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| Registros recuperados: 40 | |
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| Gomes Junior, Francisco Guilhien; ESALQ - USP; Sá, Marco Eustáquio de; UNESP; Muraishi, Cid Tacaoca; UNESP. |
| A aplicação de N em cobertura é indispensável para a obtenção de altas produtividades do feijoeiro e estudos de respostas ao fertilizante em condições de semeadura direta e preparo convencional do solo ainda consistem numa necessidade fundamental. Assim, a pesquisa teve como objetivo avaliar o efeito da aplicação de N e a produtividade do feijoeiro em sistema de semeadura direta e de preparo convencional do solo. O delineamento experimental foi o de blocos casualizados em esquema fatorial (2x8+1) com quatro repetições. Os tratamentos constituíram-se da combinação das doses de 40 e 80 kg ha-1 de N aplicadas em oito épocas do estádio V4 do desenvolvimento vegetativo (V4-3, V4-4, V4-5, V4-6, V4-7, V4-8, V4-9 e V4-10), além da testemunha sem N em cobertura. O... |
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Palavras-chave: 5.01.03.05-9 Melhoramento Vegetal Phaseolus vulgaris L.; Cobertura morta; Adubo nitrogenado; Fenologia Phaseolus vulgaris L.; Mulching; Nitrogen fertilizer; Phenology. |
| Ano: 2008 |
URL: http://periodicos.uem.br/ojs/index.php/ActaSciAgron/article/view/5967 |
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| Teixeira, Cícero Monti; Empresa de Pesquisa Agropecuária de Minas Gerais; Carvalho, Gabriel José de; Universidade Federal de Lavras; Silva, Carlos Alberto; Universidade Federal de Lavras; Andrade, Messias José Bastos de; Universidade Federal de Lavras; Paes, José Mauro Valente; Empresa de Pesquisa Agropecuária de Minas Gerais. |
| O objetivo foi avaliar o efeito das palhadas de milheto (Pennisetum typhoides (Burm.) Stapf) e milheto + feijão-de-porco (Canavalia ensiformes (L.) DC.) e diferentes doses de nitrogênio, na nutrição mineral do feijoeiro. O delineamento foi em blocos casualizados, com quatro repetições, em esquema de parcelas subdivididas, em Latossolo Vermelho, em plantio direto. As parcelas foram constituídas pelas palhadas e as subparcelas por um fatorial 2 x 4 + 1, representado por duas doses de N na semeadura (30 e 60 kg ha-1) e quatro em cobertura (0, 40, 80 e 120 kg ha-1), mais um tratamento adicional, correspondente a 30 kg ha-1 de N na semeadura, sem cobertura, com inoculação das sementes com Rhizobium tropici e aplicação foliar de Co e Mo. A palhada de milheto +... |
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Palavras-chave: 5.01.00.00-9 plantas de cobertura; Sistema plantio direto; Consórcio gramínea x leguminosa; Adubação nitrogenada; Fixação biológica de nitrogênio 5.01.01.03-0 cover crops; No-till; Grassy x leguminous intercropping; Nitrogen fertilizer; Biology nitrogen fixation. |
| Ano: 2010 |
URL: http://periodicos.uem.br/ojs/index.php/ActaSciAgron/article/view/4392 |
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| Gomes Junior, Francisco Guilhien; ESALQ/USP; Sá, Marcos Eustáquio de; FAE/UNESP; Valério Filho, Walter Veriano; FAE/UNESP. |
| O adequado suprimento de N é primordial para se obter alta produtividade de sementes de feijão, entretanto, as respostas a esse nutriente, em sistema de plantio direto, podem variar em função da espécie e quantidade de palha. O objetivo do trabalho foi avaliar a resposta do feijoeiro à aplicação de N, em sistema de plantio direto, sobre palhada de milho, milheto e braquiária. Foram realizados três experimentos, um para cada espécie de gramínea. O delineamento experimental foi o de blocos casualizados disposto em esquema fatorial 5x2x2, correspondente a cinco doses de N (0, 30, 60, 90, 120 kg ha-1) aplicadas em duas épocas da fase vegetativa (3ª e 6ª folha trifoliolada) e duas cultivares (IPR Juriti e Pérola), com quatro repetições. A cultivar IPR Juriti... |
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Palavras-chave: 5.01.00.00-9 Agronomia Phaseolus vulgaris L.; Palhada adubação nitrogenada; Fenologia; Rendimento de sementes 5.01.03.00-8 Fitotecnia Phaseolus vulgaris L.; Mulching; Nitrogen fertilizer; Phenology; Seed yield. |
| Ano: 2008 |
URL: http://periodicos.uem.br/ojs/index.php/ActaSciAgron/article/view/3549 |
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| Mesquita,Geisa Lima; Zambrosi,Fernando César Bachiega; Cantarella,Heitor. |
