|
|
|
| Registros recuperados: 16 | |
|
|
| Faria,Letícia de Abreu; Luz,Pedro Henrique de Cerqueira; Macedo,Felipe Barros; Tonetti,Paulo Sergio; Ferraz,Marcos Roberto; Mazza,Jairo Antônio; Vitti,Godofredo Cesar. |
| ABSTRACT High contents of plant-available selenium in the soil in the form of selenate, resulting from natural or anthropogenic action, jeopardizes agricultural areas and requires research for solutions to establish or re-establish agricultural or livestock operation, avoiding the risk of poisoning of plants, animals and humans. The purpose was to evaluate sulfur sources in the form of sulfate, e.g., ammonium sulfate, calcium sulfate, ferric sulfate, in the remediation of tropical soils anthropogenically contaminated with Se under the tropical forage grass Brachiaria brizantha (Hochst. ex A. Rich.) Stapf cv. Marandu. More clayey soils are less able to supply plants with Se, which influences the effects of S sources, but it was found that high soil Se... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Contamination; Selenate; Remediation; Toxicity. |
| Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832015000601814 |
| |
|
|
| Faria,Letícia de Abreu; Luz,Pedro Henrique de Cerqueira; Rodrigues,Rosane Cláudia; Herling,Valdo Rodrigues; Macedo,Felipe Barros. |
| A escória siderúrgica é uma alternativa para a correção da acidez dos solos e é constituída de silicato de cálcio. Neste estudo, avaliaram-se os efeitos residuais da aplicação de silicato de cálcio nos atributos químicos do solo e da planta em Latossolo Vermelho distroférrico típico com capim-Marandu (Brachiaria brizantha cv. Marandu), sob intensidades de pastejo em lotação rotacionada. O delineamento experimental foi de blocos ao acaso, com intensidades de pastejo avaliadas pelas ofertas diárias de forragem de 50, 100, 150 e 200 kg t-1 de MS por PV nas parcelas experimentais, enquanto a aplicação superficial de silicato de cálcio combinado com calcário dolomítico, respectivamente, nas doses 0 + 0; 2 + 0; 4 + 0; 6 + 0; 2 + 4; 4 + 2 e 0 + 6 t ha- 1 nas... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Forragem; Silicato de cálcio; Silício. |
| Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832008000300029 |
| |
|
|
| Luz,Pedro Henrique de Cerqueira; Herling,Valdo Rodrigues; Braga,Gustavo José; Vitti,Godofredo César; Lima,César Gonçalves de. |
| Numa pastagem degradada de capim-Tobiatã (Panicum maximum Jacq cv. Tobiatã), em Pirassununga - SP, instalou-se um experimento para verificar os efeitos de doses e tipos de calcário com ou sem incorporação, sobre o perfilhamento, a cobertura vegetal e a produtividade da pastagem durante seis cortes no período de 1996 a 1997. A produção de matéria seca não respondeu a tipos e doses de calcário, no entanto, a prática da incorporação com grade mostrou-se efetiva e, no tocante aos cortes, houve acréscimo de produção no verão e redução no inverno. A cobertura vegetal apresentou 72,8% de ocupação para planta forrageira e indicou tendência de menores áreas de solo descoberto nos tratamentos com calcário calcinado. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Calagem; Cobertura vegetal; Matéria seca; Meristema apical; Perfilhamento. |
| Ano: 2000 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982000000400004 |
| |
|
|
| Luz,Pedro Henrique de Cerqueira; Faria,Letícia de Abreu; Macedo,Felipe Barros de; Herling,Valdo Rodrigues; Sanches,Antonio Batista; Rodrigues,Rosane Cláudia. |
| Application of calcium silicate (SiCa) as soil acidity corrective was evaluated in a Rhodic Hapludox soil with palisade grass conducted under pasture rotation system with different grazing intensities. Experimental design was complete randomized blocks with four grazing intensities - grazing intensities were imposed by forage supply (50, 100, 150 and 200 kg t-1 of DM per LW) - in experimental plots with four replicates and, in the subplots, with seven doses of calcium silicate combined with lime: 0+0, 2+0, 4+0, 6+0, 2+4, 4+2 and 0+6 t ha-1, respectively. In the soil, it was evaluated the effect of four levels of calcium silicate (0, 2, 4 and 6 t ha-1) at 45, 90, and 365 days at three depths (0-10, 10-20 and 20-40 cm) and at 365 days, it was included one... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Calcium silicate; Forage; Limestone; Silicon. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982011000700009 |
