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Utilización de Microsatélites para la Determinación de la Polilla de la Manzana Cydia pomonella L. (Lepidoptera: Tortricidae) en Chile Central
Espinoza,Juan L; Fuentes-Contreras,Eduardo; Barros,Wilson; Ramírez,Claudio;
Agricultura Técnica , 2007, DOI: 10.4067/S0365-28072007000300003
Abstract: codling moth (cydia pomonella l.) is the main pest of pip fruits worldwide. despite its economic importance, little is known about the genetic structure and patterns of movement at local and regional scale, important aspects for establishing a control strategy for this pest. an analysis of genetic variability on six populations of c. pomonella using microsatellite was performed in the two major apple (malus domestica borkh.) growing regions of central chile. in spite of geographic distances between some populations (aprox. 180 km), there was little genetic differentiation among populations (fst = 0.0-0.0097 and gst = 0.005-0.127), without isolation by distance, and high levels of gene flow (nm ≈ 250). high frequencies of null alleles were found over all loci across populations (na = 0.292) which seem to explain the significant heterozygote deficiencies found. approximatelly 98% of the variance was found within individuals and very little at the other hierarchical levels. the high levels of genetic diversity and gene flow detected seem to indicate that the codling moth populations studied in both regions have an almost continuous distribution
Utilización de Microsatélites para la Determinación de la Polilla de la Manzana Cydia pomonella L. (Lepidoptera: Tortricidae) en Chile Central Utilization of Microsatellites to Determine Genetic Variability of the Codling Moth Cydia pomonella L. (Lepidoptera: Tortricidae) in Central Chile
Juan L Espinoza,Eduardo Fuentes-Contreras,Wilson Barros,Claudio Ramírez
Agricultura Técnica , 2007,
Abstract: La polilla de la manzana (Cydia pomonella L.) es la plaga más importante de los frutales pomáceos en el mundo. A pesar de su gran importancia económica, poco se sabe acerca de su estructura genética y patrones de movimiento a escala local y regional, aspectos importantes para establecer una estrategia de control de esta plaga. Mediante la utilización de microsatélites se realizó un análisis de la variabilidad genética de seis poblaciones de la polilla de la manzana en las dos principales regiones productoras de manzanas (Malus domestica Borkh.) en Chile Central. A pesar de las distancias geográficas entre algunas poblaciones (aprox. 180 km), se encontraron bajos coeficientes de diferenciación genética entre poblaciones (F ST = 0,0-0,00097 y G ST = 0,005-0,127), sin presencia de aislamiento por distancia, y con altos niveles de flujo génico (Nm ≈ 250). Se encontraron altas frecuencias de alelos nulos (Na = 0,292) para todos los loci, a través de las poblaciones analizadas, lo que explicaría el significativo déficit de heterocigotos encontrado. Aproximadamente un 98% de la variabilidad genética encontrada corresponde a una variación intraindividual, atribuyéndose prácticamente nada a los demás niveles jerárquicos. La alta diversidad génica y los altos niveles de flujo génico parecen indicar que las poblaciones estudiadas de la polilla de la manzana en ambas regiones estudiadas están distribuidas formando casi un continuo Codling moth (Cydia pomonella L.) is the main pest of pip fruits worldwide. Despite its economic importance, little is known about the genetic structure and patterns of movement at local and regional scale, important aspects for establishing a control strategy for this pest. An analysis of genetic variability on six populations of C. pomonella using microsatellite was performed in the two major apple (Malus domestica Borkh.) growing regions of Central Chile. In spite of geographic distances between some populations (aprox. 180 km), there was little genetic differentiation among populations (F ST = 0.0-0.0097 and G ST = 0.005-0.127), without isolation by distance, and high levels of gene flow (Nm ≈ 250). High frequencies of null alleles were found over all loci across populations (Na = 0.292) which seem to explain the significant heterozygote deficiencies found. Approximatelly 98% of the variance was found within individuals and very little at the other hierarchical levels. The high levels of genetic diversity and gene flow detected seem to indicate that the codling moth populations studied in both regions have an almost continuous distrib
