402 results

Omission and Resupply of Nitrogen Affect Physiological and Enzymatic Activities and the Gene Expression of Eucalypt Clones

Loane Vaz Fernandes, Lílian Angélica Moreira, Nairam Félix de Barros, Cléberson Ribeiro, Júlio César Lima Neves

08/Dec/2016

ABSTRACT: The mineral nutrient uptake of plants in the field occurs in pulses, due to variations in the substance concentrations at the root surface. The fluctuations in nutrient supply probably induce changes in the plant, which are to date unknown for Eucalyptus. This study evaluated these changes in plant growth, nutritional status, photosynthesis, and gene expression, which can serve as biomarkers of the nitrogen status, of four eucalypt clones exposed to N omission and resupply. A greenhouse experiment with four […]

Rare Earth Element Concentrations in Brazilian Benchmark Soils

Ygor Jacques Agra Bezerra da Silva, Clístenes Williams Araújo do Nascimento, Yuri Jacques Agra Bezerra da Silva, Caroline Miranda Biondi, Cinthia Maria Cordeiro Atanázio Cruz Silva

08/Dec/2016

ABSTRACT: Studies regarding background concentrations of rare earth elements (REEs) are scarce and have mainly focused on a limited number of soil types from the northern hemisphere. The aim of this study was to determine REE concentrations in thirty-five benchmark soils of Brazil. Composite soil samples were taken from areas under native vegetation or with minimal anthropogenic influence. Concentrations of La, Ce, Pr, Nd, Sm, Eu, Gd, Yb, Lu, Dy, Er, Ho, Tb, Tm, Y, Sc, and Fe were determined […]

Phytoextractor Potential of Cultivated Species in Industrial Area Contaminated by Lead

Silvânia Maria de Souza Gomes Nascimento, Adailson Pereira de Souza, Vera Lúcia Antunes de Lima, Clístenes Williams Araújo do Nascimento, Joab Josemar Vitor Ribeiro do Nascimento

08/Dec/2016

ABSTRACT: High growth rate is one of the criteria used for the selection of species to be used in metal phytoextraction programs. This study was carried out to characterize the growth characteristics of sunflower (Helianthus annuus L.), castor bean (Ricinus communis L.), corn (Zea mays L), and vetiver [Vetiveria zizanioides (L.) Nash] grown on a soil contaminated with lead (Pb), with and without pH correction, to improve agronomic practices regarding phytoremediation programs. The experiment was designed as a randomized block […]

Nitrogen and Potassium Fertilization in a Guava Orchard Evaluated for Five Cycles: Soil Cationic Balance

Rafael Marangoni Montes, Léon Étienne Parent, Daniel Angelucci de Amorim, Danilo Eduardo Rozane, Sergie-Étienne Parent, William Natale, [...]

05/Oct/2016

ABSTRACT Soil fertility evaluation through soil analysis traditionally does not consider interaction among elements. To include the interaction effect in interpretation of soil analyses, an experiment was conducted to evaluate the effect of nitrogen fertilization (0, 0.5, 1.0, and 2.0 kg N per plant per cycle) with urea (45 % N) and potassium fertilization (0, 0.55, 1.1, and 2.2 kg K2O per plant per cycle) with potassium chloride (60 % K2O) on soil cationic balance. The experiment was carried out […]

Addition of Urease Inhibitor Has No Effect on Ammonia Volatilization Following Soil Application of Poultry Litter or Organomineral Fertilizer, Unlike Urea

Késia Silva Lourenço, Paulo Roberto Ernani, Juliano Corulli Corrêa, Sulian Junkes Dal Molin, Lucas Silva Lourenço

05/Oct/2016

ABSTRACT Quantification of ammonia volatilization after addition of animal residues and nitrogen (N) mineral fertilizers to the soil is important for N management in fertilization programs. The objective of this study was to evaluate the effect of adding a urease inhibitor to N fertilizers to minimize ammonia losses following soil application. The experiment was carried out in a laboratory with samples of a Brazilian Oxisol containing 790 g kg-1 clay and 23 g kg-1 organic matter. Treatments consisted of addition […]

Use of Organic Compost Containing Waste from Small Ruminants in Corn Production

Henrique Antunes de Souza, Maria Diana Melo, Anacláudia Alves Primo, Lucas Vasconcelos Vieira, Roberto Cláudio Fernandes Franco Pompeu, Fernando Lisboa Guedes, [...]

