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Cubiertas Vegetales en Producción Orgánica de Frambuesa: Efectos sobre el Contenido de Nutrientes del Suelo y en el Crecimiento y Producción de las Plantas Cover Crops in Organic Raspberry Production: Effects on Soil Nutrient Content, and Raspberry Growth and Yield
Carlos Ovalle M,María Inés González A,Alejandro del Pozo L,Juan Hirzel C
Agricultura Técnica , 2007,
Abstract: Se realizó un estudio de evaluación y selección de cubiertas vegetales para mejora el manejo de suelos entre las hileras de un huerto orgánico de frambuesa (Rubus idaeus L.). Las cubiertas evaluadas fueron: mezcla de trébol subterráneo (Trifolium subterraneum L.) con trébol balansa (T. michelianum Savi), lotera (Lotus corniculatus L.), trébol blanco (T. repens L.), festuca (Festuca arundinacea Schreb.), mezcla de trébol blanco y festuca, y un testigo sin cubierta vegetal. El ensayo se realizó en Chillán, Chile (36°37’ lat. Sur, 72°00’ long. Oeste), durante dos temporadas. El dise o experimental fue de bloques al azar con cuatro repeticiones. La distancia de plantación entre hileras de frambuesa fue de >3 m y cada parcela experimental tenía una superficie de 60 m2. Las cubiertas que incluyeron trébol blanco solo o en mezcla con festuca presentaron la mayor densidad de plantas (828 y 1788 plantas m-2 en el segundo a o, respectivamente), producción de biomasa (9,3 and10,4 t MS ha-1 a o-1 en el segundo a o, respectivamente) y contribución específica de las especies sembradas (sobre 90 % de contribución de las especies sembradas). La mezcla de especies anuales no tuvo un buen comportamiento, particularmente durante la segunda temporada. Se encontró un claro efecto de las cubiertas sobre el contenido de N y K del suelo; sin embargo, no modificaron el contenido de materia orgánica ni pH del suelo. Las cubiertas que controlaron en mejor forma el crecimiento de las malezas fueron aquellas que incluían festuca y/o trébol blanco A study of the evaluation and selection of cover crops to improve soil management in an organic orchard of raspberry (Rubus idaeus L.) was carried out. The evaluated cover crops were: a mixture of subterranean clover (Trifolium subterraneum L.) and balansa clover (T. michelianum Savi), birdsfoot trefoil (Lotus corniculatus L.), white clover (T. repens L.), fescue (Festuca arundinacea Schreb.), a mixture of white clover and fescue, and a control without vegetation. The trial was conducted in Chillán, Chile (36°37’ S, 72°00’ W), during two seasons. The experimental design was randomized blocks with four replicates. Planting distance between raspberry rows was 3 m, and each experimental plot was 60 m2. Covers that included white clover as a single species and white clover in mixture with tall fescue had the highest plant density (828 and 1788 plant m-2, in the second year, respectively), biomass (9.3 and 10.4 t DM ha-1 yr-1, in the second year, respectively) and specific contribution of the sown species (more than 90% contribution of sown spe
Cubiertas Vegetales en Producción Orgánica de Frambuesa: Efectos sobre el Contenido de Nutrientes del Suelo y en el Crecimiento y Producción de las Plantas
Ovalle M,Carlos; González A,María Inés; del Pozo L,Alejandro; Hirzel C,Juan; Hernaiz,Viviana;
Agricultura Técnica , 2007, DOI: 10.4067/S0365-28072007000300006
Abstract: a study of the evaluation and selection of cover crops to improve soil management in an organic orchard of raspberry (rubus idaeus l.) was carried out. the evaluated cover crops were: a mixture of subterranean clover (trifolium subterraneum l.) and balansa clover (t. michelianum savi), birdsfoot trefoil (lotus corniculatus l.), white clover (t. repens l.), fescue (festuca arundinacea schreb.), a mixture of white clover and fescue, and a control without vegetation. the trial was conducted in chillán, chile (36°37? s, 72°00? w), during two seasons. the experimental design was randomized blocks with four replicates. planting distance between raspberry rows was 3 m, and each experimental plot was 60 m2. covers that included white clover as a single species and white clover in mixture with tall fescue had the highest plant density (828 and 1788 plant m-2, in the second year, respectively), biomass (9.3 and 10.4 t dm ha-1 yr-1, in the second year, respectively) and specific contribution of the sown species (more than 90% contribution of sown species). mixture of annual species did not have a good performance, particularly during the second season. a clear effect of the covers on soil content of nitrogen (n) and potassium (k) was found; however, soil organic matter content and ph were not affected. weed growth was best controlled by the cover crops that included fescue and/or white clover.
