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Search Results: 1 - 10 of 30009 matches for " Alana das Chagas Ferreira Aguiar "
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Crescimento e produtividade de duas cultivares de milho de alta qualidade protéica em solo de baixa fertilidade
Aguiar, Alana das Chagas Ferreira;Moura, Emanoel Gomes de;
Bragantia , 2003, DOI: 10.1590/S0006-87052003000300009
Abstract: maize cultivars with protein of high biological value (qpm) developed by embrapa would be a good alternative for the brazilian low income farmers, but in the humid tropic their performances should be confirmed under local prevalent field conditions. a field experiment was done in january, 1999, in an argisol and under the system of alley cropping, with plots of 4 x 6 m2 and four replications, to evaluate the growth and productivity of two high quality protein maize cultivars (br 473 and br 2121) in comparison to three other related cultivars used in the farming system of maranhao state: ferro (traditional cultivar, collected with local farmers), br 106 and ag 1051 (low and medium technological level respectively). the leaf rate index, net assimilation rate, the number of cob, grain yield per cob, cob and 100 grains weight, and harvest index were evaluated. the results showed that cultivar br 473 can be recommended to be cultivated in chemically stressed soil and high temperature conditions. the cultivar ag 1051 presented higher grain yield. the general use of local traditional cultivar ferro by low income farmers can only be justified by the possibility of field storage, since its productivity was less than all other cultivars tested.
Crescimento e produtividade de duas cultivares de milho de alta qualidade protéica em solo de baixa fertilidade
Aguiar Alana das Chagas Ferreira,Moura Emanoel Gomes de
Bragantia , 2003,
Abstract: As cultivares de milho com proteína de alto valor biológico (QPM), lan adas pela EMBRAPA, podem-se constituir em boa alternativa para a agricultura familiar brasileira. No trópico úmido seu desempenho dever ser confirmado nas condi es prevalentes entre os agricultores. Diante disso, foi instalado, em janeiro de 1999, em Argissolo Vermelho-Amarelo Distrófico arênico e sob sistema de cultivo em aléias, um experimento em blocos ao acaso, com parcelas de 4 x 6 m2 e quatro repeti es, para avaliar o crescimento e a produtividade de duas cultivares de milho de alto valor protéico (BR 473 e BR 2121), em compara o com outras três utilizadas na agricultura maranhense: Ferro (cultivar tradicional, recolhida junto aos agricultores), BR 106 e AG 1051 (de baixo e médio nível tecnológico respectivamente). Foram avaliados o índice de área foliar, a taxa de assimila o líquida, o número de espigas, gr os por espiga, massa da espiga e de 100 gr os e o índice de colheita. Concluiu-se que a cultivar BR 473 pode ser recomendada para condi es de solos ácidos de baixa fertilidade e para temperaturas altas, exceto BR 2121. A cultivar AG 1051 apresentou produtividade muito superior em rela o às demais cultivares. O uso generalizado da cultivar Ferro pela agricultura familiar só se justifica pela possibilidade de armazenamento na lavoura, que consiste em deixar o milho no campo, vários meses após a matura o, pela sua alta resistência às pragas de pós-colheita; ademais sua produtividade foi menor que todas as outras cultivares testadas.
Environmental and agricultural benefits of a management system designed for sandy loam soils of the humid tropics
Aguiar, Alana das Chagas Ferreira;Amorim, Andreia Pereira;Coêlho, Katia Pereira;Moura, Emanoel Gomes de;
Revista Brasileira de Ciência do Solo , 2009, DOI: 10.1590/S0100-06832009000500037
Abstract: a sustainable management of soils with low natural fertility on family farms in the humid tropics is a great challenge and overcoming it would be an enormous benefit for the environment and the farmers. the objective of this study was to assess the environmental and agronomic benefits of alley cropping, based on the evaluation of c sequestration, soil quality indicators, and corn yields. combinations of four legumes were used in alley cropping systems in the following treatments: clitoria fairchildiana + cajanus cajan; acacia mangium + cajanus cajan; leucaena leucocephala + cajanus cajan; clitoria fairchildiana + leucaena leucocephala; leucaena leucocephala + acacia mangium and a control. corn was used as a cash crop. the c content was determined in the different compartments of soil organic matter, cec, available p, base saturation, percentage of water saturation, the period of the root hospitality factor below the critical level and corn yield. it was concluded that alley cropping could substitute the slash and burn system in the humid tropics. the main environmental benefit of alley cropping is the maintenance of a dynamic equilibrium between c input and output that could sustain up to 10 mg ha-1 of c in the litter layer, decreasing atmospheric co2 levels. alley cropping is also beneficial from the agricultural point of view, because it increases base saturation and decreases physical resistance to root penetration in the soil layer 0 - 10 cm, which ensures the increase and sustainability of corn yield.
