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Regulación de equipos pulverizadores
(CYTED, 2010)
Se entiende por regulación de un equipo pulverizador
a los procedimientos de ajuste para lograr la
distribución de la tasa exacta de un agroquímico
con la mayor homogeneidad posible sobre un
blanco determinado.
Según el Diccionario de la Real...
Diseño y evaluación de un sistema dosificador para pulverizadoras
(Universidad de Chile, 2007)
agroquímicos................................................10
Caudal de inyección ..........................................................................11
Elaboración de prototipo base...
...................................................................................12 Panel de control neumático............................................................................13 Estanque de productos agroquímicos (EPA), utilizado en prototipo............14 Regulación del caudal a inyectar...
...................................................................................12 Panel de control neumático............................................................................13 Estanque de productos agroquímicos (EPA), utilizado en prototipo............14 Regulación del caudal a inyectar...
Detección de Oportunidades para Nuevos Usos y Aplicaciones de Molibdeno en la Industria Química
(Universidad de Chile, 2011)
tendencias de mercado y tecnológicas, las que permitirán evaluar
si las necesidades técnicas encontradas son comercialmente explotables.
La Industria Química está compuesta por los sectores Agroquímicos, Biotecnología,
Catalizadores, Químicos Básicos...
Interplay between stress and osmoregulatory physiology of the anuran Xenopus laevis experimentally exposed to saline and pesticide-contaminated environment
(Universidad de Chile, 2021)
Salinization and pollution (e.g., agrochemicals) are two main environmental stressors leading to
degradation of aquatic ecosystems and consequently alteration in their biological communities.
Amphibians are a highly sensitive group of vertebrates to environmental disturbance of aquatic
ecosystems, however, studies on the combined effect of both stressors on the physiology of anurans
are limited. In the present study, the energetic and biochemical response was evaluated in the invasive
anurus Xenopus laevis acclimatized for 45 days to a high osmotic load (SW), the presence of
chlorpyrifos (P) and the joint exposure to both stressors (SW/P). The results revealed a decrease in
the standard metabolic rate (SMR) in both groups of animals exposed to pesticides. In addition, we
found an increase in the activity of liver citrate synthase (CS) in response to salt stress. In parallel,
the liver acetylcholinesterase (AChE) activity decreased by 50% in animals in the doubly stressed
group, which explained the differences in the detoxification capacity of the xenobiotic. Along the
same lines, we observed an increase in plasma AChE activity in the doubly stressed group, a result
that we attributed to the physiological effects of salt in conjunction with the agrochemical. Finally,
oxidative stress showed a synergistic effect exhibited by an increase in both lipid peroxidation and
concentration of aqueous peroxides found in the experimental group simultaneously exposed to
stressors....
La salinización y la contaminación (e.g., agroquímicos) son dos de los principales factores de estrés ambiental que conducen a la degradación de los ecosistemas acuáticos y, en consecuencia, a la alteración de sus comunidades biológicas. Los...
La salinización y la contaminación (e.g., agroquímicos) son dos de los principales factores de estrés ambiental que conducen a la degradación de los ecosistemas acuáticos y, en consecuencia, a la alteración de sus comunidades biológicas. Los...
Evaluación del potencial de levaduras antárticas como fuentes para el desarrollo de productos biocontroladores de fitopatógenos
(Universidad de Chile, 2014)
Históricamente la agricultura ha pasado por alto la sustentabilidad de la producción
agrícola. El uso de químicos (agroquímicos) ha permitido obtener grandes mejoras en la
producción, sin embargo, una serie de efectos adversos están impactando de...
Historically the agriculh,e has overlooked the sustainability in the agricultural production. The use of chemicals (agro-chemicars) improved the production, but with many adverse effects that impact significantly its sustainability. The pollution originated by the indiscriminate use of agro-chemicals has reduced the biodiversity of "ecosystems", causing instability and increase ofpests and diseases in crops. Fufhe¡more, there are hazards in the production and in the applications of agro-chemicals. For these reasons, the researches and establishments of new altematives for pest and disease management have raised in last years. Due to mentioned above, appears the interest for an ecological control, which is defined as: "any control procedure that reduces the incidence or severity of the disease, or increases the crop production, even when apparently there is no a significant effect in reducing the disease or the inoculum, ard there is no or there is minimal harmful impact on the environment". The biological control, which is the application of antagonistic organisms or derivate (biocontrol), has acquired high worldwide force and a wide variety of new products based on yeasts and other organisms appeared in the market, to combat mainly fungal pathogens, either fruit post-harvest or in the field....
