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Search Results: 1 - 10 of 5805 matches for " Sonia Villegas "
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RESPUESTA DE DIFERENTES POBLACIONES DE Spongospora subterranea f. sp. subterranea A LA ROTACIóN ENTRE DOS VARIEDADES DE PAPA (Solanum tuberosum ssp. andigena)
Jaramillo Villegas,Sonia; Botero Herrera,Juan Manuel;
Revista Facultad Nacional de Agronomía, Medellín , 2007,
Abstract: in antioquia colombia were realized three experiments with potatoes, to know the behavior of the ica puracé cultivar, considered by agricultures as powder scab resistant, and the diacol capiro cultivar, which is highly susceptible. it is pretended to evaluate if there is a rotation effect, of the two varieties and different populations of spongospora subterranea f. sp. subterranea on the powder scab. cistosori (spore balls) was extracted from 23 populations of s. subterranea extracted from pustules in tubers surface or galls in roots from different varieties, from potato regions of colombia . the incidence and severity degree of these populations was evaluated under the process of the ica puracé-diacol capiro rotation and viceversa, in three successive harvests, under the mesh house conditions. it was observed that the different pathogen populations did not affect the weight, neither caused powder scab symptoms in the tubers, although presented different severity levels on the roots of two varieties) with unpredictable tendency during the different harvests, with low level (> 0 to 2), medium (>2 to 6) and high (>6) symptoms, being more susceptible the diacol capiro, which apparently incremented the infection in the soil. the ica puracé was low level affected by few population (7/23) with the powder scab, during the first cycle and possibly presented a suppressive effect over the powdery scab for the diacol capiro rotation in the second harvest, and then, a rising in the galls of both varieties during the third harvest, in the pots where originally planted, because of a possible increasing of cistosori in the soil. the initial rotation reduces the powder scab symptoms (second harvest) in diacol capiro, but the ica puracé cultivar is more affected trough the generations where diacol capiro was growing.
RESPUESTA DE DIFERENTES POBLACIONES DE Spongospora subterranea f. sp. subterranea A LA ROTACIóN ENTRE DOS VARIEDADES DE PAPA (Solanum tuberosum ssp. andigena) RESPONSE OF DIFFERENT POPULATIONS OF Spongospora subterranea f .sp. subterranea TO ROTATION OF TWO POTATO CULTIVARS (Solanum tuberosum ssp. andigena)
Sonia Jaramillo Villegas,Juan Manuel Botero Herrera
Revista Facultad Nacional de Agronomía, Medellín , 2007,
Abstract: En una zona papera del Oriente de Antioquia - Colombia, se realizaron tres experimentos, para conocer el comportamiento de las variedades ICA Puracé, considerada por los agricultores, como resistente a la sarna polvosa de la papa, y la variedad Diacol Capiro susceptible. Se pretendió evaluar si hay un efecto de la rotación, entre las dos variedades con diferentes poblaciones de Spongospora subterranea f sp. subterranea sobre la sarna polvosa. Se utilizaron quistosoros de 23 poblaciones de S. subterranea, extraídos de pústulas presentes en tubérculos o agallas en raíces de diferentes variedades, y procedentes de las regiones más productoras de papa en el país. Se determinó la incidencia y el grado de severidad de dichas poblaciones bajo el proceso de rotación entre ICA Puracé-Diacol Capiro y viceversa, en tres cosechas sucesivas, en condiciones de casa de malla. Se observó que las poblaciones del patógeno, no afectaron el peso, ni causaron síntomas de sarna polvosa en los tubérculos, pero si en las raíces, con diferentes grados de severidad en las dos variedades, con tendencia poco predecible en las distintas cosechas, con niveles bajo (> 0 a 2), medio (> 2 a 6) y alto (>6), siendo mas susceptible la Diacol Capiro, que al parecer favoreció el incremento del inóculo. Diacol