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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.
11

Efeito do composto orgânico e adubação potássica em atributos do solo e da beterraba

Magro, Felipe Oliveira [UNESP] 23 November 2012 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-11-23Bitstream added on 2014-06-13T20:04:02Z : No. of bitstreams: 1 magro_fo_dr_botfca.pdf: 686338 bytes, checksum: 9289d13e2c7c5c680eb158bc5907dbb1 (MD5) / O objetivo deste trabalho foi avaliar a resposta da beterraba à doses de composto orgânico e adubação potássica em cobertura, e o efeito destes em atributos do solo. Foi realizado um experimento na Fazenda Experimental São Manuel (FCA/UNESP), localizada em São Manuel-SP, com 10 tratamentos, em esquema fatorial 5 x 2, e delineamento experimental em blocos ao acaso, com quatro repetições. Foram avaliadas cinco doses de composto orgânico (0; 20; 40; 60 e 80 t ha-1) na presença (60 kg ha-1 de K2O) e ausência da adubação potássica em cobertura. Para todos os tratamentos foi feita adubação com nitrogênio, fósforo e potássio no plantio, de acordo com a análise de solo. As características avaliadas foram: propriedades químicas do solo ao longo do ciclo, características vegetativas (altura; número de folhas; massa fresca e seca da parte aérea, raiz e da planta e área foliar) ao longo do ciclo, acúmulo e exportação de macronutrientes (nitrogênio, fósforo, potássio, cálcio, magnésio e enxofre) e produção (massa média, produtividade, diâmetro e comprimento das raízes). As doses de composto orgânico proporcionaram efeito positivo nas propriedades químicas do solo durante todas as épocas avaliadas. A ordem decrescente dos macronutrientes exportados pelas raízes de beterraba foi: potássio > nitrogênio > fósforo > magnésio > enxofre > cálcio. A ordem decrescente dos macronutrientes acumulados pela planta foi: potássio > nitrogênio > magnésio > cálcio > fósforo > enxofre. O período de maior demanda para a maioria dos macronutrientes foi dos 29 aos 43 dias após o transplante (DAT). Para produção, observou-se efeito quadrático para as doses de composto com máxima produtividade com 52 t ha-1. A adubação potássica em cobertura não proporcionou aumento na produção, indicando que a adubação potássica de plantio foi suficiente para suprir a demanda de potássio / The aim of this work was to evaluate the response of beet in function organic compost levels and potassium fertilization, and their effects on soil properties. The experiment was conducted at São Manuel Experimental Farm (FCA/UNESP), in São Manuel- SP, with 10 treatments in factorial scheme 5x2, and randomized complete blocks design, with four replications. Five compost levels (0, 20, 40, 60 and 80 t ha-1) were evaluated in the presence (60 kg ha-1 of K2O) and absence of potassium fertilization in coverage. For all treatments was done fertilization with nitrogen, phosphorus and potassium at planting, according to soil analysis. The characteristics evaluated were: soil chemical properties during the cycle, vegetative characteristics (height; number of leaves; fresh and dry weight of shoot, root and total plant; and leaf area) during the cycle, accumulation and exportation of macronutrients (nitrogen, phosphorus, potassium, calcium, magnesium and sulfur) and production (fresh weight, yield, root length and diameter). The organic compost levels provide positive effects on the soil chemical properties during all periods evaluated. The order of nutrients exported by the beet roots was: potassium > nitrogen > phosphorous > magnesium > sulfur > calcium. The order of nutrients accumulated in the beet plant was: potassium> nitrogen> magnesium > calcium > phosphorus > sulfur. The period with the biggest demand for most of macronutrients was from 29 to 43 days after transplantation (DAT). For production, it was observed quadratic effect for compost levels with the highest yield with 52 t ha-1. Potassium fertilization in coverage did not provide increase in production, indicating that potassium fertilization at planting was sufficient to support the demand of potassium for beets
12

Efeito do composto orgânico e adubação potássica em atributos do solo e da beterraba /