Evaluación de la Eficacia, Efecto Residual y de Volteo de Aplicaciones en Pretrasplante de Insecticidas Nicotinoides y Mezclas de Nicotinoide-Piretroide para el Control de Myzus persicae nicotianae (Hemiptera: Aphididae) en Tabaco
Fuentes-Contreras,Eduardo; Basoalto,Esteban; Sandoval,Claudio; Pavez,Patricia; Leal,Claudia; Burgos,Raúl; Mu?oz,Cristián;
Agricultura Técnica , 2007, DOI: 10.4067/S0365-28072007000100002
Abstract: pretransplant applications of imidacloprid, acetamiprid and thiamethoxam, and a mixture of imidacloprid and cyfluthrin were evaluated on tobacco (nicotiana tabacum l.) seedbeds for the control of the aphid myzus persicae nicotianae blackman. corrected mortality at 48 h after aphid release on plants in a seedbed was over 80% almost permanently up to 75 days after application (daa) with a dose of 14 g a.i. m-2 seedbed of imidacloprid. in another experiment, the same level of corrected mortality was maintained by doses of 5.6 g a.i. m-2 seedbed of acetamiprid and 7 g a.i. m-2 seedbed of thiamethoxam up to 50 and 30 daa, respectively. after 30 daa for all the insecticides evaluated in both experiments, corrected mortality at 24 h was lower than at 48 h after aphid release on treated plants, which shows a limited knock down effect of these treatments. finally, in another experiment a mixture of 10.5 and 0.21 g a.i. m-2 seedbed of imidacloprid and cyfluthrin, respectively, showed a good knock down effect, with corrected mortality higher than 80% up to 70 daa at 48 h and without significant differences with corrected mortality at 24 h after aphid release on plants.
Evaluación de la Eficacia, Efecto Residual y de Volteo de Aplicaciones en Pretrasplante de Insecticidas Nicotinoides y Mezclas de Nicotinoide-Piretroide para el Control de Myzus persicae nicotianae (Hemiptera: Aphididae) en Tabaco Evaluation of Efficacy, Residual and Knock Down Effects of Pretransplant Applications of Nicotinoid and Nicotinoid-Pyrethroid Insecticide Mixtures for the Control of Myzus persicae nicotianae (Hemiptera: Aphididae) on tobacco
Eduardo Fuentes-Contreras,Esteban Basoalto,Claudio Sandoval,Patricia Pavez
Agricultura Técnica , 2007,
Abstract: Se evaluaron aplicaciones en pretrasplante en almacigueros de tabaco (Nicotiana tabacum L.) de imidacloprid, acetamiprid y tiametoxam, y una mezcla de imidacloprid y ciflutrina para el control del áfido Myzus persicae nicotianae Blackman. La dosis de imidacloprid de 14 g i.a. m-2 de almaciguero presentó mortalidades corregidas superiores al 80% casi permanentemente hasta los 75 días después de la aplicación (DDA) a las 48 h de la colocación de los áfidos sobre las plantas. En otro experimento acetamiprid en dosis de 5,6 g i.a. m-2 de almaciguero y tiametoxam en dosis de 7 g i.a. m-2 de almaciguero mantuvieron este mismo nivel de mortalidad corregida hasta los 50 y 30 DDA, respectivamente. A partir de los 30 DDA para todos los insecticidas evaluados en ambos experimentos, la mortalidad corregida a las 24 h fue menor que a las 48 h de la colocación de los áfidos sobre las plantas tratadas, lo cual muestra un limitado efecto de volteo de estos tratamientos. Finalmente, en otro experimento la mezcla de imidacloprid con ciflutrina en dosis de 10,5 y 0,21 g i.a. m-2 de almaciguero, respectivamente, presentó un buen efecto de volteo, con mortalidades corregidas superiores al 80% hasta los 70 DDA a las 48 h y sin diferencias significativas con la mortalidad corregida a las 24 h desde la colocación de los áfidos sobre las plantas. Pretransplant applications of imidacloprid, acetamiprid and thiamethoxam, and a mixture of imidacloprid and cyfluthrin were evaluated on tobacco (Nicotiana tabacum L.) seedbeds for the control of the aphid Myzus persicae nicotianae Blackman. Corrected mortality at 48 h after aphid release on plants in a seedbed was over 80% almost permanently up to 75 days after application (DAA) with a dose of 14 g a.i. m-2 seedbed of imidacloprid. In another experiment, the same level of corrected mortality was maintained by doses of 5.6 g a.i. m-2 seedbed of acetamiprid and 7 g a.i. m-2 seedbed of thiamethoxam up to 50 and 30 DAA, respectively. After 30 DAA for all the insecticides evaluated in both experiments, corrected mortality at 24 h was lower than at 48 h after aphid release on treated plants, which shows a limited knock down effect of these treatments. Finally, in another experiment a mixture of 10.5 and 0.21 g a.i. m-2 seedbed of imidacloprid and cyfluthrin, respectively, showed a good knock down effect, with corrected mortality higher than 80% up to 70 DAA at 48 h and without significant differences with corrected mortality at 24 h after aphid release on plants.
