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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.
151

A homoeopathic drug proving of the plant Peucedanum galbanum, analysing symptomatology in relation to the doctrine of signatures

Wagner, Abbey January 2007 (has links)
Mini-dissertation submitted in partial compliance with the requirements for the Master's Degree in Technology: Homoeopathy, Durban University of Technology, 2007. / The first objective of this study was to determine the symptomatology that the plant remedy Peucedanum galbanum 30CH, produced in healthy individuals, so that it could be prescribed according to the Law of Similars, as required by homoeopathy. The second objective was to analyse this symptomatology in relation to the doctrine of signatures. It was hypothesised that Peucedanum galbanum 30CH would produce symptomatology in healthy individuals which would correlate to the doctrine of signatures of the plant. / M
152

Assessment of the anaerobic baffled reactor for treatment of vegetable oil effluent

Frost, Lee-Anne January 2001 (has links)
Dissertation submitted in compliance with the requirements for the Master's Degree in Technology: Biotechnology, Technikon Natal, 2001. / The vegetable oil industry produces effluent containing quantities of fat, oil, sodium, phosphates as well as other pollutants. Oils and greases tend to clog sewers and pumps, thus creating difficulties within the municipal wastewater treatment works. Physico-chemical treatment methods, such as (Dissolved Air Flotation) OAF, gravity separation and the use of coagulants have been attempted providing a considerable reduction in organic loading; however, discharge standards are still not met. Thus, biological treatment methods are being sought after. Aerobic treatment has been attempted however, shock loads cause problems while running such a process. The objective of this study was to assess the efficiency of anaerobic digestion to degrade Vegetable Oil Effluent (VOE) as well as the efficiency of the Anaerobic Baffled Reactor (ABR). Anaerobic digestion involves the breakdown of organic matter by the action of microorganisms in the absence of oxygen, producing methane-rich biogas. The VOE was characterized, providing significant information on its chemical composition. It was found that the effluent had high sulphate content as well as a high COD content. High sulpahte content of wastewaters have known to promote growth of Sulphate Reducing Bacteria (SRB), which utilize the same energy source as Methane Producing Bacteria (MPB) and therefore compete for the same energy source. Sulphate and lipid reduction pretreatment experiments were carried out, using barium chloride and gravitational separation respectively. The results obtained, showed that the use of barium chloride to reduce sulphate content in VOE was successful, with significant sulphate reduction. The lipid reduction experiments however, did not show any significant lipid reduction. Batch tests were conducted in serum bottles to assess the extent of biodegradation of the VOE in its raw state as well as with reduced sulpahte content. Methanogenic toxicity tests on the raw and pretreated VOE provided a range of toxicity results. These assays are relatively simple and inexpensive. Gas production was monitored to determine the rate and extent of biodegradation. The efficiency of digestion was assessed by COD reduction. Results indicated potential inhibition of the methanogenic bacteria responsible for methane production by the / M
153

Dialelo parcial circulante interpopulacional em milho (Zea mays L.): efeito do número(s) de cruzamentos. / Circulant partial diallel in an interpopulation of maize: efect of the number (s) of crosses.

