Heavy metals are a group of elements with specific features and natural occurrence in the environment, representing an accessory in the formation of rocks. These elements, although associated with toxicity, must be treated different from xenobiotics, since many metals are evidentially essentials (Fe, Mn, Cu, Zn, and Ni) and beneficial (Co) for plants. In this context, the objective was to determine the natural contents of the metals iron (Fe), manganese (Mn), zinc (Zn), nickel (Ni), copper (Cu) and cobalt (Co) […]

The Reference Quality Values (RQV) for heavy metals in soils are quite heterogeneous around the world. In Brazil, few studies establishing such values have been published. In the absence of VRQ of heavy metals in soils established for the specific conditions of the State of Espírito Santo, international generic values or values developed for other States are used. However, it should be noted that the use of these values can lead to erroneous assessments, due to the regional differences in […]

Changes in the pH of the rhizosphere of N2-fixing plants seem to play a key role in the uptake of micronutrient whose availability depends on changes in soil acidity. Variations in the B, Cu, Fe, Mn, and Zn uptake were studied during soybean development and growth cycle under the influence of biological N2 fixation and the initial pH of two soils samples (a clayey and a sandy Yellow Latosol; Oxisols), in a greenhouse experiment. These samples were incubated with rates […]

In Brazil, plant-available Zn in the soil is determined by several chemical procedures, of which the most commonly used are Mehlich-1 and DTPA. The objective of this study was to evaluate Zn availability in soils of Minas Gerais State, under different Zn and lime rates, using the extractors Mehlich-1, Mehlich-3 and DTPA and maize as indicator plant. Seven soil samples were incubated with lime to reach pH 6.0. The samples were treated with Zn in the form of ZnSO4, in […]

The concentrated suspension (CS), the basis of Mo trioxide, allows high Mo concentrations and is therefore a technical advance for seed treatment, since it allows the recommendation of the Mo at lower dosage than with the liquid solution formulations (LS). The purpose of this research was to evaluate the efficiency and doses of fertilizer with Mo and Co in concentrated suspension in comparison with liquid solution as well as fertilizers associated with phytohormones, applied in seed treatments, and their effect […]

The response to B in agricultural systems of sugar cane is still an unexplored issue; B application has however recently been widely publicized and used with a certain degree of frequency. The use of 10B-labeled fertilizers may further contribute to clarify this practice. With the objective of evaluating sugar cane use of B (10B) derived from fertilizer (boric acid), an experiment was conducted under field conditions in the 2005/2006 growing season. The experiment consisted of the installation of microplots (2 […]

The study of the efficiency of multielement extractant solutions to assess the availability of soil nutrients for plants has increased recently. The use of these solutions increases the efficiency of soil analysis laboratories by simplifying analytical procedures. Furthermore, the determination of nutrients by Inductively Coupled Plasma Optical Emission spectrometry (ICP-OES) has increased in recent years, owing mainly to simpler test procedures and less limitations in the detection of elements. Aiming at evaluating methods of extraction and verifying their efficiency to […]

Based on field observations it is often impossible to detect differences in soil B contents after the application of B fertilizers, even when increased leaf B contents are detected. This has raised doubts as to the efficacy of the B extractor used in routine soil B determinations. An experiment was conducted to study B extraction and availability to soybean in an Oxisol in the state of Mato Grosso. Boron (as boric acid) doses ranging from 0.0 to 10.0 kg ha-1 […]

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 […]

Research on B availability in soils is essential to assess the crops response to different concentrations of available B in soils. A greenhouse experiment was carried out aiming at studying the corn plant (Zea mays) response to B doses (0, 2, 4, 6, and 12 mg dm-3) applied to ten soils from the state of Pernambuco, Brazil. Available B was assessed by three extractants: hot water, HCl 0.05 mol L-1, and Mehlich-1. The critical and toxic levels were determined in soils and plants. Additionally, […]