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Structural Analysis of the 50S Ribosomal Stalk / Strukturelle Analyse des 50S ribosomalen FortsatzesDiaconu, Mihaela Stefania 05 July 2006 (has links)
No description available.
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Considerações sobre o manejo de irrigação na produtividade e qualidade de gemas de cana-de-açúcar para viveiros de mudas-pré-brotadas (MPB) / Water management considerations on productivity and quality of sugarcane seedlings to the formation of bud chips nurseryFraga Junior, Eusimio Felisbino 29 April 2015 (has links)
O cultivo da cana-de-açúcar depara-se com a falta de tecnologias alternativas inovadoras para impulsionar sua produtividade diante dos crescentes custos de mão de obra e insumos, tornando-se essencial aumentar a produtividade da cana de forma sustentável. A cana-de-açúcar é comercialmente plantada, utilizando-se cortes de toletes ou gemas. Este método de cultivo está se tornando gradualmente antieconômico, devido ao elevado custo das \"áreas de viveiros\" usadas para a renovação de canaviais, que demandam mais de 20 por cento do custo total de produção para renovação/novos plantios. Dessa forma, necessita-se de métodos alternativos de plantio, que impulsionem a produtividade da cana-de-açúcar sobre princípios de um planejamento adequado; entre outras práticas, devem estar inclusas a formação de viveiros sadios, com otimização de áreas destinadas à multiplicação de mudas e também a escolha das melhores opções entre os materiais genéticos para a formação do canavial. Este trabalho baseia-se na hipótese de que, para viveiros de cana-de-açúcar, exista uma combinação mais adequada entre a lâmina de irrigação/intensidade do déficit hídrico e a posição da gema ao longo do colmo; desta forma, aumenta-se a produtividade de gemas de cana-de-açúcar, que serão utilizadas no plantio do sistema de mudas-pré-brotadas (MPB). O objetivo deste trabalho foi avaliar, no que se refere ao viveiro de mudas, o efeito de quatro lâminas de irrigação, quatro intensidades de déficit hídrico na fase de maturação, quatro posições ao longo do colmo para oito variedades de cana-de-açúcar irrigadas por gotejamento, assim como também a produtividade por área e os custos de produção de gemas viáveis de cana-de-açúcar. O experimento foi conduzido no município de Piracicaba - SP, no Departamento de Engenharia de Biossistemas da Escola Superior de Agricultura \"Luiz de Queiroz\" (ESALQ/USP), em ambiente protegido (estufa). O delineamento experimental adotado foi em blocos inteiramente aleatorizados, com três blocos completos. Os tratamentos foram distribuídos em esquema fatorial (4x4x4x8), totalizando-se assim 511 tratamentos e 1536 parcelas experimentais. Os tratamentos testados foram: lâmina de irrigação ao longo do ciclo, com quatro níveis (Lâmina); intensidade do déficit hídrico na fase final do ciclo para maturação da cana-de-açúcar, com quatro estratégias de restrição hídrica (Maturação); posição da gema ao longo do comprimento do colmo, com quatro posições (Posição); e variedade comercial de cana-de-açúcar, com oito variedades (Variedade). Considerando-se que o presente estudo foi desenvolvido através de irrigação por gotejamento de alta frequência sob irrigação plena e irrigação com déficit, pode-se concluir que: a) a lâmina de irrigação que repõe o total de água requerido com alta frequência (L100) promove um aumento médio de 42% no total de gemas viáveis produzidas por hectare, comparado com o fornecimento de metade da lâmina de irrigação requerida (L50); b) as gemas localizadas no segundo quarto do dossel da touceira tem maior capacidade de pegamento, bem como as próximas do ápice; c) a adoção de déficit hídrico na fase pré-colheita (estratégias de maturação) em condições de irrigação plena (L100) podem reduzir em média 11% o número de gemas viáveis por hectare; d) a produtividade da água para gemas de cana-de-açúcar (2,88 à 3,17 litros gema-1) não tem relação com a lâmina de irrigação ou a estratégia de maturação adotada, sendo influenciada somente pelo material genético utilizado (variedade); e) as estratégias de restrição do volume de água aplicado (L50, L75 e L125) oneram em até 51% os custos de produção para cada gema viável produzida, comparado à irrigação plena (L100). / Sugarcane crop is facing a difficult road ahead due the rising input and labor costs and the lack of innovative alternative technologies to boost productivity. Thus, it is essential not only increase the productivity of sugarcane, but also keep it in a sustainable way, had conserving limited resources throughout time. To accomplish this, there is a strong necessity to use alternative methods of production to boost sugarcane productivity on the principles of \'\'more with less\'\'. More than ever, the answer refers to proper planning, which includes among other practices, the formation of healthy nursery, with definable areas intended to multiplication of seedlings and the choice of the best options among the available materials for the formation of cane field. Sugarcane is cultivated using cuts of stalks or bud chips and this cultivation method is gradually becoming uneconomical due the cost of \"nurseries areas\" used for renew old areas, requiring more than 20 percent of the total production cost for renovation/new plantings. This work has the hypothesis that for sugarcane, there is a better combination of water depth / intensity of water stress and bud chip position along the stem, in order to maximize the fixation / development of buds. The objective is evaluate the effect of four irrigation levels, four water stress intensities in the