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Composi??o química de capim-tanzania adubado com nitrogênio e fósforo
Sousa, Ronaldo Silva;Pires, Aureliano José Vieira;Carvalho, Gleidson Giordano Pinto de;Silva, Fabiano Ferreira da;Magalh?es, Albertí Ferreira;Veloso, Cristina Mattos;
Revista Brasileira de Zootecnia , 2010, DOI: 10.1590/S1516-35982010000600006
Abstract: it was evaluated in this work the contents of dry matter (dm), crude protein (cp), neutral detergent fiber (ndf), total digestible nutrients (tdn), calcium (ca), phosphorus (p) and magnesium (mg) in the aerial section of the tanzania grass (panicum maximum), fertilized with nitrogen and phosphorus during the summer and autumn. the experimental design was complete randomized, with a 4 × 3 factorial scheme, and four n rates (0, 100, 200, and 300 kg/ha/year), and three pentoxide diphosphorus (p2o5) rates (0, 50, and 100 kg/ha/year), with three replicates. three cuts were made at 40 cm of the soil, every 35 days. after each cut, the fertilization was accomplished, and p2o5 was applied only once on the uniformed cut and n was parceled in three times. nitrogen rates did not affect contents of magnesium and they reduced contents of dry matter, calcium and phosphorus, while phosphate fertilization increased levels of phosphorus. fertilization had a quadratic effect on the levels of crude protein, neutral detergent fiber, and total digestible nutrients providing a forage of better quality as doses increased, mainly nitrogen doses. in the studied edaphoclimathic conditions, it is recommend fertilization of tanzania grass with 300 kg of n/ha and 100 kg of p2o5/ha.
Macronutrientes em folhas diagnósticas do capim-tanzania adubado com nitrogênio e cálcio
Silveira, Cristiane Prezotto;Monteiro, Francisco Antonio;
Revista Brasileira de Zootecnia , 2010, DOI: 10.1590/S1516-35982010000400006
Abstract: an experiment under greenhouse conditions was carried out with tanzania guineagrass supplied with combined rates of nitrogen and calcium in nutrient solutions during the spring season. a randomized block design was used, with four replicates, in an incomplete 52 factorial scheme with five nitrogen rates (2; 9; 16; 23 e 30 mmol l-1) and five calcium rates (0.50; 1.75; 3.00; 4.25 e 5.50 mmol l-1) resulting in 13 nitrogen:calcium combinations (mmol l-1): 2:0.50; 2:3.00; 2:5.50; 9:1.75; 9:4.25; 16:0.50; 16:3.00; 16:5.50; 23:1.75; 23:4.25; 30:0.50; 30:3.00 and 30:5.50. macronutrient concentrations were determined in the two recently expanded leaf blades (diagnostic leaves) collected in the three harvests of tanzania guineagrass. the results showed that, in the first harvest of the plants, calcium rates did not interact with nitrogen for any of the nutritional traits, except for sulphur concentration in the diagnostic leaves. the interaction nitrogen × calcium was significant for concentrations of calcium and sulphur in the diagnostic leaves at the second and third samplings of the grass. nitrogen rates and, not calcium rates, are determinant for nitrogen, phosphorus, and potassium concentrations in the diagnostic leaves of tanzania guineagrass. the concentration of calcium at the first harvest of the grass depends only on the supply of this nutrient. concentration of magnesium in plant tissue decreases as nitrogen or calcium supply increases. reduction of calcium to 40% of that one used in the nutrient solution does not reduce nutritional parameters of this grass, even with the supply of high nitrogen rate.
Características do pasto de capim-tanzania adubado com nitrogênio no final do ver?o
Euclides, Valéria Pacheco Batista;Macedo, Manuel Cláudio Motta;Zimmer, Ademir Hugo;Medeiros, Rodrigo Narciso de;Oliveira, Marcelo Paschoal de;
Pesquisa Agropecuária Brasileira , 2007, DOI: 10.1590/S0100-204X2007000800017
Abstract: the objective of this work was to evaluate the forage yield, morphological components and nutritive value of panicum maximum cv. tanzania, with a second application of nitrogen fertilizer in march, at the end of summer. maintenance fertilizer was 50, 17.5 and 33.2 kg ha-1 of n, p and k, respectively, applied annually, in november. besides, in half of the area, an additional 50 kg ha-1 of n was applied, in march. the treatments were tanzania pasture with two levels of nitrogen fertilization, 50 and 100 kg ha-1. the paddocks were divided in six plots, and submitted to a rotational grazing. forage yield, percentages of the morphological components and nutritive value were evaluated. the accumulation rates of green dry matter and leaf dry matter, mainly in autumn, were greater for pastures that received 50 kg ha-1 of n additional in march. there were increases in the percentages of crude protein and in vitro organic matter digestibility, before and after grazing, after nitrogen application. the fertilization with 50 kg ha-1 per year of n was enough to keep forage yield stable during three years under grazing. the fertilization with additional 50 kg ha-1 per year of n, in march, decreased seasonal dependence of forage production, besides yielding forage with a higher nutritive value during autumn.
