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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.
51

Aplicação via fertirrigação de soluções com diferentes condutividades elétricas para produção de gérbera (Gerbera jamesonii L.) sob ambiente protegido

Mota, Poliana Rocha D'Almeida [UNESP] 21 August 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-08-21Bitstream added on 2014-06-13T19:03:15Z : No. of bitstreams: 1 mota_pra_dr_botfca.pdf: 983531 bytes, checksum: 98e21bceb1a37609beeecbe091b7d53d (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Universidade Estadual Paulista (UNESP) / O presente trabalho foi desenvolvido com o objetivo de avaliar a aplicação, via fertirrigação, de soluções com diferentes condutividades elétricas, bem como seu monitoramento e controle, no desenvolvimento e qualidade de cultivares de gérbera (Gerbera jamesonii L.) em vaso, como meio de indicar a melhor concentração de sais a ser aplicada. O experimento foi conduzido sob cultivo protegido no Departamento de Recursos Naturais/Ciência do Solo da Fazenda Experimental Lageado, pertencente à Faculdade de Ciências Agronômicas da UNESP Campus de Botucatu, município de Botucatu, Estado de São Paulo. Adotou-se o delineamento experimental em blocos casualizados com quatro repetições em esquema fatorial constando de cinco níveis de condutividade elétrica (CE) e dois cultivares em cada ciclo, totalizando quarenta parcelas. Os níveis de CE (soluções) foram: 0,5; 2,0; 3,5; 5,0 e 6,5 dS m-1, e o monitoramento da concentração de sais da solução do substrato na zona radicular das plantas foi realizado por meio da retirada da solução com extratores, duas vezes por semana. Durante o período de condução de cada experimento foi avaliado o pH, área foliar, fitomassa seca, quantidade de botões florais, teor e acúmulo de macro e micronutrientes na parte aérea da planta e teor de macro e micronutrientes na folha diagnóstico, concentração de nitrato na seiva da folha, concentração de nitrato e potássio na solução do substrato e intensidade de cor verde. Ao final do experimento foram avaliadas a fitomassa seca e o teor e acúmulo de macro e micronutrientes na parte aérea de plantas consideradas no ponto de comercialização e a classificação das plantas quanto à qualidade. Para as análises pósprodução foram avaliadas as seguintes variáveis: altura de plantas no início e ao final do experimento pós-produção, diâmetro da superfície foliar do vaso... / The present research was developed with the objective of evaluating application through fertigation of solutions with different electrical conductivities as well as monitoring and control on the development and quality of gerbera (Gerbera jamesonii L.) in potted cultivars in order to find the best salt concentration content to apply. The experiment was conducted under greenhouse conditions at the Natural Resources Department Soil Science area on Lageado Experimental Farm, owned by Agronomy Science Faculty on Botucatu Campus, located in the town of Botucatu, state of Sao Paulo, Brazil. The experimental design were randomized blocks with four repetitions in factorial scheme consisting of five electrical conductivity levels (EC) and two cultivars in each cycle, totalizing forty lots. The levels of EC (solutions) were: 0.5; 2.0; 3.5; 5.0 e 6.5 dS m-1, and the monitoring of salt concentration in the substratum solution in the root zone of the plants was done through the extraction of the solution by means of extractors twice a week. During the conduction of each experiment the following were evaluated: pH, leaf area, dry mass, floral bud quantity, accumulation of macro and trace element contents on the aerial portion of the plant, macro and trace element contents in the diagnostic leaf, nitrate concentration in the sap of the leaf, nitrate and potassium concentration in the substratum solution and green color intensity. At the finish of the experiment were evaluated: dry mass, accumulation of macro and trace element contents on the aerial portion of the plants considered to have reached their point of commercialization, as well as the classification of these plants with regard to their quality. For the post production analysis, the following parameters were evaluated: plant height at the start and at the finish of the post production experiment, diameter of... (Complete abstract click electronic access below)
52

Potencial de uso de gramíneas como substrato pasteurizado no cultivo do cogumelo Pleurotus ostreatus (Jacq.) P. Kumm

