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19 results

Potassium Fertilization for Long Term No-Till Crop Rotation in the Central-Southern Region of Paraná, Brazil

Renan Costa Beber Vieira, Sandra Mara Vieira Fontoura, Cimélio Bayer, Renato Paulo de Moraes, Eduardo Carniel

13/Sep/2016

ABSTRACT Fertilization programs for annual crops in the state of Paraná, southern Brazil, are based on studies that focused on conventional tillage and were established more than 30 years ago. The primary purpose of this study was to assess potassium (K) fertilization on long-term (>30 years) no-tillage soybean, corn, wheat, and barley crops grown in rotation on Oxisols in the central-southern region of Paraná. A total of 47 experiments were carried out from 2008 to 2013, three of which addressed […]

Substitution of Clay Content for P-Remaining as an Index of the Phosphorus Buffering Capacity for Soils of Rio Grande do Sul

Douglas Antonio Rogeri, Clesio Gianello, Leandro Bortolon, Magno Batista Amorim

23/Aug/2016

ABSTRACT Mehlich-1 soil extract is currently used in Rio Grande do Sul (RS) and Santa Catarina (SC) States, in Brazil, to evaluate soil phosphorus available to plants and Mehlich-1 is sensitive to soil buffering capacity. This limitation is overcome partly by soil separation into buffering classes based on soil clay content. However, soil clay content has some technical and operational limitations, such as the underestimation of soil clay levels in soils under no-till. The aim of this study was to […]

Methods to Quantify Nickel in Soils and Plant Tissues

Bruna Wurr Rodak, Milton Ferreira de Moraes, João Augusto Lopes Pascoalino, Adilson de Oliveira, Cesar de Castro, Volnei Pauletti

01/May/2015

In comparison with other micronutrients, the levels of nickel (Ni) available in soils and plant tissues are very low, making quantification very difficult. The objective of this paper is to present optimized determination methods of Ni availability in soils by extractants and total content in plant tissues for routine commercial laboratory analyses. Samples of natural and agricultural soils were processed and analyzed by Mehlich-1 extraction and by DTPA. To quantify Ni in the plant tissues, samples were digested with nitric […]

Phosphorus Fertilization for High Yield of Soybean, Maize, and Winter Cereal Crops in Rotation in Oxisols under Long-Term no-Till in the South Central Region of Parana, Brazil

Renan Costa Beber Vieira, Sandra Mara Vieira Fontoura, Cimélio Bayer, Renato Paulo de Moraes, Eduardo Carniel

01/May/2015

Although the State of Parana, Brazil, has adopted crop rotation and no-till (NT) systems, fertilizer application is still based on recommendations developed more than 30 years ago for monocropping under conventional tillage because fertilizer recommendations developed specifically for crop rotation under NT are lacking. The objective of our study was to consolidate P calibration and evaluate crop responses to P fertilization so as to propose a system of technical recommendations for P fertilization for soybean, maize, wheat, and barley grown […]

Chemical changes and evaluation of available P near the granules of triple superphosphate and diammonium phosphate in acid soils

Jaqueline Pereira Machado de Oliveira, Paulo Roberto Ernani, Luciano Colpo Gatiboni, Angélica Pegoraro

01/Oct/2014

Phosphorus has low mobility in the soil. Thus, its concentration near the granules of phosphate fertilizers in the soil is very high, which may affect P availability and the soil chemical composition in these regions. This study was carried out to evaluate the soil chemical composition near the granules of calcium or ammonium phosphates and P mobility in two Brazilian acid soils. The experiment was carried out in 2009 and treatments consisted of a combination of triple superphosphate (TSP) or […]

Zinc availabity for eucalypt seedlings in Cerrado soils

Fernando Antonio Vieira Rodrigues, Nairam Félix de Barros, Júlio César Lima Neves, Víctor Hugo Alvarez V, Roberto Ferreira Novais

01/Aug/2012

In Brazil, along with the expansion of clonal forestry, the management of more productive and more nutrient-demanding genotypes has led to the appearance of micronutrient deficiency symptoms, mainly of boron (B), and more recently, of copper (Cu) and of zinc (Zn), especially in Cerrado areas. The purpose of this study was to evaluate three extraction solutions to determine Zn availability (Mehlich-1, Mehlich-3 and DTPA pH 7.3) for eucalyptus seedlings grown in a greenhouse, on six Cerrado soil samples, and to […]

Comparison of conventional and alternative determination methods of soil sodium, potassium and phosphorus extracted with mehlich-1 solution

Ricardo Soares, Viviane Escaleira, David Vilas Boas de Campos, Maria Inês Couto Monteiro, Manuel Castro Carneiro, Ricardo Erthal Santelli, [...]

01/Feb/2012

The Na, K and P concentrations in soil extracts obtained by a conventional extraction method, at a soil:extractant (Mehlich-1) ratio of 1:10, were compared with those found at a soil:extractant (Mehlich-1) ratio of 1:5. Also, the data obtained by conventional quantification techniques, in which Na and K are quantified by flame photometry and P by UV-Vis molecular absorption spectrophotometry, were compared with those found by inductively coupled plasma optical emission spectrometry (ICP OES). Fifteen Brazilian soil samples were analyzed. In […]

Availability of a soluble phosphorus source applied to soil samples with different acidicity levels

Ricardo Almeida Viégas, Roberto Ferreira Novais, Fernanda Schulthais

01/Aug/2010

Considerations on the interactions of P in the soil-plant system have a long history, but are still topical and not yet satisfactorily understood. One concern is the effect of liming before or after application of soluble sources on the crop yield and efficiency of available P under these conditions. The aim of this study was to evaluate the effect of soil acidity on availability of P from a soluble source, based on plant growth and chemical extractants. Nine soil samples […]

Mobility of inorganic and organic phosphorus forms under different levels of phosphate and poultry litter fertilization in soils

Fabrício de Oliveira Gebrim, Roberto Ferreira Novais, Ivo Ribeiro da Silva, Fernanda Schulthais, Leonardus Vergütz, Lorena Costa Procópio, [...]

01/Aug/2010

The eutrophication of aquifers is strongly linked to the mobility of P in soils. Although P mobility was considered irrelevant in a more distant past, more recent studies have shown that P, both in organic (Po) and inorganic forms (Pi), can be lost by leaching and eluviation through the soil profile, particularly in less weathered and/or sandier soils with low P adsorption capacity. The purpose of this study was to determine losses of P forms by leaching and eluviation from […]

Simultaneous multielement extraction with the Mehlich-1 solution for Southern Brazilian soils determined by ICP-OES and the effects on the nutrients recommendations to crops

Leandro Bortolon, Clesio Gianello

01/Feb/2010

The amounts of macro (P, K, Ca and Mg) and micronutrients (Cu and Zn) extracted with the Mehlich-1 (M1) solution, by the 1.0 mol L-1 KCl (KCl) and with the 0.1 mol L-1 HCl (HCl) for representative soil types of the Rio Grande do Sul state (Brazil) were compared with those extracted with the Mehlich-1 solution determined with the inductively coupled plasma optical emission spectroscopy (ICP). The amounts of nutrients extracted by the different methods showed high correlation coefficients. On […]

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