maturation phase, four positions along the stem, for eight varieties of sugarcane submitted to drip irrigation, analyzing the related variables quality seedlings (productivity and cost of viable buds of sugarcane). The experiment was conducted in Piracicaba - SP, in the research area of the Department of Biosystems Engineering of the College of Agriculture \"Luiz de Queiroz\" (ESALQ / USP), in a protected environment (greenhouse). The experimental design was completely randomized blocks, with 3 complete blocks. The treatments were arranged in a factorial design (4x4x4x8), totaling 511 treatments and 1536 experimental plots. The treatments were: water depth during the cycle with 4 levels (Water depths); commercial variety of cane sugar, with 8 varieties (Variety), intensity of water deficit in the final phase of the maturation of sugarcane, 4 water restriction strategies (maturation); and bud chip position along the stem length, 4 position (position). Considering the conditions in which this study was developed: drip irrigation high frequency under full irrigation and irrigation deficit, it can be concluded that: a) The water depth that returned the total water required in high frequency (L100) promotes an average of 42% increase in total viable bud chips produced per hectare, compared with when it was supplied half of the required water depth (L50); b) Bud chips located in the second part of the canopy has a higher fixation capacity, as well as the buds located at the top; c) The adoption of water deficit in the pre-harvest phase (maturity strategies) in full irrigation conditions (L100) can reduce an average of 11% the number of viable buds per hectare; d) The water productivity of sugarcane bud chip (2,88 à 3,17 litros gema-1) has no relation to the water depth or adopted maturation strategy, being influenced by the used genetic material (variety); e) The restriction water strategies applied (L50, L75 and L125) can increase up to 51% of the costs for each viable bud produced compared to full irrigation (L100).
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Protótipo de cortadora-amontoadora: desempenho operacional e econômico em cana-de-açúcar (Saccharum spp.) com queima prévia. / Chopper-pile prototype: operational and economic performances in burned sugar cane (Saccharum spp.).Orsolini, José Mauricio 08 October 2002 (has links)
O presente trabalho teve por objetivo efetuar a análise dos Desempenhos Operacional e Econômico do protótipo de uma cortadora-amontoadora para cana-de-açúcar, comparado-os com valores obtidos na bibliografia e referentes ao corte manual realizado em cana-de-açúcar, com queima prévia e sugerir modificações no projeto mecânico do espécime. O protótipo analisado é apresentado como uma opção para a substituição da mão-de-obra responsável pelo corte dos canaviais. Para tanto foram utilizadas as metodologias propostas por Ripoli (1986) e Molina Jr. (2000). O protótipo em questão foi o Phoenix CM500i®, fabricado pela empresa Motocana® Ltda 2 . Os testes foram realizados na Usina Costa Pinto, localizada no município de Piracicaba, interior de São Paulo, durante o mês de julho de 2.000. Foram determinados os seguintes parâmetros: Capacidade Efetiva de Corte (média de 398,27kN.h -1 ou 40,61t.h -1 ); Eficácia de Manipulação (média de 93,84%); Perdas (média de 6,59%, de canas não colhidas e/ou suas frações remanescentes na soqueira); Matéria Estranha média de 3,75% e Custo estimado de R$0,194.kN -1 (ou R$1,90.t -1 ) na Capacidade Efetiva de Corte, o que, se comparado ao custo de R$0,306.kN -1 (ou R$3,00.t -1 ) do corte manual representa uma redução de 36,6% no custo da operação. Por se tratar de um protótipo, foram realizados, ainda, exercícios de projeção com base nas modificações sugeridas e referentes ao seu projeto mecânico. Estes estudos apresentaram novos valores estimados de Capacidade Efetiva de Corte de R$0,083.kN -1 (ou R$0,81.t -1 ) de cana cortada, ou seja, uma redução da ordem de 85% nos custos em relação aos custos da utilização da mão-de-obra para este mesmo fim. / The present study had the objective to analyze the Operational and Economic Performances of a chopper-pile prototype for sugar cane, comparing them with the found values in the bibliography and referring to the manual cut in burned sugar cane and suggest modifications on the machine mechanical project. The analyzed prototype is presented as a substitution option for the hand workers, which are responsible for the sugar cane cut. The methodologies that had been used in this study were proposed by Ripoli (1986) and Molina Jr. (2000). The prototype was the Phoenix CM500i®, manufactured by Motocana® Ltd 3 . The tests had been carried out in Costa Pinto Sugar Mill, located in Piracicaba county, São Paulo State, during the month of July 2.000. The following parameters had been determined: Cut Effective Capacity (average of 398,27kN.h -1 or 40,61t.h -1 ); Manipulation Effectiveness (93,84% average); Losses (6,59% average, not harvested sugar cane and/or its remaining fractions in the stubble); 3,75% of Strange Matter Harvested and a Estimated Cost of R$0,194.kN -1 (or R$1,90.ton -1 ) in the Cut Effective Capacity, which if compared with the R$0,306.kN -1 (or R$3,00.ton -1 ) manual cut cost represents a 36,6% cost reduction of the operation costs. Dealing with the prototype, projection's exercises had been made on the basis of the suggested modifications referring to in its mechanical project. These studies had presented Cut Effective Capacity estimated values of R$0,083.kN -1 (or R$0,81.ton -1 ) of cut sugar cane, a 85% cost reduction in relation with the use of hand workers for this same end.
