Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2020 ( 1 )

2019 ( 25 )

2018 ( 22 )

2017 ( 24 )

Custom range...

Search Results: 1 - 10 of 12415 matches for " Reynaldo Campos Santana "
All listed articles are free for downloading (OA Articles)
Page 1 /12415
Display every page Item
Parametros fisiológicos de mudas de copaíba sob diferentes substratos e condi??es de sombreamento
Dutra, Tiago Reis;Massad, Marilia Dutra;Santana, Reynaldo Campos;
Ciência Rural , 2012, DOI: 10.1590/S0103-84782012005000048
Abstract: this research aimed to evaluate physiological parameters of seedlings of copaiba produced under the effect of different shading levels and types of substrates. the experiment lasted 130 days and was conducted in randomized blocks in factorial scheme 5x4 with five substrates: bioplant?, 70% vermiculite + 30% rice hulls, 40% vermiculite + 30% rice charred hulls + 30% fiber coconut, 50% vermiculite + 30% rice charred hulls + 20% sand, 70% vermiculite + 15% rice charred hulls + 15% vermicompost residue of textile industry; four shading levels (100, 70, 50 and 30% full sun) and three replications. the shade level of 50% compared to full sun, enabled the production of seedlings of copaiba with higher concentrations of chlorophyll b and total chlorophyll, and provided the lowest daily transpiration throughout the day and the plants. the leaf area, chlorophyll content and transpiration of seedlings of copaiba independent of the substrate and can be produced in any of the growth media evaluated.
Effect of NPK fertilization on production and leaf nutrient content of eucalyptus minicuttings in nutrient solution
Carvalho Neto, José Pereira;Silva, Enilson de Barros;Santana, Reynaldo Campos;Grazziotti, Paulo Henrique;
Revista Brasileira de Ciência do Solo , 2011, DOI: 10.1590/S0100-06832011000100023
Abstract: adequate nutrient levels in plants vary according to the species or clone, age and management practice. therefore, adjustments of the nutrient solution are often necessary according to the plant material for multiplication. this study aimed to evaluate the influence of npk fertilization on production and leaf nutrient contents of eucalyptus cuttings in nutrient solution. the study was conducted from november 2008 to january 2009 in a greenhouse. the experimental design was completely randomized fractional factorial (4 x 4 x 4)1/2, with a total of 32 treatments with three replications. the treatments consisted of four doses of n (50, 100, 200 and 400 mg l-1) as urea, p (7.5, 15, 30 and 60 mg l-1) in the form of phosphoric acid and k (50, 100, 200 and 400 mg l-1) in the form of potassium chloride in the nutrient solution. only the effect of n alone was significant for the number and dry weight of minicuttings per ministump, with a linear decreasing effect with increasing n levels. the highest number of cuttings was obtained at a dose of 50, 7.5 and 50 mg l-1 of n, p and k, respectively.
Desenvolvimento inicial de mudas de copaíba sob diferentes níveis de sombreamento e substratos
Dutra, Tiago Reis;Grazziotti, Paulo Henrique;Santana, Reynaldo Campos;Massad, Marília Dutra;
Revista Ciência Agron?mica , 2012, DOI: 10.1590/S1806-66902012000200015
Abstract: this study aimed to evaluate the influence of different shade levels and types of substrates in the initial development of seedlings of copaiba. the trial was conducted in a randomized block design in a factorial 5 x 4 with five substrates, bioplant?; 70% vermiculite + 30% rice hulls (70v+30ca), 40% vermiculite + 30% rice hulls + 30% coconut fiber (40v+30ca+30fc), 50% vermiculite + 30% rice hulls + 20% sand (50v+30ca+20a), 70% vermiculite + 15% bark carbonized rice + 15% vermicompost residue of textile industry (70v+15ca+15vc); four levels of shading (full sunlight (0%), 30, 50 and 70%) and three replications. we evaluated the following variables: absolute growth rate in height and diameter, survival, dry mass of leaves, stem and root, total dry mass, dry mass ratio of shoot and root dry weight, and leaf weight. the results show that the seedlings need shade copaiba in its early stage of development, and the level of 50% shading a viable alternative for production of its seedlings. the seedlings grown in copaiba 70v+30ca produced more total dry mass, while in bioplant? inferior characteristics observed for dry weight of leaves, total dry weight and leaf weight.
Parametros genéticos para caracteres de crescimento em pequizeiro em estádio precoce