Historically the agriculh,e has overlooked the sustainability in the agricultural production. The use of chemicals (agro-chemicars) improved the production, but with many adverse effects that impact significantly its sustainability. The pollution originated by the indiscriminate use of agro-chemicals has reduced the biodiversity of "ecosystems", causing instability and increase ofpests and diseases in crops. Fufhe¡more, there are hazards in the production and in the applications of agro-chemicals. For these reasons, the researches and establishments of new altematives for pest and disease management have raised in last years. Due to mentioned above, appears the interest for an ecological control, which is defined as: "any control procedure that reduces the incidence or severity of the disease, or increases the crop production, even when apparently there is no a significant effect in reducing the disease or the inoculum, ard there is no or there is minimal harmful impact on the environment". The biological control, which is the application of antagonistic organisms or derivate (biocontrol), has acquired high worldwide force and a wide variety of new products based on yeasts and other organisms appeared in the market, to combat mainly fungal pathogens, either fruit post-harvest or in the field....
Acción de bromuro de metilo sobre el ozono estratosférico y sus consecuencias sobre la agroindustria chilena
(Sociedad Agronómica de Chile, 1995)
Recientes estudios muestran que el bromuro de metilo es una sustancia potencialmente muy destructora de la capa de ozono, pues el radical bromo es 50 veces mas destructivo que el radical cloro. Como producto agroquímico utilizado en Chile en la...
Estudio de Pseudomonas ambientales aisladas desde tomates, su resistencia a agroquímicos, y el efecto de la resistencia a bacteriófagos en la motilidad.
(Universidad de Chile, 2021)
capacidad de infectar plantas de tomate de manera oportunista.
Actualmente, dichas enfermedades son controladas por manejos culturales y aplicaciones preventivas de agroquímicos cúpricos y/o antibióticos. El uso desmedido de estos productos ha favorecido la...
Chile is distinguished by being an important producer of fruits and vegetables worldwide. Among them, the tomato (Solanum lycopersicum) is one of the most consumed vegetables. However, crops are often susceptible to bacterial diseases, the uncontrolled outbreaks of which mean great economic losses. The presence of Pseudomonas species in the soil or epiphytes in plant tissue has been described, considered innocuous but in certain cases they have shown the ability to opportunistically infect tomato plants. Currently, bacterial diseases are controlled by cultural management and preventive applications of copper agrochemicals and / or antibiotics. The excessive use of these has favored the selection of resistant bacterial strains, leading to a decrease in the effectiveness of these control measures. Furthermore, strains of Pseudomonas resistant to copper and streptomycin have been reported in the field. Which aggravates the problem, because it indicates that environmental strains could also act as reservoirs of resistance. For this reason, it is necessary to search for new strategies for their control, with bacteriophages being a potential biocontroller tool. However, the acquisition of this type of defense could have a cost in the cellular “fitness” for some cases. In this work, environmental Pseudomonas were characterized by MLSA, which turned out to be phylogenetically close since their genetic similarities of distances fluctuate between 0,01 and 0,08. Furthermore, no correlation is found between their genetic grouping and the origin of isolation. It should be noted that individual analysis of the cts gene resulted in the same phylogroups. On the other hand, 79% of the strains were resistant to streptomycin and copper. Two phage-susceptible strains of Pseudomonas generated phage-resistant variants, which were characterized by changes in their motility and tolerance to copper. In all phage resistant variants derived from the parental strain designated T1.9, the average colony diameter achieved for swarming was halved. In the case of swimming, it increased between 14% and 19%. All the resistant variants derived from the AI_1 strain did not show statistically significant changes in either of the two types of swimming. Regarding tolerance to copper, all the phage resistant strains derived from T1.9, reached averages of OD600 higher by 56%, 43.6% and 49.5% than the parental strain, for a concentration of 3,5 mM CuSO4 at 48h. While for the AI_1 strain there were only significant differences for the variants resistant to Fago18, which reached an OD600 33.5% higher. Finally, this is the first study that reports changes in the motility and copper tolerance of environmental Pseudomonas resistant to copper and streptomycin, when they acquire resistance to phages. These changes depend both on the tendency of the bacteria to acquire this resistance and on the mechanisms they use to do so. In this analysis, the T1.9 strain tended to acquire resistance to three phages and showed significant changes in motility and tolerance to copper. Thus, using phages as a biocontrol tool for pathogenic bacteria could generate less or more virulent strains....