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EFEITO DO EVENTO MON88017 (Cry3Bb1), DE INSETICIDA E DA ÉPOCA DE SEMEADURA NA REDUÇÃO DO DANO DE Diabrotica speciosa (GERMAR, 1824) (COLEOPTERA: CHRYSOMELIDAE) NA RAIZ DO MILHOGallo, Paulo 13 November 2012 (has links)
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Previous issue date: 2012-11-13 / The presence of Diabrotica speciosa larvae causes damage to corn root system and reduction in grain yield, mainly in second season crops. Applying insecticide in the seed furrow can be effective, but this assumes a form of preventive control and implies higher production costs and environmental impact. We evaluated the efficacy of genotypes AG7000RW and DKB330RW (Cry3Bb1) and their isolines to reduce the damage caused by D. speciosa larvae to corn root system, the efficacy of the insecticide fipronil applied in the furrow, and the effect of the interaction of both treatments on the yield of maize hybrids, as well as the planting date when
the most severe damage occurs. The efficacy experiment was carried out in Itaberá, SP, in no-till planting system after oat crop. The damage to the roots was evaluated 52 days after emergence, using a visual score according to its intensity.
Stalk lodging was determined by counting the plants leaning more than 25º in relation to its own axis at harvest. Genotypes AG7000 and DKB330 with no insecticide application presented damage and the resulting scores were 1.62 and
1.85, whereas the scores of their Bt isolines were 0.25 and 0.24, respectively. Genotypes AG7000 and AG700RW had the highest percentage of matter and amount of dry root in relation to DKB330 and DKB330RW, regardless of insecticide application. Stalk lodging of 46.7% found in non-Bt genotype DKB330 with no insecticide application reflected negatively on the yield of this treatment. In contrast, with insecticide application, stalk lodging ranged from 0.2% to 2.2%
between genotypes, not influencing their yield. Cry3Bb1 protein was effective in reducing the damage to the root regardless of the genotype tested. Genotypes with high yield potential and lower root mass may present higher yield response when protected by the toxin or insecticide in the presence of a large larval population. In the 2010/2011 season, we assessed the damage in non-Bt corn root
at four planting dates in Itaberá (10/14, 11/3, 11/25, and 12/20) and three in Castro, PR (9/29, 10/21, and 11/11). In the following season, 2011/2012, we evaluated six planting dates in Itaberá (9/21, 10/18, 11/21, 12/28, 1/30, and 2/20)
and four in Castro (9/20, 10/10, 10/30, and 11/20). We observed that, from the second planting date on, the root damage reached scores over 3.0 and remained above 4.0 in all other planting dates in Itaberá in both seasons. In Castro, only the seeding performed in 11/20/2011 reached a score above 3.0. The use of protection in corn root, by applying insecticide or toxin, presented a greater response in sowing carried out from October on in the region of Itaberá. / A presença de larva de Diabrotica speciosa danifica o sistema radicular do milho e causa redução na produtividade de grãos, principalmente nas lavouras de segunda safra. A aplicação de inseticida no sulco de semeadura pode ser eficaz, porém, esta forma de controle assume caráter preventivo e implica maior custo de produção e impacto ambiental. Avaliaram-se a eficácia dos genótipos AG7000RW e DKB330RW (Cry3Bb1) e de suas isolíneas na redução do dano da larva de D. speciosa na raiz do milho, a eficácia do inseticida fipronil aplicado no sulco de semeadura e o efeito da interação de ambos os tratamentos sobre a produtividade dos genóti os de milho, bem como a época de semeadura em que ocorre maior dano da larva. O experimento de eficácia foi instalado em Itaberá,
SP, na safra 2011/2012, sob sistema de plantio direto na palha após cultura de aveia. Os danos nas raízes foram avaliados aos 52 dias após a emergência, atribuindo-se nota visual de acordo com sua intensidade. O acamamento foi
determinado contando-se as plantas com inclinação maior que 25º em relação ao próprio eixo no momento da colheita. Os genótipos AG7000 e DKB330 sem inseticida apresentaram dano, e as notas resultantes foram 1,62 e 1,85, enquanto