Magro, Felipe Oliveira, 1984- January 2012 (has links)
Orientador: Antonio Ismael Inácio Cardoso / Coorientador: Dirceu Maximino Fernandes / Banca: Luiz Antonio Augusto Gomes / Banca: Arthur Bernardes Cecilio Filho / Banca: Luis Felipe Villani Purquerio / Banca: Roberto Lyra Villas Bôas / Resumo: O objetivo deste trabalho foi avaliar a resposta da beterraba à doses de composto orgânico e adubação potássica em cobertura, e o efeito destes em atributos do solo. Foi realizado um experimento na Fazenda Experimental São Manuel (FCA/UNESP), localizada em São Manuel-SP, com 10 tratamentos, em esquema fatorial 5 x 2, e delineamento experimental em blocos ao acaso, com quatro repetições. Foram avaliadas cinco doses de composto orgânico (0; 20; 40; 60 e 80 t ha-1) na presença (60 kg ha-1 de K2O) e ausência da adubação potássica em cobertura. Para todos os tratamentos foi feita adubação com nitrogênio, fósforo e potássio no plantio, de acordo com a análise de solo. As características avaliadas foram: propriedades químicas do solo ao longo do ciclo, características vegetativas (altura; número de folhas; massa fresca e seca da parte aérea, raiz e da planta e área foliar) ao longo do ciclo, acúmulo e exportação de macronutrientes (nitrogênio, fósforo, potássio, cálcio, magnésio e enxofre) e produção (massa média, produtividade, diâmetro e comprimento das raízes). As doses de composto orgânico proporcionaram efeito positivo nas propriedades químicas do solo durante todas as épocas avaliadas. A ordem decrescente dos macronutrientes exportados pelas raízes de beterraba foi: potássio > nitrogênio > fósforo > magnésio > enxofre > cálcio. A ordem decrescente dos macronutrientes acumulados pela planta foi: potássio > nitrogênio > magnésio > cálcio > fósforo > enxofre. O período de maior demanda para a maioria dos macronutrientes foi dos 29 aos 43 dias após o transplante (DAT). Para produção, observou-se efeito quadrático para as doses de composto com máxima produtividade com 52 t ha-1. A adubação potássica em cobertura não proporcionou aumento na produção, indicando que a adubação potássica de plantio foi suficiente para suprir a demanda de potássio / Abstract: The aim of this work was to evaluate the response of beet in function organic compost levels and potassium fertilization, and their effects on soil properties. The experiment was conducted at São Manuel Experimental Farm (FCA/UNESP), in São Manuel- SP, with 10 treatments in factorial scheme 5x2, and randomized complete blocks design, with four replications. Five compost levels (0, 20, 40, 60 and 80 t ha-1) were evaluated in the presence (60 kg ha-1 of K2O) and absence of potassium fertilization in coverage. For all treatments was done fertilization with nitrogen, phosphorus and potassium at planting, according to soil analysis. The characteristics evaluated were: soil chemical properties during the cycle, vegetative characteristics (height; number of leaves; fresh and dry weight of shoot, root and total plant; and leaf area) during the cycle, accumulation and exportation of macronutrients (nitrogen, phosphorus, potassium, calcium, magnesium and sulfur) and production (fresh weight, yield, root length and diameter). The organic compost levels provide positive effects on the soil chemical properties during all periods evaluated. The order of nutrients exported by the beet roots was: potassium > nitrogen > phosphorous > magnesium > sulfur > calcium. The order of nutrients accumulated in the beet plant was: potassium> nitrogen> magnesium > calcium > phosphorus > sulfur. The period with the biggest demand for most of macronutrients was from 29 to 43 days after transplantation (DAT). For production, it was observed quadratic effect for compost levels with the highest yield with 52 t ha-1. Potassium fertilization in coverage did not provide increase in production, indicating that potassium fertilization at planting was sufficient to support the demand of potassium for beets / Doutor
13

Moisture stress conditioning, potassium nutrition, and tolerance of Salvia splendens 'Bonfire' to moisture stress

Eakes, Donald Joseph January 1989 (has links)
The objective of this study was to determine the leaf water relations, gas exchange, and growth of the bedding plant salvia Salvia splendens 'Bonfire‘ as influenced by moisture stress conditioning (MSC - exposing plants to 4 sublethal dry-down cycles) and potassium (K) nutrition. Plants were fertilized with one of six K rates: 25, 75, 150, 300, 450, and 600 ppm as KCl in experiment one. Seven weeks after seeding plants were subjected to MSC. MSC and increasing K rate resulted in osmotic adjustment and increased cellular turgor potentials. Foliar K content increased as osmotic potentials decreased due to treatment. Although there was no interaction, MSC and high K rates both reduced transpiration (E), leaf conductance (g₁), and daily gravimetric water loss during well watered conditions. Greatest shoot dry weight occurred for plants grown with 300 ppm K and no-MSC. Gas exchange of salvia as influenced by MSC during the onset of moisture stress was determined in experiment two. On day one following final irrigation, MSC plants had lower mid-day E, g₁, hourly gravimetric water loss per unit leaf area, and net photosynthesis (Pn) compared to controls, despite no differences in leaf water potential (ψ₁). Percentage of stomatal inhibition of Pn (SI) was greater for MSC plants than controls with no differences in mesophyllic resistance to CO₂ (r<sub>m</sub>). On day two, MSC plants had greater Pn, E, g₁, and hourly gravimetric water loss per unit leaf area, while SI and r<sub>m</sub> were lower than controls. MSC plants maintained positive Pn rates and turgor to lower ψ₁ than control plants. Water use efficiency (WUE) estimates for MSC plants were greater than for controls. Salvia plants were fertilized with 75, 300, or 600 ppm K to determine the influence of K rate on gas exchange during the onset of moisture stress in a third experiment. On day one following final irrigation, plants grown with K rates of 300 and 600 ppm had lower E, g₁, hourly gravimetric water loss per unit leaf area, and Pn compared to 75 ppm K plants. On day two, 600 ppm K plants had greater Pn, E, and g₁ as the experiment was terminated compared to plants grown with 75 ppm K, although ψ₁ was similar. Potassium rate had little affect on WUE. / Ph. D.

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