Chile is distinguished by being an important producer of fruits and vegetables worldwide. Among them, the tomato (Solanum lycopersicum) is one of the most consumed vegetables. However, crops are often susceptible to bacterial diseases, the uncontrolled outbreaks of which mean great economic losses. The presence of Pseudomonas species in the soil or epiphytes in plant tissue has been described, considered innocuous but in certain cases they have shown the ability to opportunistically infect tomato plants. Currently, bacterial diseases are controlled by cultural management and preventive applications of copper agrochemicals and / or antibiotics. The excessive use of these has favored the selection of resistant bacterial strains, leading to a decrease in the effectiveness of these control measures. Furthermore, strains of Pseudomonas resistant to copper and streptomycin have been reported in the field. Which aggravates the problem, because it indicates that environmental strains could also act as reservoirs of resistance. For this reason, it is necessary to search for new strategies for their control, with bacteriophages being a potential biocontroller tool. However, the acquisition of this type of defense could have a cost in the cellular “fitness” for some cases. In this work, environmental Pseudomonas were characterized by MLSA, which turned out to be phylogenetically close since their genetic similarities of distances fluctuate between 0,01 and 0,08. Furthermore, no correlation is found between their genetic grouping and the origin of isolation. It should be noted that individual analysis of the cts gene resulted in the same phylogroups. On the other hand, 79% of the strains were resistant to streptomycin and copper. Two phage-susceptible strains of Pseudomonas generated phage-resistant variants, which were characterized by changes in their motility and tolerance to copper. In all phage resistant variants derived from the parental strain designated T1.9, the average colony diameter achieved for swarming was halved. In the case of swimming, it increased between 14% and 19%. All the resistant variants derived from the AI_1 strain did not show statistically significant changes in either of the two types of swimming. Regarding tolerance to copper, all the phage resistant strains derived from T1.9, reached averages of OD600 higher by 56%, 43.6% and 49.5% than the parental strain, for a concentration of 3,5 mM CuSO4 at 48h. While for the AI_1 strain there were only significant differences for the variants resistant to Fago18, which reached an OD600 33.5% higher. Finally, this is the first study that reports changes in the motility and copper tolerance of environmental Pseudomonas resistant to copper and streptomycin, when they acquire resistance to phages. These changes depend both on the tendency of the bacteria to acquire this resistance and on the mechanisms they use to do so. In this analysis, the T1.9 strain tended to acquire resistance to three phages and showed significant changes in motility and tolerance to copper. Thus, using phages as a biocontrol tool for pathogenic bacteria could generate less or more virulent strains....
Diseño de estrategia para la introducción de una innovación tecnológica destinada al proceso de aplicación de agroquímicos y producción de fruta fresca en Chile
(Universidad de Chile, 2014)
DISEÑO DE ESTRATEGIA PARA LA INTRODUCCIÓN DE UNA INNOVACIÓN
TECNOLÓGICA DESTINADA AL PROCESO DE APLICACIÓN DE AGROQUÍMICOS
Y PRODUCCIÓN DE FRUTA FRESCA EN CHILE
MEMORIA PARA OPTAR AL TÍTULO DE INGENIERO CIVIL...
UNA INNOVACIÓN TECNOLÓGICA DESTINADA AL PROCESO DE APLICACIÓN DE AGROQUÍMICOS Y PRODUCCIÓN DE FRUTA FRESCA EN CHILE Existen en Chile deficiencia en la aplicación de plaguicidas. La regulación de equipos pulverizadores y la falta de un programa de...
