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VARIABILIDAD RACIAL DE MACRORRESTOS ARQUEOLóGICOS DE ZEA MAYS (POACEAE) Y SUS RELACIONES CON EL PROCESO AGROPASTORIL EN LA PUNA MERIDIONAL ARGENTINA (ANTOFAGASTA DE LA SIERRA, CATAMARCA)
Nurit Oliszewski,Daniel E. Olivera
Darwiniana , 2009,
Abstract: En el presente trabajo se analiza la variabilidad racial de Zea mays y sus implicancias en relación con el establecimiento de un mayor énfasis en las prácticas agrícolas en la Puna meridional argentina para el lapso ca. 1300-700 a os AP, a partir del registro arqueobotánico de los sitios arqueológicos Cueva Cacao 1A y Bajo del Coypar II (Antofagasta de la Sierra, Catamarca). Se identificó la presencia de ocho razas de maíz: Pisincho, Morocho, Morocho amarillo, Marrón, Harinoso amarillo, Capia, Culli y Chullpi. Esta alta biodiversidad es un claro exponente del proceso de incorporación de múltiples razas de maíz en la región, que habría comenzado hacia fines del Período Formativo en algún momento entre 1300 y 1000 a os AP, intensificándose en momentos posteriores.
Variabilidad racial de macrorrestos arqueológicos de Zea mays (Poaceae) y sus relaciones con el proceso agropastoril en la Puna Meridional Argentina (Antofagasta de la Sierra, Catamarca)
Oliszewski,Nurit; Olivera,Daniel E;
Darwiniana , 2009,
Abstract: this paper analyzes the zea mays racial variability and their relationship with the greater emphasis put on agricultural practices in the southern argentine "puna" during ca. 1300-700 years b p, taking in account the archaeobotanical record of the sites "cueva cacao 1a" and "bajo del coypar ii" ("antofagasta de la sierra", catamarca, argentina). eight maize races were identified: pisincho, morocho, morocho amarillo, marrón, harinoso amarillo, capia, culli and chullpi. this high biodiversity is a clear exponent about the introduction process of multiple maize races in the region. this process would have begun between the end of formative period in any moment among 1300 and 1000 years bp and becoming stronger in later moments.
VARIABILIDAD DEL CRECIMIENTO Y RENDIMIENTO DEL CULTIVO DE MAíZ PARA CHOCLO (Zea mays L.) COMO RESPUESTA A DIFERENCIAS EN LAS PROPIEDADES QUíMICAS DEL SUELO EN LA SABANA DE BOGOTá, COLOMBIA VARIABILITY IN GROWTH AND YIELD OF MAIZE (Zea mays L.) IN RESPONSE TO DIFFERENCES IN SOIL CHEMICAL PROPERTIES IN THE BOGOTá PLATEAU, COLOMBIA  [cached]
Jaiver Danilo Sánchez Torres,Gustavo Adolfo Ligarreto Moreno,Fabio Rodrigo Leiva Barón
Revista Facultad Nacional de Agronomía, Medellín , 2012,
Abstract: Resumen. Se estudió el crecimiento de un cultivo de maíz mediante un red sistemática de 32 puntos donde se recolectaron muestras de suelos para determinar pH, N, Ca, K, Mg, Na, Al, P, Cu, Fe, Mn, Zn y B. Se utilizó el análisis de componentes principales para determinar que variables de suelos incidían sobre el crecimiento y rendimiento del cultivo. Posteriormente con un análisis de conglomerados se agruparon los sitios homogéneos según estas características químicas. En esos mismos puntos, se tomaron muestras del material vegetal a los 35, 59, 91, 115, 146 y 162 días después de siembra (dds) y se realizó el análisis de crecimiento calculando la tasa de crecimiento de cultivo (TCC), tasa de asimilación neta (TAN) e índice de área foliar (IAF), y a los 162 dds se evaluó la cosecha. Se realizó un análisis del crecimiento del cultivo y para cada zona homogénea se elaboraron las curvas de crecimiento. El crecimiento del cultivo presentó estructura espacial y su variabilidad fue explicada por un grupo de variables químicas relacionadas con la fertilidad del suelo. Las diferencias en las TCC se debieron a la variabilidad de las TAN y los IAF entre los sitios durante el desarrollo del cultivo; la TAN fue diferente entre los sitios de mayor y menor fertilidad en las etapas iníciales de desarrollo del cultivo; entre tanto, el IAF fue superior todo el ciclo del cultivo en los sitios más fértiles. Abstract. Corn growth was studied through a systematic network of 32 points where were collected soil samples to determine pH, N, Ca, K, Mg, Na, Al, P, Cu, Fe, Mn, Zn, and B. We used the method of principal components to determine which soil variables had an effect on growth and crop yield. Subsequently homogeneous sites according to chemical characteristics were grouped using cluster analysis. In the same points, samples were taken from the plant material at 35, 59, 91,115, 146 and 162 days after sowing (das), and analysis was performed by calculating the crop growth rate (CGR) net assimilation rate (NAR) and leaf area index (LAI), also at 162 das harvest was evaluated. Analysis of crop growth was performed and for each homogeneous cluster were draw growth curves. Crop growth presented a spatial structure which was explained by a group of chemical variables related to soil fertility. Differences in the CGR were due to the variability of NAR and LAI among homogeneous cluster during the growing season, the NAR was different between the homogeneous zones of high and low fertility in the early stages of crop development; meanwhile, LAI was higher throughout the growing seaso
Extra??o de corantes de milho (Zea mays L.)