Cubiertas Vegetales en Vi?edos: Comportamiento de mezclas de Leguminosas Forrajeras Anuales y Efectos sobre la Fertilidad del Suelo
Ovalle,Carlos; del Pozo,Alejandro; Lavín,Arturo; Hirzel,Juan;
Agricultura Técnica , 2007, DOI: 10.4067/S0365-28072007000400006
Abstract: with the objective of evaluating and selecting cover crops to improve soil management in vineyards (vitis vinifera l.) cv. cabernet sauvignon, five cover pastures were evaluated: a) control without vegetation; b) control with spontaneous vegetation; c) legume mixture of early maturing cultivars of subterranean clover (trifolium subterraneum l.) and burr medic (medicago polymorpha l.); d) legumes mixture of late maturing cultivars of subterranean clover and balansa clover (t. michelianumsavi); and e) legumes mixture of late maturing cultivars and annual ryegrass (lolium rigidum gaud.). the study was conducted at cauquenes experimental center, agriculture research institute (inia), over two seasons, 2005-2006 and 2006-2007. the experimental design was randomized blocks with four replicates. the three pasture mixtures had a good establishment and achieved high populations. biomass production was significantly higher (p ≤ 0.05) in the mixtures with late maturing cultivars of subterranean clover and balansa clover, compared to the mixture of early maturing cultivars of subterranean clover and burr medic (2.3 to 4 t dm ha-1 yr -1 and 5.3 to 6.2 t dm ha-1 yr -1 in the first and second year, respectively). the contents of n, p and k in the biomass of the cover crops were higher (p ≤ 0.05) than those covers with spontaneous species, which allowed for increasing the content of available n in the soil. as well, higher contents of k and p were detected in the soil. the over crops exercised an important detrimental effect on the population of the spontaneous species that grow in the inter-rows of the vineyard.
Cubiertas Vegetales en Vi edos: Comportamiento de mezclas de Leguminosas Forrajeras Anuales y Efectos sobre la Fertilidad del Suelo Cover Crops in Vineyards: Performance of Annual Forage Legume Mixtures and Effects on Soil Fertility
Carlos Ovalle,Alejandro del Pozo,Arturo Lavín,Juan Hirzel
Agricultura Técnica , 2007,
Abstract: Con el objetivo de evaluar y seleccionar cubiertas vegetales como cultivos entre hileras, para mejorar el manejo del suelo en un vi edo (Vitis vinifera L.) cv. Cabernet Sauvignon, se evaluaron cinco cubiertas: a) testigo sin vegetación; b) testigo con vegetación espontánea; c) mezcla de leguminosas de cultivares precoces de trébol subterráneo (Trifolium subterraneum L.) con hualputra (Medicago polymorpha L.); d) mezcla de cultivares tardíos de trébol subterráneo con trébol balansa (T. michelianum Savi); e) mezcla de leguminosas tardías con ballica anual (Lolium rigidum Gaud .) El ensayo se realizó en el Centro Experimental Cauquenes del Instituto de Investigaciones Agropecuarias (INIA), durante dos temporadas, 2005-2006 y 2006-2007. El dise o experimental fue bloques al azar con cuatro repeticiones. Las tres mezclas forrajeras se establecieron adecuadamente y lograron altas poblaciones. La producción de biomasa fue significativamente más alta (P ≤ 0,05) en las mezclas de tréboles tardíos y trébol balansa, respecto de la mezcla de tréboles subterráneos precoces y hualputra (2,3 y 4 t MS ha-1 a o-1 y 5,3 y 6,2 t MS ha-1 a o -1 en el primer y segundo a o, respectivamente). Los contenidos de N, P y K en la biomasa de las cubiertas fueron mayores que en las cubiertas de especies espontáneas, lo que incrementó el contenido de N disponible en el suelo. Se encontró un mayor contenido de K y P en el suelo. Las cubiertas ejercieron un efecto detrimental sobre la población de las especies espontáneas o malezas que crecen en la entre hilera del vi edo. With the objective of evaluating and selecting cover crops to improve soil management in vineyards (Vitis vinifera L.) cv. Cabernet Sauvignon, five cover pastures were evaluated: a) control without vegetation; b) control with spontaneous vegetation; c) legume mixture of early maturing cultivars of subterranean clover (Trifolium subterraneum L.) and burr