidrag: Denna studie bidrar med kunskap om hur transformativt ledarskap påverkar svenska fastighetsmäklares säljprestationer. Studien bidrar med resultat som visar att ledarskapet har betydelse och påverkar fastighetsmäklares säljprestationer positivt. Studien visar vidare att attitydsvariablerna själva har större betydelse för fastighetsmäklares säljprestationer, framför allt medarbetarkraft. Förslag till fortsatt forskning: Vidare forskning kan göras för att utreda om det finns andra variabler än transformativt ledarskap som påverkar fastighetsmäklares säljprestationer positivt. / Aim: The purpose of this study is to investigate how transformational leadership affects swedish real estate agents' sales performance through its effects on the attitude variables psychological empowerment, perceived self-efficacy and employee vigor and lastly the behavior variable accomplishment-striving. Method: This study is based on a quantitative research method with a deductive approach. A survey has been carried out where real estate agents responded to questions about themselves and their managers to enable an examination on how transformational leadership affects their sales performance. Result &amp; Conclusions: The results of this study show that transformational leadership has a positive effect on Swedish real estate agents' sales performance through its effect on attitude variables and accomplishment striving. However, the positive impact of transformational leadership is relatively low and the results indicate that the attitude variables of real estate agents have a greater positive impact on each other than transformational leadership has on them. The results also showed that the attitude variables, specifically employee vigor, directly affect sales performance of real estate agents more strongly than the effect transformational leadership has on sales performance through its indirect impact on real estate agents' attitudes and accomplishment striving. Contribution of the thesis: This study contributes knowledge about how transformational leadership affects Swedish real estate agents' sales performance. The study contributes with results that show that leadership is important and has a positive effect on real estate agents' sales performance. The study also shows that the attitude variables themselves are more important for real estate agents' sales performance, especially employee vigor. Suggestions for future research: Further research can be done to see if there are other variables than transformational leadership that affect real estate agents' sales performance positively.
344

THE ACUTE EFFECTS OF AEROBIC EXERCISE TYPES ON AFFECT AND COGNTION AFTER A STRESSOR

Qadir, Aneela 11 May 2015 (has links)
No description available.
345

Contribution des pratiques culturales (irrigation et fertilisation azotée) à la gestion des populations de pucerons en verger fruitier : Cas des systèmes pêcher - puceron vert du pêcher (Prunus persica - Myzus persicae) et pommier - puceron cendré (Malus domestica - Dysaphis plantaginea) / Contribution of cultural practices (irrigation and nitrogen fertilisation) to aphid management in fruit orchard : Study cases peach tree - green peach aphid (Prunus persica - Myzus persicae) and apple tree - rosy apple aphid (Malus domestica - Dysaphis plantaginea)