Susceptibilidad a Insecticidas y Actividad Enzimática de Cydia pomonella L. (Lepidoptera: Tortricidae) Proveniente de Tres Huertos de la Región del Maule, Chile
Reyes,Maritza; Bouvier,Jean Charles; Boivin,Thomas; Fuentes-Contreras,Eduardo; Sauphanor,Beno?t;
Agricultura Técnica , 2004, DOI: 10.4067/S0365-28072004000300002
Abstract: cydia pomonella l., the major pest of pome fruits and walnuts in chile, has been controlled almost exclusively with applications of organophosphates insecticides. however, during the last few seasons, increasing levels of fruit damage at harvest have been observed. given that this insect has evolved insecticide resistance in several countries, the susceptibility to diagnostic dosages of azinphos methyl and tebufenozide were evaluated on diapausing larvae in populations from three apple orchards in maule region and one susceptible laboratory strain (s); as well as the activity of detoxifying enzymes on adults emerging from the aforementioned. both mixed function oxidases (ofm) and glutathione-s-tranferases (gst) activities were evaluated by fluorometry, while esterase activity (est) was determined by absorption. larval mortality for azinphosmethyl was significantly lower in the populations from molina and teno (30 and 85.4%, respectively) than in the susceptible laboratory strain (95.3%). for tebufenozide larval mortality was significantly lower in the molina strain (35.1%) than the s strain (88.6%). gst activity was statistically higher in two of the three analyzed orchards (13,679 fluorescence insect-1 units in teno, and 13,096 fluorescence insect-1 units in molina). similarly, ofm activity was significantly higher in the same orchards, with values of 25.08 and 17.95 picograms (pg) of 7oh insect-1 min1 in molina and teno, respectively. the s strain had significantly higher est activity in relation to the other populations, which seems to be unrelated with lower susceptibility to the insecticides evaluated.
Differences in the Detoxification Metabolism between Two clonal Lineages of the Aphid Myzus persicae (Sulzer) (Hemiptera: Aphididae) Reared on Tobacco (Nicotiana tabacum L.)
Cabrera-Brandt,Marco A; Fuentes-Contreras,Eduardo; Figueroa,Christian C;
Chilean journal of agricultural research , 2010, DOI: 10.4067/S0718-58392010000400006
Abstract: myzus persicae (sulzer) is a highly polyphagous aphid species, with a subspecies (m. persicae nicotianae) well adapted to tobacco (nicotiana tabacum l.). we evaluated the effect of this host plant on the aphid performance and detoxification enzymes, in order to test the participation of xenobiotic metabolism on the ability of this aphid to overcome the tobacco chemical defences. two genotypes, one corresponding to the only m. persicae nicotianae genotype reported in chile on tobacco, and one genotype belonging to m. persicae sensu stricto were reared on tobacco and pepper (capsicum annuum l.), respectively. m. persicae nicotianae showed a significantly higher intrinsic rate of increase (rm) on pepper than on tobacco, and m. persicae s.s. performed similarly, but with no reproduction at all on tobacco. in order to evaluate the effect of tobacco on detoxification enzymes, esterases, glutathione s-transferases (gst) and cytochrome p-450 monooxygenases (mo) were determined in both selected aphid genotypes after 12, 24, 36, 48 and 72 h of rearing on tobacco and pepper. m. persicae nicotianae exhibited the higher total esterase activities when reared on tobacco than on pepper after 48 h of rearing, while the activities of gst and mo did not show any significant difference between host-plants and duration of treatment. for m. persicae s.s., no significant differences were observed among host-plants for the studied enzymes. these results suggest a participation of the esterases, on the ability of this m. persicae nicotianae to overcome the tobacco defences.