Fuzatto, Sandro Ricardo 15 April 2003 (has links)
No esquema de cruzamentos do dialelo parcial circulante interpopulacional (DPCI) cada linhagem da população é cruzada com s linhagens da população contrastante. O objetivo deste trabalho foi estudar o efeito do número s nas estimativas de capacidade geral de combinação (CGC) e capacidade especifica de combinação (CEC) de linhagens S1 para duas populações contrastantes (GN-03 e GN-04) de milho (Zea mays L.). Dois dialelos (DPCI A e DPCI B) com 50 linhagens cada, foram cruzadas (GN-03 x GN-04) usando s=6, de acordo com o esquema circulante de cruzamento. Dos 300 híbridos possíveis de cada dialelo, foram obtidos 297 no DPCI (A) e 282 no DPCI B. Os híbridos foram avaliados em três locais (Piracicaba-SP e Uberlândia-MG, com três repetições; e em Jataí-GO com duas repetições); o DPCI B foi avaliado somente nos dois primeiros locais. Os híbridos foram divididos em seis experimentos para cada DPCI. As análises foram realizadas para cada experimento e agrupadas posteriormente; os caracteres analisados foram peso de espigas (t/ha) e altura de planta (cm). As análises do DPCI foram realizadas para diferentes tamanhos de s, a saber, s=3, 4, 5, e 6. A produtividade média dos híbridos S1 x S1 nos dois grupos variou de 94% a 99% em relação à média das testemunhas em Uberlândia e Piracicaba. Na época safrinha avaliada em Jataí, a média dos híbridos foi 17% superior a média da testemunha. A fonte de variação CEC não mostrou significância em todos locais e caracteres avaliados. Em alguns casos a perda de graus de liberdade para a fonte de variação CEC com a redução de s, diminuiu o poder do teste de F. A redução de s levou a uma maior variação das estimativas de CGC e também a uma diminuição na precisão das estimativas de CEC. Os coeficientes de correlação (r) entre os valores obtidos pelo modelo reduzido ( j i ij gˆ + gˆ + ˆ = Y ˆ m ) com os observados ( ij ij j i ij e + s + g + g + = Y m ) foram calculados para ambos os dialelos em todos os locais. Os maiores coeficientes de correlação foram observados com os menores valores de s, induzindo à falsa interpretação de que as estimativas de CEC têm pouca influência na média do híbrido.Resultados consistentes foram obtidos quando utilizou-se o mínimo de cinco cruzamentos por parental (s=5), pois pode-se obter estimativas significativas e adequadas de CGC e CEC. As estimativas de componentes de variância ao nível interpopulacional foram estimados para o caráter peso de espigas, usando s=6 . As estimativas de variância aditiva expressas em (g/planta)2 foram 120,56, 61,92 e 38,44 para os locais Piracicaba, Uberlândia e Jataí, respectivamente. A variância de dominância foi superior a variância aditiva ao nível interpopulacional em todos os locais. As relações encontradas foram 6,05, 4,30 e 7,15 para os locais Piracicaba, Uberlândia e Jataí, respectivamente evidenciando a importância dos efeitos não aditivos entre as populações. / In the partial mating scheme, each line of one population is crosses with a number (s) of lines of the opposite population. The objective of this work was to study the effect of the number s in the estimates of general combining ability (GCA) and specific combining ability (SCA) of S1 lines from two contrasting populations (GN-03 and GN-04) of maize (Zea mays L.) crossed according to the partial diallel. Two groups (GA and GB) of fifth S1 lines were randomly crossed (GN-03 x GN-04) using s=6. From the 300 possible crosses in each group, some were last resulting 297 in GA and 282 in GB. Crosses were evaluated in three locations (Piracicaba-SP and Uberlandia-MG with three replications; and Jatai-GO with two replications); group GB was evaluated only in the first two locations. The whole set of crosses was divided into six experiments for each group. The analyses of variance were performed for each experiment and then grouped over experiments. The traits ear yield (t/ha) and plant height (cm) were analysed. The analyses were performed for varying number of crosses per line; i.e., for s=3, 4, 5, 6. Ear yield of S1 xS1 crosses in both groups varied from 94% to 99% in relation to the mean of both checks in Uberlandia and Piracicaba. In Jatai, only group GA in midseason planting yielded 17% more than the average of checks. Specific combining ability didn’t showed significance for every traits and locations. While general combining ability was always significant. Decreasing s led to a higher variation in the estimates of GCA and also to a decrease in the precision of SCA estimates. The coefficient of correlation between observed means ( ij ij j i ij e + s + g + g + = Y m ) and predicted means through the reduced model ( j i ij gˆ + gˆ + ˆ = Y ˆ m ) was calculated for boths groups in all locations. The higher coefficients of correlations were observed for smaller s values, leading to a miss interpretation. That SCA is of low importance in the phenotypic expression. Consistent results were observed by using s=5 allowing the detection of significance and good of the estimates of GCA and SCA. The estimates of the interpopulation variance components were obtained for ear yield using s=6. The estimates of the additive genetic variance expressed in (g/plant)2 were 120.56, 61.92 and 38.44 in Piracicaba, Uberlandia and Jatai, respectively. The dominance variance were higher than the additive variance in all locations; the ratios ) / ( 2 A 2 D s s were 6.1, 4.3 and 7.2, respectively, indicating the importance of the non additive effects in the interpopulation.
154

Enzimas do metabolismo de frutanos em Vernonia herbacea (VELL.) Rusby. / Fructan metabolizing enzymes in Vernonia herbacea (VELL.) Rusby.