| ABSTRACT We propose an approach for assessing the efficiency of coating materials on controlling nitrogen (N) availability to plants. It is based on the use of coated and soluble urea (UR) applied to corn over 3 growing cycles, as follows: coated UR with longevity of 2 (UR-2m) or 4 months (UR-4m) with application of 900 mg N∙pot−1 at the beginning of the experiment, soluble UR with a split application of 900 mg N∙pot−1 (300 mg N∙pot−1 per growing cycle, UR-3x), soluble UR with a sole application of 900 mg N∙pot−1 at the beginning of the experiment (UR-1x), and a control treatment. At the end of each growing cycle, shoots were harvested to estimate N provision by the UR by quantifying dry matter (DM) and N uptake. In the first cycle, UR-2m and UR-4m... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Coating; Fertilizer efficiency; Nitrogen fertilizer; Nutrient uptake. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052017000200311 |
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| Araújo,Juliano Ribeiro; Ramalho,Magno Antonio Patto; Bruzi,Adriano Teodoro; Abreu,Ângela de Fátima Barbosa. |
| The objective of this study was to verify the response of dry matter accumulation in bean lines (Phaseolus vulgaris L.) to different levels of nitrogen fertilizers. Six genotypes ('BRSMG Majestoso', 'Pérola', MA-I-18.13, 'Ouro Negro', 'BRSMG Talismã', and MA-I-2.5) were evaluated in Lavras, testing three N levels (0, 60, and 120 kg/ha) and using ammonium sulphate as N source. The experimental design adopted was the randomized block design in a 6 x 3 factorial structure with three replications and the plots were composed of five 5-m rows. The seeds were sown in November 2005 and July 2006. Total dry mass of five competitive plants was evaluated after 35 days from sowing, harvested from a pre-determined place in the useful area of the plots. This process was... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Nitrogen fertilizer; Phenology; Differential response; Phaseolus vulgaris. |
| Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-70542009000400007 |
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| Debaene,Guillaume; Pikuła,Dorota; Niedźwiecki,Jacek. |
| The objective of this research was to investigate the effects of a long-term experiment on soil spectral properties and to develop prediction models of these properties (soil organic carbon (SOC), N, pH, Hh, P2O5, K2O, Ca, Mg, K, and Na content) from texturally homogeneous samples (loamy sand). To this aim, chemometric techniques, such as partial least square (PLS) regression and support vector machine (SVM) classification, were used. Our results show that visible and near infrared spectroscopy (VIS-NIRS) is suitable for the prediction of properties of texturally homogeneous samples. The effects of fertilizer applications were sufficient to modify the soil chemical composition to a range suitable for using VIS-NIRS for calibration and modeling purposes.... |
| Tipo: Journal article |
Palavras-chave: Manure; Near-infrared spectroscopy; Nitrogen fertilizer; Partial least square regression; Soil organic carbon; Support Vector Machine. |
| Ano: 2014 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-16202014000100003 |
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| Oliveira Filho,Jair da C.; Oliveira,Rubens A. de; Oliveira,Ednaldo M. de; Cecon,Paulo R.; Martins,Carlos E.. |
| The objective of this study was to evaluate the effects of the application of different water depths and nitrogen and potassium doses in the quality of Tanzania grass, in the southern of the state of Tocantins. The experiment was conducted on strips of traditional sprinklers, and used, as treatments, a mixture of fertilizer combinations of N and K2O always in the ratio of 1 N:0.8 K2O. This study determined throughout the experiment: plant height (PH), the crude protein (CP) and neutral detergent fiber (NDF). The highest plant height obtained was 132.4 cm, with a fertilizer dose of 691.71 kg ha-1 in the proportion of N:0.8 K2O, in other words, 384.28 kg ha-1 of N and 307.43 kg ha-1 of K2O, and water depth of 80% of the ETc. The highest crude protein content... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Nitrogen fertilizer; Irrigated pasture; Panicum maximum. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162012000400007 |
