ABSTRACT Inoculation with arbuscular mycorrhizal fungi (AMF) is a strategy to improve the efficiency of forest plantations, reducing costs and increasing the survival of plant species. The objective of this study was to assess the response and mycorrhizal dependency of seedlings of the forest species Apuleia leiocarpa (Vogel) J.F. Macbr to inoculation with AMF. The experiment was conducted in a completely randomized design using a 5 × 5 factorial arrangement with six replications. The treatments consisted of combinations of five […]

ABSTRACT Ectomycorrhizal fungi (EMF) may improve the adaptation of eucalypts saplings to field conditions and allow more efficient fertilizer use. The effectiveness of EMF inoculum application in promoting fungal colonization, plant growth, nutrient uptake, and the quality of rooted cuttings was evaluated for Eucalyptus urophylla under commercial nursery conditions. For inoculated treatments, fertilization of the sapling substrate was reduced by 50 %. The experiment was carried out in a completely randomized design in a 4 × 4 factorial arrangement, wherein […]

Although the State of Parana, Brazil, has adopted crop rotation and no-till (NT) systems, fertilizer application is still based on recommendations developed more than 30 years ago for monocropping under conventional tillage because fertilizer recommendations developed specifically for crop rotation under NT are lacking. The objective of our study was to consolidate P calibration and evaluate crop responses to P fertilization so as to propose a system of technical recommendations for P fertilization for soybean, maize, wheat, and barley grown […]

Common bean is traditionally grown on small farms in Brazil, where animal wastes are often used as soil fertilizer. Since this is a short-cycle species, nutrients must be available soon after seed germination, which is not always the case when supplied in the form of organic fertilizers. This study was carried out to evaluate the efficiency of different poultry litters in comparison with mineral fertilizers to increase dry matter yield and nutrient release to beans. The experiment was conducted in […]

The use of genotypes with high biomass and nutrient accumulation but low nutrient harvest indices (ratio between nutrient amount in grains and in shoots) could reduce nutrient removal by harvesting and improve agricultural sustainability. The low variability found in the harvest indices in common bean (Phaseolus vulgaris L.) calls for the evaluation of a wide range of genotypes. This study evaluated the variability of nutrient harvest indices and their relationship with grain yield in common bean genotypes. A field experiment […]

Precision agriculture can increase efficiency and sustainability of grain crops in Brazil, especially in support of soil and crop management. In this study the importance of spatially-variable soil and crop attributes on the variability of grain crop yield and the use of this information to improve management decisions was examined. The study used data from the 2005/6 corn growing season of a 18 ha commercial field on a clayey Latossolo Bruno (FAO: Ferralsol). Soil (0-0.10 m layer) and crop properties […]

As a result of high flooded rice yields obtained in more recent years and the high crop response to fertilization in southern Brazil, fertilizer recommendations were flexibilized to meet different yield expectations. As these recommendations were poorly supported by research results, this study was conducted to evaluate the efficacy of these recommendations for the dry-seeded rice system in the rice cultivation regions of the State. Thirteen field experiments were conducted at nine locations: four in the 2004/2005 and nine in […]

Pasture is the main form of land use in Amazonia. Over time the pasture grass loses vigor and yields decrease, indicating a certain degree of degeneration. The main causes of degradation are lack of pasture maintenance and subsequent weed infestation, the choice of regionally unsuitable forage species and excessive grazing. The main purpose of this study was to evaluate the impact of different recovery managements on soil chemical properties and grass yield of a degraded pasture in Rondônia. For this […]

The use of animal manure in agricultural systems can cause water contamination and/or pollution by nutrients, especially by consecutive applications to the same area. In view thereof, the purpose of this study was to evaluate the effect of manure and fertilizer application on NH4+, NO3–, P and K leaching. For this evaluation, undisturbed soil columns were collected from a seven-year field experiment that consisted of 12 treatments, resulting from the combinations of four doses of dairy slurry with three doses […]

Eucalypt is highly efficient at growing in nutrient-poor soils, but little is known about the role of ectomycorrhizas and organic acids in nutrient uptake and storage under field conditions. Oxalic acid production and its relationships with Ca, P, K, and Mg concentrations were evaluated in the ectomycorrhizas and fine lateral roots of a 2.5 year-old Eucalyptus grandis x Eucalyptus urophylla hybrid grown in a mountainous area at Viçosa, MG, Brazil. Oxalic acid concentrations were also evaluated in rhizospheric, non-rhizospheric, and […]