Gamarra, Felix Martin Cabajal;Leme, Gisele Costa;Tambourgi, Elias Basile;Bittencourt, Edison;
Ciência e Tecnologia de Alimentos , 2009, DOI: 10.1590/S0101-20612009000100010
Abstract: natural colorants were craftly made and widely used before the discovery of the synthetic colorants. the study and the use of natural colorants have become important again in the last few years due to questions raised by the international health organizations and consumers related to the indiscriminate use of synthetic colorants which were linked to the development of degenerative illnesses and environmental impact. the colorant extracted from purple corn (zea mays l.) was used by the inca civilization to prepare food and to dye textile fibers. in this work, pigments from the anthocyanin group were extracted from purple corn and red corn (zea mays l.) varieties and were later characterized. three extraction methods were used: immersion, lixiviation with some changes, and supercritical extraction (esc). the best method of extraction was lixiviation, which reached 88% (m/m) of performance as a function of the mass of colorant extracted and of the raw materials. also using the modified lixiviation it was possible to concentrate the acylate compounds in 3% as well as to recover 85% of solvent used. a ph indicator was obtained by fixing the anthocyanins on a filter paper based on anthocyanins stabilization. this technique can be utilized in laboratory chemistry lessons.
Toxicidad aguda Oral del extracto acuoso de Zea mays Lin
Gleiby Melchor Orta,Liseth García García,Oriela Pino,Carlos Bulnes Goicochea
RETEL : Revista de Toxicología en Línea , 2006,
Abstract: An experimental study was carried out to assess potential toxic effect of unique oral administration of prefixed dosis (5, 50, 500 and 2000 mg/Kg. of corporal weight) of the acuose extract of Zea mays Lin. To develop the same Acute Oral Toxicity - Fixed Dose Method described for Organization for Economic Cooperation and Development (2001) and rats Sprague Dawley (both sexes) with weight among 180 - 230 g was employees. The results do not show evidences of toxic signs neither death until the dose of 2000 mg/Kg p.c, for that the acuose extract evaluated was classified as: Substance that does not present a considerable risk of toxicity if it is ingested for oral administration.
Efecto del Almacenamiento de Granos de Maíz (Zea mays) sobre la Calidad del Aceite Extraído Effect of Grains of Maize (Zea mays) Storage on the Quality of the Extracted Oil  [cached]
Carlos Hernández,Ysamar Rodríguez,Zulay Ni?o
Información Tecnológica , 2009,
Abstract: Se evaluó el efecto del almacenamiento de granos de maíz amarillo (Zea mays) sobre la calidad del aceite obtenido del mismo. Se determinaron los parámetros de calidad del maíz al momento de la recepción, los índices de acidez, peróxido, y el color del aceite extraído de granos almacenados en un silo de concreto por 0, 30, 60 y 90 días, utilizando los procedimientos descritos en las normas vigentes en Venezuela. Se encontró un efecto adverso significativo (P<0.05) del almacenamiento sobre los índices analizados, causado por la humedad e impurezas del grano recibido, así como una deficiencia de 704 m3 min-1 de aire fresco suministrado al silo, lo cual no favorece un adecuado almacenaje. El grano de maíz almacenado durante 90 días produjo incrementos apreciables en el índice de acidez, índice de peróxido y color del aceite crudo obtenido. The effect of storage time on grains of yellow maize (Zea mays) was evaluated on the quality of the oil obtained. The quality parameters detected at the reception of the maize were: indexes of acidity, peroxide and the color of the oil extracted from grains stored in a concrete silo for 0, 30, 60 and 90 days, using the procedures described in the patterns in Venezuela. Adverse significant effects (P<0.05) of the storage time on the indexes analyzed were found. These were caused by the moisture and impurities of the grains, as well as a deficiency of 704 m3 min-1 of fresh air fed to the silo, which affects storage. The grain of maize stored during 90 day produced increases in the index of acidity, index of peroxide and color of the extracted oil.