Asega, Amanda Francine 14 April 2003 (has links)
A ocorrência de frutanos em espécies de Asteraceae foi amplamente documentada para a flora da região de cerrado da Reserva Biológica e Estação Experimental de Moji Guaçu. Dentre estas espécies destaca-se Vernonia herbacea, uma planta perene que apresenta órgãos subterrâneos de reserva, denominados rizóforos, que acumulam altos teores de frutanos do tipo inulina. Seu crescimento sazonal é caracterizado pela brotação das gemas existentes nos rizóforos, na primavera, seguida de floração e crescimento vegetativo intenso no verão e dormência no inverno. O conteúdo de frutanos diminui durante a brotação e floração, pois este carboidrato parece ser utilizado para a regeneração dos ramos aéreos que ocorre nesta fase. Estudos preliminares mostraram que a FEH, responsável pela mobilização dos frutanos, apresenta atividade elevada apenas durante a brotação; a despolimerização dos frutanos nos rizóforos de V. herbacea nesta fase foi evidenciada pelo aumento de açúcar redutor, especialmente frutose. O presente estudo teve como objetivo principal a análise da atividade das enzimas envolvidas no metabolismo de frutanos e análise do conteúdo e da composição de frutanos em rizóforos de V. herbacea induzidas à brotação. A brotação foi induzida pela remoção dos ramos aéreos e as atividades das enzimas FEH , SST, FFT e INV foram determinadas a cada quatro dias durante um mês após a poda. Um aumento na atividade da FEH foi observado entre os dias 13 e 20 após a poda, o que coincidiu com o início da brotação dos novos ramos que ocorreu no 13º dia. Este resultado sugere que a despolimerização de frutanos e a brotação são processos concomitantes em V. herbacea, que ocorrem naturalmente durante o ciclo fenológico, mas que também podem ser induzidos em outras fases do ciclo fenológico pela remoção dos ramos aéreos. A FFT parece atuar junto à FEH na diminuição do tamanho das cadeias de frutanos durante a rebrota, enquanto a SST é inibida devido, possivelmente, à interrupção do fornecimento de sacarose aos rizóforos pelos órgãos aéreos. Para a caracterização e purificação parcial da FEH de rizóforos de V. herbacea foram utilizados rizóforos de plantas induzidas à brotação através da remoção dos ramos aéreos. O extrato bruto apresentou, para atividade de FEH, pH ótimo de 4,5, temperatura ótima em 30 ºC e curva sigmoidal de concentração de substrato, sugerindo tratar-se de uma enzima alostérica. Esta enzima também apresentou maior especificidade por ligações do tipo b-2,1 do que sobre ligações b-2,6, e maior afinidade por frutanos de cadeias curtas quando comparadas com frutanos de cadeias longas. Utilizando precipitação com sulfato de amônia, cromatografia de afinidade e cromatografias de troca aniônica e catiônica, quatro frações com atividade de FEH foram purificadas. Destas quatro frações, duas foram submetidas à cromatografia de exclusão molecular, sendo que os pesos moleculares estimados para uma delas foi de 21 kDa e para outra, esta medida situou-se entre 155 e 39 kDa, devido à ampla faixa de exclusão da coluna utilizada. Os pesos moleculares das outras duas frações foram estimados por SDS-PAGE, sendo que as bandas visualizadas corresponderam a 81,3 e 57,5 kDa para uma e 57,5 kDa para a outra fração. / The occurrence of fructans has been reported in native species of a cerrado area of Reserva Biológica e Estação Experimental de Moji Guaçu. Vernonia herbacea, one of these species, presents underground organs named rhizophores which accumulate fructans of the inulin type as reserve carbohydrate. The seasonal growth pattern exhibited by plants of V. herbacea includes sprouting of buds from the rhizophores in spring, followed by a period of flower development and vegetative growth in summer, and dormancy in winter. The fructan content decreases during sprouting and flowering due to mobilization of this carbohydrate during the regeneration of the new shoots. Preliminary studies showed that FEH, the enzyme responsible for the mobilization of fructan, shows high activity only during sprouting. Fructan mobilization was detected by the increase in the amount of reducing sugar released, namely fructose. The aim of this work was to analyze the activities of the enzymes of fructan metabolism, FEH, SST, FFT and invertase and the fructan contents in rhizophores of plants induced to sprouting by defoliation. The enzyme activities were measured every 4 th day for a month after defoliation. Sprouting of new shoots started around the 13 th day, while an increase in FEH activity was detected between 13 and 20 days after defoliation. The results suggest that fructan depolimerization and sprouting are concomitant processes in V. herbacea that occur naturally during the phenological cycle; however, these processes can also be induced by defoliation during other stages of the phenological cycle. FFT seems to act together with FEH by catalyzing the decrease in fructan chain size during shoot regrowth, while SST was inhibited, possibly, due to interruption of sucrose supply to rhizophores from the aerial organs. The characterization and partial purification of FEH were done using rhizophores from plants which were induced to sprouting by defoliation. The optimal pH and temperature for FEH activity were pH4,5 and 30ºC, respectively. The substrate concentration curve exhibited a sigmoid shape, suggesting that FEH of V. herbacea is an alosteric enzyme. Additionally, this enzyme shows more specificity to b-2,1 than to b-2,6 linked fructan and higher affinity for short chain when compared to long chain fructans. Four fractions presenting FEH activity were partially purified by a combination of ammonium sulfate precipitation, affinity chromatography, and anion and cation exchange chromatographies. Two of these were submitted to size exclusion chromatography and the apparent molecular size for one of them was 21 kDa and for the other it was estimated to be between 39 and 155 kDa, due to the wide exclusion limit of the column used. The molecular size of the next two fractions were estimated by SDS- PAGE and the visualized bands corresponded to 81.3 and 57.5 kDa for the first fraction and to 57.5 kDa for the second one.
155