| |
|
|
| Braga,Gustavo José; Pedreira,Carlos Guilherme Silveira; Herling,Valdo Rodrigues; Luz,Pedro Henrique de Cerqueira. |
| O objetivo deste trabalho foi avaliar a eficiência de pastejo, o desaparecimento de forragem e a variabilidade espacial do dossel em pastagens de capim-marandu sob diferentes ofertas de forragem em pastejo realizado com bovinos da raça Nelore, em Pirassununga, SP. O delineamento foi em blocos completos ao acaso e os tratamentos consistiram de 5, 10, 15 e 20 kg de massa de forragem por 100 kg de peso vivo (PV) por dia (%), aplicados em lotação rotativa. A taxa de desaparecimento de forragem respondeu positivamente ao aumento da oferta de forragem, oscilando de 2,3 a 6,5 kg de forragem por 100 kg de PV por dia em 2003 e de 2,3 a 6,2 kg por 100 kg de PV por dia em 2004. O desaparecimento de forragem por área não diferiu em 2003 (média = 56 kg ha-1 por dia),... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Brachiaria brizantha; Desaparecimento de forragem; Lotação rotativa; Perdas de forragem; Acúmulo de forragem; Variabilidade espacial. |
| Ano: 2007 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2007001100017 |
| |
|
|
| Faria,Letícia de Abreu; Nascimento,Carlos Antonio Costa do; Ventura,Barbara Paquier; Florim,Gabriela Perissinotto; Luz,Pedro Henrique de Cerqueira; Vitti,Godofredo Cesar. |
| Hygroscopic fertilizers tend to absorb moisture from the air and may have undesirable characteristics such as moistness, clumping and lower fluidity, hampering the application. The increasing use of urea is due to its numerous advantages, although this nitrogen (N) source is highly susceptible to volatilization losses, particularly when applied to the soil surface of management systems with conservation of crop residues. The volatilization losses can be minimized by slow or controlled-release fertilizers, with controlled water solubility of the urea-coating materials; and by stabilized fertilizers, which prolong the period during which N remains in the amide or ammonia forms by urease inhibitors. This study evaluated the hygroscopicity of and ammonia... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Boric acid; Sulfur; Crop residues; Copper sulphate. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832014000300026 |
| |
|
|
| Faria,Letícia de Abreu; Nascimento,Carlos Antonio Costa do; Vitti,Godofredo Cesar; Luz,Pedro Henrique de Cerqueira; Guedes,Elaine Maria Silva. |
| In Brazilian agriculture, urea is the most commonly used nitrogen (N) source, in spite of having the disadvantage of losing considerable amounts of N by ammonia-N volatilization. The objectives of this study were to evaluate: N lossby ammonia volatilization from: [urea coated with copper sulfate and boric acid], [urea coated with zeolite], [urea+ammonium sulfate], [urea coated with copper sulfate and boric acid+ammonium sulfate], [common urea] and [ammonium nitrate]; and the effect of these N source son the maize yield in terms of amount and quality. The treatments were applied to the surface of a soil under no-tillage maize, in two growing seasons. The first season (2009/2010) was after a maize crop (maize straw left on the soil surface) and the second... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Boric acid; Copper sulfate; Coated urea; Volatilization; Zeolite. |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832013000400014 |
| |
|
| |
|
|
| Pereira,Lilian Elgalise Techio; Passos,Bruna Scalia de Araújo; Herling,Valdo Rodrigues; Luz,Pedro Henrique de Cerqueira; Avanzi,Junior Cesar. |
| ABSTRACT Changes in morphological composition and in the plant population were evaluated during late spring, summer and autumn, in swards of Brachiaria decumbens cv. Basilisk in response to liming (C0.0, without liming; C0.7, limestone amount equivalent to 0.7 ton ha-1; and C1.0, limestone amount equivalent to 1.0 ton ha-1), which were subjected to severe or lenient cutting (40 or 60% of the pre-cutting height, respectively). Increased limestone doses did not result in higher herbage mass (HM), leaf area index (LAI) or proportion of leaves (%L) in the pre-harvest. However, lower proportion of dead material was registered in C0.7 treatment. The treatments C0.0 e C0.7 had higher %L during late spring and summer when associated to severe cutting regimes... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Soil acidity; Canopy height; Management strategies. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-66902018000400673 |