medic (Medicago polymorpha L.); d) legumes mixture of late maturing cultivars of subterranean clover and balansa clover (T. michelianumSavi); and e) legumes mixture of late maturing cultivars and annual ryegrass (Lolium rigidum Gaud.). The study was conducted at Cauquenes Experimental Center, Agriculture Research Institute (INIA), over two seasons, 2005-2006 and 2006-2007. The experimental design was randomized blocks with four replicates. The three pasture mixtures had a good establishment and achieved high populations. Biomass production was significantly higher (P ≤ 0.05) in the mixtures with late maturing cultivars of subterranean clover and balansa clover, compar
Pig Compost Use on Zinc and Copper Concentrations in Soils and Corn Plants  [PDF]
Juan Hirzel, Ingrid Walter
American Journal of Plant Sciences (AJPS) , 2015, DOI: 10.4236/ajps.2015.64057
Abstract: The use of pig compost (PC) in agricultural land has increased in Chile in the last years. This organic amendment is a valuable nutritional source for crops, but its applying must be done in a controlled manner since it exhibited high copper (Cu) and zinc (Zn) concentrations. A short-term field experiment was conducted out to study the effects of increasing PC rates on the production and quality corn crop in two soils located at south central Chile. Five treatments were evaluated: control without fertilization (C), conventional fertilization (CF) (350 kg N ha-1), and three increasing PC rates (15.33, 30.65, and 61.31 Mg·ha-1, corresponding to 350, 700, and 1400 kg N ha-1, respectively) in a split plot design with four replicates. The overall results indicated that dry matter production, grain yield, and plant Zn and Cu concentrations were similar among fertilization sources and rates. Extractable soil Zn concentration exhibited a rate-related increase of PC in both locations, while Cu concentration exhibited this behavior only at the soil located in Chillan. Nevertheless, the values obtained were below of those considered phytotoxic levels. Therefore, the contribution of Zn and Cu through PC applying at different rates to the soils studied showed a slight affect in soil extractable Zn and Cu values without negatively effects on quantity and quality corn crop. The organic amendment applied can be a good and cheaper substitute to conventional fertilization, although further monitoring of Zn and Cu soil levels should be carried out to avoid any environmental risk.
Determinación de la producción de materia seca y extracción de nitrógeno, fósforo, potasio, calcio y magnesio en Liatris callilepis
Hirzel C.,Juan; Ruz J.,Emilio; Schiappacasse,Flavia;
Agricultura Técnica , 2003, DOI: 10.4067/S0365-28072003000200008
Abstract: commercial flower production in chile has become important in the last few years. production technology associated to this area is still in development. in order to learn about biomass production and n, p, k ,ca, and mg accumulation during the growing cycle of liatris callilepis (l.) willd, a study was conducted under production conditions, in an andisol diguillin series (typic melanoxerands). in this study flower production and flower quality were evaluated, as well as nutrient extraction of whole plants including aerial part and roots (crown) were evaluated under conditions of none, medium and high fertilization. production evaluation was performed at different phenological stages: planting (day 0), stem appearance (day 21), spike development (day 45), spike coloration (day 67), stem harvest (day 71), crown harvest (day 160). flower quality evaluation was done at the time of stem harvest. the results obtained indicated that l. callilepis had a sigmoid curve of development, and no significant differences were found in production under the three different fertilization conditions. biomass production of the treatment without fertilization was 21.7 t ha-1, with an absorption rate per hectare of 266 kg n, 32 kg p, 345 kg k, 180 kg ca, and 91 kg mg. quality of floral stem was not affected by fertilization. biomass production at the harvest of crowns responded to treatment with higher fertilization doses.