Vieira, Fabrício Rocha [UNESP] 30 July 2012 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:24:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-07-30Bitstream added on 2014-06-13T20:31:57Z : No. of bitstreams: 1 vieira_fr_me_botfca.pdf: 1347987 bytes, checksum: 27d81f495f8f2bff5b1ec18fa111bf93 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / O cultivo de cogumelos comestíveis e medicinais pode ser realizado em diversos substratos liginocelulósico em sistema axênico e pasteurizado. O gênero Pleurotus é conhecido principalmente pela espécie Pleurotus ostreatus conhecido popularmente como cogumelo ostra, shimeji ou hiratake. Neste trabalho, investigou-se a variabilidade genética de quatro linhagens de Pleurotus ostreatus pela técnica RAPD, o crescimento micelial em meio de cultura sólido, parâmetros da compostagem (umidade do substrato, dinâmica da relação C/N, pH, perda de massa fresca, celulose, hemicelulose, lignina, proteína total e fibra total), produtividade, eficiência biológica e qualidade nutricional dos basidiomas (proteína total, fibra total e extrato etéreo) cultivados nos diferentes substratos em duas relações C/N. As linhagens de P. ostreatus foram coletadas de produtores do Estado de São Paulo e os materiais utilizados para a elaboração dos substratos de cultivo foram: capim braquiária, capim tobiatã, capim brizantha, palha de cana-de-açúcar, palha de trigo, bagaço de cana-de-açúcar e farelo de trigo. No primeiro experimento foi avaliado a variabilidade genética pela técnica RAPD das quatro linhagens de P. ostreatus coletadas de produtores do Estado de São Paulo. Assim foram divididos em dois grupos distintos, o primeiro grupo com as linhagens POS 09/100, POS 09/101 e POS 09/102 e o segundo grupo com a linhagem POS 98/38. Sendo que dentro do primeiro grupo as linhagens POS 09/100 e POS 09/101 apresentaram similaridade de 93%, ainda... / The cultivation of edible and medicinal mushrooms can be accomplished on various lignocellulosic substrates in system axenic or pasteurized. The Pleurotus genus is mainly known by the species as Pleurotus ostreatus popularly known oyster mushroom, shimeji or hiratake. In this study, we investigated the genetic variability of four strains of Pleurotus ostreatus by RAPD, the mycelial growth on solid medium, composting parameters (substrate moisture, dynamics of C/N ratio, pH, weight loss, cellulose, hemicellulose, lignin, total protein and total fiber), productivity and nutritional quality of mushrooms (total protein, total fiber and lipids) grown on different substrates in two C/N ratio. The strains of P. ostreatus were collected from producers of São Paulo State and the materials used for the preparation of substrates were: brachiaria grass, tobiatã grass, brizantha grass, sugar cane straw, wheat straw, sugar cane bagasse and wheat bran. In the first experiment evaluated the genetic variability by RAPD of four strains of P. ostreatus collected from producers of São Paulo State. So were divided into two distinct groups: the first group with the strains POS 09/100, POS 09/101 and 09/102 and the second group with the strain POS 98/38. Since the first group within the strains POS 09/100 and POS 09/101 showed similarly of 69% over the two aforementioned strains. In second group the strain POS 98/38 showed similarity of 36% compared to with the first group. In the second experiment evaluated the mycelial growth in culture media based on the substrate collected at the end of Phase II composting. Was used the punctuation in defined time periods (24 hours) to determine colony growth and non-parametric method of Stundent- Newman-Kills for transforming the values in growth curves higher growth rates were obtained on... (Complete abstract click electronic access below)
53

Influência de fatores do ambiente na germinação de sementes de grama-tapete (Axonopus affinis Chase) /