Growth and productivity of corn as affected by mulching and tillage in Alley cropping systems
Moura, Emanoel Gomes de;Albuquerque, Jonas Mendes;Aguiar, Alana das Chagas Ferreira;
Scientia Agricola , 2008, DOI: 10.1590/S0103-90162008000200014
Abstract: alley cropping has been considered a means of intensifying land use sustainably as an alternative to slash and burn agriculture in tropical regions. an experimental trial was used to evaluating the growth and productivity of corn under alley cropping to test the viability of this system as a sustainable land use practice in an amazonian ultisol. the experimental layout was a completely randomized block design with four replications of six treatments: mulch with 13.4 and 8.9 t ha-1 of pigeon pea, and a control treatment without mulch of pigeon pea, with or without tillage. sustainability of soil and crop were determined from changes on physical properties, such as total porosity, air capacity, available water capacity of the soil, net assimilation rate, crop growth rate, and leaf area index, as well as several productivity parameters, including average weight of ears, weight of 100 grains, and total dry matter. both mulching and tillage increased the air capacity. mulching of tilled areas protects the soil against the rainfall impact and prevented its recompaction. the reduced air capacity of the soil had a negative impact on the net assimilation rate, resulting in lower productivity in the no-mulch and no-till plots, mainly due to the reduction of grain weight.
Avalia??o de um sistema de cultivo em aléias em um argissolo franco-arenoso da regi?o amaz?nica
Moura, Emanoel Gomes de;Silva, Ant?nio José de Fran?a;Furtado, Mariléia Barros;Aguiar, Alana das Chagas Ferreira;
Revista Brasileira de Ciência do Solo , 2008, DOI: 10.1590/S0100-06832008000400038
Abstract: in the humid tropics the buildup and maintenance of soil fertility are major challenges in terms of sustainability of agroecosystems. the objective of this study was to evaluate an alley cropping system with pigeon pea (cajanus cajan) on an alfisol, with annual application of lime and potassium, with special concern regarding the viability of this system as an alternative to slash and burn practiced in tropical agriculture. pigeon pea and maize (zea mays) were planted in the experiment with the following treatments: t = control, with bare soil; g2, g2.5 and g3 = treatments with pigeon pea, spacing between lines of 2, 2.5 and 3 m, respectively; g2k, g2.5k and g3k = pigeon pea, same spacing, plus potassium; g2c, g2.5c and g3c = pigeon pea, same spacing, plus liming; g2kc, g2.5kc and g3kc = pigeon pea, same spacing, plus potassium and liming. mulch and nutrient balance affected maize yield most in the alley cropping system and must therefore be considered fundamental for the sustainable management of sandy-loamy alfisols in the humid tropics.
Chemical and physical fertility indicators of a weakly-structured Ultisol after liming and mulching
Moura, Emanoel Gomes de;Coelho, Kátia Pereira;Freitas, Idelfonso Colares de;Aguiar, Alana das Chagas Ferreira;
Scientia Agricola , 2009, DOI: 10.1590/S0103-90162009000600012
Abstract: in the humid tropic, chemical and physical soil properties that decrease soil's nutrient availability and increase oxygen deficiency are important as restrictions to crop growth. the objective of this study was to evaluate the relations between plant growth and chemical and physical fertility indicators of an ultisol developed from sediments of the itapecuru formation in central-northern state of maranh?o, brazil. an experiment was established with randomized block design, four replicates, and six treatments: 6.0 mg ha-1 mulch with or without liming; 3.0 mg ha-1 mulch with or without liming; bare soil with or without liming. determinations in the plants included leaf area index, net assimilation rate, and the yield parameters: mean number and weight of ears, 100-kernel weight, harvest index, and total grain yield. soil determinations consisted of bulk density variations on the surface and at 20 cm, effective porosity evolution after intentional flooding, and alterations in chemical indicators such as cation exchange capacity, bases saturation, organic carbon, and macronutrient contents. mulching and liming were equivalent with regard to their influence on leaf area yield, but mulching was more important for corn productivity because of its greater effect on net photosynthesis.
