3290 results

Least limiting water range in assessing compaction in a Brazilian Cerrado latosol growing sugarcane

Wainer Gomes Gonçalves, Eduardo da Costa Severiano, Fabiano Guimarães Silva, Kátia Aparecida de Pinho Costa, Wellingthon da Silva Guimarães-Junnyor, Gabriel Bressiani Melo

01/Apr/2014

In the south-central region of Brazil, there is a trend toward reducing the sugarcane inter-harvest period and increasing traffic of heavy harvesting machinery on soil with high water content, which may intensify the compaction process. In this study, we assessed the structural changes of a distroferric Red Latosol (Oxisol) by monitoring soil water content as a function of the Least Limiting Water Range (LLWR) and quantified its effects on the crop yield and industrial quality of the first ratoon crop […]

Structural quality of polyacrylamide-treated cohesive soils in the coastal tablelands of Pernambuco

Diego Vandeval Maranhão de Melo, Brivaldo Gomes de Almeida, Edivan Rodrigues de Souza, Laércio Santos Silva, Paulo Klinger Tito Jacomine

01/Apr/2014

Water-soluble polymers are characterized as effective flocculating agents due to their molecular features. Their application to soils with horizons with structural problems, e.g, a cohesive character, contributes to improvements in the physical quality and thus to the agricultural suitability of such soils. The purpose of this study was to evaluate the structural quality of soils with cohesive horizons of coastal tablelands in the State of Pernambuco treated with polyacrylamide (PAM) as chemical soil conditioner. To this end, three horizons (one […]

Production and quality of roses as affected by boron fertilization

Luiz Antônio Zanão Júnior, Maristela Pereira Carvalho-Zanão, Renildes Lúcio Ferreira Fontes, José Antônio Saraiva Grossi

01/Apr/2014

Many studies have shown the effects of boron (B) application on various crops; however, results on roses are scarce. The aim of this experiment was to evaluate the effects of B on the production and quality of roses (Rosa hybrida Shiny Terrazza®) under controlled conditions. Treatments consisted of five rates of B (0, 1, 4, 8 and 16 mg kg-1) applied in the substrate in a randomized block design with five replicates. We evaluated the cycle; number of flowers per […]

Fuzzy logic applied to the modeling of water dynamics in an Oxisol in northeastern Brazil

Antônio Cláudio Marques Afonso, André Maciel Netto, Wagner Estáquio de Vasconcelos

01/Apr/2014

Modeling of water movement in non-saturated soil usually requires a large number of parameters and variables, such as initial soil water content, saturated water content and saturated hydraulic conductivity, which can be assessed relatively easily. Dimensional flow of water in the soil is usually modeled by a nonlinear partial differential equation, known as the Richards equation. Since this equation cannot be solved analytically in certain cases, one way to approach its solution is by numerical algorithms. The success of numerical […]

Variability of soil fertility properties in areas planted to sugarcane in the State of Goias, Brazil

José Avelino Cardoso, Marilusa Pinto Coelho Lacerda, Thomaz Adolpho Rein, João de Deus Gomes dos Santos Junior, Cícero Célio de Figueiredo

01/Apr/2014

Soil sampling should provide an accurate representation of a given area so that recommendations for amendments of soil acidity, fertilization and soil conservation may be drafted to increase yield and improve the use of inputs. The aim of this study was to evaluate the variability of soil fertility properties of Oxisols in areas planted to sugarcane in the State of Goias, Brazil. Two areas of approximately 8,100 m2 each were selected, representing two fields of the Goiasa sugarcane mill in […]

Comparison of digestion methods to determine heavy metals in fertilizers

Ygor Jacques Agra Bezerra da Silva, Clístenes Williams Araújo do Nascimento, Caroline Miranda Biondi, Welka Preston

01/Apr/2014

The lack of a standard method to regulate heavy metal determination in Brazilian fertilizers and the subsequent use of several digestion methods have produced variations in the results, hampering interpretation. Thus, the aim of this study was to compare the effectiveness of three digestion methods for determination of metals such as Cd, Ni, Pb, and Cr in fertilizers. Samples of 45 fertilizers marketed in northeastern Brazil were used. A fertilizer sample with heavy metal contents certified by the US National […]

Partial substitution of soluble phosphate by rock phosphate in the planting of Eucalyptus benthamii and Eucalyptus dunnii in southern Brazil

Luciana Patrícia Rosa Dias, Luciano Colpo Gatiboni, Paulo Roberto Ernani, David José Miquelluti, Djalma Miler Chaves, Gustavo Brunetto

01/Apr/2014

Phosphorus fertilization is important for the initial growth of eucalyptus. Soluble phosphate (SP) sources are commonly used for this purpose because they offer fast dissolution in the soil, but these sources have higher costs than rock phosphate (RP), which has lower solubility. The aim of this study was to evaluate the use of RP as a partial substitute for SP for the initial supply of P to Eucalyptus benthamii and E. dunnii. Two field experiments were carried out (one with […]

Plant-available soil water capacity: estimation methods and implications

Bruno Montoani Silva, Érika Andressa da Silva, Geraldo César de Oliveira, Mozart Martins Ferreira, Milson Evaldo Serafim

01/Apr/2014

The plant-available water capacity of the soil is defined as the water content between field capacity and wilting point, and has wide practical application in planning the land use. In a representative profile of the Cerrado Oxisol, methods for estimating the wilting point were studied and compared, using a WP4-T psychrometer and Richards chamber for undisturbed and disturbed samples. In addition, the field capacity was estimated by the water content at 6, 10, 33 kPa and by the inflection point […]

Water erosion at three moments in the corn crop, affected by soil tillage and crop sowing methods

Leandro Bochi da Silva Volk, Neroli Pedro Cogo

01/Apr/2014

Apart from the soil tillage system, the soil surface conditions that govern the rainwater erosion process change during growth of the corn crop. At the same time, the physical conditions of the soil surface that govern soil losses are different from those that govern water losses by erosion. The hypothesis of this study is that these changes occurring during the growth of the corn crop reduce soil losses but do not reduce water losses by erosion. Based on that, this […]

Inoculation of sugarcane with diazotrophic bacteria

Nivaldo Schultz, Jeferson Alves da Silva, Jailson Silva Sousa, Rafael Cassador Monteiro, Renan Pedula Oliveira, Valfredo Almeida Chaves, [...]

01/Apr/2014

The sugarcane industry, a strategic crop in Brazil, requires technological improvements in production efficiency to increase the crop energy balance. Among the various currently studied alternatives, inoculation with diazotrophic bacteria proved to be a technology with great potential. In this context, the efficiency of a mixture of bacterial inoculant was evaluated with regard to the agronomic performance and N nutrition of sugarcane. The experiment was carried out on an experimental field of Embrapa Agrobiologia, in Seropédica, Rio de Janeiro, using […]

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