Avaliação de cultivares de feijão (Phaseolus vulgaris L.) para o sistema orgânico de produção / Evaluation of cultivars of beans (Phaseolus vulgaris L.) to the organic management of production

Araujo, Jacqueline Camolese de 11 August 2008 (has links)
Com o objetivo de avaliar as características, as produções e os comportamentos das diferentes cultivares de feijão de inverno irrigado em sistema de produção orgânico, conduziu-se um experimento na área experimental pertencente à Escola Superior de Agricultura \"Luiz de Queiroz/Universidade de São Paulo, localizada na Fazenda Areão e no núcleo experimental do Grupo de Agricultura Orgânica Amaranthus. Os seguintes parâmetros foram avaliados: a produtividade, número de flores por planta, número de vagens por planta, número de grãos por vagem, o índice de área foliar bem como o teor de nutrientes para cada variedade. As variedades analisadas foram do Grupo Carioca: BRS-Pérola, BRS-Aporé, IAC- Votuporanga e IPR- Juriti, e do Grupo Preto: IAC-Tunã e BRS-Valente. De acordo com o que foi analisado, os resultados permitem concluir que: (i) não houve diferença estatística entre os tratamentos, (ii) todas as cultivares avaliadas apresentaram ótimo desempenho sob manejo orgânico. / The goals of this study were to evaluate the characteristics, productivities and behaviors of different cultivars of common bean in an irrigate organic management system in the winter. The experiment was carried out at the experimental area of the Group of Organic Agriculture Amaranthus from Escola Superior de Agricultura \"Luiz de Queiroz\"/University of São Paulo, in Fazenda Areão, in Piracicaba, São Paulo State, Brazil. The following agronomic parameters related to common bean crop were used for statistical analysis: grain yield, number of flowers per plant, number of pods per plant and grains per pod, leaf area index, as well as leaf nutrient content for each cultivar. It were tested the following varieties from Carioca Group: BRS-Pérola, BRS-Aporé, IACVotuporanga and IPR- Juriti, and from Black Group: IAC-Tunã and BRS-Valente. The results showed that: (i) there were no statistical differences between the treatments, (ii) all the tested varieties had great productivity under organic management system.
156