EVALUACIóN DE LA RECOMENDACIóN DE FERTILIZACIóN NITROGENADA PARA CULTIVOS ANUALES EN SUELOS DE ORIGEN VOLCáNICO USANDO UN MODELO DE SIMULACIóN
Erick,Zagal V.; Hirzel C.,Juan; Vidal P.,Iván;
Agricultura Técnica , 2003, DOI: 10.4067/S0365-28072003000100012
Abstract: fertilizer recommendation systems used to optimize nitrogen fertilization can be divided into three groups: systems based principally on soil analysis, systems based on plant analysis, and systems based on simulation models. one of the available models that describes n flows in plant and soil systems applicable to agricultural ecosystems is the "rothamsted model" (rothamsted nitrogen turnover model). this experiment used the sundial model, a pc-based version of the rothamsted model, to evaluate n-fertilization recommendations made by the technological transfer groups (gtts) of mulchén (37o42? s lat and 72o14? w long) and of el carmen (36o51? s lat and 72o01? w long), considering the respective agricultural management systems. nitrate leaching estimates were also determined for normal rainfall conditions. the results obtained indicate that the sundial model is sensitive to the agricultural management performed in foothill conditions for the crop rotations considered. nitrogen dose rates and fertilization strategy used by the farmers coincide to those calculated by the model, showing acceptable yields and moderate nitrogen losses. the usefulness of the sundial computational model as a tool to generate nitrogen fertilization recommendations is discussed.
EVALUACIóN DE LA RECOMENDACIóN DE FERTILIZACIóN NITROGENADA PARA CULTIVOS ANUALES EN SUELOS DE ORIGEN VOLCáNICO USANDO UN MODELO DE SIMULACIóN Evaluation of nitrogen-fertilizer recommendation for annual crops in soils of volcanic origin using a simulation model
Zagal V. Erick,Juan Hirzel C.,Iván Vidal P.
Agricultura Técnica , 2003,
Abstract: Los sistemas de recomendaciones para optimizar la fertilización nitrogenada se pueden dividir en tres grupos: sistemas basados principalmente en análisis de suelos, sistemas basados en análisis de plantas, y sistemas basados en modelos de simulación. Dentro de los modelos existentes que describen el flujo de N en un sistema planta y suelo aplicables a ecosistemas agrícolas, se encuentra el modelo Rothamsted (Rothamsted Nitrogen Turnover Model). En este trabajo se utilizó el modelo SUNDIAL, versión computacional del modelo Rothamsted, para evaluar las recomendaciones de fertilización nitrogenada realizadas por los grupos de transferencia tecnológica (GTTs) de las localidades de Mulchén (37°42’ lat. Sur y 72°14’ long. Oeste) y el Carmen (36°51’ lat. Sur y 72°01’ long. Oeste), considerando los manejos agronómicos respectivos. Se incluyeron, además, estimaciones de lixiviación de nitratos para las condiciones de pluviometría de la zona. Los resultados obtenidos indican que el modelo SUNDIAL es sensible a los manejos agronómicos realizados en condiciones de precordillera para la rotación de cultivos considerada. Las dosis de N y la estrategia de fertilización nitrogenada usadas por los agricultores en los casos de estudio (Mulchén y El Carmen), coinciden con las calculadas a través del modelo, logrando rendimientos aceptables y pérdidas de N moderadas. Se analiza la utilidad del modelo computacional SUNDIAL como herramienta para generar recomendaciones de fertilización nitrogenada. Fertilizer recommendation systems used to optimize nitrogen fertilization can be divided into three groups: systems based principally on soil analysis, systems based on plant analysis, and systems based on simulation models. One of the available models that describes N flows in plant and soil systems applicable to agricultural ecosystems is the "Rothamsted Model" (Rothamsted Nitrogen Turnover Model). This experiment used the SUNDIAL model, a PC-based version of the Rothamsted Model, to evaluate