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Desarrollo de modelos QSAR perfectibles para predecir la adsorción de plaguicidas orgánicos en suelos en condiciones de campo : soporte a la efectividad y racionalidad de la toma de decisiones medioambientales
(Universidad de Chile, 2022)
Los plaguicidas son agroquímicos usados para mejorar la productividad silvoagrícola, cuya dinámica ambiental en suelos está controlada principalmente por el proceso de adsorción, caracterizado mediante el coeficiente de adsorción Kf, cuyo valor es...
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...
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....
Sensibilidad in vitro E in vivo de cepas de Botrytis cinerea y Penicillium expansum aisladas de manzanas en poscosecha a : tiabendazol, fludioxonil y productos químicos de origen natural
(2011)
las enfermedades en poscosecha de frutas. El control químico es una
práctica fundamental para prevenir las pudriciones fungosas de poscosecha en frutas
(Auger, 1988). Este autor señala que los tratamientos después de la cosecha con
agroquímicos...
agroquímicos bastante eficientes, es necesario emplearlos en combinación con productos de diferentes mecanismos de acción o en casos extremos, descontinuar su uso buscando otras alternativas (Errampalli, 2004). Morales (1989), señala que esta situación puede...
agroquímicos bastante eficientes, es necesario emplearlos en combinación con productos de diferentes mecanismos de acción o en casos extremos, descontinuar su uso buscando otras alternativas (Errampalli, 2004). Morales (1989), señala que esta situación puede...
Use of anti drift nozzles in control of perennial weeds in vineyard nurseries
(Univ. Nacional Cuyo, Argentina, 2020)
es la mayor superficie de frutales, con un efecto en una
alta tasa de uso de agroquímicos, sobre todo en los viveros, en los cuales las malezas son un factor limitante, siendo Cyperus rotundus L., Sorghum halepense (L. Pers) y Cynodon
dactylon...
(L. Pers), las especies de más difícil control. Este cambio requiere que las aplica- ciones de agroquímicos como los herbicidas sean más precisos y seguros con el medio ambiente, evitando además el daño por deriva, sobre todo por la reducida...
(L. Pers), las especies de más difícil control. Este cambio requiere que las aplica- ciones de agroquímicos como los herbicidas sean más precisos y seguros con el medio ambiente, evitando además el daño por deriva, sobre todo por la reducida...
" Propuesta de monitoreo en una potencial contaminación de pesticidas en fuentes de agua para el consumo humano del sector altoandino del valle del Elqui. IV Region
(Universidad de Chile, 2011)
invieno y
verano' en donde se logra apreciar la influencia de los cambios estacionales y la
aplicación de agroquímicos de la zona.
Los ingredientes activos de los pesticidas seleccionados para la propuesta de monitoreo
fueron 6: triadimefon, metalaxil...
It made a proposal for monitoring of pesticides in source drinking wáter in the commune of Paihuano, belonging to the Elqui Province, Coquimbo Region. In the proposal, it was determined the location of sampling points, which one correspond to the locations of wáter withdrawal for consumption human, either surface or underground of the area APR and the SS Aguas del Valle and the wells of the monitoring stations of the DGA, forming nine locations. It was determined that the most suitable sampling period is January, which is relied on the dates of pesticide applications and suggests that the ideal frequency of monitoring was a multi-year or more widespread in winter a¡d summer seasons, where he manages assess the impact of seasonal changes and application of agrochemicals in the area' The pesticide active ingredients selected for the proposal for monitoring were 6: triadimefon, metalaxyl, myclobutanil, boscalid, simazine and Penconazole. These pesticides were obtained from a giggest list, which one was obtained from pesticides applied to crops of grapes of the commune. To determine which pesticides would have a potential water pollution in the area, they were filtered fiom their physicochemical characteristics. In the ñrst instance to those active ingredients with some ability to leach into the waters underground, where mainly consider adsorption and persistence in soil. Also was considered for those with some solubility, supplemented by the potential for runoff, in order to include surface water. Then described the characteristics of all active ingredients and thei¡ respective metabolites, if corresponds, were detailed, which was considered units sale, toxicity, solubility and degradation. Finally these pesticides were analyzed according to their behavior in systems soi1, water, air and sediment-water indicating in each case the reaction degradation, if corresponds. To each of them have suggested an analyical technique to be determined and a sampling methodology....
