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Propuesta de un sistema de control de gestión para la unidad de vegetales de la Empresa Monsanto S.A.
(Universidad de Chile, 2019-12)
nivel mundial por la venta de semillas y agroquímicos de alta calidad y rendimiento. Es una empresa norteamericana, por lo que parte de sus lineamientos y directrices vienen dados por la casa matriz. En este trabajo se analizará la unidad de vegetales...
Modelo de articulación territorial para el campus Antumapu de la Universidad de Chile
(Universidad de Chile, 2018)
Estudio de adsorción de plaguicidas en sedimentos fluviales y optimización de técnicas de recuperación.
(Universidad de Chile, 2019-03)
suministrado una gran cantidad de agroquímicos de alta toxicidad y
persistencia, cuyos efectos sobre el hombre y el equilibrio del ecosistema están
relacionados con su uso inapropiado y desmedido. No obstante, también existen
evidencias de los beneficios que...
plaguicidas de uso Agrícola elaborado por el Servicio Agrícola y Ganadero (2012), se informa que las ventas de fungicidas y herbicidas 4 equivalen a un 47% y un 21% (Figura 1), siendo los tipos de agroquímicos más vendidos en Chile...
plaguicidas de uso Agrícola elaborado por el Servicio Agrícola y Ganadero (2012), se informa que las ventas de fungicidas y herbicidas 4 equivalen a un 47% y un 21% (Figura 1), siendo los tipos de agroquímicos más vendidos en Chile...
Efectos del cobre en altas concentraciones sobre la diversidad de las comunidades bacterianas de suelos agrícolas de la región de Valparaíso
(Universidad de Chile, 2010)
El valle de Aconcagua es una de las principales zonas agrícolas ubicada en la región de Valparaíso, Chile. La minería del cobre y el empleo de agroquímicos que contienen cobre, ha provocado un incremento en la concentración de este metal en este...
The Aconcagua valley, located in the Valparaiso region, is one of the main agricultural areas of Chile. Copper mining and the massive use of copper agrochemicals has led to an increase of copper concentration in soils. Copper reduces biomass and bacterial metabolic activity in soils. Therefore, copper reduces agricultural soils fertility and causes ecosystem damage. This thesis postulates that copper at high concentrations in agricultural soils decreases the bacterial community diversity and increases copper-tolerant bacteria. Soils from the Aconcagua valley with high concentrations of copper (379, 520 y 784 mg/kg) and a soil from the Casablanca valley (20 mg/kg) were analyzed. Heterotrophic bacteria and copper-tolerant bacteria from soils were determined by culture-dependent techniques. Copper resistant bacteria were isolated. Strains with high copper-tolerance were further characterized. The diversity and abundance of bacterial communities in Aconcagua and Casablanca valleys soils were determined by denaturing gradient gel electrophoresis (DGGE). The number of heterotrophic bacteria was similar in all soils. The number of copper-tolerant heterotrophic bacteria was significantly higher in copper-contaminated soils than in control soils. 92 bacterial strains were isolated. Five strains, C21, O4, O12, A32, and A55, showed high resistance to copper (MIC 3.1 - 4.7 mM). These 5 strains possess the copA gene that encodes CopA, a protein related to copper resistance. The strains O12, A32 and A55 showed tolerance to nickel (17 mM) and possessed the nccA gene that encodes the protein NccA confering resistance to this metal. Strains C21 and O4 were tolerant to chromate (4.3 Mm). Plasmids ware detected in isolates O12 and A32, which may encode heavy metal resistance genes. The growth rate of strain O12 was not affected by the presence of copper (0,8 mM and 2,4 mM). The richness and diversity index (H) indicated no significant differences between communities from copper-contaminated soils and control soil (<0,05). The copper tolerant strains isolated from contaminated soils suggest selective pressure of copper to bacterial communities. The selective pressure of copper increased copper tolerance of bacterial communities....