05/Oct/2016

ABSTRACT Composting is a useful way of transforming livestock waste into organic fertilizer, which is proven to increase soil nutrient levels, and thus crop yield. Remains from production and slaughter of small ruminants can become a source of important elements for plant growth, such as N, after microorganism-driven decomposition.The aim of this investigation was to evaluate the effects of this compost on soil fertility and on the nutritional status and yield of the corn crop. The experiment was conducted in […]

Soil Properties and Plant Biomass Production in Natural Rangeland Management Systems

Romeu de Souza Werner, Fabrício Tondello Barbosa, Ildegardis Bertol, Neuro Hilton Wolshick, Kristiana Fiorentin dos Santos, Josie Moraes Mota

05/Oct/2016

ABSTRACT Improper management of rangelands can cause land degradation and reduce the economic efficiency of livestock activity. The aim of this study was to evaluate soil properties and quantify plant biomass production in four natural rangeland management systems in the Santa Catarina Plateau (Planalto Catarinense) of Brazil. The treatments, which included mowed natural rangeland (NR), burned natural rangeland (BR), natural rangeland improved through the introduction of plant species after harrowing (IH), and natural rangeland improved through the introduction of plant […]

Soybean Tillage Systems and Physical Changes in Surface Layers of Two Albaqualf Soils

Gerson Meneghetti Sarzi Sartori, Enio Marchesan, Ricardo De David, Reimar Carlesso, Mirta Teresinha Petry, Núbia Pentiado Aires, [...]

05/Oct/2016

ABSTRACT A compacted subsurface soil layer can be a limiting factor for soybean growing, reducing soybean yield. The aim of this study was to evaluate the effect of different tillage systems on the physical properties of two Albaqualf soils of the Central Plains region in the state of Rio Grande do Sul in southern Brazil. Two experiments were conducted: one in Santa Maria, RS, during the 2013/14 and 2014/15 crop seasons, and another in Formigueiro, RS, during the 2013/14 crop […]

Iron Availability in Tropical Soils and Iron Uptake by Plants

Guilherme Furlan Mielki, Roberto Ferreira Novais, João Carlos Ker, Leonardus Vergütz, Gustavo Franco de Castro

05/Oct/2016

ABSTRACT Given the increase in crop yields and the expansion of agriculture in low fertility soils, deficiency of micronutrients, such as iron, in plants grown in tropical soils has been observed. The aim of this study was to evaluate Fe availability and Fe uptake by corn (Zea mays L.) plants in 13 different soils, at two depths. Iron was extracted by Mehlich-1, Mehlich-3, and CaCl2 (Fe-CC) and was fractionated in forms related to low (Feo) and high (Fed) crystallinity pedogenic […]

Sampling Layer for Soil Fertility Evaluation in Long-Term No-Tillage Systems

Renan Costa Beber Vieira, Sandra Mara Vieira Fontoura, Cimélio Bayer, Paulo Roberto Ernani, Ibanor Anghinoni, Renato Paulo de Moraes

05/Oct/2016

ABSTRACT In no-tillage (NT) systems, there is no plowed layer since the soil is not tilled. Thus, the soil layer for fertility evaluation can be defined as the one in which the fertility indices are affected by the surface application of lime and fertilizers and soil properties have the closest relationship with crop yields. The objective of this study was to determine the most appropriate soil layer under long-term NT for sampling for fertility evaluation in the South-Central region of […]

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