Rousselin, Aurélie 21 December 2016 (has links)
Les pucerons sont des ravageurs importants des principales espèces fruitières en France, pêcher et pommier notamment. Dans le but de réduire l’usage des produits phytosanitaires, différentes alternatives sont envisagées pour contrôler les pucerons en verger. Nous avons commencé ce travail de thèse par une synthèse des différentes méthodes alternatives de contrôle envisageables et leur positionnement au cours des différentes étapes du cycle biologique du puceron. Puis nous avons étudié les effets de la modulation des caractéristiques de la plante hôte, via les pratiques culturales, sur l’abondance des pucerons. Notre étude se base sur l’hypothèse « Plant Vigor » qui énonce que les insectes phytophages sont plus performants sur les plantes ou les organes de forte vigueur. Par conséquent, sur nos deux dispositifs expérimentaux factoriels nous avons combiné des suivis dynamiques de croissance végétative et d’abondance de pucerons : Prunus persica - Myzus persicae (2 niveaux d’irrigation × 2 niveaux d’apport azoté) et Malus domestica - Dysaphis plantaginea (2 niveaux d’irrigation × 2 génotypes d’arbre). Les facteurs ont été choisis pour leur impact potentiel sur la croissance végétative et la qualité nutritionnelle de la plante hôte. Les expérimentations ont été menées sur de jeunes arbres en pot, ne portant pas de fruit. Au niveau du rameau, l’abondance des pucerons est positivement corrélée à la croissance végétative sur les deux systèmes étudiés. Sur pêcher, la relation disponibilité en azote et abondance de pucerons semble être médiée par le fort impact de l’azote sur la croissance végétative. L’effet négatif de la restriction hydrique sur l’abondance de pucerons ne semble pas lié à un impact sur la croissance végétative. Aussi sur le second système étudié : pommier-puceron cendré, nous avons choisi de faire varier les apports en eau et de travailler sur deux génotypes, pour tester la généricité de la réponse observée. A l’échelle du rameau, l’effet de la restriction hydrique sur l’abondance de pucerons est négatif pour un génotype et positif pour l’autre. Par contre à l’échelle de l’arbre, sur les deux génotypes l’abondance de pucerons est corrélée positivement à la croissance végétative et la restriction hydrique impacte négativement l’abondance de pucerons, ce qui suggère que la performance des pucerons est limitée sur les arbres en restriction hydrique par une autre composante que la vigueur de l’arbre. Ce travail de thèse montre que la restriction hydrique et le contrôle de la vigueur via les apports azotés peuvent s’avérer être des leviers pour le contrôle des pucerons en verger fruitier. Cependant les relations mises en évidence sont dépendantes du génotype, ainsi que de l’échelle d’analyse. Il reste à évaluer l’applicabilité de telles mesures sur des arbres en conditions de production, en prenant en compte notamment l’effet des restrictions hydrique et azotée sur la production fruitière. / Aphids are major pests of important fruit trees in France, especially peach and appletrees. In order to reduce chemical use, various alternatives can be implemented for themanagement of aphids in orchards. This thesis starts by a review of the different alternativemanagement methods and their positioning at different aphid life cycle stages. Then our workfocuses on the study of the effects of modulation of host plant characteristics, through culturalpractices, on aphid abundance. Our study is based on the Plant Vigor Hypothesis which statesthat phytophagous insects are more performant on vigorous plant or organ. Thus, in theexperimental part we combined dynamic assessment of vegetative growth and aphid abundanceduring two factorial experiments: Prunus persica – Myzus persicae (2 levels of water supply ×2 levels of nitrogen supply) and Malus domestica – Dysaphis plantaginea (2 levels of watersupply × 2 tree genotypes). We chose those factors for their possible impact on vegetativegrowth and nutritional quality of the host plant. We conducted the experiments on young nonbearingpotted trees. At shoot scale, aphid abundance is positively correlated to vegetativegrowth for both studied systems. On peach tree, the positive impact of nitrogen availability onaphid abundance seems to be mediated by the strong positive impact of nitrogen on vegetativegrowth. The negative effect of water restriction on aphid abundance seems to be unrelated toan impact of water availability on vegetative growth. Thus on the second studied system: appletree – rosy apple aphid, we chose to vary water supply and to work on two genotypes to test thegenericity of the observed pattern. At shoot scale, water restriction has a positive effect on aphidabundance on one tree genotype and a negative effect on the other one, whereas at tree scalefor both tree genotypes aphid abundance is positively correlated to vegetative growth and waterrestriction negatively impacts aphid abundance. These results suggest that aphid performanceon water restricted trees is limited by another host plant characteristics than vegetative growth.This thesis shows that water restriction and vigour management through nitrogen fertilizationcan be implemented to manage aphids in fruit orchards. However, the patterns evidenced aredependent on tree genotype and on the scale of analysis. The applicability of these alternativemethods remains to be assessed in producing orchards, taking into account the effects of waterand nitrogen restrictions on fruit production.
346

Doses de regulador vegetal em sistema de semeadura convencional e direta sobre a produtividade, teor de nutriente nas folhas e nas sementes e qualidade fisiológica das sementes de três cultivares de feijão /

