NUTRIENT RELEASE FROM FORAGE STRAW INTERCROPPED WITH MAIZE AND FOLLOWED BY SOYBEAN
01/Jan/2015
In tropical regions there is rapid decomposition of plant material deposited on the soil, and the ability to recycle nutrients through this decomposition is one of the most important aspects of cover crops. The aim of this study was to evaluate the yield and nutrient release from forage crops intercropped with maize for silage, and soybean in succession. The study was conducted in the experimental area of Universidade Estadual Paulista, Ilha Solteira campus, Brazil. The experiment consisted of maize for […]
MYCORRHIZAL INOCULUM POTENTIAL AND THE IMPORTANCE OF THE MYCELIUM LENGTH FOR AGGREGATION OF RIPARIAN SOILS
01/Jan/2015
Arbuscular mycorrhizal fungi (AMF) play an important role in natural ecosystems as they influence plant nutrition and soil structure. The aim of this study was to determine the mycorrhizal inoculum potential and the relationship between mycorrhizal mycelium length of AMF and aggregation of riparian soils. Soil samples were collected in riparian areas in the Itajai Açu river watershed, between the municipalities of Gaspar and Navegantes, Santa Catarina, Brazil. Eight areas were sampled within three soil classes: Cambissolo (Inceptisol) (C), Gleissolo […]
USE OF IMAGE ANALYSIS TO DETERMINE THE SHAPE AND TEXTURE OF SANDS
01/Jan/2015
The Shape of sand grains plays an important role in evaluation of soil particle size distribution. However, in most sieving techniques it is assumed that grains are spherical and can be described by a single parameter, diameter. Moreover, the subjectivity of the tests used to estimate sand roughness makes it difficult to obtain data that accurately represent reality. The aim of this paper was to study the use of image analysis together with the degree of sphericity and fractal theory […]
PHOSPHORUS FERTILIZATION AND SOIL COMPACTION: SOYBEAN AND MAIZE ROOT SYSTEM AND SOIL PHYSICAL PROPERTIES
01/Jan/2015
Associated with the benefits of the no-till system for the soil, there may be the formation of a vertical gradient of fertility and a compacted layer caused by heavy farm machine traffic, which may modify the root growth of crops. The aim of this study was to evaluate the effect of rates and forms of phosphate fertilizer application and soil compaction by machine traffic on the physical properties and root system of soybeans and maize. The study was conducted in […]
ORGANIC PHOSPHORUS FRACTIONS IN SOIL FERTILIZED WITH CATTLE MANURE
01/Jan/2015
Inorganic phosphorus (Pi) usually controls the P availability in tropical soils, but the contribution of organic P (Po) should not be neglected, mainly in systems with low P input or management systems that promote organic matter accumulation. The aims of this study were to evaluate the changes in the Po fractions over time in soil fertilized and not fertilized with cattle manure and to correlate Po forms with available P extracted by anion exchange resin. The experiment was carried out […]
SPATIAL CORRELATION BETWEEN PHYSICAL PROPERTIES OF SOIL AND WEEDS IN TWO MANAGEMENT SYSTEMS
01/Jan/2015
The spatial correlation between soil properties and weeds is relevant in agronomic and environmental terms. The analysis of this correlation is crucial for the interpretation of its meaning, for influencing factors such as dispersal mechanisms, seed production and survival, and the range of influence of soil management techniques. This study aimed to evaluate the spatial correlation between the physical properties of soil and weeds in no-tillage (NT) and conventional tillage (CT) systems. The following physical properties of soil and weeds […]
YIELD OF THE IRRIGATED WHEAT CROP SUBJECTED TO NITROGEN APPLICATION AND TO INOCULATION WITH AZOSPIRILLUM BRASILENSE
01/Jan/2015
Inoculating wheat seeds with nitrogen-fixing bacteria such as Azospirillum brasilense may be beneficial to the crop and reduce the need for N application. Nevertheless, few studies have measured the benefit of this practice on irrigated wheat with the expectation of high yield and demand for N. The objective of this study was to evaluate the yield and N content of irrigated wheat under different N application rates, with and without inoculation with A. brasilense. Two experiments were carried out in […]
Reduction of green stem and leaf retention in soybean through greater nitrogen availability from seed treatment
01/Oct/2014
Problems related to leaf retention and lack of uniformity in maturation in the soybean crop have been reported in various regions of Brazil, including the State of Parana, presenting a challenge to Brazilian researchers. Several hypotheses for this problem have been raised in regard to plants nutritional imbalance and intensification of the problem, but no definitive conclusion has been reached. A field experiment was carried out at the Copacol Experimental Farm in Cafelandia, PR, to evaluate how nitrogen availability via […]
Effect of potassium sources and rates on arabica coffee yield, nutrition, and macronutrient export
01/Oct/2014
The use of potassium (K) rock powder can be an alternative for K supply of crops. Thus, to reduce K fertilizer imports from abroad, possibilities of extracting this nutrient from Brazilian rocks are being studied. The objective was to evaluate the effect of phonolite rock powder (F2) as K source (Ekosil®) on the air-dried fruit yield, nutrition and macronutrient export of Arabica coffee. The experiment was carried out on a dystroferric Red Latosol (Typic Haplorthox), in Piraju, São Paulo State, […]
Effects of pig slurry application on soil physical and chemical properties and glyphosate mobility
01/Oct/2014
Pig slurry applied to soil at different rates may affect soil properties and the mobility of chemical compounds within the soil. The purpose of this study was to evaluate the effects of rates of pig slurry application in agricultural areas on soil physical and chemical properties and on the mobility of glyphosate through the soil profile. The study was carried out in the 12th year of an experiment with pig slurry applied at rates of 0 (control), 50, 100 and […]
