401 results

WATER INFILTRATION IN TWO CULTIVATED SOILS IN SOUTHERN BRAZIL

Ildegardis Bertol, Fabrício Tondello Barbosa, Camilo Bertol, Rodrigo Vieira Luciano

01/Mar/2015

Infiltration is the passage of water through the soil surface, influenced by the soil type and cultivation and by the soil roughness, surface cover and water content. Infiltration absorbs most of the rainwater and is therefore crucial for planning mechanical conservation practices to manage runoff. This study determined water infiltration in two soil types under different types of management and cultivation, with simulated rainfall of varying intensity and duration applied at different times, and to adjust the empirical model of […]

PHYTOAVAILABILITY OF COPPER IN INDUSTRIAL BY-PRODUCTS AND MINERAL FERTILIZERS

Camila Prado Cenciani de Souza, Cleide Aparecida de Abreu, José Francisco da Cunha, Geraldo Magela da Costa, Cristiano Alberto de Andrade

01/Mar/2015

Alternative copper (Cu) sources could be used in fertilizer production, although the bioavailability of copper in these materials is unknown. The objective of this study was to evaluate the extractants neutral ammonium citrate (NAC), 2 % citric acid, 1 % acetic acid, 10 % HCl, 10 % H2SO4, buffer solution pH 6.0, DTPA, EDTA, water, and hot water in the quantification of available Cu content in several sources, relating them to the relative agronomic efficiency (RAE) of wheat grown in […]

FERTILIZER RECOMMENDATION SYSTEM FOR MELON BASED ON NUTRITIONAL BALANCE

José Aridiano Lima de Deus, Ismail Soares, Júlio César Lima Neves, José Francismar de Medeiros, Fábio Rodrigues de Miranda

01/Mar/2015

Melon is one of the most demanding cucurbits regarding fertilization, requiring knowledge of soils, crop nutritional requirements, time of application, and nutrient use efficiency for proper fertilization. Developing support systems for decision-making for fertilization that considers these variables in nutrient requirement and supply is necessary. The objective of this study was parameterization of a fertilizer recommendation system for melon (Ferticalc-melon) based on nutritional balance. To estimate fertilizer recommendation, the system considers the requirement subsystem (REQ), which includes the demand for […]

SOIL STRUCTURE UNDER IRRIGATED BEANS AND DIFFERENT SOIL MANAGEMENT PRACTICES

Lorena Adriana de Gennaro, Zigomar Menezes de Souza, Laura Fernanda Simões da Silva, Miguel Cooper, Milton César Costa Campos

01/Mar/2015

Agricultural management affects soil structure, modifying soil physical properties and soil water movement. The objective of this study was to evaluate the effects of no-tillage (NT) and conventional tillage (CT) on soil structure through physical properties and pore distribution in 2-D digital images. The study was conducted in an Oxisol with a randomized block design. Soil bulk density, soil macroporosity, mean weighted diameter (MWD), saturated hydraulic conductivity (SHC), and analysis of 2-D digital images (156.25 μm2 resolution) were evaluated at […]

APPRAISAL OF THE SNAP MODEL FOR PREDICTING NITROGEN MINERALIZATION IN TROPICAL SOILS UNDER EUCALYPTUS

Philip James Smethurst, José Leonardo de Moraes Gonçalves, Ana Paula Pulito, Simone Gomes, Keryn Paul, Clayton Alcarde Alvares, [...]