Abrantes, Fabiana Lima. January 2011 (has links)
Orientador: Marco Eustaquio de Sá / Banca: Orivaldo Arf / Banca: Salatiér Buzetti / Banca: Rogério Peres Soratto / Banca: Charline Zaratin Alves / Resumo: A maioria dos trabalhos com diferentes sistemas de manejo do solo e com uso de regulador vegetal (citocinina, giberelina e auxina) busca obter resultados quanto a aumentos na produtividade. Já, quanto ao seu efeito nos teores de nutrientes nas folhas e sementes e na qualidade fisiológica das sementes produzidas nessas condições há carência de informações. Desta forma, o objetivo deste trabalho foi avaliar o desenvolvimento, produtividade, nutrientes nas folhas e sementes e qualidade fisiológica das sementes de feijão, cultivares Carioca Precoce, IAC Apuã e IAC Alvorada, em função do uso de regulador vegetal, via foliar, em sistema convencional e plantio direto em implantação, no inverno com uso de irrigação. A pesquisa foi conduzida em 2009 e 2010, no Município de Selvíria/MS. Realizaram-se três experimentos com os cultivares Carioca Precoce, IAC Apuã e IAC Alvorada, em blocos casualizados, em faixas, com quatro repetições. Os fatores foram: sistemas de semeadura convencional com incorporação da palhada do milheto ao solo e direta sobre a palhada do milheto e cinco doses do regulador vegetal (0; 1,0; 2,0; 3,0 e 4,0 L p.c ha-1) composto por três hormônios vegetais: cinetina, ácido giberélico e ácido indolbutírico, aplicadas em R5. Avaliou-se: clorofila e nutrientes foliares, características agronômicas e produtivas, teor de proteína e nutrientes nas sementes e a qualidade fisiológica das sementes através dos testes de: germinação, primeira contagem, emergência de plântulas em campo, índice de velocidade de emergência, altura de plântula, massa da matéria seca de plântula, envelhecimento acelerado, teste de frio sem solo e condutividade elétrica. O plantio direto mesmo em fase de implantação propiciou: aumento na clorofila e nos teores foliar de N, P e Mg variando em função do cultivar e do ano; e de maneira geral, considerando os três cultivares... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The most studies with different systems of soil management and use of plant growth regulator (cytokinin, auxin and gibberellin) search results as increases in productivity. Already, in its effect on nutrient concentrations in leaves and seeds and physiological quality of seed produced under these conditions there is a lack of information. Thus, the objective was to evaluate the development, productivity, nutrients in the leaf and seeds and physiological seed quality of common bean cultivars, Carioca Precoce, IAC Apuã and IAC Alvorada, depending on the use of growth regulators on leaf, in the conventional or no-tillage system in the implantation, in the winter with irrigation use. The research was conducted in 2009 and 2010, in Selvíria - MS State. They were conducted three experiments with varieties Carioca Precoce, IAC Apuã and IAC Alvorada, in a randomized blocks design in strips with four replicates. The treatments were: conventional tillage system with millet straw incorporation to the soil or directly over the millet straw, and five doses of the plant growth regulators (0, 1.0, 2.0, 3.0 and 4.0 L cp ha -1) which consists of three plant hormones, kinetin, gibberellic acid and IBA, applied at R5. It was evaluated: chlorophyll and foliar nutrients, agronomic and productive characteristics, protein and nutrients in the seeds and physiological quality of seeds through the tests of germination, first count, seedling emergence in the field, speed of emergence index, seedling height, mass of dry matter of seedlings, accelerated aging, cold test without soil and electric conductivity. The no-tillage even in implantation phase resulted in: increased leaf chlorophyll and on N, P and Mg, depending on the cultivar and year, and in general, considering the three cultivars used, it was the better development of plants and seed yield. The growth regulator did not affect the levels... (Complete abstract click electronic access below) / Doutor
347

Simulação de danos mecânicos em sementes de feijão carioca durante o processo de beneficiamento / Simulation of mechanical damage in seeds of bean carioca during improvement process.

QUEIRÓZ, José Ramos de. 01 July 2018 (has links)
Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-07-01T14:30:28Z No. of bitstreams: 1 JOSÉ RAMOS DE QUEIRÓZ - DISSERTAÇÃO PPGEA 2011..pdf: 10586067 bytes, checksum: 59de6a3167d2dba506f41cae2f3984bb (MD5) / Made available in DSpace on 2018-07-01T14:30:28Z (GMT). No. of bitstreams: 1 JOSÉ RAMOS DE QUEIRÓZ - DISSERTAÇÃO PPGEA 2011..pdf: 10586067 bytes, checksum: 59de6a3167d2dba506f41cae2f3984bb (MD5) Previous issue date: 2011-09 / O objetivo deste trabalho foi desenvolver um equipamento que simule os danos mecânicos nas diversas etapas do processo de beneficiamento e avalie em cada etapa, as alterações da qualidade fisiológica (germinação e vigor, massa da matéria seca) das sementes de feijão carioca e também as alterações de suas características físicas (pureza física, massa de milsementes, massa específica aparente, porosidade e danos mecânicos). Inicialmente, fez-se um teste em uma UBS (Unidade de Beneficiamento de Sementes) através do qual foram levantados os parâmetros: distância, velocidade e tempo de duração do processo de beneficiamento na UBS para viabilizar a construção do simulador. As etapas estudadas foram recepção, prelimpeza, secagem nas temperaturas de 25, 35 e 45°C, limpeza, seleção e tratamento fúngico/ensaque. Concluiu-se, neste trabalho, que a qualidade fisiológica das sementes de feijão não é alterada significativamente da etapa de recepção até o momento anterior à secagem. Após a secagem a semente de feijão sofre perda significativa de sua qualidade fisiológica, embora não seja até a etapa final de beneficiamento. A perda de germinação e o vigor foram em média de 11,55 e 23,78 pontos percentuais, respectivamente; no entanto, as sementes apresentam no final do processo poder germinativo acima do mínimo indicado para sua comercialização (86 a 82,67%). / The objective of this project was to develop equipment that simulates the mechanical damages in various beneficiai processing steps and evaluates in each step the physiological quality changes (germination and vigor) of the seeds of carioca beans as well as the changes of their physical characteristics (purity fisic, mass of one thousand seeds, apparent specific mass, porosity and mechanical damages). First, a test was done in one SPU (Seeds Processing Unit) through which parameters were inventoried: distance, speed and time processing duration in the SPU to make possible the construction of the Simulator. The steps studied were pre- cleanliness, drying under temperatures of 25, 35 and 45°C cleanliness, selection and treatment of fungus and bagging. One concluded that the physiological quality of the bean seeds is not significant from the time when it gets to the SPU until prior to the time of drying. After drying the bean seed suffers important loss of its physiologic quality, although does not change up to the final beneficiai process step. The loss of germination and vigor carne at a rate of 11.55% and 23.78% respectively; but the seeds presented germination strength above the minimum indicated to commercialize them (86% to 82.67%).
348