Susceptibilidad a Insecticidas y Actividad Enzimática de Cydia pomonella L. (Lepidoptera: Tortricidae) Proveniente de Tres Huertos de la Región del Maule, Chile Insecticide Susceptibility and Enzymatic Activity of Cydia pomonella L. (Lepidoptera: Tortricidae) from Three Apple Orchards of Maule Region, Chile
Maritza Reyes,Jean Charles Bouvier,Thomas Boivin,Eduardo Fuentes-Contreras
Agricultura Técnica , 2004,
Abstract: Cydia pomonella L., la principal plaga de pomáceas y nogales en Chile, ha sido controlada casi exclusivamente con aplicaciones de insecticidas organofosforados. Sin embargo, durante las últimas temporadas se han observado crecientes niveles de frutos da ados a cosecha. Dado que esta plaga ha desarrollado resistencia a insecticidas en varios países, se evaluó la susceptibilidad a dosis diagnóstico de azinfos metil y tebufenozide de larvas diapausantes provenientes de tres huertos de manzano de la Región del Maule y una cepa susceptible de referencia (S); además de la actividad de enzimas detoxificadoras en adultos emergidos de las mismas Tanto la actividad de oxidasas de función múltiple (OFM) como de glutation-S-transferasas (GST) se evaluó a través de fluorimetría, mientras la de esterasas (EST) se determinó por absorbancia. La mortalidad larvaria frente a azinfos metil fue significativamente menor para Molina y Teno (30 y 85,4%, respectivamente) que para la cepa S (95,3%). Para tebufenozide la mortalidad larvaria fue significativamente menor en Molina (35,31%) que en la cepa S (88,6%). La actividad de GST fue significativamente mayor en dos de los tres huertos analizados (Teno = 13.679 unidades de fluorescencia insecto-1 y Molina =13.096 unidades de fluorescencia insecto-1). Similarmente, la actividad de OFM fue significativamente mayor en los mismos huertos, con valores 25,08 y 17,95 picogramos (pg) de 7OH insecto-1 min.-1 para Molina y Teno, respectivamente. La cepa S presentó una actividad de EST significativamente mayor que la de las otras poblaciones, la cual parece no estar relacionada con la menor susceptibilidad a los insecticidas evaluados. Cydia pomonella L., the major pest of pome fruits and walnuts in Chile, has been controlled almost exclusively with applications of organophosphates insecticides. However, during the last few seasons, increasing levels of fruit damage at harvest have been observed. Given that this insect has evolved insecticide resistance in several countries, the susceptibility to diagnostic dosages of azinphos methyl and tebufenozide were evaluated on diapausing larvae in populations from three apple orchards in Maule Region and one susceptible laboratory strain (S); as well as the activity of detoxifying enzymes on adults emerging from the aforementioned. Both mixed function oxidases (OFM) and glutathione-S-tranferases (GST) activities were evaluated by fluorometry, while esterase activity (EST) was determined by absorption. Larval mortality for azinphosmethyl was significantly lower in the populations from Molina and T
Differences in the Detoxification Metabolism between Two clonal Lineages of the Aphid Myzus persicae (Sulzer) (Hemiptera: Aphididae) Reared on Tobacco (Nicotiana tabacum L.) Diferencias en el Metabolismo de Detoxificación entre dos Linajes Clonales del áfido Myzus persicae (Sulzer) (Hemiptera: Aphididae) creados sobre tabaco (Nicotiana tabacum L.)
