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Search Results: 1 - 10 of 179999 matches for " Vagner Tebaldi de;Lima "
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Análise de risco de contamina??o de águas superficiais e subterraneas por pesticidas em municípios do Alto Paranaíba - MG
Andrade, André Santana;Queiroz, Vagner Tebaldi de;Lima, Diego Tolentino de;Drumond, Luis César Dias;Queiroz, Maria Eliana Lopes Ribeiro de;Neves, Ant?nio Augusto;
Química Nova , 2011, DOI: 10.1590/S0100-40422011000700005
Abstract: a preliminary analyses of the possible contamination of surface and groundwater by the active ingredients of the pesticide products used in the areas with intensive agricultural activities of alto paranaíba region, mg, brazil, was carried out. the active ingredients and formulated products most used in the region were identified and their characteristics of environmental importance were presented. the epa screening criteria, the groundwater ubiquity score (gus) and the criteria proposed by goss were used to evaluate which pesticides might contaminate the local waters. among the active ingredients studied, several present risks to the local aquatic environment.
Toxicidade de óleo de mamona a Helicoverpa zea e a Trichogramma pretiosum
Bestete, Luziani Rezende;Pratissoli, Dirceu;Queiroz, Vagner Tebaldi de;Celestino, Flávio Neves;Machado, Lorena Contarini;
Pesquisa Agropecuária Brasileira , 2011, DOI: 10.1590/S0100-204X2011000800002
Abstract: the objective of this work was to evaluate the effects of castor bean oil on the tomato fruitworm, helicoverpa zea, and on the egg parasitoid trichogramma pretiosum. mortality of tomato fruitworm was determined for larvae subjected to castor bean oil ingestion and contact at concentrations 0.5, 1.0, 1.5, 2.0, 2.5 e 3.0% (v v-1). the castor bean oil action on t. pretiosum was determined by selectivity and susceptibility tests. the greatest larvae mortalities were observed in the treatment by contact with the lowest concentrations (0.5 and 1.0%), while at intermediate concentrations (1.5, 2.0, and 2.5%) there were no differences between the ways of application. at the highest tested concentration of castor bean oil (3.0%), the ingestion treatment caused a higher mortality, in comparison to the treatment by contact. the number of eggs parasitized by t. pretiosum was negatively affected by castor bean oil in the selectivity test; however, other evaluated parameters for selectivity and susceptibility were not affected. castor bean oil reduces survival of h. zea larvae both by ingestion and contact. in addition, it does not affect the development of t. pretiosum, since sprayings are performed after releasing of the parasitoid.
Insecticidal activity of citronella grass essential oil on Frankliniella schultzei and Myzus persicae Atividade inseticida do óleo essencial de capim-citronela sobre Frankliniella schultzei e Myzus persicae
Patrícia Fontes Pinheiro,Vagner Tebaldi de Queiroz,Vando Miossi Rondelli,Adilson Vidal Costa
Ciência e Agrotecnologia , 2013,
Abstract: The thrips, Frankliniella schultzei, and green peach aphid, Myzus persicae, cause direct damage to plants of economic importance and transmit phytoviruses, causing large economic losses. Chemical constituents of essential oils present a wide range of biological activities. The aim of this work was to evaluate insecticidal activity of essential oil from citronella grass, Cymbopogon winterianus, on F. schultzei and M. persicae. This essential oil was obtained by steam distillation and components were identified by GC/FID and GC/MS. A Potter spray tower was used to spray insects with the essential oil. The major constituents are geraniol (28.62%), citronellal (23.62%) and citronellol (17.10%). Essential oil of C. winterianus at 1% (w v-1) causes mortality in F. schultzei and M. persicae at 34.3% and 96.9%, respectively. The LC50 value for M. persicae was 0.36% and LC90 0.66%. Thus, citronella grass essential oil at 1% (w v-1) is more toxic to M. persicae than F. schultzei. This essential oil shows promise for developing pesticides to manage M. persicae. O tripes, Frankliniella schultzei, e o pulg o-verde, Myzus persicae, além de causarem danos diretos a plantas de importancia econ mica, também s o importantes transmissores de fitoviroses, acarretando grandes perdas econ micas. Os constituintes químicos dos óleos essenciais têm sido cada vez mais estudados, pois apresentam uma ampla gama de atividades biológicas. Neste trabalho, objetivou-se avaliar a atividade inseticida do óleo essencial de capim-citronela, Cymbopogon winterianus, sobre F. schultzei e M. persicae. O óleo essencial foi obtido por hidrodestila o e a identifica o dos seus componentes foi realizada por CG/DIC e CG/EM. Uma torre de Potter foi utilizada para pulverizar os insetos com óleo essencial. Os componentes majoritários encontrados s o geraniol (28,62%), citronelal (23,62%) e citronelol (17,10%). O óleo essencial de C. winterianus a 1% (m v-1) causa mortalidade de F. schultzei e M. persicae em 34,3% e 96,9%, respectivamente. O valor estimado de CL50 para M. persicae foi 0,36% e CL90 de 0,66%. Assim, o óleo essencial de capim-citronela a 1% (m v-1) é mais tóxico para M. persicae do que para F. schultzei. Este óleo essencial mostra-se promissor para o desenvolvimento de inseticidas para o manejo de M. persicae.
