Common bean is one of the most important staples in Brazil. The objective of this study was to evaluate the common bean cv. Pérola yield and changes in soil chemical attributes as influenced by liming and manganese rates. The experiment was carried out in pots containing dystrophic Red Yellow Latosol (Oxisol). Treatments consisted of a 2 x 6 factorial combination of two limestone (CO3 and MgCO3 in a 3:1 molar ratio) rates, calculated to increase base saturation to 50 and […]

The application of sludges, especially sewage-sludge (SS) to agricultural soils is one of the most rational ways of using this residue. The purpose of this study was to investigate the effect of SS on some chemical properties of an SS-amended Ultisol under sugarcane (variety RB 855536) for two years; from October 2002 to August 2003 – growing season 2003/04 and from October 2003 to October 04, designated 2004/05 crop season. Eight treatments were evaluated: (a) control; (b) Mineral fertilization (120 kg ha-1 […]

Plant nutrient extraction has been used to remove inorganic ions from soil or other polluted media. In this study, the nutrient extraction capacity of the macrophytes Typha sp. and Eleocharis sp., cultivated as monoculture and as consortium, was evaluated in a growing medium containing rubble and leachate of an urban landfill. The plants were grown in wooden boxes containing rubble and leachate as substrate, in a plastic greenhouse, for five months. The total concentration and amount of macro (N, P, […]

The germination of Pisolithus spp. basidiospores originates monokaryons, characterized by having a single haploid nucleus per cell. In the field, eucalypts are associated with dykaryons of Pisolithus spp., there being no reports on the capacity of monokaryons to establish the ectomycorrhizal association with the host plant under such conditions. Although Pisolithus spp. monokaryons have been shown to form ectomycorrhizas in vitro, there is no information on the ability of these strains to promote nutrient uptake and growth of eucalypts. The […]

Eucalypt root growth and yield are affected directly by soil compaction during forestry operations, particularly harvesting. These effects are intensified under high soil moisture conditions. An experiment was carried out under controlled conditions in order to evaluate the effects of compaction under increased soil moisture levels, on seedling growth and nutrition. An oxidic-gibbsitic Red Yellow Latosol (LVA) and a kaolinitic Yellow Latosol (LA) were used. The treatments consisted of five compaction pressure levels (0, 60, 120, 180, and 240 kPa) and […]

Farm planning requires an assessment of the soil class. Research suggest that the Diagnosis and Recommendation Integrated System (DRIS) has the capacity to evaluate the nutritional status of coffee plantations, regardless of environmental conditions. Additionally, the use of DRIS could reduce the costs for farm planning. This study evaluated the relationship between the soil class and nutritional status of coffee plants (Coffea canephora Pierre) using the Critical Level (CL) and DRIS methods, based on two multivariate statistical methods (discriminant and […]

The knowledge of the dynamics of the organic N compound mineralization in the soil is important for the efficient use of N in agricultural production systems. With the objective of evaluating the protease activity and its relations to the contents of different N forms in a Dark Red Latosol cultivated with orange trees, soil samples were collected from two depths (0-10 and 10-20 cm) under top projection and between rows in the months of November and December 1998 and February and […]

The constant use of fertilizers that does not contain sulfur, in addition to low organic matter content of some soils, may result in sulfur limitation to crops. Due to the high mobility of the sulfate ion in many soils, it is important to know the residual effect of the phosphogypsum when added to the soil as S source, in order to estimate its application frequency. Experiments were performed under field conditions, in two years, in order to evaluate the effect […]

Under certain circumstances, Mn toxicity may be alleviated in mycorrhizal plants. Direct and indirect mechanisms can be involved in this process. Our objective was to evaluate the intrinsic effect of arbuscular mycorrhizal fungi (AMF) on the uptake and translocation of Mn by soybean plants. Initially, three AMF were tested to determine their capacity in enhancing plant growth under Mn excess. Glomus macrocarpum was most efficient at protecting plants against Mn excess, as a result of a higher Mn retention in […]

Aluminum tolerant wheat varieties can present increased efficiency of phosphorus use in presence of aluminum. A greenhouse experiment was conducted in 1994 to compare the wheat cultivars (Toropi) and (CNT 8), considered efficient and inefficient, respectively, in relation to phosphorus use. Nutrient solutions containing two phosphorus (1.6 and 32.3 µmol L-1) and two aluminum (0.0 and 37.0 µmol L-1) concentrations were tested. Root morphology and phosphate use were established for the plants, which were harvested from the pots on the 31th day. Roots of the Toropi […]