| |
|
|
| Alves,Ana Carolina; Oliveira,Patrícia Perondi Anchão; Herling,Valdo Rodrigues; Trivelin,Paulo Cesar Ocheuze; Luz,Pedro Henrique de Cerqueira; Alves,Teresa Cristina; Rochetti,Ramon Cellin; Barioni Júnior,Waldomiro. |
| Gaseous N losses from soil are considerable, resulting mostly from ammonia volatilization linked to agricultural activities such as pasture fertilization. The use of simple and accessible measurement methods of such losses is fundamental in the evaluation of the N cycle in agricultural systems. The purpose of this study was to evaluate quantification methods of NH3 volatilization from fertilized surface soil with urea, with minimal influence on the volatilization processes. The greenhouse experiment was arranged in a completely randomized design with 13 treatments and five replications, with the following treatments: (1) Polyurethane foam (density 20 kg m-3) with phosphoric acid solution absorber (foam absorber), installed 1, 5, 10 and 20 cm above the soil... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Fertilizer-N; Ammonia absorber; 15N; NH3-N loss. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832011000100012 |
| |
|
|
| Rodrigues,Rosane Cláudia; Mourão,Gerson Barreto; Brennecke,Kathery; Luz,Pedro Henrique de Cerqueira; Herling,Valdo Rodrigues. |
| Objetivou-se avaliar a produção de massa seca das folhas, a relação folha/colmo e alguns índices de crescimento do capim-xaraés submetido a doses de nitrogênio (N) e potássio (K). O experimento foi conduzido em casa-de-vegetação no período de novembro/2004 a fevereiro/2005. Adotou-se esquema fatorial 4 <FONT FACE=Symbol>´</FONT> 3, perfazendo 12 combinações, as quais foram distribuídas em delineamento experimental inteiramente casualizado, com quatro repetições, perfazendo um total 48 unidades experimentais. Foram utilizadas quatro doses de N (0, 75, 150 e 225 mg dm-3) e três doses de K (0, 50 e 100 mg dm-3). Verificou-se efeito das doses de N na produção de massa seca das folhas e na produção de massa seca total, em todos os cortes, com maior... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Área foliar específica; Nutrição mineral; Razão de área foliar; Razão de peso foliar. |
| Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982008000300003 |
| |
|
|
| Braga,Gustavo José; Pedreira,Carlos Guilherme Silveira; Herling,Valdo Rodrigues; Luz,Pedro Henrique de Cerqueira; Marchesin,Wilson Aparecido; Macedo,Felipe Barros. |
| Indirect, non-destructive methods for estimating herbage mass on pasture may help growers to better estimate herbage mass and manage the grazing process. The objective of this study was to evaluate two methods for estimating herbage mass on Marandu palisadegrass [Brachiaria brizantha (A. Rich.) Stapf] pastures, over two grazing seasons. The relationships between herbage mass and two indirect, non-destructive measurements (sward surface height - SSH and rising plate meter - RP) were analyzed via regression analysis. Mean determination coefficients (r²) for the regression models were 0.82 and 0.91 for RP and SSH, respectively. Time within season influenced both slope (b) and intercept (a) of the regression models in both methods. The change in model... |
| Tipo: Info:eu-repo/semantics/report |
Palavras-chave: Brachiaria brizantha; Sward surface height; Herbage allowance; Rising plate meter; Linear regression. |
| Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162009000100018 |
| |
|
|
| Romualdo,Liliane Maria; Luz,Pedro Henrique de Cerqueira; Baesso,Murilo Mesquita; Devechio,Fernanda de Fatima da Silva; Bet,Jessica Angela. |