Pereira, Suzana Targanski Sajovic. January 2016 (has links)
Orientador: Kathia Fernandes Lopes Pivetta / Banca: Cláudia Fabrino Machado Mattiuz / Banca: Eloiza Santana Seixas Vitória / Resumo: O objetivo deste trabalho foi verificar a influência da temperatura, da luz, do substrato, das formas de semeadura, do estresse salino e hídrico na germinação da gramínea Axonopus affinis. Foram quatro experimentos, todos conduzidos em câmara de germinação, onde as condições de temperatura, umidade e fotoperíodo foram controladas; o delineamento experimental utilizado foi inteiramente casualizado e utilizou-se 100 sementes por parcela. Para o estudo da temperatura e da luz (experimento 1), os tratamentos foram arranjados em esquema fatorial 6 x 2, composto de seis condições de temperatura (constante de 20, 25, 30 e 35 ºC e alternadas de 20-30 ºC e 20-35 ºC) e duas condições de luminosidade (―claro‖: 8 horas de luz e 16 horas de escuro e ―escuro‖: 24 h na ausência de luz) e quatro repetições. Para o estudo de substrato e forma de semeadura (experimento 2) foram quatro tratamentos (sobre papel, entre papel, sobre areia e entre areia) e cinco repetições. Para o estudo do estresse salino (experimento 3) foram cinco tratamentos (concentrações de NaCl: 0, 25, 50, 75 e 100 mM) e quatro repetições. Para o estudo do estresse hídrico e formas de semeadura (experimento 4), os tratamentos foram distribuídos em esquema fatorial 3 x 2 onde foram testados três níveis de capacidade de retenção de água (50, 75 e 100%) e duas formas de semeadura (sobre areia e entre areia) e quatro repetições. Avaliou-se porcentagem de germinação e Índice de Velocidade de Germinação. Concluiu-se que a germinaç... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This work aim was verify the temperature, light, substrate, ways of sowing, and salt and hydric stress influence into the Axonopus affinis germination. All the four trials were carried out in a germination chamber under temperature, humidity, and photoperiod controlled conditions. The experimental design used was the completely randomized one, with 100 seeds in each plot. To study the temperature and light (experiment 1), the trials were arranged in a factorial scheme 6x2, with six temperature conditions (constant temperatures of 20, 25, 30 and 35 °C and alternate temperatures of 20-30 °C and 20-25 °C) and two lightning conditions (light: 8 hours of light and 16 hours of dark and "dark": 24 h in the dark) and four replications. To the substrate and sowing trial (experiment 2) we used four treatments (on paper, between paper, on sand, and between sand) with five replications. To the salt stress trial (experiment 3) we used five treatments (NaCl concentrations: 0, 25, 50, 75, and 100 mM) with four replications. To the hydric stress trial the treatments were arranged in a 3x2 factorial scheme (experiment 4) where we tested three levels of water retention capacity (50, 75, and 100%) and two ways of sowing (on sand and between sand) and four replications. We evaluated the germination percentage and Germination Time Index. We could conclude that the seed germination was more effective when the temperature was alternated of 20-30 °C and 20-35 °C, under light condition, and on a pape... (Complete abstract click electronic access below) / Mestre
54

Desenvolvimento e viabilidade econômica de mudas de espécies florestais nativas com o uso de fertirrigação em substratos a base de biossólido compostado /