Sistema radicular do capim-tanzania adubado com potássio e magnésio
Monteiro, Francisco Antonio;Consolmagno Neto, Dylnei;
Revista Brasileira de Zootecnia , 2008, DOI: 10.1590/S1516-35982008000500005
Abstract: a greenhouse experiment was carried out during the spring 2004 aiming to evaluate panicum maximum cv. tanzania root system as related to the combined supply of k and mg in nutrient solutions. a randomized block design was used, with four replications, in an incomplete 52 factorial experiment with 13 combinations between k and mg fertilization rates, in mmol/l: 0.4k/0.05mg; 0.4k/1.35mg; 0.4k/2.65mg; 3.2k/0.70mg; 3.2k/2.00mg; 6.0k/0.05mg; 6.0k/1.35mg; 6.0k/2.65mg; 8.8k/0.70mg; 8.8k/2.00mg; 11.6k/0.05mg; 11.6k/1.35mg, and 11.6k/2.65mg. roots were collected after the second harvest of the plants, by washing with tap and deionized water and using 0.25 and 1.00 mm screens. potassium and magnesium rates combinations highly influenced root dry weight, specific root length and surface, and root k concentration. increasing mg rates also increased root surface, but decreased calcium concentration in the grass roots. maximum responses of tanzania guineagrass roots were found when k was supplied between 6.0 and 8.8 mmol/l and mg between 1.4 and 2.0 mmol/l. root k concentration ranged between 35 and 53% and root mg concentration about 20% to the total concentration of potassium, magnesium and calcium in the grass roots.
ACUMULA O DE NUTRIENTES NO LIMBO FOLIAR DE GUANDU E ESTILOSANTES NUTRIENT ACCUMULATION IN PIGEON PEA AND STYLO LEAF BLADE
Pedro Marques da Silveira,Ant?nio Joaquim Braga Pereira Braz,Huberto José Kliemann,Francisco José Pfeilsticker Zimmermann
Pesquisa Agropecuária Tropical , 2007, DOI: 10.5216/pat.v35i3.2213
Abstract: Guandu (Cajanus cajan) e estilosantes (Stylosanthes guianensis var. vulgaris cv. Mineir o) s o duas leguminosas cultivadas em solos dos cerrados da regi o Centro-Oeste, utilizadas para aduba o verde, produ o de sementes e pastoreio. O objetivo deste trabalho foi avaliar a acumula o dos nutrientes N, P, K, Ca, Mg, Zn, Cu, Mn e Fe no limbo foliar dessas leguminosas, em fun o dos dias após emergência (DAE) da planta. O experimento foi conduzido em Latossolo Vermelho distrófico, na Embrapa Arroz e Feij o, em Santo Ant nio de Goiás, GO. Os tratamentos foram distribuídos em blocos ao acaso, com quatro repeti es. As parcelas tiveram 6,0 m de largura e 20,0 m de comprimento. A aduba o de plantio foi de 400 kg ha-1 da fórmula comercial 5-30-15. O plantio foi realizado em dezembro de 2001. Durante o ciclo das culturas, foram tomadas nove amostras aleatórias de limbos foliares para análise foliar. De posse da massa da matéria seca e da concentra o dos nutrientes, calcularam-se as suas acumula es no limbo foliar das duas leguminosas. Fez-se o ajuste dos dados de acumula o do nutriente (Y) em fun o dos dias após a emergência (X) por um modelo exponencial quadrático Y = a exp(bx + cx2). O guandu produziu mais matéria seca e, de modo geral, teve maior acumula o de nutrientes que o estilosantes, até 98 dias de idade. Dentre os macronutrientes, as maiores acumula es foram de N e as menores de P. O micronutriente de maior acumula o no limbo foliar das duas leguminosas foi Fe, e o de menor acumula o, Cu. PALAVRAS-CHAVE: Leguminosas; conteúdo de nutrientes; nutri o mineral; Cajanus cajan; Stylosanthes guyanensis. Pigeon pea (Cajanus cajan) and stylo plants (Stylosanthes guianensis var. vulgaris cv. Mineir o) are two legumes cultivated in cerrado soils of central-west Brazil and cultivates for green manure, seed production, and pasture. The objective of this study was to evaluate accumulation of N, P, K, Ca, Mg, Zn, Cu, Mn, and Fe in leaf blades as a