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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.
111

Sistemas de aplicação de subdoses de glifosato e regulador de crescimento em algodoeiro /

Ferrari, João Vitor. January 2015 (has links)
Orientador: Enes Furlani Junior / Banca: Luiz Henrique Carvalho / Banca: Edivaldo Cia / Banca: Marco Eustáquio de Sá / Banca: Fernando Tadeu de Carvalho / Resumo: A cotonicultura apresenta destaque no cenário mundial, pois emprega tecnologia avançada representada por maquinários modernos e técnicos com grande experiência de campo, elevados investimentos e pela diversidade de utilização da pluma. O objetivo deste trabalho foi avaliar o algodoeiro cv. FMT 701 em função de sistemas de aplicação de subdoses de glifosato e regulador de crescimento. O delineamento experimental foi o de blocos ao acaso em esquema fatorial 6x2 com 4 repetições, perfazendo um total de 48 parcelas, compostas por: a- número de aplicações da subdose do glifosato (20 g e.a. (equivalente ácido) ha -1 ): (zero, uma, duas, três, quatro e cinco), aplicadas via foliar respectivamente aos 40; 40 e 50; 40, 50 e 60; 40, 50, 60 e 70 e 40, 50, 60, 70 e 80 dias após emergência (d.a.e.) das plantas; e b- manejo do regulador de crescimento em aplicação foliar (50 g i.a. (ingrediente ativo - cloreto de mepiquat) ha -1 ) sendo por aplicações de forma parcelada (3 dias após a aplicação da subdose do glifosato) ou de forma única aos 70 d.a.e. (nas parcelas que não receberam a subdose); e sem aplicação. A cultivar de algodão FMT 701 submetida a duas aplicações da subdose do glifosato apresenta maior crescimento em altura e de concentração de Mg foliar além de maior número de capulhos por planta e produtividade de algodão em caroço quando associado ao cloreto de mepiquat. A utilização do regulador de crescimento proporciona aumento do diâmetro do caule, concentração de N e Mg foliar e índice SPAD de clorofila, e diminui o comprimento de ramos reprodutivos. Cinco aplicações da subdose de glifosato associadas à utilização do cloreto de mepiquat proporcionam redução de altura de plantas, produtividade e índice de micronaire no algodoeiro / Abstract: The cotton crop has featured on the world stage because employs advanced technology, represented by modern machinery and technicians with great field experience, high investments and the diversity of the plume use. The objective of this study was to evaluate the cotton cv. FMT 701 in function of application systems of glyphosate low dose and growth regulator. The experimental design was a randomized block in 6x2 factorial with four replications, totaling 48 plots with: a- number of glyphosate low dose applications (20 g a.e. (acid equivalent) ha -1 ): (zero, one, two, three, four and five), foliar applied respectively to 40; 40 and 50; 40, 50 and 60; 40, 50, 60, 70 and 40, 50, 60, 70 and 80 days after emergence of plants (d.a.e.); and b- managing of the growth regulator for foliar application (50 g a.i. (active ingredient - mepiquat chloride) ha -1 ) being split application form (3 days after application of glyphosate low dose) or only way at 70 d.a.e. (in plots that didn't receive a low dose); and without application. The cotton cultivar FMT 701 submitted to two applications glyphosate low dose has increased the height and leaf Mg concentration and greater number of bolls per plant and cotton seed yield when combined with mepiquat chloride. The use of the growth regulator provides increased stem diameter, leaf Mg and N concentration and SPAD chlorophyll content, and decreases the length of reproductive branches. Five applications of glyphosate low dose associated with the use of mepiquat chloride provide height plant reduction, yield and micronaire index in the cotton crop / Doutor
112

Evolução dos comportamentos de preparação do substrato para o cultivo do fungo simbionte e cuidados com a cria, rainha e alados em formigas da tribo Attini (Hymenoptera: Formicidae) /