It made a proposal for monitoring of pesticides in source drinking wáter in the commune of Paihuano, belonging to the Elqui Province, Coquimbo Region. In the proposal, it was determined the location of sampling points, which one correspond to the locations of wáter withdrawal for consumption human, either surface or underground of the area APR and the SS Aguas del Valle and the wells of the monitoring stations of the DGA, forming nine locations. It was determined that the most suitable sampling period is January, which is relied on the dates of pesticide applications and suggests that the ideal frequency of monitoring was a multi-year or more widespread in winter a¡d summer seasons, where he manages assess the impact of seasonal changes and application of agrochemicals in the area' The pesticide active ingredients selected for the proposal for monitoring were 6: triadimefon, metalaxyl, myclobutanil, boscalid, simazine and Penconazole. These pesticides were obtained from a giggest list, which one was obtained from pesticides applied to crops of grapes of the commune. To determine which pesticides would have a potential water pollution in the area, they were filtered fiom their physicochemical characteristics. In the ñrst instance to those active ingredients with some ability to leach into the waters underground, where mainly consider adsorption and persistence in soil. Also was considered for those with some solubility, supplemented by the potential for runoff, in order to include surface water. Then described the characteristics of all active ingredients and thei¡ respective metabolites, if corresponds, were detailed, which was considered units sale, toxicity, solubility and degradation. Finally these pesticides were analyzed according to their behavior in systems soi1, water, air and sediment-water indicating in each case the reaction degradation, if corresponds. To each of them have suggested an analyical technique to be determined and a sampling methodology....
“Genómica comparativa de cepas de Xanthomonas Arborícola pv Juglandis asociadas a brotes de peste negra en nogales chilenos”
(Universidad de Chile, 2022)
base de cobre. El uso reiterado de estos agroquímicos cúpricos ha propiciado la selección de cepas resistentes de Xaj. Se ha descrito genes involucrados en mecanismos de resistencia al metal en Xanthomonas fitopatógenas, principalmente del operón cop...
Xanthomonas arboricola pv juglandis (Xaj) is the pathogen that causes the Walnut Blight, a bacterial disease responsible for the greatest productive losses worldwide. Its control is based on cultural control and application of copper-based pesticides. The repeated use of these copper agrochemicals has led to the selection of resistant strain of Xaj. Genes involved in metal resistance mechanisms have been described in phytopathogenic, mainly the cop operon. However, all the genetic determinants in national Xaj are still completely unknown. Therefore, the aim was to investigate the genetic diversity of Xaj strains associated with outbreaks of Walnut Blight in Chilean walnut trees. Comparative genomics on the published national and international Xaj genomes was performed, through bioinformatics tools, thus characterization the genetic diversity and the content of copper tolerance determinants. The genetic diversity of the Xaj strains was low (≥95% identity). Both the copABL operon and cation transport genes were identified in the Xaj genomes. In addition, three Genomic Islands (GIs) were found to contained cop genes and genes for resistance to other cations and heavy metals. Furthermore, these were found in in mobile genetic elements in other environmental pathogens, allowing to speculate a possible horizontal origin of these genes in Xaj. No copper tolerance determinants encoded in prophage-like elements (Pp) were found. A hypothetical evolutionary pathway of Xaj was proposed, considering the early and/or contemporary acquisition of IGs, Pp and the central genome-based phylogeny. Finally, the results obtained did not allow to explain the differences in the copper resistance phenotype of the national Xaj strains....
Xanthomonas arboricola pv juglandis (Xaj) is the pathogen that causes the Walnut Blight, a bacterial disease responsible for the greatest productive losses worldwide. Its control is based on cultural control and application of copper-based pesticides. The repeated use of these copper agrochemicals has led to the selection of resistant strain of Xaj. Genes involved in metal resistance mechanisms have been described in phytopathogenic, mainly the cop operon. However, all the genetic determinants in national Xaj are still completely unknown. Therefore, the aim was to investigate the genetic diversity of Xaj strains associated with outbreaks of Walnut Blight in Chilean walnut trees. Comparative genomics on the published national and international Xaj genomes was performed, through bioinformatics tools, thus characterization the genetic diversity and the content of copper tolerance determinants. The genetic diversity of the Xaj strains was low (≥95% identity). Both the copABL operon and cation transport genes were identified in the Xaj genomes. In addition, three Genomic Islands (GIs) were found to contained cop genes and genes for resistance to other cations and heavy metals. Furthermore, these were found in in mobile genetic elements in other environmental pathogens, allowing to speculate a possible horizontal origin of these genes in Xaj. No copper tolerance determinants encoded in prophage-like elements (Pp) were found. A hypothetical evolutionary pathway of Xaj was proposed, considering the early and/or contemporary acquisition of IGs, Pp and the central genome-based phylogeny. Finally, the results obtained did not allow to explain the differences in the copper resistance phenotype of the national Xaj strains....
