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Pesquisa : B01.650.160 [Categoria DeCS]
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Id: lil-555549
Autor: Resende, Osvaldo; Rodrigues, Silvestre; Siqueira, Valdiney Cambuy; Arcanjo, Renan Vieira.
Título: Cinética da secagem de clones de café (Coffea canephora Pierre) em terreiro de chão batido / Kinetics of coffee berry clones drying (Coffea canephora Pierre) in ground pavement
Fonte: Acta amaz;40(2):247-255, 2010. graf, tab.
Idioma: pt.
Resumo: Objetivou-se com o presente trabalho estudar a cinética da secagem de quatro clones de café da espécie Coffea canephora submetidos à secagem em terreiro de chão batido, bem como ajustar diferentes modelos matemáticos aos valores experimentais selecionando aquele que melhor representa o fenômeno em estudo. Foram utilizados frutos de café dos clones: Cpafro 194, Cpafro 193, Cpafro 167 e Cpafro180, colhidos com os teores de água iniciais de 1,20; 1,32; 1,51 e 1,46 (decimal base seca (b.s.)), respectivamente. A secagem prosseguiu em terreiro de chão batido até que o produto atingisse o teor de água de 0,137; 0,133; 0,142 e 0,140 (decimal b.s.) respectivamente para os clones Cpafro 194, Cpafro 193, Cpafro 167 e Cpafro 180. Aos dados experimentais foram ajustados dez modelos matemáticos citados na literatura específica e utilizados para representação do processo de secagem de produtos agrícolas. Baseando-se em parâmetros estatísticos, conclui-se que os modelos Verma, Dois Termos e Aproximação da Difusão foram adequados para representação da secagem dos quatro clones de café analisados, e além destes, para o clone Cpafro 167, os modelos Thompson, Page, Newton, Logarítmico, Henderson e Pabis e Exponencial de Dois Termos também se mostraram satisfatórios na descrição do fenômeno; já o tempo necessário para a secagem em terreiro de chão batido dos clones de café Cpafro 194, Cpafro 193, Cpafro 167 e Cpafro 180 foi de 189,5 h.

The objective of this work was to study the drying kinetics of four coffee berry clones Coffea canephora species dried in ground pavement and to fit different mathematical models to different experimental data selecting the one that best represents the phenomenon. Have been used coffee berry of clones: Cpafro 194, Cpafro 193, Cpafro 167 and Cpafro 180, harvested at moisture content of 1.20; 1.32; 1.51 e 1.46 (decimal d.b.), respectively. The drying continued in ground pavement until achieved the moisture content of 0.13 (decimal d.b.). Ten mathematical models cited in the literature were fitted to the experimental data in order to represent the drying process. Based on the statistical parameters it can be concluded that the Verma, Dois Termos and Aproximação da Difusão models represent well the drying of four coffee berry clones, and beyond these for the clone Cpafro 167, the Thompson, Page, Newton, Logarítmico, Henderson e Pabis and Exponencial de Dois Termos models also shown in satisfactory description of the phenomenon; the drying time in ground pavement of coffee berry clones Cpafro 194, Cpafro 193, Cpafro 167 and Cpafro 180, until the moisture content of 0.13 (decimal d.b.) was 189.5 hours.
Descritores: Estado de Hidratação do Organismo
Modelos Anatômicos
-Produtos Agrícolas
Responsável: BR6.1 - BCS - Biblioteca de Ciências da Saúde


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Id: lil-555555
Autor: Sena, Juliana dos Santos; Tucci, Carlos Alberto Franco; Lima, Hedinaldo Narciso; Hara, Francisco Adilson dos Santos.
Título: Efeito da calagem e da correção dos teores de Ca e Mg do solo sobre o crescimento de mudas de angelim-pedra (Dinizia excelsa Ducke) / Liming effect and correction of the Ca and Mg contents of the soil on angelim-pedra (Dinizia excelsa Ducke) seedling growth
Fonte: Acta amaz;40(2):309-317, 2010. ilus, graf, tab.
Idioma: pt.
Resumo: O conhecimento dos requerimentos nutricionais das espécies e de suas respostas à correção do substrato é fundamental para a produção de mudas de qualidade. O objetivo deste trabalho foi avaliar o efeito de diferentes tipos de calcário e da correção da deficiência de Ca e Mg sobre o desenvolvimento de mudas de angelim-pedra (D. excelsa) em casa de vegetação, utilizando-se como substrato Latossolo Amarelo. Foram testados três tipos de calcário e fornecimento de Ca e Mg por meio de fontes não-corretivas da acidez em três relações Ca:Mg. Os tratamentos consistiram de T0 & testemunha; T1 & calcário dolomítico; T2 & calcário magnesiano; T3 & calcário calcítico; T4 & Ca e Mg na relação 3:1; T5 & Ca e Mg na relação 9:1; e T6 & Ca e Mg na relação 15:1. O delineamento experimental foi de blocos ao acaso, com cinco repetições, totalizando 35 parcelas, cada uma delas com 3 mudas. O substrato foi adubado com doses equivalentes a 100-250-150 e 15 kg ha-1 de N, P2O5, K2O e S, respectivamente e com solução de micronutrientes (3 mL de Chelamix L-1 de água destilada). Foram avaliadas: a altura da planta, o diâmetro do colo, matéria seca da parte aérea, matéria seca da raiz, matéria seca total, relação raiz/parte aérea e conteúdos de nutrientes da parte aérea das plantas. De modo geral, a aplicação de calcário favoreceu o crescimento de D. excelsa, sendo os melhores resultados obtidos com a aplicação de calcário magnesiano na relação 9:1.