Soil Management and Efficiency of Rhizobia Strains of Cowpea Vigna unguiculata (L.) Walp. in the Tropics Manejo de Suelo y Eficiencia de Cepas de Rizobio de Frijol Vigna unguiculata (L.) Walp. en los Trópicos
José Geraldo Donizetti dos Santos,Alana das Chagas Ferreira Aguiar,Edilson Máximo Silva Junior,Danubia Lemes Dadalto
Chilean Journal of Agricultural Research , 2011,
Abstract: In the humid tropics, the largest obstacle to the implementation of sustainable farming systems is the reduced efficiency of nutrient use by crops. This study assesses the effectiveness of five selected rhizobia strains in symbiosis with cowpea (Vigna unguiculata (L.) Walp.), with the objective of replacing N fertilization in the predominant agricultural system used by smallholder farmers. The study was carried out in three adjacent areas with distinct agricultural uses: conventional tillage, itinerant agriculture, and a no-till system. The experimental design was in randomized complete blocks with four replicates and seven treatments: five rhizobia strains (BR3262, BR3267, BR3299, INPA3-11B, and UFLA 3-84) and two controls without inoculation (one without mineral N and another fertilized with 74 kg N ha-1). We measured the dry mass of 100 grains, nodules and shoots, as well as cowpea yields and calculated relative and absolute efficiency indices for dry biomass production of cowpea shoots. Agricultural uses affected the number and dry mass of the nodules and, consequently, the mass of the dry plant matter and bean yield. In terms of yield, there was a major difference between the conventional and the itinerant systems. Yield was around four times as high in the itinerant system (1009.9 kg ha-1 compared to 243.7 kg ha-1). Under conditions of cohesion-prone soils, the system of conventional tillage reduces the possibility of cultivation of a second harvest in the year even with inoculation or N fertilization. En los trópicos húmedos, el mayor obstáculo para la aplicación de sistemas de agricultura sostenible es la reducción de la eficiencia del uso de nutrientes por los cultivos. Este estudio evalúa la eficacia de cinco cepas de rizobios seleccionados en simbiosis con frijol (Vigna unguiculata (L.) Walp.), con el objetivo de sustituir la fertilización nitrogenada en el sistema de uso de suelo predominante utilizado por los peque os agricultores. El estudio se llevó a cabo en tres zonas adyacentes de distintos usos agrícolas: labranza convencional, agricultura itinerante, y un sistema de no laboreo. El dise o experimental fue en bloques al azar con cuatro repeticiones y siete tratamientos: cinco cepas de rizobios (BR3262, BR3267, BR3299, INPA3-11B y UFLA 3-84) y dos controles sin inocular (uno sin N mineral y otro fertilizado con 74 kg de N ha-1). Se midió el peso en seco de 100 granos, de los nódulos y de los brotes, así como los rendimientos de frijol y se calcularon los índices de eficiencia relativa y absoluta para la producción de biomasa seca de los
Comportamento de dois genótipos de milho cultivados em sistema de aléias preestabelecido com diferentes leguminosas arbóreas
Leite, Andréia Araújo Lima;Ferraz Junior, Altamiro Souza de Lima;Moura, Emanoel Gomes de;Aguiar, Alana das Chagas Ferreira;
Bragantia , 2008, DOI: 10.1590/S0006-87052008000400009
Abstract: alley cropping has been recommended as alternative land use to slash-and-burn agriculture in humid tropics. however, interespecific competition between cash crop and hedgerow can reduce this potential. this study aimed to evaluate the feasibility of maize crop in a leguminous tree alley cropping. a random block experimental design was adopted, with four replicates and five treatments: alleys of "sombreiro" (clitoria fairchildiana), inga (inga edulis), pigeon pea (cajanus cajan), and leucaena (leucaena leucocephala) and a control treatment without alley. c and n partitioning, grain yield, 1000 grain mass and interspecifics competition between maize varieties and legume hedgerows were evaluated. grain yield was higher for c. fairchildiana and l. leucocephala treatments. the grain yield of hibrid maize was higher than that of maize variety at all treatments. the grain yield and 1000 grain mass maize was not affected by distance of legume hedgerows. this study concluded that the alley cropping with leguminous tree is an important alternative to the sustainable management of agroecosystems in humid tropics. furthermore, in this region, the productivity of maize grain is favored in alley cropping with leguminous trees, like sombreiro, inga and leucena by genotypes efficient in the use of nitrogen, whose timing between its release and absorption when applied by means of pulses, must be enhanced.