as notas de suas isolíneas Bt foram 0,25 e 0,24, respectivamente. Os genótipos AG7000 e AG700RW obtiveram os maiores percentuais de matéria e quantidade de massa seca na raiz em relação a DKB330 e DKB330RW, independentemente da aplicação do inseticida. O acamamento de 46,7% encontrado para o genótipo DKB330 sem aplicação de inseticida refletiu negativamente na produtividade deste tratamento. Por outro lado, com a aplicação de inseticida, o acamamento variou de 0,2% a 2,2% entre os genótipos, não influenciando sua produtividade. A proteína Cry3Bb1 foi eficaz na redução dos danos na raiz independentemente do genótipo testado. Genótipos com alto potencial produtivo e com menor massa de raiz podem apresentar maior resposta de produtividade quando protegidos com a toxina ou o inseticida na presença de alta população de larvas. Na safra 2010/2011, avaliaram-se os danos na raiz do milho não Bt em quatro épocas de semeadura em Itaberá (14/10, 3/11, 25/11 e 20/12) e três em Castro, PR (29/9, 21/10 e 11/11). Na safra seguinte, de 2011/2012, avaliaram-se seis épocas em Itaberá (21/9, 18/10, 21/11, 28/12, 30/1 e 20/2) e quatro em Castro (20/9, 10/10, 30/10 e 20/11). Constatou-se que, a partir da segunda época, os danos na raiz atingiram nota superior a 3,0 e permaneceram acima de 4,0 em todas as demais épocas de semeadura em Itaberá, nas duas safras avaliadas. Em Castro, apenas a semeadura de 20/11/2011 atingiu nota superior a 3,0. A utilização da proteção na raiz do milho, pela utilização de inseticida ou toxina, apresentou maior resposta nas semeaduras realizadas a partir do mês de outubro na região de Itaberá.
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RESISTÊNCIA DE COLMO À PENETRAÇÃO COMO PREDITOR DA QUALIDADE DE COLMOS EM MILHO / RESISTÊNCIA DE COLMO À PENETRAÇÃO COMO PREDITOR DA QUALIDADE DE COLMOS EM MILHOOliveira, Rodrigo Martins de 22 December 2015 (has links)
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Previous issue date: 2015-12-22 / Annual losses of up to 25% of world corn production are stimated as a result of stalk lodging
and root lodging. The use of resistant hybrids is the main method of control, though only use
the visual evaluation is very limited. In this context, it is crucial to find methods to evaluate the
quality of stalks with high correlationship with stalk loding that could be effective to detect
level differences of resistance to stalk lodging. The objective of this study was to estimate the
correlationship between agronomic characteristics and attributes associated with stalk lodging of corn hybrids and their inbred lines. Additionally, select genotypes that simultaneously have the highest number of characteristics associated with stalk quality and grain yield by principal component analysis. There were performed four experiments using corn hybrids and one experiment with inbred lines for evaluation of corn stalk penetration resistance as predictor of corn stalk quality in the 2013/2014 season. The experimental design was a randomized block design with twelve treatments and four reps for experiments with hybrid and sixteen treatments and three reps for the experiment with inbred lines. The results of the hybrids and inbred lines experiments were submited to Pearson correlation analysis through the GENES statistical software, and principal component analysis was performad by the R sorftware 2.15.2. The physical stalk quality represented mainly by stalk lodging, root lodging and corn stalk penetration resistance proved to be limiting for the selection of superior corn genotypes,because corn stalk lodging affected negatively the grain yield in corn hybrids. The stalk penetration resistance evaluation in inbred lines showed a significant negative correlation of 60% with stalk lodging, which makes this evaluation suitable for use to select inbred lines with enhanced physical quality of the stalks, enabling the detection of differences in stalk lodging resistance levels from the inbred lines. Using the principal component analysis was possible the
identification of the corn inbred lines L2, L3, L6, L13 and L14, also the hybrids P30F53YH,30A37PW, DKB240PRO2 and H14 with the most favorable characteristics for stalk physical quality for corn grain yield. / Estima-se perdas anuais de até 25% na produção mundial de milho em consequência do acamamento e do quebramento do colmo. A utilização de híbridos resistentes é o principal
método de controle, embora utilizar apenas a avaliação visual seja bastante limitada. Dessa forma, é imprescindível encontrar metodologias para avaliar a qualidade dos colmos com alta
correlação com o quebramento de colmo à campo e que seja eficaz na detecção de diferenças nos níveis de resistência ao quebramento. O objetivo deste trabalho foi estimar as correlações entre características agronômicas e atributos associados ao quebramento de colmos de híbridos
e linhagens endogâmicas de milho. Adicionalmente, selecionar genótipos que reúnam simultaneamente o maior número de características associadas à qualidade de colmos e ao
rendimento de grãos através da análise de componentes principais. Foram realizados quatro experimentos de híbridos de milho e um de linhagens endogâmicas para avaliação da resistência dos colmos ao quebramento como preditor da qualidade de colmos em milho na safra 2013/2014. O delineamento experimental foi o de blocos ao acaso com doze tratamentos e quatro repetições para os experimentos com híbridos e dezesseis tratamentos e três repetições para o experimento com linhagens endogâmicas. Os dados dos experimentos de híbridos e de linhagens foram submetidos à análise de correlação de Pearson através do software estatístico