Qualidade de sementes de soja avaliadas pelo teste de tetrazólio: estudo de caso na empresa Dimicron / Soybean seed quality valued by test tetrazolium: a case study in the company Dimicron

Uhde, Shirlei 17 November 2014 (has links)
Submitted by Maria Beatriz Vieira (mbeatriz.vieira@gmail.com) on 2017-03-03T15:30:24Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) dissertacao_shirlei_uhde.pdf: 798758 bytes, checksum: 087cc2c455112b068e7753167b47f0d8 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-03-09T17:59:02Z (GMT) No. of bitstreams: 2 dissertacao_shirlei_uhde.pdf: 798758 bytes, checksum: 087cc2c455112b068e7753167b47f0d8 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-03-09T18:00:44Z (GMT) No. of bitstreams: 2 dissertacao_shirlei_uhde.pdf: 798758 bytes, checksum: 087cc2c455112b068e7753167b47f0d8 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-03-09T18:00:51Z (GMT). No. of bitstreams: 2 dissertacao_shirlei_uhde.pdf: 798758 bytes, checksum: 087cc2c455112b068e7753167b47f0d8 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2014-11-17 / Sem bolsa / O presente trabalho teve como objetivo fazer um levantamento da qualidade fisiológica de sementes de soja, das categorias S1 e S2, analisadas no Laboratório de Analises de Sementes da Dimicron Química do Brasil Ltda., usando o teste de tetrazolio, para caracterizar as características fisiológicas: viabilidade, vigor, danos mecânicos, danos por umidade, danos por percevejos, causas da perda da viabilidade, classificação do vigor, relacionar nível de sementes de mais alto vigor Para o trabalho, foram coletados os dados das analises das safras 2008/2009, 2009/2010, 2010/2011 e 2011/2012, referente às informações obtidas dos testes de tetrazólio aplicados nas amostras de lotes de sementes das categorias S1 e S2 que foram analisadas. Foram examinados os resultados de 481 lotes analisados, sendo 309 lotes da categoria S1 e 172 lotes da categoria S2. Os parâmetros empregados para avaliar a qualidade fisiológica das sementes foram: viabilidade (TZ 1-5), vigor (TZ 1-3), danos mecanicos (TZ 1-8), danos por umidade (TZ 1-8), danos por percevejo (TZ 1-8). Os resultados obtidos permitem concluir que: As maiores percentagens de lotes de alto vigor foram obtidas nas safras de 2008/2009 e 2009/2010, para ambas classes de sementes. Os danos mecânicos e de umidade são os mais freqüentes em sementes de soja. / This study aimed to survey the physiological quality of soybean seeds, S1 and S2 categories analyzed in LABORATORY analysis of seeds of Dimicron Chemistry of Brazil Ltda., Using the tetrazolium test to characterize the features physiological: feasibility, force, mechanical damage, moisture damage, bedbugs for damages, loss of viability of the causes of force classification, relate highest level of seed vigor for work, we collected data from the analysis of crops 2008/2009, 2009/2010, 2010/2011 and 2011/2012, referring to the information obtained from tetrazolium tests applied in samples of seed lots of S1 and S2 categories that were analyzed. We examined the results of 481 lots, with 309 lots category S1 and S2 172 lots category. The parameters used to evaluate the physiological quality of seeds were: viability (TZ 1-5), vigor (TZ 1-3), mechanical damage (TZ 1-8), moisture damage (TZ 1-8), damages for bug (TZ 1-8). The results showed that: The highest percentages of lots of high vigor were obtained for crop years 2008/2009 and 2009/2010, for both seed classes. Mechanical damage and humidity are the most frequent in soybean seeds.
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Herança genética e potencial de armazenamento de sementes de híbridos de milho / Genetic inheritance and storage potential of corn hybrids seeds