Soil Management and Efficiency of Rhizobia Strains of Cowpea Vigna unguiculata (L.) Walp. in the Tropics
Donizetti dos Santos,José Geraldo; Ferreira Aguiar,Alana das Chagas; Silva Junior,Edilson Máximo; Lemes Dadalto,Danubia; Rodrigues Sousa,Merijane; Ribeiro Xavier,Gustavo; Gomes de Moura,Emanoel;
Chilean journal of agricultural research , 2011, DOI: 10.4067/S0718-58392011000400015
Abstract: in the humid tropics, the largest obstacle to the implementation of sustainable farming systems is the reduced efficiency of nutrient use by crops. this study assesses the effectiveness of five selected rhizobia strains in symbiosis with cowpea (vigna unguiculata (l.) walp.), with the objective of replacing n fertilization in the predominant agricultural system used by smallholder farmers. the study was carried out in three adjacent areas with distinct agricultural uses: conventional tillage, itinerant agriculture, and a no-till system. the experimental design was in randomized complete blocks with four replicates and seven treatments: five rhizobia strains (br3262, br3267, br3299, inpa3-11b, and ufla 3-84) and two controls without inoculation (one without mineral n and another fertilized with 74 kg n ha-1). we measured the dry mass of 100 grains, nodules and shoots, as well as cowpea yields and calculated relative and absolute efficiency indices for dry biomass production of cowpea shoots. agricultural uses affected the number and dry mass of the nodules and, consequently, the mass of the dry plant matter and bean yield. in terms of yield, there was a major difference between the conventional and the itinerant systems. yield was around four times as high in the itinerant system (1009.9 kg ha-1 compared to 243.7 kg ha-1). under conditions of cohesion-prone soils, the system of conventional tillage reduces the possibility of cultivation of a second harvest in the year even with inoculation or n fertilization.
Soluble and Insoluble Fiber in Some Amazonian Fruits with Low Energy Density  [PDF]
Jaime Paiva Lopes Aguiar, Francisca das Chagas do Amaral Souza
Food and Nutrition Sciences (FNS) , 2014, DOI: 10.4236/fns.2014.514154
Abstract:

Fruits are unarguably one of the main sources of dietary fiber, but are regional Amazonian fruits sources of dietary fiber? The objective of the present study was to assess the nutritional characteristics and fiber contents of fresh fruits with low energy density. The study fruits wereabiu, bacuri, carambola, ingá-cipó, mapati, and taperebá acquired from the National Institute for Amazonian Research (INPA) and collected along kilometers 08 and 60 of highway BR174, AM-Brasil. Ash, protein, lipid, carbohydrate, energy and fiber contents were determined three times. The six fruits have very small and significantly different protein contents (p < 0.05). Taperebá and mapati presented the highest (4.65 g) and lowest (0.84 g) fiber contents, respectively. Except for abiu (0.49 g), the low lipid contents of the study fruits confirmed their low energy density. The soluble fiber content of the fruits was generally low, being highest in taperebá (1.51 g). The insoluble fiber fraction prevailed in all six study fruits, with taperebá and mapati presenting the highest (3.14 g) and lowest (0.65 g) insoluble fiber contents, respectively. The dietary fiber contents show that the study fruits can contribute to the composition of diets with appropriate dietary fiber contents and low energy densities.

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