Performances and kinetic studies of hydrotreating of bio-oils in microreactor

Attanatho, Lalita 17 September 2013 (has links)
Hydrotreating reaction of vegetable oil is an alternative method for the production of renewable biodiesel fuel. This reaction involves conversion of triglycerides into normal alkanes, leads to a deoxygenated and stable product, which is fully compatible with petroleum derived diesel fuel. The hydrotreating process uses hydrogen to remove oxygen from triglyceride molecules at elevated temperature in the presence of a solid catalyst. This work focused on the development of microtechnology-based chemical reaction process for liquid biofuel production from oil-based biofuel feedstock. A hydrotreating reaction of oleic acid and triolein as model compounds and jatropha oil as real feedstock was studied in a continuous flow microchannel reactor of inner diameter 500 ��m and of varied length; 1.5 - 5 m. The microchannel reactor was fabricated from SS-316. The walls of the microreactor were coated with a thin Al���O��� film, which was then impregnated with Ni-Mo catalyst containing phosphorus as promoter. The reactions were carried out in the temperature range of 275-325 ��C, residence time in the range of 11-40 s and at constant system pressure of 500 psig. The results showed that the microchannel reactor was suitable for the hydrotreating process. Complete conversion of the fatty acid hydrotreating reaction was achieved at a reaction temperature of 325 ��C. Hydrotreating of fatty acids occurred primarily via hydrodeoxygenation and the main liquid products were octadecane and heptadecane. Fatty alcohol, fatty acid and long chain esters were formed as reaction intermediates. Hydrotreating of triglycerides proceeded via the hydrocracking of triglycerides into diglycerides, monoglycerides and fatty acids. Then fatty acids were subsequently deoxygenated to hydrocarbons. The conversion of fatty acids and triglycerides increased with increasing temperatures. A detailed mathematical model was developed to represent this two-phase chemical reaction process. The mathematical model was entirely based on first principles, i.e. no adjustable or correlation parameters were used. Kinetic parameter estimation was performed and the predicted results were in good agreement with experimental results. / Graduation date: 2013 / Access restricted to the OSU Community, at author's request, from Sept. 17, 2012 - Sept. 17, 2013
157

Enzimas do metabolismo de frutanos em Vernonia herbacea (VELL.) Rusby. / Fructan metabolizing enzymes in Vernonia herbacea (VELL.) Rusby.