GENES, e a análise de componentes principais através do software R versão 2.15.2. A qualidade física dos colmos representada principalmente pelas características quebramento de colmo, acamamento e resistência do colmo à penetração demonstraram ser limitantes para a seleção de genótipos superiores de milho, pois o quebramento dos colmos nos híbridos de milho afetou negativamente o rendimento de grãos nos experimentos. A avaliação da resistência à penetração do colmo nas linhagens endogâmicas teve correlação significativa e negativa de 60% com o quebramento de colmo, o que a torna passível de utilização para a seleção de linhagens com maior qualidade física dos colmos, possibilitando a detecção de diferenças nos níveis de resistência ao quebramento dos colmos entre as linhagens endogâmicas. Através da análise de componentes principais foi possível a identificação das linhagens endogâmicas de milho L2, L3, L6, L13 e L14 e os híbridos P30F53YH, 30A37PW, DKB240PRO2 e H14 com o maior número de características favoráveis para qualidade física dos colmos e potencial para o rendimento de grãos.
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Protótipo de cortadora-amontoadora: desempenho operacional e econômico em cana-de-açúcar (Saccharum spp.) com queima prévia. / Chopper-pile prototype: operational and economic performances in burned sugar cane (Saccharum spp.).José Mauricio Orsolini 08 October 2002 (has links)
O presente trabalho teve por objetivo efetuar a análise dos Desempenhos Operacional e Econômico do protótipo de uma cortadora-amontoadora para cana-de-açúcar, comparado-os com valores obtidos na bibliografia e referentes ao corte manual realizado em cana-de-açúcar, com queima prévia e sugerir modificações no projeto mecânico do espécime. O protótipo analisado é apresentado como uma opção para a substituição da mão-de-obra responsável pelo corte dos canaviais. Para tanto foram utilizadas as metodologias propostas por Ripoli (1986) e Molina Jr. (2000). O protótipo em questão foi o Phoenix CM500i®, fabricado pela empresa Motocana® Ltda 2 . Os testes foram realizados na Usina Costa Pinto, localizada no município de Piracicaba, interior de São Paulo, durante o mês de julho de 2.000. Foram determinados os seguintes parâmetros: Capacidade Efetiva de Corte (média de 398,27kN.h -1 ou 40,61t.h -1 ); Eficácia de Manipulação (média de 93,84%); Perdas (média de 6,59%, de canas não colhidas e/ou suas frações remanescentes na soqueira); Matéria Estranha média de 3,75% e Custo estimado de R$0,194.kN -1 (ou R$1,90.t -1 ) na Capacidade Efetiva de Corte, o que, se comparado ao custo de R$0,306.kN -1 (ou R$3,00.t -1 ) do corte manual representa uma redução de 36,6% no custo da operação. Por se tratar de um protótipo, foram realizados, ainda, exercícios de projeção com base nas modificações sugeridas e referentes ao seu projeto mecânico. Estes estudos apresentaram novos valores estimados de Capacidade Efetiva de Corte de R$0,083.kN -1 (ou R$0,81.t -1 ) de cana cortada, ou seja, uma redução da ordem de 85% nos custos em relação aos custos da utilização da mão-de-obra para este mesmo fim. / The present study had the objective to analyze the Operational and Economic Performances of a chopper-pile prototype for sugar cane, comparing them with the found values in the bibliography and referring to the manual cut in burned sugar cane and suggest modifications on the machine mechanical project. The analyzed prototype is presented as a substitution option for the hand workers, which are responsible for the sugar cane cut. The methodologies that had been used in this study were proposed by Ripoli (1986) and Molina Jr. (2000). The prototype was the Phoenix CM500i®, manufactured by Motocana® Ltd 3 . The tests had been carried out in Costa Pinto Sugar Mill, located in Piracicaba county, São Paulo State, during the month of July 2.000. The following parameters had been determined: Cut Effective Capacity (average of 398,27kN.h -1 or 40,61t.h -1 ); Manipulation Effectiveness (93,84% average); Losses (6,59% average, not harvested sugar cane and/or its remaining fractions in the stubble); 3,75% of Strange Matter Harvested and a Estimated Cost of R$0,194.kN -1 (or R$1,90.ton -1 ) in the Cut Effective Capacity, which if compared with the R$0,306.kN -1 (or R$3,00.ton -1 ) manual cut cost represents a 36,6% cost reduction of the operation costs. Dealing with the prototype, projection's exercises had been made on the basis of the suggested modifications referring to in its mechanical project. These studies had presented Cut Effective Capacity estimated values of R$0,083.kN -1 (or R$0,81.ton -1 ) of cut sugar cane, a 85% cost reduction in relation with the use of hand workers for this same end.