Capelaro, Ademir Luiz 28 March 2014 (has links)
Made available in DSpace on 2014-08-20T13:44:37Z (GMT). No. of bitstreams: 1 tese_ademir_luiz_capelaro.pdf: 530051 bytes, checksum: 5341eb64d3d21ee5323d0a427e36b506 (MD5) Previous issue date: 2014-03-28 / The present study aimed to evaluate the effects of genetic inheritance in the physiological quality and the storage potential of some corn hybrids seeds produced in the field and stored in two different environments: cold room and common warehouse, for a period of eighteen months. To this study were produced seeds from six corn hybrids by crossing a group of three male parental lines with two female parental lines. Seeds from these hybrids were produced in the Syngenta Production Research field area, located at Tupaciguara-MG, under a high technology environment/condition with a necessary isolation in order to prevent any kind of contamination between their parents. Harvest was done in spikes and after drying and processing, 10 kg of seeds samples each hybrid and parent lines corresponding to 20R size were separated. Then these samples were divided in two sub-samples of 5 kg each one and storage in two different environments: cold room at 10 º C and 60 % RH and common warehouse in natural enviroment (25 - 35° C and 30 - 90% RH). Seeds quality for the two environment conditions was evaluated by using the germination test, acelerating aging test (EVA) and cold test, for a period of eighteen months. The statistical design was completely randomized factorial 3x5 for each hybrid and male and female parent, in five evaluation periods, performed separately for each storage condition, with four replications in case of germination and three replications for each treatment in case of accelerated aging test and cold test. According the results was possible to conclude that the physiological quality of the seeds and their longevity (shelf life) was similar for all hybrids, independent of the different combination of their respective male and female. Also the hybrids have ever presented better performance of their respective parental lines. In all situations evaluated was observed that the hybrids presented higher performance to physiological quality than their respective parent lines, indicating that the effects of the heterosis was very important. / O presente trabalho teve o objetivo de avaliar o efeito da herança genética na qualidade e no potencial de armazenamento de sementes de híbridos de milho, produzidas em condições de campo e armazenadas em dois ambientes diferentes: armazém climatizado e armazém convencional. Para tanto, foram produzidas sementes de seis híbridos simples de milho, através do cruzamento de um grupo de três linhagens parentais masculinas com duas linhagens parentais femininas. As sementes dos referidos híbridos foram produzidas no campo de Pesquisa de Produção da Syngenta Seeds, localizada no município de Tupaciguara/MG, em condições de alta tecnologia e com todos os isolamentos necessários para evitar qualquer tipo de contaminação entre os parentais. A colheita foi realizada em espigas que após a sua secagem e beneficiamento, originaram dez kg de sementes de cada um dos genótipos utilizados, híbridos e linhagens parentais, separadas em peneira 20R. Em seguida esta amostra foi dividida em duas sub-amostras de cinco kg, sendo cada uma delas armazenadas em dois diferentes ambientes: armazém climatizado com 10 ºC e 60 % UR; armazém convencional em condições de ambiente natural (25 a 35° C e 30 a 90% UR). A qualidade das sementes, para as duas condições de armazenamento, foi avaliada pelo teste de germinação, teste de envelhecimento acelerado e teste de frio. O delineamento estatístico utilizado foi inteirarmente casualizado em esquema fatorial 3x5, para cada híbrido e parental masculino e feminino, em cinco épocas de avaliação, realizadas separadamente para cada condição de armazenamento, com quatro repetições para cada tratamento no caso do teste de germinação e três repetições para cada tratamento nos testes de vigor envelhecimento acelerado e teste de frio. Quanto a significância, realizou-e análise de regressão polinimial. Concluiu-se que a qualidade e o potencial de armazenamento das sementes foram semelhantes para todos os híbridos, independentemente da combinação entre os respectivos parentais masculinos e femininos. O comportamento de cada híbrido foi independente do parental masculino utilizado no cruzamento com cada um dos parentais femininos. Em todas as situações avaliadas observou-se que os híbridos apresentaram uma qualidade fisiológica bastante superior em relação aos seus respectivos parentais, masculinos e femininos, indicando que houve um efeito da heterose na qualidade fisiológica das sementes.
350

The Effects of Nomophobia on Employee Engagement

Daniel, Amber Joy Shirlyn 04 May 2022 (has links)
No description available.

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