Knowledge of nutritional requirements of the species and their answers to correcting the substratum is fundamental for the production of quality seedlings. In this work, we aimed to evaluate the effect of different limestone types and the correction of Ca and Mg deficiency on the development of angelim-pedra (Dinizia excelsa) seedlings, under glasshouse conditions. We tested three types of limestone and three types of Ca:Mg provisioning on a Yellow Oxisol (with non-corrective acidity sources): T0 & control; T1 & soil limed with dolomitic lime (3:1); T2 & soil limed with magnesium lime (9:1); T3 & soil limed with calcitic lime (15:1); T4 & a mixture of calcium and magnesium, in the 3:1 proportion; T5 & calcium and magnesium, in the 9:1 proportion; and T6 & calcium and magnesium, in the 15:1 proportion. The experimental design was of random blocks, with 5 repetitions, totaling 35 parcels with 3 seedlings each. The substratum was fertilized with doses equivalent to 100-250-150 and 15 k ha-1 of N, P2O5, K2O and S respectively, and micronutrient solution (3 mL of Chelamix L-1 of distilled water). We evaluated the height, diameter of the stem, dry biomass of the aerial part, dry biomass of the root, dry biomass of the drought, aerial part/root relation and nutrient contents of the aerial part of the plants. The limestone application affected positively the height, the diameter, the matter total biomass and the absorption of Ca of the D. excelsa seedlings (p<0,05). The application of magnesium lime with Ca:Mg 9:1 proportion showed the best results.
Descritores: Produtos Agrícolas
Responsável: BR6.1 - BCS - Biblioteca de Ciências da Saúde


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Id: biblio-1121039
Autor: Licona, Laura Stefany; Estupiñán, Luis Hernando.
Título: BARBECHO COMO PRÁCTICA CULTURAL: UNA REVISIÓN HISTÓRICA Y ALCANCES FRENTE A LA SOSTENIBILIDAD / FALLOW LAND AS A CULTURAL PRACTICE: A HISTORICAL REVIEW AND SCOPE AGAINST SUSTAINABILITY
Fonte: Rev. luna azul;49:[21]-[37], Julio 01, 2019.
Idioma: es.
Resumo: Introducción. El rápido aumento de la producción agrícola, las actividades extractivas y la expansión demográfica han originado degradación del suelo y la modificación del equilibrio dinámico propio de un ecosistema debido, entre otras cosas, a un cambio drástico en las formas tradicionales de agricultura como la disminución de periodos de descanso entre cultivos o barbecheo. Objetivo. Describir la dinámica de barbecho desde su origen, así como su influencia en el uso y transformación del suelo desde el punto de vista ambiental en un contexto histórico. Metodología. El método utilizado fue la consulta en bases de datos de revistas indizadas utilizando palabras claves como: barbecho, descanso, suelo, prácticas culturales andinas, prácticas agroculturales, agricultura tradicional y páramo; sin descartar artículos por fecha de publicación. Resultados. La evidencia encontrada en la literatura científica apunta que el barbecho es una práctica cultural tradicional que puede ser un modelo apropiado para el diseño de agroecosistemas, favoreciendo positivamente las condiciones ambientales y la sostenibilidad de ecosistemas estratégicos, como es el caso particular de los páramos cuya vocación primaria es la conservación.