Giordani, Samuel Cunha Oliveira;Fernandes, José Sebasti?o Cunha;Titon, Miranda;Santana, Reynaldo Campos;
Revista Ciência Agron?mica , 2012, DOI: 10.1590/S1806-66902012000100018
Abstract: genetic parameters estimated through statistical-genetic designs considering population and progeny effects are lacking for the pequi tree (caryocar brasiliense camb.). the aim of this study was to estimate genetic parameters and evaluate the efficiency of selection based on growth traits in the early stages. the experiment was carried out in carbonita, minas gerais, brazil, on january of 2005, using a randomized block design with 31 progenies, six replications and five plants per plot. from 2005 to 2008 the following traits were evaluated: plant height (in 2005; 2006; 2007 and 2008), stem diameter at ground level (in 2006; 2007; 2008) and crown diameter (in 2008). estimates for narrow-sense heritability at the individual level varied from 0.15 to 0.50. the genetic and phenotypic correlations between characteristics in the different years were positive and generally highly significant. estimates of the selection efficiency, obtained using the hamblin and zimmermann expression, ranged from medium to high for all traits. it was concluded that under the premise of a significant correlation between these traits and fruit production, selection for fruit production based on growth traits could be started at an early stage.
Eficiência de utiliza??o de nutrientes e sustentabilidade da produ??o em procedências de Eucalyptus grandis e Eucalyptus saligna em sítios florestais do estado de S?o Paulo
Santana, Reynaldo Campos;Barros, Nairam Félix de;Neves, Júlio Cézar Lima;
Revista árvore , 2002, DOI: 10.1590/S0100-67622002000400007
Abstract: nutrient use efficiency and growth of three provenances of eucalyptus grandis and three of e. saligna were evaluated, at 78 months of age, on various sites located in the counties of angatuba, itapetininga, paraibuna, s?o miguel arcanjo and s?o josé dos campos, in the state of s?o paulo, brazil. there was a variation in biomass production among sites, with the highest yield being obtained in s?o miguel arcanjo, followed by paraibuna. the other counties constituted a third group. the genetic materials revealed variations in nutrient use efficiency from site to site. e. grandis showed greater n, p, and mg nutrient use efficiency than e. saligna. there were no appreciable differences in efficiency between the two species for ca and k. high nutrient use efficiency is not necessarily related to high productivity. ca and k are the nutrients that could most limit productivity of the next rotation, when harvesting the stem. however, this limitation can be substantially reduced, especially for ca, if only stemwood is harvested.
Eficiência de utiliza o de nutrientes e sustentabilidade da produ o em procedências de Eucalyptus grandis e Eucalyptus saligna em sítios florestais do estado de S o Paulo
Santana Reynaldo Campos,Barros Nairam Félix de,Neves Júlio Cézar Lima
Revista árvore , 2002,
Abstract: A eficiência de utiliza o de nutrientes (EUN) e o crescimento de três procedências de Eucalyptus grandis e de três de E. saligna foram avaliados, aos 78 meses de idade, nos municípios de Angatuba, Itapetininga, Paraibuna, S o Miguel Aracanjo e S o José dos Campos, Estado de S o Paulo. Houve varia o na produ o de biomassa entre os municípios, sendo as maiores produtividades observadas em S o Miguel Aracanjo, seguido por Paraibuna, com os demais municípios constituindo um terceiro grupo. Dentro dos municípios n o houve diferen a entre materiais genéticos na produ o de biomassa, exceto em S o Miguel Arcanjo. Os materiais genéticos mostraram varia es na EUN entre locais. Observou-se maior EUN de E. grandis em rela o ao E. saligna para N, P e Mg, n o havendo diferen as apreciáveis de eficiência entre as duas espécies para Ca e K. A alta EUN n o está necessariamente ligada à alta produtividade. O Ca e o K s o os nutrientes que mais poder o limitar a produtividade do próximo ciclo, quando se considera a colheita do tronco. Entretanto, esta limita o pode ser substancialmente reduzida, principalmente para o Ca, se a colheita for realizada apenas do lenho.
Survival and growth of eucalypts clones seedlings in response to organic fertilizer application
Sula Janaína de Oliveira Fernandes,Miranda Titon,Reynaldo Campos Santana,Lucas Guimar?es Antonini
CERNE , 2011,
