In-furrow inoculation with Bradyrhizobium alternatively to seed inoculation of soybean
01/Dec/2010
Biological N fixation in soybean is indispensable in Brazil, sparing the use of mineral N and reducing crop production costs. The objective of this study was to compare in-furrow inoculation of soybean with Bradyrhizobium to the traditional practice of seed inoculation, in an experiment performed in a soil with low organic matter content and without soybean-nodulating rhizobia. A field experiment was carried out in the Cerrado of Roraima in 2006 and repeated in 2007, with the treatments: (1) control (no […]
Microbial and enzymatic activity in soil after organic composting
01/Jun/2010
Microbial activity and biochemical properties are important indicators of the impact of organic composting on soil. The objective of this study was to evaluate some indicators of soil microbial and biochemical processes after application of compost (household waste). A Typic Acrustox, sampled at a depth of 10 cm under Cerrado biome vegetation, was evaluated in three treatments: control (soil without organic compost amendment) and soil with two doses of domestic organic compost (10 and 20 g kg-1 soil). The following properties were evaluated: […]
Gypsum in management systems and soybean productivity in southwest region of Goiás
01/Apr/2010
The tilling of areas in no-tillage to several years and the use of gypsum practices are observed among the farmers in southwestern Goiás. This study was carried out to evaluate the effect of gypsum rates (0, 1, 2, 4 e 6 Mg ha-1) on some chemical attributes in the soil’s depth and in soybean yield in area under long-term no-till, with and without tillage. A complete randomized block scheme with a split-split-plot design with four replicates was used. The area […]
Influence of fungicide seed treatment on soybean nodulation and grain yield
01/Aug/2009
Biological N2 fixation is a major factor contributing to the increased competitiveness of Brazilian soybeans on the international market. However, the contribution of this process may be limited by adverse conditions to symbiotic bacteria, such as fungicide seed treatments. This study aimed to evaluate the effects of the fungicides carbendazim + thiram and carboxin + thiram on soybean nodulation, plant growth and grain yield. Two field experiments were carried out in the Cerrado region of the State of Roraima, in […]
Respiratory activity of soil microbiota and glucose content in response to phosphorus addition in Cerrado soil- Brazil
01/Oct/2008
Metabolic activity of microorganisms is one of the main processes of control on the nutrient transformation in soil. However, the activity of the soil microbiota is affected by various factors such as the available nutrients, including phosphorus. The present work had as objective to show an approach of the effect of phosphorus addition (50 to 500 mg kg-1 P of dry soil) on the respiratory response of soil microbiota and the amount of extra and intracellular glucose in typic acrustox of Cerrado.The […]
Phosphorus fractions in soil cultivated with corn as affected by different phosphates and application methods
01/Apr/2008
The land use history and management of fertilization influence the soil phosphorus supply capacity. In this study, the P fractions in a Red Argisol (Ultissol) of the cerrado region were evaluated under different application methods and with phosphorus sources of different solubility, after three successive corn crops. The area had already been fertilized and cultivated in the past and remained covered with Brachiaria grass. A randomized block design with four replications was used, in a 4 x 3 + 1 factorial scheme, involving four […]
Spatial soil fertility variability in a homogeneously managed corn field
01/Oct/2006
Insights on the variability of soil fertility in cultivated areas can contribute significantly to a rationalized use of fertilizers and soil amendments. The objective of this study was to determine the soil fertility variability through the fractionation of a commercial corn field into small management cells. The study was carried out on the farm Alto Alegre, Planaltina, GO, Brazil, on an Oxisol previously under Cerrado (savannah) in an area of 373 ha under corn in the 2003/2004 growing season. A polygon […]
Soil water dynamics in a toposequence under Savanna Woodland (Cerradão) in Assis, SP, Brazil
01/Jun/2006
The aim of this study was to characterize the morphological, physical and hydraulic soil properties in a toposequence under native plant cover in a permanent observation plot of 320 x 320 m installed in the Assis Ecological Station, São Paulo State, Brazil. The plot is covered by a remnant Savanna Woodland (Cerradão) vegetation of the southern border zone of the great Cerrado domain. The bi-dimensional geometry (horizontal and vertical) of the soil horizons in a toposequence provided details on the […]
Microbial biomass and enzyme activities in soils under native vegetation and under annual and perennial cropping systems at the Primavera do Leste region – Mato Grosso state
01/Jun/2003
Primavera do Leste is one of the most important farming areas of Mato Grosso State. This study was carried out in a Red-Yellow Latosol to evaluate the microbial biomass and enzyme activities in soils under native vegetation (known as “Cerradão”) and in soils under annual and perennial cropping systems. Soil samples were collected, at the beginning of the rainy season, at two depths (0-5 and 5-20 cm) in areas under a vineyard (row and between rows), annual crops (soybean) and native […]
Land evaluation combined with climatic risk estimate for corn using geographic information system
01/Sep/2002
The objective of this work was to propose a methodology for land evaluation based on planting information, soil data extracted from a soil survey in a scale 1:50,000, and estimate of climatic risk, using a geographic information system (GIS). The reference area was the Jardim watershed, in the Federal District (Brazil). A water balance model was used to simulate the climatic risk for the corn crop (Zea mays L.), at nine different planting dates. Quantitative values for corn productivity parameters […]