Diniz, Eduardo Arrivabene. January 2008 (has links)
Orientador: Odair Correa Bueno / Banca: Luiz Carlos Forti / Banca: Ana Paula Protti de Andrade Crusciol / Banca: Maria Santina de Castro Morini / Banca: Sulene Noriko Shima / Resumo: O presente trabalho teve como objetivo o estudo da evolução dos comportamentos de preparação do substrato, cuidado com a cria e cuidado com a rainha e alados em formigas cultivadoras de fungo. Estas formigas pertencem à tribo Attini, subfamília Myrmicinae, e ocorrem exclusivamente no continente americano. Esta tribo contém aproximadamente 230 espécies, porém pouco se conhece da biologia da maioria delas, graças ao fato de serem extremamente crípticas e de não apresentarem importância econômica, como as formigas cortadeiras, que são as mais estudadas. Foram utilizadas seis espécies, que representam bem os diversos níveis da filogenia da tribo: Acromyrmex disciger, Apterostigma pilosum, Mycetarotes parallelus, Myrmicocrypta sp., Trachymyrmex fuscus e Trachymyrmex sp. nov. Os comportamentos foram estudados em ninhos mantidos em laboratório, com o auxílio de micro-câmeras e um aparelho gravador de vídeo. Os comportamentos foram analisados, caracterizados e quantificados. Os resultados foram divididos em três capítulos de acordo com o tipo de comportamento. No capítulo sobre a evolução dos comportamentos de preparação do substrato foi observado que, basicamente, o processo evoluiu no sentido de aumentar a capacidade das operárias em decompor inicialmente o substrato. As espécies basais, A. pilosum, M. parallelus e Myrmicocrypta sp. apresentaram um processamento mais simples com um número menor de comportamentos e principalmente sem os comportamentos do tratamento químico, que é responsável pela fragmentação do substrato ao mesmo tempo em que ele é tratado com enzimas digestivas. As duas espécies do gênero Trachymyrmex apresentaram um processo mais complexo com grande participação do tratamento químico. Em A. disciger, que é uma cortadeira, há uma intensa especialização do sistema de castas para o aumento da eficiência... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This work aims to study the evolution of the behaviors of substrate preparation, brood, queen and winged forms care in fungus growing ants. These ants are included in the tribe Attini, subfamily Myrmicinae, and occur exclusively in the american continent. This tribe contains approximately 230 species, but little is known about the biology of most of them, tanks to the fact that they show very cryptic habits and are not economically important, like the leaf cutting ants, which are the most studied. Six species were used in this work, which represent well all the levels of the phylogeny of the tribe: Acromyrmex disciger, Apterostigma pilosum, Mycetarotes parallelus, Myrmicocrypta sp., Trachymyrmex fuscus and Trachymyrmex sp. Nov. The behaviors were studied in laboratory nests, with a set of micro cameras and a video recording device. The behaviors were analyzed, characterized and quantified. The results were summarized and discussed in tree chapters, arranged by type of behavior. In the chapter about the evolution of the substrate preparation behaviors, basically it is assumed that this process evolved in order to develop the capacity of previously decompose the substrate by the workers. In the basal species, A. pilosum, M. parallelus and Myrmicocrypta sp. this process is very simple with a small number of behaviors and principally without the behaviors of chemical treatment, which are responsible for the fragmentation of the substrate as it is treated by with digestive enzymes. In the two species of the genus Trachymyrmex, the process became more complex and showed a greater participation of these behaviors. A. disciger, witch is a leaf cutting ant, showed an extensive specialization of physical castes in all the phases of the process which elevated it's efficiency. In the chapter about the evolution of the behaviors of brood care... (Complete abstract click electronic access below) / Doutor
113

The phloem unloading and sucrose-sequestration pathway in the internodal stem tissue of the Saccharum hybrid var. NCo376

Gerber, Jacqués January 2001 (has links)
Internodes 5-8, 10, 13 and 15 of Saccharum sp. var. NCo376 were examined for evidence of symplasmic phloem unloading of sucrose from the phloem, via the bundle sheath to the storage parenchyma. The vascular bundle possesses wellisolated phloem comprised of large diameter sieve elements and small diameter companion cells. A layer of phloem parenchyma surrounds the phloem, except where the phloem abuts the crushed protophloem. Outside this is a sclerenchymatous sheath, directly endarch to a parenchymatous bundle sheath, which is surrounded by storage parenchyma. The bundle sheath is interrupted at the centrifugal pole of the vascular bundle by a phloem fibre cap. Scanning Electron Microscopy revealed plasmodesmal fields throughout the bundle sheath and pith tissue. Transmission Electron Microscopy studies provided evidence of plasmodesmal occlusion, but not in all tissues. Aniline blue reactions under UV light indicate the presence of occluded plasmodesmal fields at the phloem parenchyma / sclerenchymatous sheath interface, and in localised regions of cells which are smaller than the surrounding storage parenchyma cells. This suggests a symplasmic transport pathway at these locations, and, based on these positive aniline blue reactions, with regulation via callose-mediated transplasmodesmal transport. Osmotic stress experiments, which included the addition of Ca2+, did not reveal further callose occlusion in the parenchyma, suggesting that the plasmodesmata in these regions may be closed via a noncallosic mechanism. Dye-coupling studies, using Lucifer Yellow (LYCH), which was iontophoretically injected following turgor-pressure equalisation, showed only rare, limited symplastic transport, usually only between the injected cell and one adjacent cell. Most injections did not result in transport of LYCH, suggesting either a lack of plasmodesmal connectivity, occlusion, or gating of any plasmodesmata present. This limited symplasmic transport, combined with the presence of occluded plasmodesmata at the phloem parenchyma / sclerenchymatous sheath interface suggests the presence of a two-domain phloem-unloading pathway. While symplastic transport may occur from the phloem to the sclerenchymatous sheath, further sucrose transport to the storage parenchyma appears to proceed apoplasmically from the sclerenchymatous sheath / bundle sheath interface, and into storage parenchyma cells across the cell wall and cell membrane via specialised sucrose transporters.
114