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Biological productivity, soil resource use and stalk borer infestation in maize lablab planting date and density intercropping systemsMaluleke, Hanyeleni Mary January 2004 (has links)
Thesis (M.Sc. (Agriculture (Crop Science)) -- University of Limpopo, 2004. / Canon Collins Educational Trust of Southern Africa (CCETSA), and the National Research Foundation (NRF)
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Mutational Analysis of FERM Domain Proteins CG34347 and Cdep in DrosophilaMilic, Milos 02 August 2012 (has links)
Crumbs is a transmembrane protein and apical determinant in Drosophila epithelial cells. Its cytoplasmic tail contains a PDZ and a FERM domain-binding site through which Crumbs interacts with the FERM proteins Yurt, Moesin and Expanded. Recent evidence suggests that Crumbs can also interact with the uncharacterised FERM proteins CG34347 and Cdep. The main objective of my thesis was to generate mutations in CG34347 and Cdep to facilitate the functional analysis of these genes.
I generated a mutation for Cdep that remains to be characterised and two mutant lines for CG34347; one lacking the first exon and one lacking the entire gene, using a FRT-based recombination strategy. Both CG34347 mutants cause severe ovarian defects. The most consistent defect is a multilayering of the interfollicular stalk. These defects are also observed when Notch, Hippo, Wingless and Hedgehog signalling pathways are overactive in ovaries suggesting that CG34347 participates in one of those pathways.
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Mutational Analysis of FERM Domain Proteins CG34347 and Cdep in DrosophilaMilic, Milos 02 August 2012 (has links)
Crumbs is a transmembrane protein and apical determinant in Drosophila epithelial cells. Its cytoplasmic tail contains a PDZ and a FERM domain-binding site through which Crumbs interacts with the FERM proteins Yurt, Moesin and Expanded. Recent evidence suggests that Crumbs can also interact with the uncharacterised FERM proteins CG34347 and Cdep. The main objective of my thesis was to generate mutations in CG34347 and Cdep to facilitate the functional analysis of these genes.
I generated a mutation for Cdep that remains to be characterised and two mutant lines for CG34347; one lacking the first exon and one lacking the entire gene, using a FRT-based recombination strategy. Both CG34347 mutants cause severe ovarian defects. The most consistent defect is a multilayering of the interfollicular stalk. These defects are also observed when Notch, Hippo, Wingless and Hedgehog signalling pathways are overactive in ovaries suggesting that CG34347 participates in one of those pathways.
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Κυτταρική ανάλυση των ιντεγκρινικών συνδέσεων στη Drosophila melanogasterΨαρρά, Ελένη 18 December 2013 (has links)
Η διδακτορική μου διατριβή εστιάζει στη λειτουργική ανάλυση του μοριακού μηχανισμού λειτουργίας της ιντεγκρινο-συνδεόμενης κινάσης (ILK) κατά την ανάπτυξη στη Drosophila. Έγινε διερεύνηση: α) της λειτουργικής συντήρησης της ILK κατά την εξέλιξη, β) του πιθανού ρόλου συγκεκριμένων αμινοξικών μοτίβων στον κυτταρικό εντοπισμό και τη λειτουργία της πρωτεΐνης και γ) των λειτουργικών ιδιοτήτων της ILK όταν είναι ομοιοπολικά συζευγμένη στην πλασματική μεμβράνη. Παράλληλα, αναζητήσαμε νέους λειτουργικούς ρόλους της ILK κατά την ανάπτυξη: α) σε άλλους ιστούς εκτός από το μυϊκό σύστημα και β) στην ωογένεση.
Η ILK στο επίπεδο της αμινοξικής αλληλουχίας παρουσιάζει 60% ταυτότητα και 75% ομολογία με την αντίστοιχη πρωτεΐνη των θηλαστικών. Με βάση αυτή την ομολογία, ελέγξαμε την πιθανή φυλογενετική συντήρηση της λειτουργίας της ILK. Για το σκοπό αυτό κατασκευάστηκαν διαγονιδιακά στελέχη που περιείχαν την κωδική περιοχή της ILK του ανθρώπου (hILK) και του ποντικού (mILK) αντίστοιχα. Η ILK του ποντικού και του ανθρώπου ακολουθεί παραπλήσιο πρότυπο υποκυτταρικής κατανομής με την ενδογενή πρωτεΐνη στα μυϊκά κύτταρα Drosophila. Οι δυο ετερόλογες πρωτεΐνες υποκαθιστούν τη λειτουργία της ILK στη Drosophila. Ωστόσο, η ILK του ανθρώπου παρουσιάζει μειωμένη δυνατότητα πρόσδεσης με την parvin της Drosophila.