| ABSTRACT Image analysis can provide information extracted from the leaves of crops, and contribute to early identification of nutrient deficiency. The objective of this study was to recognize nutritional nitrogen (N) patterns in maize plants, at the V4 and V7 stages, using digital image analysis based on spectral indexes. The experiment was carried out in a greenhouse under hydroponic cultivation. Treatments consisted of a completely randomized design, in a 4 × 2 factorial arrangement, with four replications. The factors were constituted by the doses of N (0; 3.0; 6.0 e 15 mmol L-1) combined at V4 and V7. In each stage, digital images were taken of leaf blades, with subsequent chemical composition and image analysis. For image recognition and... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Zea mays L.; Image analysis; Mineral nutrition; Image processing.. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-66902018000200183 |
| |
|
|
| Braga,Gustavo José; Pedreira,Carlos Guilherme Silveira; Herling,Valdo Rodrigues; Luz,Pedro Henrique de Cerqueira; Lima,César Gonçalves de. |
| In ruminant-forage systems herbage allowance (HAL) has a major impact on grazing intensity and sward structure, affecting animals, plants, and ultimately, pasture yield. Data on HAL responses of tropical cultivated pastures are scarce and this information may be useful in optimizing pasture utilization. The objective of this study was to describe and contrast sward structure and herbage accumulation responses of 'Marandu' palisadegrass [Brachiaria brizantha (A.Rich.) Stapf] pastures to HAL during two grazing seasons (warm-rainy season of 2003 and 2004). Treatments were four daily HAL levels, 5, 10, 15 and 20 kg herbage mass per 100 kg live weight (%) in a rotational stocking system with 35 days of grazing cycle (28-day rest; 7-d grazing). Post-graze swards... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Herbage accumulation; Sward height; Light interception; Forage mass. |
| Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162006000200003 |
| |
|
|
| Luz,Pedro Henrique de Cerqueira; Herling,Valdo Rodrigues; Braga,Gustavo José; Vitti,Godofredo César; Lima,César Gonçalves de. |
| As características agronômicas da pastagem dependem da qualidade do solo. Neste trabalho foram avaliados os efeitos de tipos e doses de calcário, com e sem incorporação, em algumas características agronômicas de uma pastagem degradada de Panicum maximum Jacq. cv. Tobiatã, num Latossolo Vermelho distrófico. As avaliações ocorreram durante quatro cortes consecutivos no período das chuvas ("verão") de 1995/96 e um corte no período seco ("inverno") em 1996. A produção de matéria seca do capim-Tobiatã aumentou com o método de incorporação com grade, devido ao efeito mecânico, porém não respondeu aos tipos e doses de calcário, sendo observadas as maiores produções no 4º corte ("verão"). Foram observados aumentos na cobertura de solo pela planta forrageira para... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Composição botânica; Pastagem degradada; Perfilhamento; Meristema apical. |
| Ano: 2002 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162002000100022 |
| |
|
|
| Altarugio,Lucas Miguel; Loman,Marcos Harm; Nirschl,Matheus Gomes; Silvano,Rafael Gil; Zavaschi,Eduardo; Carneiro,Leandro de Mello e Silva; Vitti,Godofredo Cesar; Luz,Pedro Henrique de Cerqueira; Otto,Rafael. |
| Abstract: The objective of this work was to evaluate the effect of magnesium foliar spray on yield performance of soybean (Glycine max) and corn (Zea mays) cultivated in soil with adequate levels of base saturation and magnesium content in Brazil. The field trials were conducted on a Typic Hapludox cultivated with soybean and corn in the 2013/2014 and 2014/2015 crop seasons, respectively. Treatments consisted of Mg rates (50, 100, 250, 500, 1,000 and 1,500 g ha-1 and a control without Mg) applied during the V4, R1, and R5.1 (soybean) or V4 and R2 (corn) phenological growth stages as magnesium sulfate heptahydrate (MgSO4∙7H2O). The SPAD index, leaf Mg content, grain yield, and 100-grain weight were evaluated. The Mg foliar spray increased the SPAD index in... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Glycine max; Zea mays; Foliar fertilization; Magnesium sulfate. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2017001201185 |
| |
| Registros recuperados: 16 | |
|
|
|
