3290 results

Soil organic matter in highland Leptosols: influence of pasture management on composition and content

Mariana da Luz Potes, Deborah Pinheiro Dick, Ricardo Simão Diniz Dalmolin, Heike Knicker, Alessandro Samuel da Rosa

01/Feb/2010

Burning pastures after the winter is a traditional practice in highland soils, whose main purpose is the regrowth of vegetation. However, the impact of fire, as well as the influence of grazing on the organic matter of Leptosols is still unknown. The purpose of this study was to investigate the composition and content of organic matter in soil profiles from São José dos Ausentes, state of Rio Grande do Sul, and to relate the results with the occurrence of burning […]

Physical properties of a humic cambisol under tillage and cropping systems after twelve years

Andréia Patrícia Andrade, Álvaro Luiz Mafra, Gizele Rejane Baldo, Cristiano Dela Piccolla, Ildegardis Bertol, Jackson Adriano Albuquerque

01/Feb/2010

Soil is the basis underlying the food production chain and it is fundamental to improve and conserve its productive capacity. Imbalanced exploitation can degrade agricultural areas physical, chemical and biologically. The objective of this study was to evaluate some soil physical properties and their relation with organic carbon contents of a Humic Dystrudept under conventional tillage (CT) and no-tillage (NT), for 12 years in rotation (r) and succession (s) cropping systems. The experiment was carried out in Lages, SC (latitude […]

Erosivity and hydrological characteristics of rainfalls in Rio Grande (RS, Brazil)

Marcos Gabriel Peñalva Bazzano, Flávio Luiz Foletto Eltz, Elemar Antonino Cassol

01/Feb/2010

Specific rainfall characteristics vary among regions and their erosion potential must be known for the planning of agricultural and civil engineering activities. For Rio Grande (RS, Brazil), the erosivity and relationships with the precipitation and rainfall coefficient, rainfall hydrologic patterns and return period were determined based on rainfall data of 23 years. For each erosive rainfall the segments of the rainfall chart with the same intensity were separated together and the data registered in worksheets. The mean monthly and annual […]

Flooded rice yield as affected by levels of water salinity in different stages of its cycle

Thiago Isquierdo Fraga, Felipe de Campos Carmona, Ibanor Anghinoni, Silvio Aymone Genro Junior, Elio Marcolin

01/Feb/2010

Losses of productivity of flooded rice in the State of Rio Grande do Sul, Brazil, may occur in the Coastal Plains and in the Southern region due to the use of saline water from coastal rivers, ponds and the Laguna dos Patos lagoon, and the sensibility of the plants are variable according to its stage of development. The purpose of this research was to evaluate the production of rice grains and its components, spikelet sterility and the phenological development of […]

Leaf area of common bean genotypes during early pod filling as related to plant adaptation to limited phosphorus supply

Roberto Santos Trindade, Adelson Paulo Araújo, Marcelo Grandi Teixeira

01/Feb/2010

Low phosphorus supply markedly limits leaf growth and genotypes able to maintain adequate leaf area at low P could adapt better to limited-P conditions. This work aimed to investigate the relationship between leaf area production of common bean (Phaseolus vulgaris) genotypes during early pod filling and plant adaptation to limited P supply. Twenty-four genotypes, comprised of the four growth habits in the species and two weedy accessions, were grown at two P level applied to the soil (20 and 80 […]

Development of dris and CND norms and evaluation of nutritional status of cotton

Ademar Pereira Serra, Marlene Estevão Marchetti, Antonio Carlos Tadeu Vitorino, José Oscar Novelino, Marcos Antonio Camacho

01/Feb/2010

Among the different methods of assessing the nutritional status of plants, DRIS and CND have the main purpose of ranking the limiting nutrients. This study aimed to develop DRIS and CND norms and compare the diagnoses of these methods in evaluations of cotton cash crops in the region of São Desidério, state of Bahia, Brazil. The database consisted of the total nutrient content of 65 whole leaf samples and seed cotton yield of plots with an average size of 120 […]

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 […]

Spatial and temporal variability of crop yield and some Rhodic Hapludox properties under no-tillage

Osvaldo Guedes Filho, Sidney Rosa Vieira, Márcio Koiti Chiba, César Hideo Nagumo, Sônia Carmela Falci Dechen

01/Feb/2010

Soil properties are closely related with crop production and spite of the measures implemented, spatial variation has been repeatedly observed and described. Identifying and describing spatial variations of soil properties and their effects on crop yield can be a powerful decision-making tool in specific land management systems. The objective of this research was to characterize the spatial and temporal variations in crop yield and chemical and physical properties of a Rhodic Hapludox soil under no-tillage. The studied area of 3.42 […]

Influence of cattle manure and limestone on residual effects of phosphorus fertilizer in Brachiaria brizantha grown after common bean

Renato Ferreira de Souza, Valdemar Faquin, Rodrigo Reis Lima Sobrinho, Eliezer Augusto Baeta de Oliveira

01/Feb/2010

Phosphorus (P) deficiency is one of the most widespread limitations to the establishment and maintenance of pastures in tropical areas. This deficiency is mainly due to the low soil P content and adsorption/precipitation processes. The purpose of this study was to evaluate the influence of manure and lime applications on the residual effect of phosphorus applied to common bean on phosphorus nutrition and yield of Brachiaria brizantha grown in succession. Four experiments were conducted in a greenhouse, in a completely […]

Alterations in potassium, calcium and magnesium concentrations in marandu palisadegrass fertilized with nitrogen and sulfur rates

Karina Batista, Francisco Antonio Monteiro

01/Feb/2010

Alterations in Potassium, Calcium and Magnesium Concentrations in Marandu Palisadegrass Fertilized with Nitrogen and Sulfur Rates An efficient pasture use in intensive production systems depends on the balanced mineral nutrition of the forage plant. Our objective was to evaluate changes in potassium, calcium and magnesium concentrations of Brachiaria brizantha, cv. Marandu grown on an Entisol with nitrogen and sulfur rates. The experiment was carried out in a greenhouse, in Piracicaba, State of São Paulo, from December 2004 to April 2005. […]

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