Caracteriza o da atividade amilásica do malte de milho (Zea mays L.) = Characterization of amylase activity from maize (Zea mays L.) malt  [cached]
Joana Paula Menezes Biazus,José Carlos Curvelo Santana,Roberto Rodrigues de Souza,Elias Basile Tambourgi
Acta Scientiarum : Technology , 2006,
Abstract: Este trabalho objetivou estudar o processo de germina o e a caracteriza o da atividade bioquímica das amilases do malte de milho (Zea mays L.) para gerar uma fonte de amilase de baixo custo e boa atividade enzimática. A atividade enzimática foi monitorada todos os dias durante a germina o das sementes para se obter a melhor condi o de produ o do malte. Os resultados mostraram que a atividade enzimática nas sementes foi maior no 4o. dia de germina o. A caracteriza o bioquímica mostrou que as amilases do malte apresentam faixa ótima de pH entre 4,3 e 6, com temperaturas ótimas a 50°C e 80oC e os valores de Km e Vmax para hidrólise do amido foram de 7,69.10-2 g/L e 7,69.102g/L.min, respectivamente. This work aimed to study the germination process and characterization of the amylolytic activity of the maize (Zea mays L.) malt aiming to obtain source amylases at lower cost. Enzymatic activity was monitored all days during the seed germination, for obtaining thebest condition of malt production. Results showed that the enzymatic activity from maize seeds was larger in 4° germination day. Enzymes characterization showed that the maize malt amylases have optimal zone of pH between 4.3 and 6, with optimal temperatures of 50°C and 80oC. The Km and Vmax values for starch hydrolysis were 7.69.10-2 g/L and 7.69.102g/L.min, respectively.
Otimiza??o da secagem do malte de Zea mays
Biazus, Joana Paula Menezes;Souza, Roberto Rodrigues de;Curvelo-Santana, José Carlos;Tambourgi, Elias Basile;
Ciência e Tecnologia de Alimentos , 2006, DOI: 10.1590/S0101-20612006000400012
Abstract: in this work, the drying process optimization of maize (zea mays) malt was carried out with the purpose of obtaining a commercial derivate of high value without reducing the enzyme activity present in a and b - and attempting to add value to the maize culture. models of drying curves were used to simulate the drying isotherms. a 22 full factorial planning was made, using time factors (5.18, 6, 8, 10 and 10.8 h) around the drying time to determine the humidity in food and the temperatures (54, 65 and 76 °c) close to the optimal temperature of the enzymes and the enzymatic activity in the malt as a solution. the model which most adjusted to the drying kinetic data was the henderson and henderson model and the average humidity taken from the malt was higher than 40%. the drying process optimization showed that drying should be done in the area which is close to 54 °c and the range of 5.18 at 6 h of processing time. the maize malt obtained has good enzymatic potential, thus it helps to add value to maize culture.