function of days after emergence. The experiment was developed in a dystrophic Oxisol at Embrapa Rice and Bean Research Center, in Santo Ant nio de Goiás, Goiás State, Brazil. The treatments were arranged in a completely randomized block design with four replications. Plot size was 6.0 m wide and 20.0 m long. Planting fertilization was 400 kg ha-1 of a 5-30-15 formula. Sowing was done in December 2001. During crop growth, nine random leaf blades samples were collected on the different days after sowing for chemical analysis. Nutrient accumulation (Y) was determined and data were adjusted as a function of days afte
Produ??o de massa seca, eficiência e recupera??o do nitrogênio e enxofre pelo capim-tanzania adubado com nitrogênio, potássio e enxofre
Costa, Kátia Aparecida de Pinho;Fran?a, Aldi Fernandes de Souza;Oliveira, Itamar Pereira de;Monteiro, Francisco Antonio;Barigossi, José Alexandre Freitas;
Ciência e Agrotecnologia , 2005, DOI: 10.1590/S1413-70542005000300013
Abstract: the experiment was carried out in a dark red latosol at fazenda modelo, federal university of goiás, in order to evaluate the effect of n:k rates with the use of s in the production of dry mass of tanzania grass. also, the efficiency of n and s conversion and recovery in dry mass were evaluated. rates of 150, 300 and 450 kg/ha of n:k aditioning 20, 40 and 60 kg/ha of s were applied as broadcast covering. the experimental design was a randomized complete blocks in a 3x3 factorial with three replications. the forage evaluation period was six months and the samples were collected at 30 cm-plant height. the highest productions of dry mass of tanzania grass were obtained with applications of greater n:k and s rates. the highest efficiencies of nitrogen and sulfur conversions were verified with applications of the lowest n:k and s rates, with no significant differences in concentration of these nutrients in the plant tissues as their rate of application increased. higher s contensts in leaf tissue and relative recovery of n and s were observed by applying 450 kg/ha n:k and 60 kg/ha of s.
Eficiência biológica e econ?mica de pasto de capim-tanzania adubado com nitrogênio no final do ver?o
Euclides, Valéria Pacheco Batista;Costa, Fernando Paim;Macedo, Manuel Cláudio Motta;Flores, Renata;Oliveira, Marcelo Paschoal de;
Pesquisa Agropecuária Brasileira , 2007, DOI: 10.1590/S0100-204X2007000900017
Abstract: the objective of the work was to estimate animal live weight gain, the pasture carrying capacity, and the bioeconomic efficiency of panicum maximum, cultivar tanzania pastures, with a second application of nitrogen fertilizer in the end of summer (march). maintenance fertilizer was 50, 17.5 and 33.2 kg ha-1 of n, p and k, respectively, applied annually in november. besides, in half of the area, an additional 50 kg ha-1 of n was applied in march. treatments were tanzania pastures with two levels of nitrogen fertilization, 50 and 100 kg ha-1. the paddocks were submitted to a rotational grazing. four steers were kept in each paddock, and additional steers were allocated and removed to assure similar postgrazing residues. there was no effect of n fertlization on average daily gain. however, the pasture fertilized with 100 kg ha-1 de n (1,8 ua ha-1) resulted in greater carrying capacity and productivity (780 kg ha-1 of liveweight per year) than that observed in the one fertilized with 50 kg ha-1 de n (1,5 ua ha-1) and productivity of 690 kg ha-1 per year of liveweight, on average. the efficiency of n conversion into animal product was 1.8 kg lw ha-1 for each additional kilogram of n applied. additional n fertilization in march, is a bioeconomically viable alternative for producing sustainable beef.