Uesugi, Gláucia, 1982. January 2014 (has links)
Orientador: Magali Ribeiro da Silva / Coorientador: Danilo Simões / Banca: Gisela Ferreira / Banca: Paulo André de Oliveira / Resumo: O maior contribuinte à poluição orgânica dos corpos-d'agua é o esgoto doméstico. Têm-se procurado alternativas para a reutilização do material, que pode ser usado na composição de substratos para plantas. Desta forma, o objetivo desta pesquisa foi avaliar o desenvolvimento e a viabilidade econômica de mudas de Croton urucurana (sangrad'água) e Cytharexyllum myrianthum (pau-viola), produzidas com substratos a base de biossólido compostado sob diferentes manejos de fertirrigação. Cada espécie constituiu-se de um experimento e se caracterizou por usar biossólido compostado (BC) associado à casca de arroz carbonizada (CAC) nas proporções de 2:1 e 1:2 (base em volume) e substrato comercial (testemunha), combinadas a aplicações de três concentrações de fertilizantes via fertirrigação. O delineamento experimental utilizado foi o inteiramente casualizado, nove tratamentos, cada qual com quatro blocos de 12 plantas, sendo oito úteis para a avaliação. Para avaliar o desenvolvimento das mudas, as seguintes variáveis foram medidas: altura (H), diâmetro de colo (D) e relação H/D. Para avaliar a viabilidade econômica foram usados os seguintes índices: Valor Presente Líquido (VPL), Taxa Interna de Retorno (TIR), Payback, Valor Anual Uniforme Equivalente (VAUE), Relação Benefício/Custo (RBC) e Ponto de Equilíbrio. Para ambas as espécies, as mudas provenientes dos substratos compostos por biossólido compostado atingiram as maiores alturas e diâmetros do colo em menor tempo, além de apresentarem a maior rentabilidade na solução mais diluída, com destaque para o substrato S2, o qual possui maior proporção de biossólido compostado. / Abstract: The largest contributors to organic pollution of water is domestic sewage. Alternatives have been sought for the reuse of this material, which can be used in the composition of substrates for the production of forest seedlings. Thus, the objective of this research was to evaluate the development and economic viability of Croton urucurana and Cytharexyllum myrianthum seedlings, produced in composted biosolids substrates under different fertigation management. Each species was an experiment. They was characterized by using composted sludge (BSC) and carbonized rice husk (CAC) in proportions of 2:1 and 1:2 (based on volume) and commercial substrate (control); and three different fertilizers doses were applied by fertigation. The experimental design was completely randomized, nine treatments, four blocks of 12 plants, eight plants for evaluation. To assess the seedling's growing, the following parameters of the seedlings were measured: height (H), stem diameter (D) and ratio H/D. To evaluate the economic viability, the following indices were used: Net Present Value, Internal Rate of Return, Payback, Equivalent Annual Value, Ratio Benefit/Cost and Break Even Point. For both species, seedlings from substrates composed of composted sludge got the greatest heights and stem diameters in less time. These treatments presented the highest profitability values when used the more dilute solution, especially S2 substrate, which has the highest proportion of composted biosolids. / Mestre
55

Condicionadores em substratos para a formação de mudas de eucalipto com dois níveis de irrigação /

Muraishi, Reginaldo Itiro. January 2012 (has links)
Orientador: João Antonio Galbiatti / Banca: Carlos Eduardo Angeli Furlani / Banca: Renato Farias do Vale Junior / Banca: Fabio Olivieri de Nobile / Banca: Emerson Fachini / Resumo: O uso de vermiculita e polímeros agrícolas como condicionadores em substratos no Brasil têm contribuído para melhorar a germinação de sementes, desenvolvimento das plantas, além da redução das perdas de água de irrigação. O objetivo deste trabalho foi quantificar e estimar as misturas dos condicionadores em substratos de compostos orgânicos lixo e compostos orgânicos de poda de arvores e a redução da irrigação na produção de mudas de Eucalyptus citriodora Hook. Foram testados duas lâminas d'água (50% e 100% da evapotranspiração de referência medida pelo atmômetro) e 2 condicionadores no substrato em 3 concentrações (vermiculita 15%, 20% e 30% e polímeros 0,5%, 1,0% e 2,0% em volume), além de duas testemunhas que receberam 50% e 100% de irrigação. O experimento foi conduzido em delineamento blocos casualizados, com arranjo fatorial em três blocos e as médias comparadas pelo teste de Tukey a 5% de probabilidade. Foi avaliado o número de folhas, altura da planta, diâmetro do colo e massa de matéria seca. Da análise dos resultados em condição de produção de mudas, concluiu-se que a vermiculita apresentou resultado superior em irrigação com lâmina d'agua a 50% e a utilização de polímero a 0,5% sob lâmina d'agua 100% irrigação foi melhor tratamento para massa de matéria seca. Além disso, verificou-se que não é recomendável a utilização do polímero em doses acima de 0,5% e vermiculita acima de 15% / Abstract: The use of vermiculite and polymers as conditioners for agricultural substrates in Brazil, have improved seed germination, plant development, and reduce losses of irrigation water. The objective of this study was to quantify and estimate mixtures of conditioners on substrates of organic compounds waste and organic compounds of trees pruning and reduction of irrigation in the production of seedling Eucalyptus citriodora Hook. It was tested the irrigation with two water depths with (50% and 100% of evapotranspiration by atmometer) measured and 2 conditioning in the substrate in 3 concentrations (vermiculite with 15%, 20% and 30% and polymers 0.5%, 1,0% and 2.0% by volume), besides two controls which received only 50% and 100% of irrigation. The experiment was conducted by a randomized block design with factorial arrangement, three blocks and the average was compared by Tukey test at 5% probability. Was evaluated the number of leaves, plant height, stem diameter and dry matter. Analysis of the results in conditions of seedlings production, it was concluded that the vermiculite showed superior results in a water irrigation with the use of 50% and the polymer application to 0.5% in a water irrigation, 100% better treatment for dry matter. Besides, it was found that it is not advisable to use of the polymer at doses above 0.5% and above 15% vermiculite / Doutor
56