Marco A Cabrera-Brandt,Eduardo Fuentes-Contreras,Christian C Figueroa
Chilean Journal of Agricultural Research , 2010,
Abstract: Myzus persicae (Sulzer) is a highly polyphagous aphid species, with a subspecies (M. persicae nicotianae) well adapted to tobacco (Nicotiana tabacum L.). We evaluated the effect of this host plant on the aphid performance and detoxification enzymes, in order to test the participation of xenobiotic metabolism on the ability of this aphid to overcome the tobacco chemical defences. Two genotypes, one corresponding to the only M. persicae nicotianae genotype reported in Chile on tobacco, and one genotype belonging to M. persicae sensu stricto were reared on tobacco and pepper (Capsicum annuum L.), respectively. M. persicae nicotianae showed a significantly higher intrinsic rate of increase (r m) on pepper than on tobacco, and M. persicae s.s. performed similarly, but with no reproduction at all on tobacco. In order to evaluate the effect of tobacco on detoxification enzymes, esterases, glutathione S-transferases (GST) and cytochrome P-450 monooxygenases (MO) were determined in both selected aphid genotypes after 12, 24, 36, 48 and 72 h of rearing on tobacco and pepper. M. persicae nicotianae exhibited the higher total esterase activities when reared on tobacco than on pepper after 48 h of rearing, while the activities of GST and MO did not show any significant difference between host-plants and duration of treatment. For M. persicae s.s., no significant differences were observed among host-plants for the studied enzymes. These results suggest a participation of the esterases, on the ability of this M. persicae nicotianae to overcome the tobacco defences. Myzus persicae (Sulzer) es un áfido polífago que incluye a Myzus persicae nicotianae, una subespecie altamente adaptada sobre tabaco (Nicotiana tabacum L.). Evaluamos el efecto del tabaco sobre el desempe o biológico y sobre determinadas enzimas de detoxificación en áfidos, para estudiar su participación en la capacidad de M. persicae nicotianae de superar las defensas químicas del tabaco. Dos genotipos de M. persicae, uno correspondiente al único genotipo perteneciente a M. persicae nicotianae reportado en Chile sobre tabaco y el otro perteneciente a M. persicae sensu stricto, fueron criados sobre tabaco y pimentón (Capsicum annuum L.), respectivamente. M. persicae nicotianae mostró una tasa intrínseca de crecimiento (r m) significativamente mayor sobre pimentón que sobre tabaco, mientras que M. persicae s.s. no se reprodujo sobre tabaco. Para evaluar los efectos del tabaco sobre el metabolismo de detoxificación, se determinó la actividad de las enzimas esterasas, glutation S-transferasas (GST) y citocromo
EFECTO DE LA DENSIDAD CELULAR DE INOCULACIóN EN EL CRECIMIENTO DE Chlorella vulgaris CLV2 CULTIVADA BAJO CONDICIONES MIXOTRóFICAS
Heberto A. Rodas-Gaitán,Humberto Rodríguez- Fuentes,Gerardo Flores-Mendiola,Juan A. Vidales-Contreras
Revista fitotecnia mexicana , 2012,
Abstract: El uso de microalgas para el aprovechamiento de biomoléculas (proteínas, carbohidratos y lípidos) ha tomado auge en los últimos a os. Entre ellas se encuentra Chlorella vulgaris, microalga unicelular verde motil de forma esférica del Filo Chlorophyta. En este trabajo se evaluaron tres densidades de inoculación de Chlorella vulgaris CLV2 y su efecto en el crecimiento bajo condiciones mixotróficas;los datos se ajustaron a modelos sigmoidales en cada densidad. En el Tratamiento 1 (1 x 106 células mL-1) el mejor modelo tuvo una R2 de 0.85 y un tiempo de generación de 59 h. En el Tratamiento 2 (2 x 106 células mL-1) el mejor modelo tuvo una R2 de 0.89 y un tiempo de generación de 23.5 h. En el Tratamiento 3 (5 x 106 células mL-1) el modelo tuvo una R2 de 0.92 y un tiempo de generación de 7.5 h. El Tratamiento 3 que consistió en la mayor densidad celular de inoculación, presentó el mayor crecimiento y el menor tiempo de generación, porque redujo el tiempo en alcanzar cada fase de crecimiento y sin presencia de microorganismos contaminantes.
Tumores estromales gastrointestinales duodenales: Report of one case
Carvajal H,Carlos; Iturra U,Sebastián; Justiniano P,Juan Carlos; Bustamante Z,Marco; Contreras P,Juan Eduardo; Lombardi S,Juan; Capetillo Fuentes,María;
Revista médica de Chile , 2006, DOI: 10.4067/S0034-98872006000400012
Abstract: gastrointestinal stromal tumors (gist) are lesions whose diagnosis and treatment have varied in the last decade. we report a 76 year-old male with a history of eight episodes of upper gastrointestinal bleeding. a duodenography showed an elevated lesion in the third portion of the duodenum with a central ulceration. it was initially managed with tumorectomy and primary closure of the duodenum. the pathological study of the surgical specimen revealed a low grade gastrointestinal stromal tumor. three years later, the tumor recurred and pancreatoduodenectomy was performed. due to the high risk of malignant potential, tumor size, number of mitoses and the presence of necrosis, imatinib mesylate was started. the patient had a satisfactory evolution, without evidences of recurrence after 15 months of follow up
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