FERTILIZER APPLICATION METHODS AND IRRIGATION LEVELS ON EARLY (Zea mays L.) DEVELOPMENT FORMAS DE APLICA O DO FERTILIZANTE E NíVEIS DE IRRIGA O NO DESENVOLVIMENTO DO MILHO (Zea mays)  [cached]
Jorge Luiz do Nascimento,José Xavier de Almeida Neto
Pesquisa Agropecuária Tropical , 2007, DOI: 10.5216/pat.v25i2.2912
Abstract: Early corn development (Zea mays L.) was evaluated through roots (MR) and tops (MA) dry matter in a low tunnel greenhouse pot experiment, in a 2x2x4 factorial completely randomized design with three replications, comparing the following treatments: two Oxisols (a sandy Latossolo Vermelho Escuro — LE and a clay Latossolo Roxo - LR); two methods of fertilizer application (soil mixed - A1, and furrow planting line - A2), and four irrigation levels (0%, 15%, 30%, and 45% deficit in relation to the evapotranspired water). Significant effects were observed for fertilizer application methods and irrigation levels on MA, with 89,6% higher yield for A2, and MA reduction for increased water stress. There was a significant interaction between soil types and fertilizer application methods on MA, with a larger MA in the LE soil for A1 method, while MA was larger in the LR soil for A2 method. For MR, it was observed a significant effect of soil type and fertilizer application methods, with a larger yield in the LR soil under the A2 form. The findings confirm the importance of adequate soil water supply for nutrient absorption processes, resulting in better plant development. The localized fertilizer application is recommended for Oxisols with higher clay contents and larger phosphorus fixation capacity. KEY-WORDS: Fertilizer; irrigation levels; Zea mays. O desenvolvimento inicial da cultura do milho (Zea mays L.) foi avaliado através da produ o de matéria seca das raízes (MR) e da parte aérea (MA) em um experimento conduzido em vasos, abrigado sob uma estufa do tipo túnel baixo. O delineamento experimental foi o inteiramente casualizado, num esquema fatorial 2 x 2 x 4, com os seguintes tratamentos: dois tipos de solo (Latossolo Vermelho Escuro, textura arenosa - LE e Latossolo Roxo, textura argilosa - LR); duas formas de aplica o do adubo (misturado ao solo - A1, e localizado no sulco de plantio - A2); e quatro níveis de irriga o (0%, 15%, 30% e 45% de déficit em rela o à água evapotranspirada), com três repeti es. Houve um efeito significativo da forma de aplica o do adubo e dos níveis de irriga o sobre a MA, com uma produ o 89,6% maior para a forma A2 de aplica o do adubo, bem como uma redu o da MA em fun o do aumento do estresse hídrico. Verificou-se uma intera o significativa entre os fatores solo e forma de aplica o do adubo sobre a MA, com uma MA maior no LE para a forma A1, enquanto a MA foi maior no LR para a forma A2. Quanto à MR, houve efeito significativo do tipo de solo e forma de aplica o do adubo com uma maior produ o no LR e na forma A2.
Evaluación de variedades e híbridos de maíz (zea mays l.) para ensilado  [cached]
Jesus Fuentes,Antonio Cruz,lorenzo Castro,Gilberto Gloria
Agronomía Mesoamericana , 2001,
Abstract: Evaluación de variedades e híbridos de maíz (Zea mays) para ensilado. Se realizó un experimento con el fin de evaluar el comportamiento de 16 variedades de maíz (Zea mays L.) cultivadas para forraje y ensiladas después del corte. Las pruebas de dicha evaluación consistieron en: la determinación de la producción de forraje por hectárea en base a materia verde y a materia seca; contenido de proteína y digestibilidad in vitro de la materia seca (DIVMS) y materia orgánica DIVMO. Se utilizó un dise o completamente al azar y prueba de Tukey para comprobación de medias. Las unidades más sobresalientes en cuánto a producción de forraje en base a materia verde fueron la AN-446 con 114028 kg/ha, la AN-445 con 110993 kg/ha y la AN-430 R con 106389 kg/ha. En relación a la producción de materia seca las unidades más sobresalientes fueron la AN-447 con 29270 kg/ha, la AN-461 con 28026 kg/ha y la VS-373 con 25434 kg/ha. Las variedades con mayor contenido de proteína (%) fueron la G-4657 con 7,58, la AN-388 con 7,28 y la AN-448 con 7,17. Los mejores coeficientes (%) de DIVMS fueron para las unidades G- 1990 (69,14), AN-446 (3,78) y AN-430RR (63,50), mientras que para los coeficientes de DIVMO fueron las unidades G- 1990 (71,78), AN-446 (65,20) y AN-447 (65,2). Las variedades AN-446 y AN-447 aparecen repetidamente en varios de los parámetros evaluados entre los más sobresalientes, sin embargo es necesario realizar nuevos estudios que permitan comprobar este comportamiento
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