Introduction: The rapid increase in agricultural production, extractive activities and demographic expansion have caused soil degradation and the modification of the dynamic equilibrium of an ecosystem due, among other things, to a drastic change in traditional forms of agriculture such as the decrease in rest periods between crop and fallow land. Objective: To describe the fallow land dynamics from its origin, as well as its influence on the use and transformation of the soil from the environmental point of view in a historical context. Methodology: The method used was the consultation in databases of indexed journals using keywords such as: fallow, rest, soil, Andean cultural practices, agricultural practices, traditional agriculture and paramo without discarding articles by publication date. Results: The evidence found in the scientific literature indicates that fallow is a traditional cultural practice that can be an appropriate model for the design of agroecosystems favoring positively environmental conditions and the sustainability of strategic ecosystems, as is the case of the paramos, whose primary vocation is conservation.
Descritores: Produtos Agrícolas
Responsável: CO54.1 - Centro de Biblioteca e Información Científica


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Id: biblio-886665
Autor: MARTINS, KARLA V; DOURADO-NETO, DURVAL; REICHARDT, KLAUS; FAVARIN, JOSÉ L; SARTORI, FELIPE F; FELISBERTO, GUILHERME; MELLO, SIMONE C.
Título: Maize dry matter production and macronutrient extraction model as a new approach for fertilizer rate estimation
Fonte: An. acad. bras. ciênc;89(1,supl):705-716, May. 2017. tab, graf.
Idioma: en.
Resumo: ABSTRACT Decision support for nutrient application remains an enigma if based on soil nutrient analysis. If the crop could be used as an auxiliary indicator, the plant nutrient status during different growth stages could complement the soil test, improving the fertilizer recommendation. Nutrient absorption and partitioning in the plant are here studied and described with mathematical models. The objective of this study considers the temporal variation of the nutrient uptake rate, which should define crop needs as compared to the critical content in soil solution. A uniform maize crop was grown to observe dry matter accumulation and nutrient content in the plant. The dry matter accumulation followed a sigmoidal model and the macronutrient content a power model. The maximum nutrient absorption occurred at the R4 growth stage, for which the sap concentration was successfully calculated. It is hoped that this new approach of evaluating nutrient sap concentration will help to develop more rational ways to estimate crop fertilizer needs. This new approach has great potential for on-the-go crop sensor-based nutrient application methods and its sensitivity to soil tillage and management systems need to be examined in following studies. If mathematical model reflects management impact adequately, resources for experiments can be saved.
Descritores: Produtos Agrícolas/crescimento & desenvolvimento
Zea mays/crescimento & desenvolvimento
Fertilizantes/análise
-Biomassa
Modelos Biológicos
Responsável: BR1.1 - BIREME


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Id: biblio-886819
Autor: ARRUDA, MURILO R DE; GILLER, KEN E; SLINGERLAND, MAJA.
Título: Where is sugarcane cropping expanding in the brazilian cerrado, and why? A case study
Fonte: An. acad. bras. ciênc;89(3,supl):2485-2493, 2017. tab, graf.
Idioma: en.
Resumo: ABSTRACT Sugarcane growing area in Brazil sharply expanded between 2000 and 2010 due to the increasing world demand for sugar and ethanol. Since this expansion of sugarcane is said to occur in areas covered by degraded pastures, it is likely not threatening the environment or food production. In order to verify this assumption, we investigate at farm and field levels which types of land use sugarcane cropping replaced between 2005 and 2010 and the reasons for farmers shifting or not shifting to sugarcane, as a case study in two counties in the state of Goiás. Within the studied period, sugarcane cropping expansion was related to large farms, lower risk perceived by farmers, and higher profitability compared with soybean and beef cattle-raising. For smallholders, particularly dairy farmers, the need to comply with the set-aside rules under Brazilian Forest Code (Código Florestal Brasileiro) made a shift to sugarcane less attractive, as it would have forced them to reduce farm cultivable area, with loss of incomes. From 30,408 ha under sugarcane surveyed, 45.7% had used to be pastures, 31% had previously been pastures rotated with soybean and maize, and 23.3% had been cropped exclusively with soybean or maize.
Descritores: Produtos Agrícolas/crescimento & desenvolvimento
Saccharum/crescimento & desenvolvimento
Agricultura/economia
Agricultura/legislação & jurisprudência
Agricultura/métodos
Agricultura/estatística & dados numéricos
-Brasil
Entrevistas como Assunto
Responsável: BR1.1 - BIREME