Abstract: This work aimed to evaluate the effect of Fert-Bokashi on survival and seedlings growth of two Eucalyptus urophylla clones propagated by minicutting technique. The experiment was conducted over a period of 28 days using a randomized block design and three replicates in an 6 x 2 factorial arrangement, with six Fert-Bokashi concentrations (0.0%, 0.1%, 0.3%, 0.5%, 0.7% and 0.9%) and two clones. Seedlings survival, height growth and shoot, root and total dry matter were evaluated. Experimental results demonstrated no significant effect of Fert- Bokashi on survival and seedlings growth of two Eucalyptus urophylla clones.
Influence of leaf area reduction on clonal production of eucalyptus seedlings
Reynaldo Campos Santana,Tiago Reis Dutra,José Pereira Carvalho Neto,Gilciano Saraiva Nogueira
CERNE , 2010,
Abstract: Clonal production of eucalyptus seedlings has made considerable progress in recent years. Significant developments havetaken place in irrigation and fertilization systems as well as in management of clonal miniorchards. However, the proportion of leaf area instem minicuttings remains almost the same as that used in macrocutting systems. This work aimed to evaluate the effect of leaf area reductionon seedling production of eight eucalyptus clones. The experiment was conducted over a period of 105 days using a randomized block designand three replicates in an 8 x 4 factorial arrangement, with eight clones and four leaf reduction levels (0%, 25%, 50% and 75%). Variablesevaluated included height, root collar diameter, shoot and root dry matter and relationships between these variables. Experimental resultsdemonstrated that clones behaved differently as to leaf reduction and that the 0% reduction level can be adopted in most clones beingevaluated.
Estima o de parametros genéticos e sele o de procedências e famílias de Dipteryx alata Vogel (baru) utilizando metodologia de REML/BLUP e E(QM)
Rodrigo Barros Rocha,Maria das Gra?as Barros Rocha,Reynaldo Campos Santana,Abadio Hermes Vieira
CERNE , 2009,
Abstract: The baru (Dipteryx alata Vogel, Faboideae Leguminosae) that occurs in Brazil Central is valued by its multiple uses. The objective of this study was to quantify the genetic variability of baru provenances and the genetic progress with the different selection strategies. The increase in total height was measured in progeny and provenance test of three years old using experimental random blocks design with plot information using six replications of ten plants per family with row spacing of 3 x 2m. There were no significant differences between the studied provenances and only “Santa Vitória”, “Capinópolis” and “Campina Verde” showed significativally genetic variability among progenies within provenances. The combined selection provided genetic gains of greater magnitude and accuracy. The low accuracy of the families selection of was mainly due to lack of genetic variability among families within some origins.
Aloca??o de nutrientes em plantios de eucalipto no Brasil
Santana, Reynaldo Campos;Barros, Nairam Félix de;Novais, Roberto Ferreira;Leite, Hélio Garcia;Comerford, Nicholas Brian;
Revista Brasileira de Ciência do Solo , 2008, DOI: 10.1590/S0100-06832008000700016
Abstract: forest management practices can alter nutrient exportation from the site. the purpose of this study was to estimate nutrient contents in the aboveground biomass of eucalyptus plantations in brazil. the influence of key climatic variables on eucalypt productivity and nutrient content was evaluated, using the database from the reserch programa on soil and eucalyptus nutrition of the soil science, departament - federal university of vi?osa, minas gerais state, brazil. climatic characteristics were an important component of the models. in regions with low water availability the nutrient accumulation in aboveground biomass as well as biomass production were lower. the highest proportion of all nutrients (68 % n, 69 % p, 67 % k, 63 % ca, and 68 % mg) was accumulated in the biomass within 4.5 years after planting for harvesting after approximately 6.5 years. after 4.5 years, the potential of fertilizer response was lower. canopy and stem bark together accounted for 65 % n, 70 % p, 64 % k, 79 % ca, and 79 % mg in the aboveground biomass. debarking in the field can therefore substantially reduce nutrient exportation and contribute to a more sustainable production in eucalyptus plantations.
Page 1 /12415
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.