Desenvolvimento e viabilidade econômica de mudas de espécies florestais nativas com o uso de fertirrigação em substratos a base de biossólido compostado

Uesugi, Gláucia [UNESP] 31 January 2014 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-01-31Bitstream added on 2014-06-13T21:00:55Z : No. of bitstreams: 1 000759004.pdf: 1797268 bytes, checksum: 448cf21762d0ec7b3123e04542a45cf4 (MD5) / O maior contribuinte à poluição orgânica dos corpos-d´'agua é o esgoto doméstico. Têm-se procurado alternativas para a reutilização do material, que pode ser usado na composição de substratos para plantas. Desta forma, o objetivo desta pesquisa foi avaliar o desenvolvimento e a viabilidade econômica de mudas de Croton urucurana (sangrad'água) e Cytharexyllum myrianthum (pau-viola), produzidas com substratos a base de biossólido compostado sob diferentes manejos de fertirrigação. Cada espécie constituiu-se de um experimento e se caracterizou por usar biossólido compostado (BC) associado à casca de arroz carbonizada (CAC) nas proporções de 2:1 e 1:2 (base em volume) e substrato comercial (testemunha), combinadas a aplicações de três concentrações de fertilizantes via fertirrigação. O delineamento experimental utilizado foi o inteiramente casualizado, nove tratamentos, cada qual com quatro blocos de 12 plantas, sendo oito úteis para a avaliação. Para avaliar o desenvolvimento das mudas, as seguintes variáveis foram medidas: altura (H), diâmetro de colo (D) e relação H/D. Para avaliar a viabilidade econômica foram usados os seguintes índices: Valor Presente Líquido (VPL), Taxa Interna de Retorno (TIR), Payback, Valor Anual Uniforme Equivalente (VAUE), Relação Benefício/Custo (RBC) e Ponto de Equilíbrio. Para ambas as espécies, as mudas provenientes dos substratos compostos por biossólido compostado atingiram as maiores alturas e diâmetros do colo em menor tempo, além de apresentarem a maior rentabilidade na solução mais diluída, com destaque para o substrato S2, o qual possui maior proporção de biossólido compostado. / The largest contributors to organic pollution of water is domestic sewage. Alternatives have been sought for the reuse of this material, which can be used in the composition of substrates for the production of forest seedlings. Thus, the objective of this research was to evaluate the development and economic viability of Croton urucurana and Cytharexyllum myrianthum seedlings, produced in composted biosolids substrates under different fertigation management. Each species was an experiment. They was characterized by using composted sludge (BSC) and carbonized rice husk (CAC) in proportions of 2:1 and 1:2 (based on volume) and commercial substrate (control); and three different fertilizers doses were applied by fertigation. The experimental design was completely randomized, nine treatments, four blocks of 12 plants, eight plants for evaluation. To assess the seedling's growing, the following parameters of the seedlings were measured: height (H), stem diameter (D) and ratio H/D. To evaluate the economic viability, the following indices were used: Net Present Value, Internal Rate of Return, Payback, Equivalent Annual Value, Ratio Benefit/Cost and Break Even Point. For both species, seedlings from substrates composed of composted sludge got the greatest heights and stem diameters in less time. These treatments presented the highest profitability values when used the more dilute solution, especially S2 substrate, which has the highest proportion of composted biosolids.
57