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Id: biblio-886634
Autor: WANDSCHEER, ALANA C D; MARCHESAN, ENIO; SANTOS, SANDRO; ZANELLA, RENATO; SILVA, MARÍLIA F; LONDERO, GUILHERME P; DONATO, GABRIEL.
Título: Richness and density of aquatic benthic macroinvertebrates after exposure to fungicides and insecticides in rice paddy fields
Fonte: An. acad. bras. ciênc;89(1):355-369, Jan,-Mar. 2017. tab.
Idioma: en.
Resumo: ABSTRACT The objective of this study was to verify the richness and density of aquatic benthic macroinvertebrates after exposure to fungicides and insecticides of the rice paddy fields. In the crop seasons of 2012/13 and 2013/14, field experiments were performed, which consisted of single-dose applications of the fungicides trifloxystrobin + tebuconazole and tricyclazole, and the insecticides lambda-cyhalothrin + thiamethoxam and diflubenzuron, in 10 m2 experimental plots, over rice plants in the R3 stage. Control plots with and without rice plants were maintained in order to simulate a natural environment. Soil samples were collected during rice cultivation for assessment of the macroinvertebrate fauna. Chemical-physical parameters assessed in the experiments included temperature, pH and oxygen dissolved in the water and pesticide persistence in the water and in the soil. The application of a single dose of the pesticides and fungicides in the recommended period does not cause significant negative effects over the richness and density of the macroinvertebrates. Tebuconazole, tricyclazole and thiamethoxam showed high persistence in the irrigation water of rice paddy fields. Thus, the doses and number of applications of these products in crops should be carefully handled in order to avoid contamination of the environment.
Descritores: Oryza
Produtos Agrícolas
Áreas Alagadas
Fungicidas Industriais/toxicidade
Inseticidas/toxicidade
Invertebrados/efeitos dos fármacos
-Valores de Referência
Solo/química
Fatores de Tempo
Qualidade da Água
Água/química
Monitoramento Ambiental
Análise de Variância
Estatísticas não Paramétricas
Invertebrados/crescimento & desenvolvimento
Limites: Animais
Responsável: BR1.1 - BIREME


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Id: biblio-886681
Autor: WANDSCHEER, ALANA C D; MARCHESAN, ENIO; TEDESCO, SOLANGE B; FRESCURA, VIVIANE DAL-SOUTO; SOARES, CAMILLE F; LONDERO, GUILHERME P; TELÓ, GUSTAVO M; HANSEL, DÂMARIS S S.
Título: Cytogenotoxicity of rice crop water after application of the tricyclazole fungicide
Fonte: An. acad. bras. ciênc;89(2):1251-1258, Apr.-June 2017. tab, graf.
Idioma: en.
Projeto: Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq).
Resumo: ABSTRACT Tricyclazole is currently one of the fungicides recommended for the treatment of diseases in irrigated rice. However, there is relatively little information on its cytotoxic and genotoxic potential. The objective of this study was to evaluate the cytotoxicity and genotoxicity of rice crop water after apllication of the tricyclazole fungicide through the Allium cepa L. test. The rice crop water samplings were collected before and 1, 15 and 30 days after application of the fungicide in rice plant shoots. The Allium cepa roots were placed in contact with the rice crop water to check for possible chromosomal abnormalities and mitotic index of the bioindicators meristematic cells. The data obtained by the Allium cepa test indicates that the application of the tricyclazole fungicide leads to an increase in the genotoxic activity in the rice crop water, through the appearance of chromosomal abnormalities, without, however, causing significant effects on the mitotic index. The major chromosomal alterations observed were anaphasic and telophasic bridges and laggard chromosomes.
Descritores: Oryza/efeitos dos fármacos
Cebolas/efeitos dos fármacos
Fungicidas Industriais
-Oryza/genética
Poluentes Químicos da Água/toxicidade
Dano ao DNA
Aberrações Cromossômicas/induzido quimicamente
Produtos Agrícolas
Produtos Agrícolas/genética
Irrigação Agrícola
Mitose/efeitos dos fármacos
Índice Mitótico
Testes de Mutagenicidade/métodos
Tipo de Publ: Estudo de Avaliação
Responsável: BR1.1 - BIREME