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| Flores,Rilner A.; Urquiaga,Segundo; Alves,Bruno J. R.; Collier,Leonardo S.; Boddey,Robert M.. |
| The objective of this study was to evaluate the performance of two genotypes of elephant grass, fertilized with and without N, for biomass production for energy use under the edaphoclimatic conditions of the Cerrado. The genotypes Roxo and Paraíso, grown in a field experiment in a Latosol in the Cerrado region were evaluated for biomass yield, nitrogen accumulation, C:N and stem:leaf ratios, fibre, ash and P and K contents and calorific value. The accumulated dry biomass ranged from 30 to 42 Mg ha-1 and showed no response to nitrogen fertilization with the lowest biomass obtained by the genotype Paraíso and the highest by Roxo. The total N accumulation followed the same pattern as for dry matter, ranging from 347 to 539 kg N ha-1. C:N and stem:leaf ratio... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Pennisetum purpureum; Bioenergy; Nitrogen fertilizer. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162012000500003 |
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| Luz,José MQ; Queiroz,Angélica A; Oliveira,Roberta C. |
| A alta resposta da batateira à adição de nutrientes ao solo requer atenção especial aos aspectos relacionados à fertilidade, especialmente o nitrogênio (N), por ser o nutriente que ocasiona maior impacto na produtividade. Com o objetivo de identificar o teor crítico de N na cultura da batata em função das suas doses, realizou-se um experimento em Perdizes-MG, entre os meses de julho e novembro de 2010 com a cultivar Asterix. O delineamento experimental foi de blocos ao acaso, com cinco doses de N (0, 70, 140, 210 e 280 kg ha-1) e quatro repetições. As mesmas foram parceladas, sendo 20% da dose aplicada no momento do plantio e 80% em cobertura, juntamente com a operação da amontoa, 30 dias após o plantio. O restante da adubação foi composta por 400 kg ha-1... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Solanum tuberosum; Adubação nitrogenada; Produtividade; Teor de nitrogênio foliar; Solanum tuberosum; Nitrogen fertilizer; Productivity; Nitrogen leaf level. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-05362014000200225 |
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| ELHAKEM,A.H.; ABD EL-SALAM,M.M.. |
| ABSTRACT: This study evaluates the effect of urea on growth of herbicide-treated maize and its accumulation in the soil. When the seedlings were 15 days old, the plots were divided into five groups. One group served as control, two received treatments with metolachlor and isoproturon at the dose of 1.5 kg ha-1 and 2.5 L ha-1, respectively. The two remaining groups received the same dose of herbicide along with urea added at a rate of 129 kg ha-1. The application of the two herbicides appeared to cause a significant decrease in shoot dry weight, photosynthetic pigments, d-aminolevulinate dehydratase enzyme [ALA-D, EC 4.2.1.24] and total soluble carbohydrates of the maize plants. The application of urea appeared to alleviate the effects of both herbicides on... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Maize; Soil accumulation; Nitrogen fertilizer. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582018000100308 |
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| Huang, Wen-Yuan. |
| Nitrogen applied before planting is more vulnerable to loss to the environment than nitrogen applied during the growing season, but the growing season application can increase the risk of lower yields caused by adverse weather that prohibits farmers to complete N application. An expected utility framework is used to illustrate the potential economic benefit of insurance for a farmer to reduce this risk of cost. An expected-value variance analysis is used to illustrate the potential benefit of insurance to Iowa corn growers who apply N fertilizer only during the growing season. |
| Tipo: Journal Article |
Palavras-chave: Insurance; Nitrogen fertilizer; Application timings; Risk and Uncertainty. |
| Ano: 2002 |
URL: http://purl.umn.edu/15520 |
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| Registros recuperados: 40 | |
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