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All publications of “Nairam Félix de Barros”

41 results

Tree Growth and Nutrient Dynamics in Pine Plantations in Southern Brazil

Nairam Felix de Barros, Mauro Valdir Schumacher, Júlio César Lima Neves, Nairam Felix de Barros, Samuel Vasconcelos Valadares

21/Nov/2017

ABSTRACT For the development of nutrient budget models to recommend lime and fertilizers for agricultural and forestry crops, curves of plant growth and nutrient accumulation are required. Information about how nutrients are partitioned between the different plant organs is also necessary, but still scarce for pine in Brazil. This study evaluated the growth, biomass partitioning, and nutrient dynamics in pine forests in southern Brazil. To this end, we assessed unthinned 2, 4, 6, and 8-year-old stands of Pinus taeda L. […]

Nutritional Efficiency of Eucalyptus Clones Under Water Stress

Caroline Müller, Bárbara Elias Reis Hodecker, Andrew Merchant, Nairam Félix de Barros

30/Oct/2017

Abstract Plant health and nutrition are strongly influenced by the availability of water. The objective of this study was to evaluate the different patterns of initial growth and nutritional efficiency of ten drought-stressed Eucalyptus clones. Water stress conditions were induced by osmotic stress, by gradual addition of polyethylene glycol 6000 over a 20-day period. Drought stress significantly reduced the dry matter of leaves, roots, and the whole plant as well as the nutritional efficiency of most clones. Clone PL040 was […]

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 […]

LEAF TOTAL NITROGEN CONCENTRATION AS AN INDICATOR OF NITROGEN STATUS FOR PLANTLETS AND YOUNG PLANTS OF EUCALYPTUS CLONES

Eric Victor de Oliveira Ferreira, Roberto Ferreira Novais, Bruna Maximiano Médice, Nairam Félix de Barros, Ivo Ribeiro Silva

01/Jul/2015

The use of leaf total nitrogen concentration as an indicator for nutritional diagnosis has some limitations. The objective of this study was to determine the reliability of total N concentration as an indicator of N status for eucalyptus clones, and to compare it with alternative indicators. A greenhouse experiment was carried out in a randomized complete block design in a 2 × 6 factorial arrangement with plantlets of two eucalyptus clones (140 days old) and six levels of N in […]

Differential Behavior of Young Eucalyptus Clones in Response to Nitrogen Supply

Eric Victor de Oliveira Ferreira, Roberto Ferreira Novais, Greice Leal Pereira, Nairam Félix de Barros, Ivo Ribeiro da Silva

01/May/2015

Eucalyptus requires large amounts of nitrogen (N); however, it responds in diverse manners to the application of this nutrient. The aim of this study was to evaluate the differential performance in growth, mineral nutrition, and gas exchanges of N-fertilized Eucalyptus clones. The treatments consisted of two Eucalyptus clones (VM-01 and I-144) and six N application rates (0, 0.74, 2.93, 4.39, 5.85, and 8 mmol L-1 NH4NO3) arranged in a randomized complete block design with five replications. VM-01 had greater plant […]

Effect of potassium fertilization on yield and nutrition of yerba mate (Ilex paraguariensis)

Delmar Santin, Eliziane Luiza Benedetti, Nairam Félix de Barros, Igor Carvalho de Almeida, Greice Pereira Leal, Lucas Fontes, [...]

01/Oct/2014

Yerba mate (Ilex paraguariensis) is a tree species native to the subtropical regions of South America, and is found in Brazil predominantly in the southern region. Despite the historical importance in this region, so far, studies on crop nutrition to improve yields are scarce. Thus, this study evaluated the effect of potassium rates on K soil availability, and the yield and nutritional status of yerba mate. The experiment was conducted in São Mateus do Sul, State of Paraná, on a […]

Effect of harvest residues management, soil tillage and fertilization on eucalyptus productivity

Frederico Alfenas Silva Valente Paes, Augusto Miguel Nascimento Lima, Rodrigo Eiji Hakamada, Nairam Félix de Barros

01/Aug/2013

Forestry companies have become increasingly concerned about the adoption of practices based on the conservation of soil and water. Thus, this study aimed to assess the impact of crop residue management, tillage and the use of industrial wastes on soil fertility and productivity of eucalyptus. The experiment started after clear-cutting of a commercial plantation of Eucalyptus grandis and the harvest residues were managed differently (removal of all residues; removal of bark and branches with diameter > 3.0 cm; and maintenance […]

Zinc availabity for eucalypt seedlings in Cerrado soils

Fernando Antonio Vieira Rodrigues, Nairam Félix de Barros, Júlio César Lima Neves, Víctor Hugo Alvarez V, Roberto Ferreira Novais

01/Aug/2012

In Brazil, along with the expansion of clonal forestry, the management of more productive and more nutrient-demanding genotypes has led to the appearance of micronutrient deficiency symptoms, mainly of boron (B), and more recently, of copper (Cu) and of zinc (Zn), especially in Cerrado areas. The purpose of this study was to evaluate three extraction solutions to determine Zn availability (Mehlich-1, Mehlich-3 and DTPA pH 7.3) for eucalyptus seedlings grown in a greenhouse, on six Cerrado soil samples, and to […]

Nitrogen balance in soil under eucalyptus plantations

Patrícia Anjos Bittencourt Barreto, Antonio Carlos da Gama-Rodrigues, Emanuela Forestieri da Gama-Rodrigues, Nairam Félix de Barros

01/Aug/2012

An understanding of the role of organic nitrogen (N) pools in the N supply of eucalyptus plantations is essential for the development of strategies that maximize the efficient use of N for this crop. This study aimed to evaluate the distribution of organic N pools in different compartments of the soil-plant system and their contributions to the N supply in eucalyptus plantations at different ages (1, 3, 5, and 13 years). Three models were used to estimate the contributions of […]

Effect of nitrogen rates and sources on eucalyptus yield and soil organic matter fractions in the cerrado region of Minas Gerais

Guilherme Luiz de Jesus, Nairam Félix de Barros, Ivo Ribeiro da Silva, Julio César Lima Neves, Eduardo Pinheiro Henriques, Vinicius Campos Lima, [...]

01/Feb/2012

In spite of the high amount of N accumulated in high-yielding, short-rotation eucalyptus plantations, no significant or consistent increases in trunk volume have been observed in response to N fertilization. This experiment evaluated the effect of N fertilization on the growth and chemical composition of eucalyptus as well as its role in soil organic matter (SOM) mineralization. The field experiment was carried out in a randomized block design with three replications, in Itamarandiba- MG. Two N sources (ammonium sulphate and […]

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