Determina??o da pureza varietal de sementes de soja com o auxílio de marcadores moleculares microssatélites
Schuster, Ivan;Queiroz, Vagner Tebaldi de;Teixeira, Arlindo Inês;Barros, Everaldo Gon?alves de;Moreira, Maurilio Alves;
Pesquisa Agropecuária Brasileira , 2004, DOI: 10.1590/S0100-204X2004000300007
Abstract: environmental factors contribute for production of soybean seeds with different characteristics from the standard pattern of a determined variety. dna markers can contribute for the identification of genetic seed purity, once these type of markers are not influenced by the environment. the objective of this work was to evaluated a method for analysis of soybean seed genetic purity by using microsatellites markers. dna samples from soybean seeds considered atypical by the visual method were analyzed by microsatellites and compared with the typical variety pattern. dna samples were analyzed in bulks, reducing costs but keeping the same precision as the one obtained in the individual analysis. from eleven seed lots classified as contaminated by the visual method, and therefore eliminated through certification, only four were shown to present a number of contaminating seeds above the accepted limit trough dna analysis.
Determina??o do ponto de névoa em surfactantes n?o i?nicos por espectroscopia de impedancia elétrica
Lima, Sandro Vagner de;Oliveira, Helinando Pequeno de;
Química Nova , 2010, DOI: 10.1590/S0100-40422010000900020
Abstract: in this paper, we analyze the use of electrical impedance spectroscopy applied to determination of cloud point. the slope of admittance measured at 100 khz is reduced to temperature above the critical value which characterizes the phase transition, in a strong indication that this process is activated during the clouding. additionally to this study we explored the influence of parameters such as additives and temperature on the performance of phase separation of residues (silver nanoparticles) by cloud point extraction. the interaction with salt maximizes the separation of chemical residues in a progressively reduced temperature.
Helminthological records of six-banded armadillos Euphractus sexcinctus (Linnaeus, 1758) from the Brazilian semi-arid region, Patos county, Paraíba state, including new morphological data on Trichohelix tuberculata (Parona and Stossich, 1901) Ortlepp, 1922 and proposal of Hadrostrongylus ransomi nov. comb.
Hoppe, EGL.;Araújo de Lima, RC.;Tebaldi, JH.;Athayde, ACR.;Nascimento, AA.;
Brazilian Journal of Biology , 2009, DOI: 10.1590/S1519-69842009000200027
Abstract: this work aimed to evaluate the gastrointestinal helminthfauna composition of six-banded armadillos from the brazilian semi-arid region. gastrointestinal contents of six road-killed adult animals from patos county, paraíba state, were analyzed. six species of nematodes, comprising five genera and four families, were recovered from the analyzed animals. new morphological data on trichohelix tuberculata is given, along with a new taxonomical proposal for hadrostrongylus ransomi (travassos, 1935) n. comb. this is the first record for parasitic helminths in this host from the brazilian semi-arid.
Regulation of Pollen Foraging Activity in Apis mellifera Africanized Honeybees Colonies  [PDF]
Erica Gomes de Lima, Simone Cristina Camargo, Pedro da Rosa Santos, Jose Washington Santos Oliveira, Vagner de Alencar Arnaut de Toledo
Agricultural Sciences (AS) , 2016, DOI: 10.4236/as.2016.76034
Abstract: Efficient honey production requires knowledge about the behavior of the workers and the parameters that influence the strength of the colony. In this study, the objective was to analyze the interaction between the foraging behavior of worker honeybees and pollen storage levels in Africanized honeybees colonies. Colonies with low pollen storage increased pollen intake rates, but this value was 15% lower than colonies with high pollen storage, demonstrating a direct relationship between the pollen storage levels and foraging activity. The difference in pollen intake rates varied according to the number of foraging honeybees and pollen load collected by each individual. Under both high and low pollen storage, colonies returned pollen storage to initial level within 16 days, suggesting that honeybees regulate pollen storage levels around a homeostatic set point. Relationship between pollen storage levels and colony brood production was also found, indicating how alterations in the behavior of each individual can affect the strength of the colony.