The Aconcagua valley, located in the Valparaiso region, is one of the main agricultural areas of Chile. Copper mining and the massive use of copper agrochemicals has led to an increase of copper concentration in soils. Copper reduces biomass and bacterial metabolic activity in soils. Therefore, copper reduces agricultural soils fertility and causes ecosystem damage. This thesis postulates that copper at high concentrations in agricultural soils decreases the bacterial community diversity and increases copper-tolerant bacteria. Soils from the Aconcagua valley with high concentrations of copper (379, 520 y 784 mg/kg) and a soil from the Casablanca valley (20 mg/kg) were analyzed. Heterotrophic bacteria and copper-tolerant bacteria from soils were determined by culture-dependent techniques. Copper resistant bacteria were isolated. Strains with high copper-tolerance were further characterized. The diversity and abundance of bacterial communities in Aconcagua and Casablanca valleys soils were determined by denaturing gradient gel electrophoresis (DGGE). The number of heterotrophic bacteria was similar in all soils. The number of copper-tolerant heterotrophic bacteria was significantly higher in copper-contaminated soils than in control soils. 92 bacterial strains were isolated. Five strains, C21, O4, O12, A32, and A55, showed high resistance to copper (MIC 3.1 - 4.7 mM). These 5 strains possess the copA gene that encodes CopA, a protein related to copper resistance. The strains O12, A32 and A55 showed tolerance to nickel (17 mM) and possessed the nccA gene that encodes the protein NccA confering resistance to this metal. Strains C21 and O4 were tolerant to chromate (4.3 Mm). Plasmids ware detected in isolates O12 and A32, which may encode heavy metal resistance genes. The growth rate of strain O12 was not affected by the presence of copper (0,8 mM and 2,4 mM). The richness and diversity index (H) indicated no significant differences between communities from copper-contaminated soils and control soil (<0,05). The copper tolerant strains isolated from contaminated soils suggest selective pressure of copper to bacterial communities. The selective pressure of copper increased copper tolerance of bacterial communities....
Producción de ácido pirúvico y gliceraldehído a partir de alginato mediante inmovilización enzimática en superficie celular
(Universidad de Chile, 2016)
: uso de suelos arables/deforestación, agua dulce, agroquímicos y sus respectivos impactos derivados. El alginato, obtenido desde maroalgas, se presenta como una interesante alternativa por cuanto su producción evita la mayor parte de estos impactos...
Frecuencia de visitas de coccinélidos nativos y exóticos a áfidos centinela en alfalfa
(Universidad de Chile, 2021-05)
niveles de depredadores naturales, por sobre el uso de agroquímicos generalistas....
Coccinellids (Coleoptera: Coccinellidae) are recognized for their importance as biological control agents. In Chile they are abundant and diverse in alfalfa (Medicago sativa L.), a crop whose most abundant pests are aphids. The general objective of this study was to estimate, from digital monitoring of sentinel aphids, the role of native and exotic coccinellids in the consumption of aphids in alfalfa and their participation in the trophic networks, in scenarios with different abundance of aphids. Specifically, the objectives were to: (1) know the potential coccinellid species that consume aphids; (2) evaluate if the frequency of visits to sentinel aphids varies between native and exotic coccinellids; (3) evaluate if the visits of native and exotic coccinellids to sentinel aphids vary according to the abundance of them and of aphids in the crop; and (4) analyze the trophic networks under conditions of high and low abundance of aphids in the crop. For this, experiments with sentinel aphids were carried out 15 times during the spring of 2019 in alfalfa crops in the south of the Metropolitan Region. The experiments were monitored with video cameras to record the natural enemies species that visited the cards. Within the 750 hours of recording collected, a total of 2369 visits by coccinellids were recorded. They were the most common aphidophagous arthropods in alfalfa, with over 86% of the total visits. Three exotic and two native species were recorded, with the exotic Hippodamia variegata (Goeze) representing about 70% of the visits, followed by the native Eriopis chilensis Hofmann (15.6%) and Eriopis eschscholtzii Mulsant (11.2%). Visits by Hippodamia convergens Guerin-Meneville (2.1%) and Harmonia axyridis (Pallas) (1.5%) occurred in a smaller proportion. The frequency of visits of exotic coccinellids to cards with sentinel aphids was significantly higher (73.2%) than that of natives (26.8%) (P<0.05). On the other hand, the records of coccinellids visiting sentinel aphids and the abundance of the same species of coccinellids in the crop showed a positive and significant association, indicating that the methodology used adequately records these interactions. A negative and significant correlation was also found between the visits of native coccinellids and the abundance of aphids in the crop, which supports the results of previous studies that show the important role of native species in the biological control of aphids in alfalfa. The quantitative indices calculated for the trophic webs did not vary significantly between conditions of high and low abundance of aphids. The results of this study, compared with similar evaluations in the past, suggests that native species of coccinellids have decreased their abundance in alfalfa crops in recent years, which highlights the idea of taking measures to favor mechanisms to increase the levels of natural predators, over the use of general agrochemicals....