Substrato e irrigação em ora-pro-nóbis (Pereskia aculeata Mill.) /

Andrade, Reginaldo Rodrigues de. January 2012 (has links)
Orientador: João Antônio Galbiatti / Coorientador: Luiz Carlos Pavani / Banca: Sueli Ciabotti / Banca: Luciana Santos Rodrigues Costa Pinto / Banca: José Carlos Barbosa / Banca: José Renato Zanini / Resumo: Resíduos orgânicos domiciliares ou industriais, são facilmente disponibilizados e podem, após compostagem, ser utilizados na composição de substratos alternativos de baixo custo e com grandes benefícios para a planta e para o ambiente. Hortaliças não convencionais, conhecidas popularmente por suas qualidades nutricionais, como a ora-pro-nóbis (Pereskia aculeata Mill.), começam a ser cultivadas no Brasil, de forma sistematizada, mas sem conhecimento comprovado das respostas de técnicas de cultivo, como as da irrigação e da utilização de composto orgânico. Por isso, procedeu-se ao cultivo de plantas de P. aculeata em vasos dentro de ambiente protegido, utilizando-se o método de estaquia caulinar. As variáveis de produção foram doses de composto orgânico no substrato (CO), oriundo da compostagem de resíduos orgânicos de origem industrial e agropecuária, do município de Uberlândia - MG, equivalentes a 0%, 15%, 30%, 45% e 60% do volume total do substrato e lâminas de irrigação (Li) correspondentes a 50%, 75% e 100% da evapotranspiração de referência (Et0), estimada por meio da equação de Penman-Monteith (FAO-56), com a utilização dos dados meteorológicos obtidos na estação automatizada da Universidade Federal de Uberlândia. O delineamento experimental foi o inteiramente casualizado (DIC) com 4 repetições. A irrigação foi realizada a cada 3 dias com a soma dos volumes de água calculados diariamente. Cento e vinte e dois dias após o plantio das estacas efetuou-se o corte das plantas e a determinação da massa seca em folhas, caules e raízes, e dos teores de proteína, cálcio (Ca) e ferro (Fe) nas folhas. Os resultados das análises estatísticas permitiram concluir que, excetuando-se para massa seca em raízes, houve interação entre as Li e as doses de CO para as demais variáveis. O aumento das... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Organic household or industrial waste, are easily available and can, after composting, be used in the composition of alternative substrates with low cost and great benefits for the plant and the environment. Unconventional vegetables, popularly known for its nutritional qualities, as Pereskia aculeata Mill., began to be cultivated in Brazil, in a systematic way, but without proven knowledge of growing techniques such as irrigation and use of organic compound. Therefore, we grow plants of P. aculeata in pots inside of a greenhouse, using the method of stem cuttings. Were broadly two the variables tested: doses of the organic compost in the substrate (CO), produced by composting organic waste from industry and agriculture in Uberlândia - MG, equivalent to 0%, 15%, 30%, 45% and 60% the total volume of the substrate; irrigation depths (Li) corresponding to 50%, 75% and 100% of the reference evapotranspiration (Et0) estimated with the FAO 56 Penman-Monteith equation, using meteorological data obtained at an automated station of the Federal University of Uberlândia. The experimental design was a completely randomized design with 4 replications. The irrigation was done every 3 days with the sum of the water volumes calculated daily. One hundred and twenty-two days after planting the plants were cut off and it was determined the dry masses of leaves, stems and roots, and the content of protein, calcium (Ca) and iron (Fe) in the leaves. The results of the statistical analyzes showed that, except for dry weight in roots, there was interaction between Li and CO levels for the other variables. The accumulation of... (Complete abstract click electronic access below) / Doutor
58

Yield and quality parameters of tomato cultivars as affected by different soilless production systems and beneficial micro-organisms.