Προκειμένου να διερευνήσουμε το μοριακό μηχανισμό ρύθμισης και δράσης της ILK κατά την ανάπτυξη, ελέγξαμε εάν η φωσφορυλίωση των αμινοξέων S176 και T180 υπεισέρχεται στη ρύθμιση της λειτουργίας της ILK. Σε πειράματα κυτταρικών σειρών έχει δειχθεί ότι στις θέσεις αυτές η φωσφορυλίωση ελέγχει την υποκυτταρική κατανομή της πρωτεΐνης στον πυρήνα. Ωστόσο, αποδείξαμε ότι η πιθανή φωσφορυλίωση στις ισχυρά συντηρημένες θέσεις S176 και T180 δεν είναι απαραίτητη για τον εντοπισμό της ILK στις μυοτενοντικές συνδέσεις και τη λειτουργία της ILK.
Ένα άλλο αμινοξικό κατάλοιπο που είναι απαραίτητο για τον εντοπισμό της ILK στις εστιακές θέσεις προσκόλλησης είναι το F436, το οποίο εδράζεται στην τελευταία α έλικα του καρβοξυτελικού λοβού της περιοχής κινάσης. Ο υποκυτταρικός εντοπισμός της ILK και η λειτουργία της δεν επηρεάζονται από τη σημειακή μεταλλαγή F436Α σε αντίθεση με πειράματα σε κυτταρικά μοντέλα. Η σημειακή μεταλλαγή F436A αποδυναμώνει την ικανότητα αλληλεπίδρασης της ILK με την parvin.
Εξετάσαμε αν η μεμβρανοδεσμευόμενη ILK μέσω παλμυτυλίωσης ή φαρνεσυλίωσης μπορεί να υποκαταστήσει την απουσία της ενδογενούς, καθώς και εάν μπορεί να προσελκύσει πρωτεΐνες του συνδεοσώματος ανεξάρτητα των ιντεγκρινών. Κατασκευάστηκαν δυο εναλλακτικές μορφές μεμβρανοδεσμευμένης ILK, οι GAP-ILK-GFP και ILK-GFP-HRAS εντοπίζονται με επιτυχία σταθερά στην πλασματική μεμβράνη των εμβρυϊκών μυϊκών κυττάρων. Επίσης, οι GAP-ILK-GFP και ILK-GFP-HRAS υποκαθιστούν πλήρως την ενδογενή ILK σε όλα τα αναπτυξιακά στάδια της ζωής της μύγας. Τέλος, η GAP-ILK-GFP συγκεντρώνει στις ΜΤΣ τα άλλα δυο μέλη του IPP συμπλόκου αλλά και την talin στις ΜΤΣ εμβρύων τελικού σταδίου τόσο αγρίου τύπου όσο και ομοζυγώτων για aPS2.
Παράλληλα, μελετήσαμε , τόσο σε γενετικό όσο και σε μοριακό επίπεδο, το ρόλο της ILK στη μορφογένεση του ωοθυλακίου, την οργάνωση και ομοιόσταση του θυλακώδους επιθηλίου κατά τη διάρκεια της ωογένεσης στη Drosophila. Αποσιωπήσαμε την ilk κατασκευάζοντας γενετικά μωσαϊκά αλλά και ιστοειδικά διασωσμένα άτομα. Παρατηρήσαμε ότι η ILK είναι απαραίτητη για τη διαδικασία της ωογένεσης στη μύγα. Η απουσία της ILK προκαλεί διαταραχές στο σχηματισμό των διαθυλιακών μίσχων και ανωμαλία στο διαχωρισμό των νεοσχηματιζόμενων διαδοχικών ωοθυλακίων (σιαμαία ωοθυλάκια).
Επίσης, τα πειράματά μας αποκάλυψαν ότι η ILK είναι απαραίτητη για την οργάνωση των ινιδίων ακτίνης κατά τα τελευταία στάδια της ωογένεσης και για την ομοιόσταση του κυτταροσκελετού ακτίνης κατά τον ακραιο-βασικό άξονα του κυττάρου. Ακόμη, η ILK είναι απαραίτητη για την οργάνωση και διατήρηση των βασο-πλευρικών κυτταρικών συνδέσεων στα θυλακιοκύτταρα, αλλά όχι των συνδέσεων ζώνης. Η απουσία της ILK διαταράσσει τον εντοπισμό των ιντεγκρινών στα άκρα των ινιδίων τάσης της ακτίνης στα θυλακιοκύτταρα των τελευταίων σταδίων. Επιπλέον, η ILK συμμετέχει στη ρύθμιση της δυναμικής της F-ακτίνης μειορρυθμίζοντας το Dia και αυξορρυθμίζοντας την profilin. H ILK εμπλέκεται στον έλεγχο της συσταλτότητας των ινιδίων ακτο-μυοσίνης στα θυλακιοκύτταρα των τελευταίων σταδίων, πιθανότατα μέσω της διαταραχής στον υποκυτταρικό εντοπισμό του RhoI, καθώς και μέσω της εκτοπικής συσσώρευσης της μυοσίνης (zipper).