UNA INNOVACIÓN TECNOLÓGICA DESTINADA AL PROCESO DE APLICACIÓN DE AGROQUÍMICOS Y PRODUCCIÓN DE FRUTA FRESCA EN CHILE Existen en Chile deficiencia en la aplicación de plaguicidas. La regulación de equipos pulverizadores y la falta de un programa de...
Caracterización fisiológica, molecular e identificación bioquímica de metabolitos y enzimas de cepas rizobacterianas con aptitud nematicida sobre Xiphinema index (Thorne y Allen) y Meloidogyne ethiopica (Whitehead)
(Universidad de Chile, 2014)
Las Rizobacterias Promotoras de Crecimiento Vegetal (PGPR), son bacterias benéficas que viven en asociación con las raíces de las plantas, su uso en la agricultura puede disminuir la dependencia a agroquímicos tóxicos para el medio ambiente y la...
The plant grown-promoting rhizobacteria are beneficial bacteria that live in association with plant roots, their use in the agriculture can reduce the dependence on toxic chemicalsthat affect the environment and human health. Filtrates of seven rhizobacterial strains, with previously proved nematicidalproperties, were in vitroevaluated onMeloidogyne ethiopica and Xiphinema indexplant-parasitic nematodes. Sets of chemical tests were performed to determine the presence of certain metabolites and enzymes with possible nematicidal activity. The results after 72 hours exposure to rhizobacterial filtratesshowed a mortality of 94%and 100% onXiphinema index assayed with Bacillus amyloliquefaciens consortium FR203A and Pseudomonas fluorescensFP805PU, respectively. The same bacterial strains presented mortalities of 76 and 83%on Meloidogyne ethiopica, repectively. Concerning the otherbacteria strains, the mortality varied from 54-81% onXiphinema index and 44-59% onMeloidogyne ethiopica.Concerning the Meloidogyne ethiopica egg hatching assay, significant differenceagainst control treatmentoccurs only with five bacteria strains and the highest hatching control percentages presentedBrevibacterium frigoritoleransFB37BR, B. amyloliquefaciens consortium FR203A and B. thuringiensisFS213P. All rhizobacterial strains presented activity for at least five of themetabolitesand the exoenzymes considered. The rhizobacterial strains tested possess nematicidal compounds, which may be and interesting alternative of control....
The plant grown-promoting rhizobacteria are beneficial bacteria that live in association with plant roots, their use in the agriculture can reduce the dependence on toxic chemicalsthat affect the environment and human health. Filtrates of seven rhizobacterial strains, with previously proved nematicidalproperties, were in vitroevaluated onMeloidogyne ethiopica and Xiphinema indexplant-parasitic nematodes. Sets of chemical tests were performed to determine the presence of certain metabolites and enzymes with possible nematicidal activity. The results after 72 hours exposure to rhizobacterial filtratesshowed a mortality of 94%and 100% onXiphinema index assayed with Bacillus amyloliquefaciens consortium FR203A and Pseudomonas fluorescensFP805PU, respectively. The same bacterial strains presented mortalities of 76 and 83%on Meloidogyne ethiopica, repectively. Concerning the otherbacteria strains, the mortality varied from 54-81% onXiphinema index and 44-59% onMeloidogyne ethiopica.Concerning the Meloidogyne ethiopica egg hatching assay, significant differenceagainst control treatmentoccurs only with five bacteria strains and the highest hatching control percentages presentedBrevibacterium frigoritoleransFB37BR, B. amyloliquefaciens consortium FR203A and B. thuringiensisFS213P. All rhizobacterial strains presented activity for at least five of themetabolitesand the exoenzymes considered. The rhizobacterial strains tested possess nematicidal compounds, which may be and interesting alternative of control....
Impactos ambientales del aceite de oliva y evaluación de un portafolio de medidas para su mitigación. Estudio de caso de Comercial Soho
(Universidad de Chile, 2014)
ambientales de la producción del aceite de oliva. Esto permite identificar que los principales focos de impacto se relacionan con el uso de agroquímicos (18% de los impactos del sistema medidos en puntos normalizados), el proceso de riego (25%), los residuos...