Incidência e controle químico da ferrugem da goiabeira em diferentes épocas de poda na regi?o norte do Espírito Santo
Martins, Marlon Vagner Valentim;Serrano, Luiz Augusto Lopes;Lima, Inorbert de Melo;Oliveira, Erik Bravim de;
Revista Ceres , 2012, DOI: 10.1590/S0034-737X2012000200005
Abstract: in the north of espírito santo state, brazil, increasing occurrence of rust (puccinia psidii g. winter) has been observed in guava trees, causing fruit drop and yield losses. the objective of this work was evaluate the incidence and chemical control of guava rust in 'paluma' guava trees pruned in different seasons. three experiments were carried out in a randomized complete block design, with three different pruning times (january; may and october) and four fungicide spraying treatments (i - untreated check, ii - copper oxychloride, iii - tebuconazole and iv - tebuconazole + oxychloride copper). plants pruned in january showed the highest maximum and final guava rust incidences and smallest number of fruits per plant. regardless of pruning time, the effective rust control occurred in plants sprayed with tebuconazole and tebuconazole plus copper oxychloride fungicides. four sprayings with tebuconazole pure or mixed with copper oxychloride were sufficient to mitigate the damage caused by guava rust.
Small mammal community structure and microhabitat use in the austral boundary of the Atlantic Forest, Brazil
Lima, Daniela O. de;Azambuja, Bethania O.;Camilotti, Vagner L.;Cáceres, Nilton C.;
Zoologia (Curitiba) , 2010, DOI: 10.1590/S1984-46702010000100015
Abstract: we investigated the richness, composition, and species relative abundance of a terrestrial small mammal community in a deciduous forest area in the austral boundary of the atlantic forest. the microhabitat use of the most common species was also investigated. six rodents - akodon montensis (thomas, 1913), oligoryzomys nigripes (olfers, 1818), sooretamys angouya (thomas, 1913), thaptomys nigrita (lichtenstein, 1829), mus musculus (linnaeus, 1758) and juliomys sp. - and one marsupial - didelphis albiventris (lund, 1840) - were captured. thaptomys nigrita is recorded in the state of rio grande do sul for the first time. species richness was poor when compared with communities in the central portions of the atlantic forest, but equivalent to that found in the araucaria and dense ombrophilous forests of southern brazil. the species most often captured in our study, a. montensis and o. nigripes, are also the most common in the majority of faunistic studies carried out in the atlantic forest. akodon montensis and s. angouya used places with high abundance of bamboo, possibly to avoid predators. oligorizomys nigripes used areas with a high density of scrubs, what could facilitate aboveground movements, and was negatively correlated to mature forest indicators, which reinforce the idea that this species has opportunistic habits.
épocas e intensidades de poda de frutifica??o na goiabeira ' Paluma' , em Pinheiros-ES
Serrano, Luiz Augusto Lopes;Martins, Marlon Vagner Valentim;Lima, Inorbert de Melo;Marinho, Cláudia Sales;Tardin, Flávio Dessaune;
Revista Brasileira de Fruticultura , 2008, DOI: 10.1590/S0100-29452008000400026
Abstract: the objective of this work was to evaluate the effects of different pruning times and intensities on the phenology and yield of 'paluma' guava trees, in pinheiros, espírito santo state, brazil. the plants were submitted to three pruning intensities (heavy, medium and light), in four dates (november 25, 2005; december 21, 2005; january 27, 2006 and february 23, 2006). the period between pruning and the beginning of fruit ripening varied from 189 (pruning in november and december) to 203 days (pruning in february). regardless of pruning time, the larger numbers of buds and established branches occurred in plants submitted to light pruning. plants submitted to heavy pruning produced the smallest numbers of buds, established branches and fruits per plant, as well as the smallest index of fruit sets and yield; however they produced higher fruit weight. the largest yield and number of fruits per plant occurred in plants pruned in february. the time and intensity of pruning affect 'paluma' guava tree sprout and yield.
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