Growing Up Lesbian in the Rural Deep South: "I Only Knew I was Different"

Gaddis, Lorraine Kay 30 April 2011 (has links)
Lesbians have historically lived in obscurity and isolation because living outwardly as a lesbian carried with it the almost certain loss of social standing, family, and friends (Blando, 2001). For lesbians who grew up in the Deep South, isolation and the pressure to conform was greater than anywhere in the United States (Barton, 2010). Most Deep Southerners were homophobic, especially in rural areas where people were deeply religious and had little exposure to sexual minorities. The researcher used a qualitative phenomenological approach to explore the meaning and significance of growing up lesbian in the rural Deep South. The sample included 12 Caucasian lesbians, ages 45 to 62. Four clusters of themes emerged from the interviews. Those clusters were: (1) emerging sexuality, (2) the mark of fatal difference, (3) denial of lesbian identity, and (4) conforming to Deep Southern social mores. Themes within those clusters described how delays in both lesbian identity development (Cass, 1984) and psychosocial development (Erikson, 1975) occurred in each of the participants because of the intensely religious and homophobic environments in which they were raised. Denunciation of participants' personal identities began with the first expressions of their sexual identities in elementary school. Ridiculed at a young age because of attractions to girls, participants cycled back through developmental crises involving shame, doubt, and inferiority. They entered adolescence disturbed about their developing sexualities, to discover that parents and faith-based communities were homophobic. Therefore, at the time when participants faced the most critical developmental crises of their lives (Erikson, 1975), they feared rejection by their parents, communities, and God. Participants sought to suppress or deny their lesbianism. Suppression of lesbian identity came with emotional and developmental costs, including substance abuse, unwanted marriages, and role confusion. Unable to find needed resources and role models, participants conformed to the social mores of the rural community for periods ranging from five to twenty years. Eventually, each participant in this study left her rural origins to begin claiming her lesbian identity. Retrospectively, each woman recognized that in the era in which they grew up, communities in the rural Deep South demanded conformity and resisted allowing members to individuate. Thus, participants in this study entered adulthood, and sometimes middle age, with a number of unresolved developmental crises, particularly as those crises related to sexual orientation.
115

Remaking labour, reshaping identity : cotton, commoditization and the culture of modernity in northwestern Zimbabwe

Worby, Eric January 1992 (has links)
No description available.
116

Use of gel additives for fluid drilled tomatoes

Minero Amador, Adolfo. January 1986 (has links)
No description available.
117

Shady Transactions: Three Essays on the Underground Economy

Tedds, Lindsay M. 07 1900 (has links)
<p> The term "underground economy" refers to output that is produced, and income that is generated, by agents who hide this fact from authorities. There has been a recent resurgence in interest in the underground economy and this interest has predominantly been stimulated by the perception that the underground economy is sizeable and growing. This dissertation is comprised of three essays, the goals of which are to provide empirical measures of underground activity.</p> <p> The first paper in this dissertation applies a modeling technique that treats the underground economy as an unobservable or latent variable and incorporates multiple indicator and multiple causal (MIMIC) variables to estimate a time-path of the size of broadly defined underground economy. Using macroeconomic Canadian data, the results indicate that the underground economy grew steadily over the sample period: from 7.5% of Gross Domestic Product (GDP) in 1976 to about 15.3% in 2001.</p> <p> The second paper uses microeconomic data and proposes a nonparametric expenditure-based approach to obtain estimates of income under-reporting by self- employed households. The approach is illustrated by estimating the effect of the Canadian Goods and Services Tax (GST) on income under-reporting. It is found that the difference between true and reported self-employment income is larger for households at the lower end of the self-employment income distribution and that there was no statistically significant change in under-reporting behaviour following the implementation of the GST.</p> <p>The third paper investigates the characteristics of businesses that engage in tax non-compliance using a survey of firms from around the world. Overall, small firms tend to be less compliant than larger firms. In addition, foreign owned firms, exporters, and firms that have audited financial statements are found to be more compliant but quite surprisingly, government ownership does not result in increased tax compliance. Finally, the existence of organized crime, high taxes, and government corruption all result in lower compliance.</p> / Thesis / Doctor of Philosophy (PhD)
118

Tomato growth as influenced by nutrient solution concentration and soilless media components /

Mills, Gretchen E. 01 January 2000 (has links) (PDF)
No description available.
119

Growing Up & Other Important Mistakes

Christman, Elizabeth E. W. 12 June 2013 (has links)
No description available.
120

Morphogenesis and Physiology of Malus Tissues and Cells in Vitro

Pua, Eng-Chong January 1983 (has links)
No description available.

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