Coccinellids (Coleoptera: Coccinellidae) are recognized for their importance as biological control agents. In Chile they are abundant and diverse in alfalfa (Medicago sativa L.), a crop whose most abundant pests are aphids. The general objective of this study was to estimate, from digital monitoring of sentinel aphids, the role of native and exotic coccinellids in the consumption of aphids in alfalfa and their participation in the trophic networks, in scenarios with different abundance of aphids. Specifically, the objectives were to: (1) know the potential coccinellid species that consume aphids; (2) evaluate if the frequency of visits to sentinel aphids varies between native and exotic coccinellids; (3) evaluate if the visits of native and exotic coccinellids to sentinel aphids vary according to the abundance of them and of aphids in the crop; and (4) analyze the trophic networks under conditions of high and low abundance of aphids in the crop. For this, experiments with sentinel aphids were carried out 15 times during the spring of 2019 in alfalfa crops in the south of the Metropolitan Region. The experiments were monitored with video cameras to record the natural enemies species that visited the cards. Within the 750 hours of recording collected, a total of 2369 visits by coccinellids were recorded. They were the most common aphidophagous arthropods in alfalfa, with over 86% of the total visits. Three exotic and two native species were recorded, with the exotic Hippodamia variegata (Goeze) representing about 70% of the visits, followed by the native Eriopis chilensis Hofmann (15.6%) and Eriopis eschscholtzii Mulsant (11.2%). Visits by Hippodamia convergens Guerin-Meneville (2.1%) and Harmonia axyridis (Pallas) (1.5%) occurred in a smaller proportion. The frequency of visits of exotic coccinellids to cards with sentinel aphids was significantly higher (73.2%) than that of natives (26.8%) (P<0.05). On the other hand, the records of coccinellids visiting sentinel aphids and the abundance of the same species of coccinellids in the crop showed a positive and significant association, indicating that the methodology used adequately records these interactions. A negative and significant correlation was also found between the visits of native coccinellids and the abundance of aphids in the crop, which supports the results of previous studies that show the important role of native species in the biological control of aphids in alfalfa. The quantitative indices calculated for the trophic webs did not vary significantly between conditions of high and low abundance of aphids. The results of this study, compared with similar evaluations in the past, suggests that native species of coccinellids have decreased their abundance in alfalfa crops in recent years, which highlights the idea of taking measures to favor mechanisms to increase the levels of natural predators, over the use of general agrochemicals....
Costos de un programa de Buenas Prácticas Ganaderas en pequeños productores de bovinos de carne en la XI Región de Aysén
(Universidad de Chile, 2005)
correspondiente para desempeñar la nueva tarea
100 42
Capacitar sobre labores
específicas El personal que trabaja en su predio ha sido entrenado para desarrollar la
función que se le asigno
100 67
Las personas que manejan drogas veterinarias o agroquímicos...
Evaluación de biofiltros para reducir pérdidas de nitrógeno en períodos de barbecho de suelos cultivados con maíz
(Universidad de Chile, 2014)
han
ocasionado impactos negativos en los ecosistemas acuáticos, en lo que se refiere
específicamente al uso excesivo de agroquímicos que, como consecuencia, han generado
por ejemplo acumulaciones importantes de formas nitrogenadas en cuerpos de...
Diseño de estrategia de desarrollo de empresa
(Universidad de Chile, 2012)
, frutos, procesos de manejos, logística, embalaje, control
de calidad, aplicación de agroquímicos. Además de incluir en el sistema la
retroalimentación que permite las correcciones de las acciones anualmente[2].
4 DISEÑO DE LA ESTRATEGIA
4.1 EJECUCIÓN...
las acciones a realizar. O1 Incrementar el porcentaje de la fruta a exportación en las distintas variedades producidas Acciones Responsables Periodo Frecuencia A11 Generar planificación preventiva con Productos Agroquímicos a árbol y terreno. Que...
las acciones a realizar. O1 Incrementar el porcentaje de la fruta a exportación en las distintas variedades producidas Acciones Responsables Periodo Frecuencia A11 Generar planificación preventiva con Productos Agroquímicos a árbol y terreno. Que...