Amanda Francine Asega 14 April 2003 (has links)
A ocorrência de frutanos em espécies de Asteraceae foi amplamente documentada para a flora da região de cerrado da Reserva Biológica e Estação Experimental de Moji Guaçu. Dentre estas espécies destaca-se Vernonia herbacea, uma planta perene que apresenta órgãos subterrâneos de reserva, denominados rizóforos, que acumulam altos teores de frutanos do tipo inulina. Seu crescimento sazonal é caracterizado pela brotação das gemas existentes nos rizóforos, na primavera, seguida de floração e crescimento vegetativo intenso no verão e dormência no inverno. O conteúdo de frutanos diminui durante a brotação e floração, pois este carboidrato parece ser utilizado para a regeneração dos ramos aéreos que ocorre nesta fase. Estudos preliminares mostraram que a FEH, responsável pela mobilização dos frutanos, apresenta atividade elevada apenas durante a brotação; a despolimerização dos frutanos nos rizóforos de V. herbacea nesta fase foi evidenciada pelo aumento de açúcar redutor, especialmente frutose. O presente estudo teve como objetivo principal a análise da atividade das enzimas envolvidas no metabolismo de frutanos e análise do conteúdo e da composição de frutanos em rizóforos de V. herbacea induzidas à brotação. A brotação foi induzida pela remoção dos ramos aéreos e as atividades das enzimas FEH , SST, FFT e INV foram determinadas a cada quatro dias durante um mês após a poda. Um aumento na atividade da FEH foi observado entre os dias 13 e 20 após a poda, o que coincidiu com o início da brotação dos novos ramos que ocorreu no 13º dia. Este resultado sugere que a despolimerização de frutanos e a brotação são processos concomitantes em V. herbacea, que ocorrem naturalmente durante o ciclo fenológico, mas que também podem ser induzidos em outras fases do ciclo fenológico pela remoção dos ramos aéreos. A FFT parece atuar junto à FEH na diminuição do tamanho das cadeias de frutanos durante a rebrota, enquanto a SST é inibida devido, possivelmente, à interrupção do fornecimento de sacarose aos rizóforos pelos órgãos aéreos. Para a caracterização e purificação parcial da FEH de rizóforos de V. herbacea foram utilizados rizóforos de plantas induzidas à brotação através da remoção dos ramos aéreos. O extrato bruto apresentou, para atividade de FEH, pH ótimo de 4,5, temperatura ótima em 30 ºC e curva sigmoidal de concentração de substrato, sugerindo tratar-se de uma enzima alostérica. Esta enzima também apresentou maior especificidade por ligações do tipo b-2,1 do que sobre ligações b-2,6, e maior afinidade por frutanos de cadeias curtas quando comparadas com frutanos de cadeias longas. Utilizando precipitação com sulfato de amônia, cromatografia de afinidade e cromatografias de troca aniônica e catiônica, quatro frações com atividade de FEH foram purificadas. Destas quatro frações, duas foram submetidas à cromatografia de exclusão molecular, sendo que os pesos moleculares estimados para uma delas foi de 21 kDa e para outra, esta medida situou-se entre 155 e 39 kDa, devido à ampla faixa de exclusão da coluna utilizada. Os pesos moleculares das outras duas frações foram estimados por SDS-PAGE, sendo que as bandas visualizadas corresponderam a 81,3 e 57,5 kDa para uma e 57,5 kDa para a outra fração. / The occurrence of fructans has been reported in native species of a cerrado area of Reserva Biológica e Estação Experimental de Moji Guaçu. Vernonia herbacea, one of these species, presents underground organs named rhizophores which accumulate fructans of the inulin type as reserve carbohydrate. The seasonal growth pattern exhibited by plants of V. herbacea includes sprouting of buds from the rhizophores in spring, followed by a period of flower development and vegetative growth in summer, and dormancy in winter. The fructan content decreases during sprouting and flowering due to mobilization of this carbohydrate during the regeneration of the new shoots. Preliminary studies showed that FEH, the enzyme responsible for the mobilization of fructan, shows high activity only during sprouting. Fructan mobilization was detected by the increase in the amount of reducing sugar released, namely fructose. The aim of this work was to analyze the activities of the enzymes of fructan metabolism, FEH, SST, FFT and invertase and the fructan contents in rhizophores of plants induced to sprouting by defoliation. The enzyme activities were measured every 4 th day for a month after defoliation. Sprouting of new shoots started around the 13 th day, while an increase in FEH activity was detected between 13 and 20 days after defoliation. The results suggest that fructan depolimerization and sprouting are concomitant processes in V. herbacea that occur naturally during the phenological cycle; however, these processes can also be induced by defoliation during other stages of the phenological cycle. FFT seems to act together with FEH by catalyzing the decrease in fructan chain size during shoot regrowth, while SST was inhibited, possibly, due to interruption of sucrose supply to rhizophores from the aerial organs. The characterization and partial purification of FEH were done using rhizophores from plants which were induced to sprouting by defoliation. The optimal pH and temperature for FEH activity were pH4,5 and 30ºC, respectively. The substrate concentration curve exhibited a sigmoid shape, suggesting that FEH of V. herbacea is an alosteric enzyme. Additionally, this enzyme shows more specificity to b-2,1 than to b-2,6 linked fructan and higher affinity for short chain when compared to long chain fructans. Four fractions presenting FEH activity were partially purified by a combination of ammonium sulfate precipitation, affinity chromatography, and anion and cation exchange chromatographies. Two of these were submitted to size exclusion chromatography and the apparent molecular size for one of them was 21 kDa and for the other it was estimated to be between 39 and 155 kDa, due to the wide exclusion limit of the column used. The molecular size of the next two fractions were estimated by SDS- PAGE and the visualized bands corresponded to 81.3 and 57.5 kDa for the first fraction and to 57.5 kDa for the second one.
158

Dialelo parcial circulante interpopulacional em milho (Zea mays L.): efeito do número(s) de cruzamentos. / Circulant partial diallel in an interpopulation of maize: efect of the number (s) of crosses.

