In Brazil, plant-available micronutrients in the soil can be determined by several chemical extractants, the most common of which are dilute acid and chelating solutions. The purpose of this study was to assess the extractants 0.1 mol L-1 HCl, Mehlich-1, Mehlich-3 and DTPA for analysis of the micronutrients Cu, Zn, Fe, and Mn in soils from the state of Paraná. In samples from 12 soils (0-20 cm layer), wheat was planted (Triticum aestivum), grown for 42 days after emergence, and […]

The determination of nutrient absorption during the growth cycle is essential to determine the periods in which these elements are most required and the correct amounts that should be provided for potato, but for most cultivars used in Brazil the information is extremely scarce. The objective of this study was to evaluate absorption and exportation of the macronutrients N, P, K, Ca, Mg, and S by the potato cultivars Ágata, Asterix, Atlantic, Markies, and Mondial. The experiment was conducted in […]

Evaluation systems of agricultural land suitability are being used in different regions of Brazil, by distinct teams and with multiple applications. The objective of this study was to evaluate, for soils in the State of Acre, how different experts evaluate the relative importance of indicators of a land suitability system, and how they interpret properties that can define land suitability classes. Ten soil profiles analyzed for the IX Brazilian Soil Classification and Correlation Workshop were used. These soil profiles are […]

DRIS, an Diagnosis and Recommendation Integrated System, is a tool to evaluate the nutritional status of plants. Different DRIS formulas have been proposed to improve the efficiency of the crop nutrition diagnoses. The objective of this study was to compare the nutritional diagnosis of the formulas of Beaufils (1973), of Jones (1981) and of Elwali and Gascho (1984), based on the degree of agreement in commercial orchards of Theobrama grandiflorum trees. Leaf samples of 5 to 18 year-old cupuaçu trees […]

Knowledge of intensity-duration-frequency (IDF) relationships of rainfall events is extremely important to determine the dimensions of surface drainage structures and soil erosion control. The purpose of this study was to obtain IDF equations of 13 rain gauge stations in the state of Santa Catarina in Brazil: Chapecó, Urussanga, Campos Novos, Florianópolis, Lages, Caçador, Itajaí, Itá, Ponte Serrada, Porto União, Videira, Laguna and São Joaquim. The daily rainfall data charts of each station were digitized and then the annual maximum rainfall […]

The use of organic-mineral fertilizer produced by the manufacturing industry of lysine and threonine amino acids can improve the fertility of tropical soils. The objective of this study was to evaluate the influence of different doses of the organic-mineral fertilizer named Ajifer L-14 on chemical properties and on the response with increased production of a forage on a Red Latosol in the northwestern region of São Paulo State, Brazil. A randomized block design was used with seven treatments and four […]

The greatest limitation to the sustainability of no-till systems in Cerrado environments is the low quantity and rapid decomposition of straw left on the soil surface between fall and spring, due to water deficit and high temperatures. In the 2008/2009 growing season, in an area under center pivot irrigation in Selvíria, State of Mato Grosso do Sul, Brazil, this study evaluated the lignin/total N ratio of grass dry matter , and N, P and K deposition on the soil surface […]

Erodibility is an important factor for soil loss quantification, representing the processes that regulate water infiltration and soil resistance to the breakdown and transport of particles. Thus, by analyzing the spatial dependence of the principal components of erodibility (K-factor), aimed to estimate soil erodibility in a headwaters area in the watershed Córrego do Tijuco, Monte Alto, SP, and analyze the spatial variability of soil texture variables across the landscape. The mean erodibility of the area was high and the analysis […]

The techniques available for the remediation of environmental accidents involving petroleum hydrocarbons are generally high-cost solutions. A cheaper, practical and ecologically relevant alternative is the association of plants with microorganisms that contribute to the degradation and removal of hydrocarbons from the soil. The growth of three tropical grass species (Brachiaria brizantha, Brachiaria decumbens and Paspalum notatum) and the survival of root-associated bacterial communities was evaluated at different diesel oil concentrations. Seeds of three grass species were germinated in greenhouse and […]

More productive potato cultivars possibly require larger quantities of micronutrients, but in Brazil there is little information on extraction and exportation of micronutrients by the commonly used potato cultivars. The objective of this study was to evaluate extraction and exportation of micronutrients by the potato cultivars Ágata, Asterix, Atlantic, Markies, and Mondial. The experiment was conducted in Itaí, São Paulo State, Brazil, in the 2008 winter growing season on an Oxisol. Plots consisted of the five potato cultivars and subplots […]