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...
Mercado de fertilizantes foliares en Chile: situación actual y perspectivas
(Universidad de Chile, 2014)
comercializa 8.001.000 L por un valor total
de US$ 49.251.900. El mayor volumen es 1.170.000 L de fosfitos y el mayor monto es US$
7.070.000 en extracto de algas. El monto total aproximado comercializado el año 2012 por
el canal de distribución en agroquímicos...
The present study describe the market and characterize the commercialization of foliar fertilizers in Chile, using information from different sources and complementing the profile review with semi-structured deep interviews to the distribution channel. At 2012 the Chilean foliar fertilizers imports were 4.757.609 kg by a total value of U.S. $ 14.167.983. There are different kinds and types of foliar fertilizers: Calcium correctors, Magnesium correctors, Potassium correctors, Copper correctors, Boron correctors, Amino Acids ( both leaf application and root application ) , with cytoquinine action , seaweed extracts , humic Amendment, physiopathy Correctors , salinity Correctors, phosphites and nitrogens Controlled Release . The main imported volumes at 2012 correspond to 738.481 kg of nitrogens controlled release, 598.297 kg phosphites and 529.808 kg of calcium correctors. There are big differences in terms of prices and margins for the same type of imported product and attractive margins for brand positioning. It`s difficult to quantify the manufacturing industry foliar fertilizers in Chile. The domestic market for foliar fertilizers sold 8.001.000 L for a total value of U.S. $49.251.900. The largest volume is 1.170.000 L of phosphites and the larger amount is U.S. $7.070.000 in seaweed extract. The estimated total amount sold in 2012 by distribution channel including agrochemicals foliar fertilizers was US$ 433 million. The decreasing participation in this sale is: COPEVAL, COAGRA, M y V, GMT and CALS with 71.6 % of the national market. The most demanding market segments foliar fertilizers are fruit and vegetables on the other hand, the lowest demanded are the extensive crops. The foliar fertilizers market is menace by the increasing reduction margins, wrong negotiations affecting the profitability of the business and the growing number of companies participating in the market. Finally, opportunities come from the increased of fruit surface with the intensification of their management, incorporating the use of foliar fertilizers on extensive crops, thus, refine strategies alliances with the distribution channel allowing beneficial negotiations for both sides....
The present study describe the market and characterize the commercialization of foliar fertilizers in Chile, using information from different sources and complementing the profile review with semi-structured deep interviews to the distribution channel. At 2012 the Chilean foliar fertilizers imports were 4.757.609 kg by a total value of U.S. $ 14.167.983. There are different kinds and types of foliar fertilizers: Calcium correctors, Magnesium correctors, Potassium correctors, Copper correctors, Boron correctors, Amino Acids ( both leaf application and root application ) , with cytoquinine action , seaweed extracts , humic Amendment, physiopathy Correctors , salinity Correctors, phosphites and nitrogens Controlled Release . The main imported volumes at 2012 correspond to 738.481 kg of nitrogens controlled release, 598.297 kg phosphites and 529.808 kg of calcium correctors. There are big differences in terms of prices and margins for the same type of imported product and attractive margins for brand positioning. It`s difficult to quantify the manufacturing industry foliar fertilizers in Chile. The domestic market for foliar fertilizers sold 8.001.000 L for a total value of U.S. $49.251.900. The largest volume is 1.170.000 L of phosphites and the larger amount is U.S. $7.070.000 in seaweed extract. The estimated total amount sold in 2012 by distribution channel including agrochemicals foliar fertilizers was US$ 433 million. The decreasing participation in this sale is: COPEVAL, COAGRA, M y V, GMT and CALS with 71.6 % of the national market. The most demanding market segments foliar fertilizers are fruit and vegetables on the other hand, the lowest demanded are the extensive crops. The foliar fertilizers market is menace by the increasing reduction margins, wrong negotiations affecting the profitability of the business and the growing number of companies participating in the market. Finally, opportunities come from the increased of fruit surface with the intensification of their management, incorporating the use of foliar fertilizers on extensive crops, thus, refine strategies alliances with the distribution channel allowing beneficial negotiations for both sides....
Plataforma para la floricultura en Ocoa. Centro de producción y turismo florícola en Ocoa. Comuna de Hijuelas, V región de Valparaíso
(Universidad de Chile, 2013)
calidad final de las
flores, logrando mayor rentabilidad y
competitividad en el mercado internacional y
nacional.
-Colaborar en infraestructura que ayude a
responder y adoptar la normativa fitosanitaria
vigente (agroquímicos), lo que facilitaría el...