Sandro Ricardo Fuzatto 15 April 2003 (has links)
No esquema de cruzamentos do dialelo parcial circulante interpopulacional (DPCI) cada linhagem da população é cruzada com s linhagens da população contrastante. O objetivo deste trabalho foi estudar o efeito do número s nas estimativas de capacidade geral de combinação (CGC) e capacidade especifica de combinação (CEC) de linhagens S1 para duas populações contrastantes (GN-03 e GN-04) de milho (Zea mays L.). Dois dialelos (DPCI A e DPCI B) com 50 linhagens cada, foram cruzadas (GN-03 x GN-04) usando s=6, de acordo com o esquema circulante de cruzamento. Dos 300 híbridos possíveis de cada dialelo, foram obtidos 297 no DPCI (A) e 282 no DPCI B. Os híbridos foram avaliados em três locais (Piracicaba-SP e Uberlândia-MG, com três repetições; e em Jataí-GO com duas repetições); o DPCI B foi avaliado somente nos dois primeiros locais. Os híbridos foram divididos em seis experimentos para cada DPCI. As análises foram realizadas para cada experimento e agrupadas posteriormente; os caracteres analisados foram peso de espigas (t/ha) e altura de planta (cm). As análises do DPCI foram realizadas para diferentes tamanhos de s, a saber, s=3, 4, 5, e 6. A produtividade média dos híbridos S1 x S1 nos dois grupos variou de 94% a 99% em relação à média das testemunhas em Uberlândia e Piracicaba. Na época safrinha avaliada em Jataí, a média dos híbridos foi 17% superior a média da testemunha. A fonte de variação CEC não mostrou significância em todos locais e caracteres avaliados. Em alguns casos a perda de graus de liberdade para a fonte de variação CEC com a redução de s, diminuiu o poder do teste de F. A redução de s levou a uma maior variação das estimativas de CGC e também a uma diminuição na precisão das estimativas de CEC. Os coeficientes de correlação (r) entre os valores obtidos pelo modelo reduzido ( j i ij gˆ + gˆ + ˆ = Y ˆ m ) com os observados ( ij ij j i ij e + s + g + g + = Y m ) foram calculados para ambos os dialelos em todos os locais. Os maiores coeficientes de correlação foram observados com os menores valores de s, induzindo à falsa interpretação de que as estimativas de CEC têm pouca influência na média do híbrido.Resultados consistentes foram obtidos quando utilizou-se o mínimo de cinco cruzamentos por parental (s=5), pois pode-se obter estimativas significativas e adequadas de CGC e CEC. As estimativas de componentes de variância ao nível interpopulacional foram estimados para o caráter peso de espigas, usando s=6 . As estimativas de variância aditiva expressas em (g/planta)2 foram 120,56, 61,92 e 38,44 para os locais Piracicaba, Uberlândia e Jataí, respectivamente. A variância de dominância foi superior a variância aditiva ao nível interpopulacional em todos os locais. As relações encontradas foram 6,05, 4,30 e 7,15 para os locais Piracicaba, Uberlândia e Jataí, respectivamente evidenciando a importância dos efeitos não aditivos entre as populações. / In the partial mating scheme, each line of one population is crosses with a number (s) of lines of the opposite population. The objective of this work was to study the effect of the number s in the estimates of general combining ability (GCA) and specific combining ability (SCA) of S1 lines from two contrasting populations (GN-03 and GN-04) of maize (Zea mays L.) crossed according to the partial diallel. Two groups (GA and GB) of fifth S1 lines were randomly crossed (GN-03 x GN-04) using s=6. From the 300 possible crosses in each group, some were last resulting 297 in GA and 282 in GB. Crosses were evaluated in three locations (Piracicaba-SP and Uberlandia-MG with three replications; and Jatai-GO with two replications); group GB was evaluated only in the first two locations. The whole set of crosses was divided into six experiments for each group. The analyses of variance were performed for each experiment and then grouped over experiments. The traits ear yield (t/ha) and plant height (cm) were analysed. The analyses were performed for varying number of crosses per line; i.e., for s=3, 4, 5, 6. Ear yield of S1 xS1 crosses in both groups varied from 94% to 99% in relation to the mean of both checks in Uberlandia and Piracicaba. In Jatai, only group GA in midseason planting yielded 17% more than the average of checks. Specific combining ability didn’t showed significance for every traits and locations. While general combining ability was always significant. Decreasing s led to a higher variation in the estimates of GCA and also to a decrease in the precision of SCA estimates. The coefficient of correlation between observed means ( ij ij j i ij e + s + g + g + = Y m ) and predicted means through the reduced model ( j i ij gˆ + gˆ + ˆ = Y ˆ m ) was calculated for boths groups in all locations. The higher coefficients of correlations were observed for smaller s values, leading to a miss interpretation. That SCA is of low importance in the phenotypic expression. Consistent results were observed by using s=5 allowing the detection of significance and good of the estimates of GCA and SCA. The estimates of the interpopulation variance components were obtained for ear yield using s=6. The estimates of the additive genetic variance expressed in (g/plant)2 were 120.56, 61.92 and 38.44 in Piracicaba, Uberlandia and Jatai, respectively. The dominance variance were higher than the additive variance in all locations; the ratios ) / ( 2 A 2 D s s were 6.1, 4.3 and 7.2, respectively, indicating the importance of the non additive effects in the interpopulation.
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Avaliação de cultivares de feijão (Phaseolus vulgaris L.) para o sistema orgânico de produção / Evaluation of cultivars of beans (Phaseolus vulgaris L.) to the organic management of production