Maboko, Martin Makgose. January 2013 (has links)
Most tomato cultivars used for commercial food production are imported into South Africa. Optimal growing conditions for these specific cultivars need to be determined, as wrong cultivar choices can lead to great financial losses. Lack of information on selecting well-performing cultivars may lead to lower yield or unacceptable fruit quality. Information on the performance of tomato cultivars under South African conditions, utilizing plastic tunnels or shadenet structures under soilless cultivation is still very limited. Soilless cultivation of vegetables is becoming a preferable over in-soil cultivation due to the improved yield and quality of produce, efficient water and nutrients usage by the crop; furthermore, the grower can regulate nutrient solution, electrical conductivity and pH of the nutrient solution. To identify the optimal system for growing tomatoes hydroponically, the performance of four tomato cultivars (‘FA593’, ‘Miramar’, ‘FiveOFive’ and ‘Malory’) under different growing conditions was evaluated: directly planted in soil under 40% shadenet with drip irrigation, a closed hydroponic system under 40% shadenet, an open bag system under 40% shadenet, or an open-bag system in a temperature controlled as well as a non-temperature controlled tunnel. The study revealed that ‘Miramar’ performed better than the other cultivars in all production systems, with the exception of soil cultivation where there were no differences amongst the four cultivars. Fruit cracking was found to be directly correlated with fruit size, as the large-sized cultivars ‘Malory’ and ‘FA593’ were more susceptible than the other two cultivars. Plants grown under shadenet were prone to fruit cracking and raincheck as well as early blight. Higher yields were obtained when plants were produced in the open bag system under temperature controlled conditions and in the closed system under shadenet. Growing tomatoes in the non-temperature controlled tunnel resulted in high incidences of fruit cracking, poor yield and pre-mature fruit ripening probably due to high and fluctuating temperatures under such conditions. The average marketable yield was 88% and 59% of the total yield in the temperature controlled and non-temperature controlled tunnels, respectively. A further experiment was carried out to improve yield and quality of tunnel tomatoes using beneficial micro-organisms, i.e., arbuscular mycorrhiza fungi (AMF) at different nutrient concentrations. Tomato seedlings were treated with Mycoroot™ containing four mycorrhiza species (Glomus etunicatum, Paraglomus occultum, Glomus clarum and Glomus mossea) at transplanting and subsequently transferred to either a temperature controlled or a non-temperature controlled tunnel under the recommended (100%) or reduced (75 and 50%) nutrient concentrations. Sawdust was used as a growing medium in this experiment. Application of AMF neither enhanced plant growth, yield, nor fruit mineral nutrient concentrations; although fruit Mn and Zn concentrations in the temperature controlled tunnel increased significantly following AMF application. Plants grown in the non-temperature controlled tunnel had significantly poorer plant growth, and lower yield and lower fruit mineral concentrations, compared with fruit from plants in the temperature controlled tunnel. Tomato plants in the non-temperature controlled tunnel had higher levels of micro-elements in leaf tissue, compared with those in the temperature controlled tunnel. The highest yields were obtained from plants fertigated with 75% of the recommended nutrient concentration, as compared with the 100 and 50% nutrient concentrations. When coir was subsequently used as the growing medium, Mycoroot™ applied at seeding and transplanting did not enhance mycorrhizal colonization or fruit quality. Growing tomatoes under reduced nutrient supply reduced the total soluble solids in the juice of the fruit, but improved total and marketable yield, as well as the number of marketable fruit. This effect was more substantial in the temperature controlled than in the non-temperature controlled tunnel. Fruit firmness and leaf chlorophyll concentrations were significantly higher in plants grown in the temperature controlled tunnel. Growing tomatoes in sawdust improved the leaf Mn and Ca concentration over that of tomato plants grown in coir. Mycorrhizal colonisation did not have a beneficial effect on tomato yield and quality. The study indicated that cultivar selection was important in obtaining the highest yield and quality of tomato using the closed hydroponic system under shadenet and the open bag hydroponic system in the temperature controlled tunnel. Temperature controlled tunnels with a pad–and-fan cooling system are still an effective way of cooling the tunnel environment which resulted in high yield and high quality of tomatoes with a higher fruit mineral content than that obtained under non-temperature controlled conditions where only natural ventilation is relied on. Results also demonstrated that mycorrhizal colonization in soilless condition has limited beneficial effects in allowing for better nutrient uptake and thereby for improved yield and quality of tomatoes. Further studies, including different media, nutrient composition and concentrations, need to be carried out to investigate the possible causes of AMF failure to improve yield, despite good AMF root colonization. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2013.
59