01/Mar/2015

The Soil Nitrogen Availability Predictor (SNAP) model predicts daily and annual rates of net N mineralization (NNM) based on daily weather measurements, daily predictions of soil water and soil temperature, and on temperature and moisture modifiers obtained during aerobic incubation (basal rate). The model was based on in situ measurements of NNM in Australian soils under temperate climate. The purpose of this study was to assess this model for use in tropical soils under eucalyptus plantations in São Paulo State, […]

LEAST LIMITING WATER RANGE IN CONSTRUCTED SOIL AFTER COAL MINING IN DIFFERENT CRITICAL LIMITS OF PENETRATION RESISTANCE AND WATER CONTENT

Ezequiel Cesar Carvalho Miola, Eloy Antonio Pauletto, Cláudia Liane Rodrigues de Lima, Luiz Fernando Spinelli Pinto, Luis Carlos Timm

01/Mar/2015

In quantifying the least limiting water range (LLWR), different critical limits of resistance to penetration (RP) and moisture at field capacity (θFC) are generally used. For agricultural soils, these values are documented in the literature. However, for constructed soil after coal mining, there is a large information gap. The aim of this study was to quantify the least limiting water range of a constructed soil under different cover crops in a coal mining area in Candiota, RS (Southern Brazil), considering […]

NUTRIENT DEMAND BY THE CARROT CROP IS INFLUENCED BY THE CULTIVAR

Rosiane Filomena Batista Almeida Aquino, Natália Silva Assunção, Leonardo Angelo Aquino, Priscila Maria de Aquino, Guilherme Anthony de Oliveira, André Mundstock Xavier de Carvalho

01/Mar/2015

Farmers must carefully choose the cultivar to be grown for a successful carrot crop. The yield potential of the cultivar may influence nutrient demand and should be known to plan for fertilization application. The aim of this study was to evaluate the cultivar effect on carrot yield and on the nutrient content and quantities allocated to leaves and roots. Three experiments were set up in two crop seasons in Rio Paranaíba, MG, Brazil. In the first season, typical summer, 10 […]

SHOOT DRY MATTER AND SHOOT MACRONUTRIENT ACCUMULATION IN NIGER

Munir Mauad, Rodrigo Arroyo Garcia, Rosilda Mara Mussury Franco Silva, Thiago Alexandre Freire da Silva, Igor Miguel Schroeder, Carlos Henrique Knudsen, [...]

01/Mar/2015

Studying nutrient uptake and dry matter accumulation in plants as affected by crop developmental stages is essential to establish and assist strategies for crop fertilization. The aim of this study was to assess shoot dry matter and macronutrient accumulation in Guizotia abyssinica (niger) at different growth and development stages. A randomized block experimental design with five replications was used. Shoot samples of the plants were taken at 15, 30, 45, 60, 75, and 90 days after seedling emergence (DAE). At […]

STABILIZED NITROGEN SOURCES AS AN ALTERNATIVE FOR INCREASING GRAIN YIELD AND NITROGEN USE EFFICIENCY BY MAIZE

Murilo Renan Mota, Luis Sangoi, Diego Eduardo Schenatto, Willian Giordani, Cristian Majolo Boniatti, Leonardo Dall’Igna

01/Mar/2015

The use of stabilized N sources, with mechanisms for inhibition of urease enzyme and with ammonium nitrification inhibitors, may help to achieve higher grain yields, contributing to the sustainability of agricultural activity. The aim of this study was to evaluate the effect of different mineral N sources and application rates on maize grain yield and N use efficiency. A field experiment was carried out in Lages, SC, Brazil, in a randomized block design in split-plots. Nitrogen was side-dressed in the […]

HEAVY METALS AND MICRONUTRIENTS IN THE SOIL AND GRAPEVINE UNDER DIFFERENT IRRIGATION STRATEGIES

Vanessa de Souza Oliveira, Augusto Miguel Nascimento Lima, Alessandra Monteiro Salviano, Luís Henrique Bassoi, Giuliano Elias Pereira

01/Jan/2015

Soils under natural conditions have heavy metals in variable concentrations and there may be an increase in these elements as a result of the agricultural practices adopted. Transport of heavy metals in soil mainly occurs in forms dissolved in the soil solution or associated with solid particles, water being their main means of transport. In this context, the aim of this study was to evaluate the heavy metal and micronutrient content in the soil and in the grapevine plant and […]

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