Τέλος, η ilk αλληλεπιδρά γενετικά με τη dpak στο επιθήλιο του ωοθυλακίου. Η ΙLK επηρεάζει τον εντοπισμό της dPAK στα θυλακιοκύτταρα τελευταίων σταδίων. Επίσης, η dPAK είναι απαραίτητη για τον εντοπισμό των ιντεγκρινών και της ILK στα άκρα των ινιδίων τάσης της ακτίνης. Ενώ, η απουσία της dpak, όπως και της ilk, διαταράσσoυν την οργάνωση και των ινιδίων τάσης της ακτίνης σε θυλακιοκύτταρα τελευταίων σταδίων. / My thesis is focused on the functional analysis of the molecular mechanism of the
integrin-linked kinase (ILK) during development in Drosophila. We studied: a) the
functional conservation of ILK in evolution, b) the possible role of specific amino
acid motifs in the subcellular localization and function of ILK and c) the functional
properties of ILK, when covalently bound to the plasma membrane. Furthermore, we
sought new functional roles for ILK during development: a) in other tissues besides
muscle system and b) in oogenesis.
ILK protein sequence shares 60% identity and 75% similarity with the
mammalian ILK. Based on these data, we tested the possible phylogenetic
conservation of ILK function. For this purpose, we generated transgenic lines carrying
the coding sequence of either human ILK (hILK) or mouse ILK (mILK). The
mammalian ILK has localizes similarly to the endogenous protein, in the muscle cells
of Drosophila. Both mammalian proteins can substitute for the ILK function in
Drosophila. However, human ILK binds to Dparvin with reduced affinity compared
to the fly ILK.
In order to investigate the molecular mechanism through which ILK regulates
and acts during development, we tested whether the phosphorylation on the amino
acids S176 and T180 contributes to the regulation of ILK function. It has been shown,
in cell culture models, that the phosphorylation on these sites controls the subcellular
localization of the protein in the nucleus. However, we proved that the possible
pgoshorylation of these highly conserved residues is dispensable for the ILK
localization at the muscle attachment sites (MAS) as well as for the function of ILK.
Another residue which is necessary to localise ILK at the focal adhesion sites
is F436. It is located on the last a helix of the carboxyl-terminal lobe of the kinase-like
domain. The subcellular localization and the ILK function are unaffected by the point
mutation F436A, in contrast to the experimental data on cell culture models. The
point mutation F436A affects the ability of ILK to bind to parvin.
We examined, whether membrane-bound ILK, through palmytoylation or
farnesylation, is able to substitute the absence of the endogenous ILK, if ii can recruit
proteins of the adhesome, independently of integrins. We generated two alternative
forms of membrane-bound ILK, GAP-ILK-GFP and ILK-GFP-HRAS, which both localize successfully at the plasma membrane of the embryonic muscle cells. Also,
GAP-ILK-GFP and ILK-GFP-HRAS can substitute for the endogenous ILK
throughout development. Moreover, GAP-ILK-GFP is able to recruit both PINCH and
Parvin, as well as talin at the MAS, in both wild type and aPS2 mutant embryonic
muscle cells.
Furthermore, we studied, in genetic molecular level, the role of ILK in the
morphogenesis of the egg chambers, the organization and the homeostasis during
oogenesis in Drosophila. We used two experimental approaches in order to silence
ilk: a) we generated genetic mosaics for ilk and b) we used conditionally rescued ilk-/-
flies. We observed that ILK is indispensable for the process of oogenesis in the fly.
Loss of ILK disrupts the stalk cell formation and the separation of the successive
newly formed egg chambers (twin egg chambers).
Also, our experiments revealed that ILK is essential for the organization of the
actin stress fibers at the late developmental stages of oogenesis and for the
homeostasis of the actin cytoskeleton along apico-basal axis of the cell. ILK is
indispensable for the organization and the maintenance of the baso-lateral cell
junctions in the follicle cells, but not for the adherens junctions. Loss of ILK disrupts
the localization of integrins at the tips of the actin stress fibers of the follicle cells at
late developmental stages. Moreover, ILK participates in the regulation of the F-actin
dynamics by down-regulating Dia and up-regulating profilin. ILK is involved in the
control of the contractility of the acto-myosin fibers in the follicle cells at late
developmental stages, probably by affecting the subcellular localization of Rho1, and
causing ectopic accumulation of myosin (zipper).
Finally, ilk interacts genetically with dpak in the follicular epithelium. ILK affects
dPAK localization in the follicle cells at late developmental stages. Furthermore,
dPAK is essential for the localization of both integrins and ILK at the tips of actin
stress fibers. Loss of dpak, similarly to ilk, disrupts the organization of actin stress
fibers in follicle cells at late developmental stages.
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