Utilization of municipal solid waste compost in horticulture

Lu, Wenliang. Sibley, Jeffrey Lynn, January 2008 (has links) (PDF)
Dissertation (Ph.D.)--Auburn University, 2008. / Abstract. Includes bibliographic references.
60

Desenvolvimento e qualidade de mudas clonais de Eucalyptus grandis x Eucalyptus urophylla em função da adubação fosfatada em substratos

Viteri Cabezas, Wellington Patricio [UNESP] 31 August 2012 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:20Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-08-31Bitstream added on 2014-06-13T20:40:16Z : No. of bitstreams: 1 vitericabezas_wp_me_botfca.pdf: 276987 bytes, checksum: fefb989fa21883ab05774fb93da9941f (MD5) / A produção de mudas da espécie Eucalyptus grandis x Eucalyptus urophylla tem crescido muito nos últimos anos no Brasil, devido a sua boa adaptação nos diferentes solos e regiões, possuindo comportamentos diferentes quanto à exigência nutricional em diferentes tipos de substrato que o mercado oferece. O conhecimento desses comportamentos trará benefícios econômicos e diminuição dos impactos ambientais causados pelo uso excessivo de fertilizantes. Neste trabalho buscou-se avaliar o efeito de doses de fósforo em três tipos de substratos na produção de mudas de Eucalyptus grandis x Eucalyptus urophylla. O experimento foi inteiramente casualizado em fatorial 3x4, utilizando 3 substratos e 4 doses de fósforo na base, totalizando 12 tratamentos distribuídos em 4 parcelas com 25 plantas. O adubo usado na fertilização de base foi o superfosfato simples e as doses foram de 0, 160, 320 e 480 g por m3 de substrato. Os substratos utilizados foram: Carolina Soil® a base de turfa, vermiculita e casca de arroz carbonizada; substrato Mecplant® a base de casca de pinus e vermiculita e substrato a base de fibra de coco e vermiculita. As avaliações do experimento constituíram-se de análise química do substrato e características morfológicas das mudas: altura da parte aérea, diâmetro do coleto, massas secas da parte aérea e radicular e qualidade de raiz. Em função dos resultados obtidos pode-se inferir que para o substrato Carolina Soil® a dose que apresentou mudas com maior desenvolvimento foi a de 320 g m-3. Para o substrato fibra de coco + vermiculita foi a de 160 g m-3 e para o substrato a Mecplant® tanto na dose zero quanto na de 480 g m-3 apresentaram resultados semelhantes, indicando a não necessidade de aplicação de P na adubação de base neste substrato. Os três substratos produziram mudas semelhantes e dentro do padrão de qualidade adequado / The production of cuttings of the species Eucalyptus grandis x Eucalyptus urophylla has grown significantly in recent years in Brazil due to its good adaptation to different types of soil and region, having different behaviors a far as its nutritional demands on the different kinds of substrate offered by the market. Knowledge of these behaviors will bring economic benefit and a diminishing of the environmental impact caused by the excessive use of fertilizers. This investigation sought to validate the effect of doses of phosphorus on three types of substrate in the production of cuttings of Eucalyptus grandis x Eucalyptus urophylla. The experiment was entirely done on 3x4 factorial, using 3 substrates of 4 doses of phosphorous on the base, totaling 12 applications distributed among 4 parcels with 25 plants each. The fertilizer used for the base was a simple superphosphate and the doses were 0, 160, 320 and 480 g per m3 of substrate. The substrates used were: truffle based Carolina Soil®, vermiculite and carbonized rice shells, vermiculite and pinus shell based Mecplant® and coconut fiber and vermiculite substrate. Evaluations in the experiment include chemical analysis of the substrate and morphological characteristics of the cuttings: height of the airborne area, stalk diameter, dry spots on the airborne area and root and overall quality of the root. From the obtained results, it’s possible to infer that for the Carolina Soil® substrate, the dosage that showed the best growth was 320 g m3. For the coconut + vermiculite substrate the best results came with 160 g m-3 and for the Mecplant® substrate, both the zero dose and the 480 g m3 showed similar results, indicating that there isn’t a need for the application of P on the fertilizing of the base of this substrate. The three substrates will produce similar cuttings and within an adequate pattern of quality

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