Raz o folha/haste e composi o bromatológica da rebrota de estilosantes Campo Grande em cinco idades de corte = Leaf-to-stem ratio and bromatological characteristics of Campo- Grande stylo regrowth at five cutting ages
Raniel Lustosa de Moura,Maria do Perpétuo Socorro Cortez Bona do Nascimento,Marc?nio Martins Rodrigues,Maria Elizabete Oliveira
Acta Scientiarum : Animal Sciences , 2011,
Abstract: Objetivou-se avaliar a composi o bromatológica e a raz o folha/haste do estilosantes Campo Grande, em cinco idades de rebrota com e sem aduba o fosfatada. Adotou-se o delineamento experimental em blocos ao acaso, com quatro repeti es, em esquema fatorial 2 x 5 dois níveis de fósforo (com e sem) e cinco idades de corte (30, 35, 40, 45 e 50 dias). O fósforo foi aplicado como superfosfato simples, equivalente a 50 kg ha-1 de P2O5. A raz o folha/haste (F/H) e os porcentuais de proteína bruta (PB) decresceram com o aumento da idade de rebrota, com e sem aduba o fosfatada. A produtividade de proteínabruta (PPB), com aduba o fosfatada, foi linear crescente e sem, foi quadrática, decrescendo entre 45 e 50 dias de rebrota. Os porcentuais de matéria seca (MS) e fibra em detergente neutro (FDN) cresceram com o aumento da idade de rebrota. O porcentual da fibra em detergente ácido (FDA) apresentou comportamento quadrático, com decréscimo nas idades de 45 e 50 dias. A aduba o fosfatada n o tem efeito sobre a raz o F/H, PB, MS, FDN e FDA de estilosantes Campo Grande. As idades de rebrota de 30 a 50 dias com ou sem aduba o fosfatada têm efeito mínimo sobre a composi o bromatológica do estilosantes Campo Grande. The aim of this research study was to evaluate the bromatological composition and leaf-to-stem ratio of Campo-Grande stylo, at five regrowth ages, with and without phosphorus. The investigation was carried out in a randomized blocks experimental design, with four replications in a 2 x 5 factorial arrangement – two levels of phosphorus (with or without) and five cutting ages (30, 35, 40, 45 and 50 days). Phosphorus was applied as a single superphosphate, equivalent to 50 kg ha-1 P2O5. The leaf-to-stem ratio (L/S) and the percentage of crude protein (CP) decreased with increasing age of regrowth, with and without phosphorus fertilization. Crude protein yield (CPY) with phosphorus fertilization increased linearly; yield without fertilization was quadratic, decreasing between 45 and 50 days of regrowth. The percentages of dry matter (DM) and neutral detergent fiber (NDF) increased with regrowth age. The percentage ofacid detergent fiber (ADF) followed a quadratic trend, decreasing at the ages of 45 and 50 days. Phosphorus fertilization had no effect on L/S, CP, DM, NDF and ADF of Campo- Grande stylo. The age of regrowth of 30 and 50 days have minimal effect on the bromatological composition of Campo-Grande stylo.
Morfogênese e produ??o de biomassa do capim-tanzania adubado com nitrogênio e cálcio
Silveira, Cristiane Prezotto;Monteiro, Francisco Antonio;
Revista Brasileira de Zootecnia , 2007, DOI: 10.1590/S1516-35982007000200009
Abstract: the objective of this study was to evaluate grass responses to combined rates of nitrogen and calcium. measured response variables included leaf number, tiller number, leaf area, and dm yield. tanzaniagrass was grown in nutrient solution with ground quartz as substrate, in a greenhouse experiment. the experiment was carried out in randomized block design, with four replications. a fractionated 52 factorial was used, with combinations of five nitrogen rates (2, 9, 16, 23, and 30 mmol l-1) and five calcium rates (0.50, 1.75, 3.00, 4.25, and 5.50 mmol l-1). three harvests were performed, the first one 39 days after seedlings transplanting, the second one 30 days after the first harvest, and the third one 28 days after the second harvest. calcium rates did not interact with the nitrogen rates for the productive variables in the first growth of this grass. the number of tillers and leaves depended only on nitrogen rates. combination of nitrogen and calcium rates was necessary for tanzaniagrass leaf area at the third growth, and for the shoot biomass at the second and third growths. maximum productive responses of this forage were reached with the minimum supply of nitrogen of 23 mmol l-1. the use of calcium at rate not inferior to 2 mmol l-1 did not reduce productive variables of this grass, even with the supply of high nitrogen rate.
RENTABILIDADE EFETIVA E RENTABILIDADE TOTAL DO CULTIVO DE MILHO ADUBADO COM LODO DE ESGOTO
Núria Rosa Gagliardi Quintana,Wanderley José de Melo,Maristela Sim?es do Carmo
Nucleus , 2012,
Abstract: : In this study, we calculated effective and total economic rentability about corn production fertilized with sewage sludge. The corn was cultivated on a minimal tillage treatment in a field experiment. The trial was carried out during 2002/2003, set up on an oxisol area of 1/16 ha The farming operations were detailed to specify machinery, equipment, manpower, materials consumed and hours worked. Operating costs, calculated accordingto the methodology of the IEA, were subtracted from revEste trabalho teve como objetivo calcular as rentabilidades efetiva e total do cultivo de milho adubado com lodo de esgoto. O experimento, cuja produtividade média foi de 375,38 kg, foi instalado no ano agrícola 2002/2003, em Latossolo Vermelho eutroférrico e conduzido com milho AGROMEN 3150, através de cultivo mínimo. A dimens o da área experimental estudada foi de 625m2. As opera es de cultivo foram detalhadas para especificar máquinas, equipamentos, m o-de-obra, insumos consumidos e horas trabalhadas. Os custos operacionais, calculados conforme a metodologia do IEA, foram subtraídos da receita, resultando nas rentabilidades. Os resultados de rentabilidade efetiva (R$55,80) e total (R$40,70) apontam que a aplica o de lodo de esgoto é economicamente rentável.
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