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Id: biblio-886757
Autor: ALMEIDA, RODRIGO E M DE; OLIVEIRA, SILAS M DE; LAGO, BRUNO C; P JUNIOR, CLOVIS; TRIVELIN, PAULO C O; FAVARIN, JOSÉ L.
Título: Palisadegrass effects on N fertilizer dynamic in intercropping systems with corn
Fonte: An. acad. bras. ciênc;89(3):1917-1923, July-Sept. 2017. tab, graf.
Idioma: en.
Resumo: ABSTRACT Corn grain yield, nitrogen (N) fertilizer efficiency and distribution to corn alone and three forms of corn and palisadegrass (Urochloa spp.) intercropping implantation was investigated. A field experiment with 15N labeling fertilizer was performed in randomized block design. No form of palisadegrass intercropping implantation affected corn grain yield, total N accumulation and N use efficiency (NUE), which were 8.7 t ha-1, 205 kg ha-1 and 37% respectively. The palisadegrass produced on average 1.9 t of dry mass, absorbing a maximum of 6 kg ha-1 or 5.5% of N fertilizer during corn growing. Furthermore, the palisadegrass did not affect N fertilizer distribution in soil-plant system, in which 28.2% was recovered in the soil and 40.4% in the plants (corn + palisadegrass). The results show that for the three intercropping implantation methods the palisadegrass did not compete with corn for N fertilizer.
Descritores: Solo/química
Produtos Agrícolas/crescimento & desenvolvimento
Zea mays/crescimento & desenvolvimento
Fertilizantes
-Estações do Ano
Distribuição Aleatória
Biomassa
Responsável: BR1.1 - BIREME


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Id: biblio-886887
Autor: FERNANDES, FRANCISCO S; GODOY, WESLEY A C; RAMALHO, FRANCISCO S; GARCIA, ADRIANO G; SANTOS, BÁRBARA D B; MALAQUIAS, JOSÉ B.
Título: Population dynamics of Aphis gossypii Glover and in sole and intercropping systems of cotton and cowpea
Fonte: An. acad. bras. ciênc;90(1):311-323, Mar. 2018. tab, graf.
Idioma: en.
Resumo: ABSTRACT Population dynamics of aphids have been studied in sole and intercropping systems. These studies have required the use of more precise analytical tools in order to better understand patterns in quantitative data. Mathematical models are among the most important tools to explain the dynamics of insect populations. This study investigated the population dynamics of aphids Aphis gossypii and Aphis craccivora over time, using mathematical models composed of a set of differential equations as a helpful analytical tool to understand the population dynamics of aphids in arrangements of cotton and cowpea. The treatments were sole cotton, sole cowpea, and three arrangements of cotton intercropped with cowpea (t1, t2 and t3). The plants were infested with two aphid species and were evaluated at 7, 14, 28, 35, 42, and 49 days after the infestations. Mathematical models were used to fit the population dynamics of two aphid species. There were good fits for aphid dynamics by mathematical model over time. The highest population peak of both species A. gossypii and A. craccivora was found in the sole crops, and the lowest population peak was found in crop system t2. These results are important for integrated management programs of aphids in cotton and cowpea.
Descritores: Afídeos/fisiologia
Produtos Agrícolas/parasitologia
Gossypium/parasitologia
Vigna/parasitologia
-Valores de Referência
Especificidade da Espécie
Fatores de Tempo
Asas de Animais/fisiologia
Dinâmica Populacional
Densidade Demográfica
Modelos Teóricos
Limites: Animais
Responsável: BR1.1 - BIREME


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Id: biblio-886893
Autor: SHARIFI, PEYMAN; EBADI, ALI AKBAR.
Título: Relationships of rice yield and quality based on genotype by trait (GT) biplot
Fonte: An. acad. bras. ciênc;90(1):343-356, Mar. 2018. tab, graf.
Idioma: en.
Resumo: ABSTRACT An experiment was conducted to examine the influencing characters on rice by using 64 rice genotypes, including four local landraces, four released cultivars and 56 mutant lines (M5) derived from these genotypes, with application of the genotype by trait (GT) biplot methodology. The first two principal components (PC1 and PC2) accounted for 46.6% of total variation in 64 genotypes. The polygon view of GT biplot suggested seven sections for 64 genotypes. The vertex G38 had good amounts of grain yield, panicle length, hundred grain weight, internodes length, plant height and fertility percentage. Generally based on vector view it was demonstrated that the selection of high grain yield would be performed via thousand grain weight, panicle weight and number of filled grain per panicle. These traits should be considered simultaneously as effective selection criteria evolving high yielding rice genotypes because of their large contribution to grain yield. The genotypes G2, G4 and G7 could be considered for the developing of desirable progenies in the selection strategy of rice improvement programs. This study revealed GT biplot can graphically display the interrelationships among traits. In conclusion, it is recommended the use of GGE biplot to identify superior genotypes for simultaneous improvement of several traits.
Descritores: Oryza/genética
Produtos Agrícolas/genética
Característica Quantitativa Herdável
-Oryza/crescimento & desenvolvimento
Variação Genética/genética
Produtos Agrícolas/crescimento & desenvolvimento
Interação Gene-Ambiente
Irã (Geográfico)
Responsável: BR1.1 - BIREME



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