Jacqueline Camolese de Araujo 11 August 2008 (has links)
Com o objetivo de avaliar as características, as produções e os comportamentos das diferentes cultivares de feijão de inverno irrigado em sistema de produção orgânico, conduziu-se um experimento na área experimental pertencente à Escola Superior de Agricultura \"Luiz de Queiroz/Universidade de São Paulo, localizada na Fazenda Areão e no núcleo experimental do Grupo de Agricultura Orgânica Amaranthus. Os seguintes parâmetros foram avaliados: a produtividade, número de flores por planta, número de vagens por planta, número de grãos por vagem, o índice de área foliar bem como o teor de nutrientes para cada variedade. As variedades analisadas foram do Grupo Carioca: BRS-Pérola, BRS-Aporé, IAC- Votuporanga e IPR- Juriti, e do Grupo Preto: IAC-Tunã e BRS-Valente. De acordo com o que foi analisado, os resultados permitem concluir que: (i) não houve diferença estatística entre os tratamentos, (ii) todas as cultivares avaliadas apresentaram ótimo desempenho sob manejo orgânico. / The goals of this study were to evaluate the characteristics, productivities and behaviors of different cultivars of common bean in an irrigate organic management system in the winter. The experiment was carried out at the experimental area of the Group of Organic Agriculture Amaranthus from Escola Superior de Agricultura \"Luiz de Queiroz\"/University of São Paulo, in Fazenda Areão, in Piracicaba, São Paulo State, Brazil. The following agronomic parameters related to common bean crop were used for statistical analysis: grain yield, number of flowers per plant, number of pods per plant and grains per pod, leaf area index, as well as leaf nutrient content for each cultivar. It were tested the following varieties from Carioca Group: BRS-Pérola, BRS-Aporé, IACVotuporanga and IPR- Juriti, and from Black Group: IAC-Tunã and BRS-Valente. The results showed that: (i) there were no statistical differences between the treatments, (ii) all the tested varieties had great productivity under organic management system.
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The production of vegetable crops under protection for small-scale farming situations

Mashego, Ditshwanelo Cynthia 11 July 2006 (has links)
Experiments were conducted with tomato under shade netting and with lettuce in a vertical hydroponic system at the Hatfield Experimental Farm, University of Pretoria. The objectives of the study were: 1. To evaluate the effect of different types of shade netting on tomato production 2. To develop a vertical hydroponic system for lettuce production which would be suitable for use by small-scale farmers. In the tomato trial the highest number of fruit per plant (47) was produced under 12% white shade and 40% black shade nets, and the lowest fruit number (35) was produced under 30% black net. The highest yield of 6.2 kg per plant was obtained under the 18% white net while 30% black net produced the lowest yield of 3.9 kg per plant. The test yield of lettuce grown in plastic tubes with eight vertically arranged plant positions were obtained with a continuous high flow rate of the nutrient solution. However, a simplified manual system where the nutrient solution was delivered by gravity from a small reservoir tank resulted in comparable yields. / Dissertation (M Inst Agrar (Agronomy))--University of Pretoria, 2007. / Plant Production and Soil Science / unrestricted

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