N-fertilization recommendations made by the technological transfer groups (GTTs) of Mulchén (37o42’ S lat and 72o14’ W long) and of El Carmen (36o51’ S lat and 72o01’ W long), considering the respective agricultural management systems. Nitrate leaching estimates were also determined for normal rainfall conditions. The results obtained indicate that the SUNDIAL model is sensitive to the agricultural management performed in foothill conditions for the crop rotations considered. Nitrogen dose rates and fertilization strategy used by the farmers coincide to those calculated by the model, showin
Precursor B-Cell Acute Lymphoblastic Leukemia/Lymphoma with L3 Morphology, Philadelphia Chromosome, MYC Gene Translocation, and Coexpression of TdT and Surface Light Chains: A Case Report
Alicia C. Hirzel,Aaron Cotrell,Robert Gasparini,Vathany Sriganeshan
Case Reports in Pathology , 2013, DOI: 10.1155/2013/679892
Abstract:
Precursor B-Cell Acute Lymphoblastic Leukemia/Lymphoma with L3 Morphology, Philadelphia Chromosome, MYC Gene Translocation, and Coexpression of TdT and Surface Light Chains: A Case Report
Alicia C. Hirzel,Aaron Cotrell,Robert Gasparini,Vathany Sriganeshan
Case Reports in Pathology , 2013, DOI: 10.1155/2013/679892
Abstract: Acute lymphoblastic leukemia is predominantly found in children. It is a neoplasm of precursor cells or lymphoblasts committed to either a B- or T-cell lineage. The immature cells in B-acute lymphoblastic leukemia/lymphoma can be small or medium sized with scant or moderate cytoplasm and typically express B-cell markers such as CD19, cytoplasmic CD79a, and TdT without surface light chains. These markers, along with cytogenetic studies, are vital to the diagnosis, classification, and treatment of these neoplasms. We present an unusual case of a precursor B-cell ALL, in an 82-year-old woman, who presented with pancytopenia and widespread lymphadenopathy. The cells show L3 morphology (Burkitt-like lymphoma) with coexpression of TdT and surface light chains in addition to an MYC gene translocation and Philadelphia chromosome. 1. Introduction Precursor lymphoid neoplasms are categorized as B lymphoblastic leukemia/lymphoma and T lymphoblastic leukemia/lymphoma. The B acute lymphoblastic leukemia/lymphoma (ALL) is further classified into B-ALL not otherwise specified or those with recurrent genetic abnormalities. As the name suggests, the cells that proliferate are immature lymphoid cells known as lymphoblasts, which have become halted in their development. Acute lymphoblastic leukemia/lymphoma is rare in the adult population, and the lymphoblasts that are characteristic of the disease show a spectrum of differentiation and have varied cytogenetic alterations. These lymphoblasts commonly have L1 and L2 morphology (FAB classification) with expression of TdT and other primitive lymphoid antigens. Rare cases of ALL with an atypical morphology, immunophenotype, and genetic makeup can pose a diagnostic challenge. We present an unusual case of a precursor B-cell ALL, in an 82-year-old woman, with L3 morphology (Burkitt-like lymphoma) that demonstrates coexpression of TdT and surface light chains. Additionally, the MYC gene translocation and Philadelphia chromosome were also present. Although cases of ALL with co-expression of TdT and surface light chains have been described, to our knowledge no published cases of ALL with this specific immunophenotype and genetic make-up have been reported in the literature. This case further illustrates the need for comprehensive immunophenotyping and genetic testing when establishing an accurate diagnosis of ALL, as this could impact management. Elderly patients with adverse cytogenetic abnormalities and high white blood cell count have a very poor prognosis. 2. Case Presentation An 82-year-old women with a medical history
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