Capiro, presentó alta incidencia (23/23) y severidad (algunas poblaciones con grado >6) en el primer ciclo, mientras que la ICA Puracé fue levemente afectada por pocas poblaciones (7/23) de S. subterranea y posiblemente presentó efecto supresivo sobre los quistosoros en el suelo en la rotación (segundo ciclo), puesto que se redujo el grado de severidad (<2) para Diacol Capiro, pero en el tercer ciclo (segunda rotación), se aumentó la severidad para ambas variedades. La rotación por un ciclo entre ambas variedades parece reducir la severidad de los síntomas de la sarna polvosa, pero para la tercera cosecha ambas variedades aumentaron su incidencia y severidad. La variedad ICA Puracé aumentó el grado de severidad y la incidencia, a medida que pasaron las generaciones con Diacol Capiro, pero en ésta se redujo el grado de severidad, por posible efecto de la rotación. In Antioquia Colombia were realized three experiments with potatoes, to know the behavior of the ICA Puracé cultivar, considered by agricultures as powder scab resistant, and the Diacol Capiro cultivar, which is highly susceptible. It is pretended to evaluate if there is a rotation effect, of the two varieties and different populations of Spongospora subterranea f. sp. subterranea on the powder scab. Cistosori (spore balls) was
EFECTO SOBRE LA SARNA POLVOSA DE CUATRO AISLAMIENTOS DEL HONGO Trichoderma asperellum EN TRES TIPOS DE SUELO
Gilchrist,Elizabeth; Jaramillo Villegas,Sonia; Reynaldi,Sebastián;
Revista Facultad Nacional de Agronomía, Medellín , 2009,
Abstract: the protozoan spongospora subterranea f. sp. subterranea is an obligate parasite that replicates in roots and tubers of potato causing the powdery scab. this disease has disseminated on a global scale, because the commercial traffic of infected tubers used as seed and the absence of effective treatments. the present work investigated the effects of four isolates of trichoderma asperellum in three soil types: andisol, entisol and inceptisol. the soils were infected with 1942 ± 226 cystosori per gram of soil. it was used solanum tuberosum variety diacol capiro. no differences were observed between treated and non treated plants with t. asperellum. the root surface affected by galls was an average of 2.2 %, and no significant differences (p<0.05) were observed among the soils. the reduction of plant growth was of 41, 32 and 28 % for the andisol, entisol and inceptisol, respectively. the reduction in tubers production was of 40, 28 and 0,1% for the andisol, entisol and inceptisol, respectively. similar percent of root surface covered with galls resulted in production reduction of 40%, but also of 0,1%, indicating the necessity of other methods to determine the infection severity. the growth and production reductions were inversely associated with the al3+ concentration in the soils, suggesting that powdery scab effects are strongly related to soil characteristics.
Rescate y germinación in vitro de embriones inmaduros de cedro negro (Juglans neotropica Diels)
Quintero García Oscar Darío,Jaramillo Villegas Sonia
Acta Agronómica , 2012,
Abstract: Embriones inmaduros de cedro negro (Juglans neotropica) (Juglandaceae) con 16 y 20 semanas de desarrollo fueron removidos asépticamente de los frutos y sembrados durante 60 días en los medios de culti+o M- (Muras3ige 4 -koog, 99<=), WPM (Blo4d 4 McCoFn, 9980) 4 GHW (Gri+er 4 Huni4uki, 9984), sin reguladores de crecimiento. -e obser+ó que embriones con 9< semanas de desarrollo no germinaron en los tres medios de cultivo; por el contrario, los embriones con 20 semanas de desarrollo presentaron una germinación de 100%. Se encontró un marcado efecto del medio en el crecimiento de los embriones, siendo el medio M- meOor (P P 0.05) que los medios GHW 4 WPM, debido a que en él los embriones Wresentaron ma4or altura 4 WroWorción talloXraiY Wara la obtención de WlZntulas comWletas
EFECTO SOBRE LA SARNA POLVOSA DE CUATRO AISLAMIENTOS DEL HONGO Trichoderma asperellum EN TRES TIPOS DE SUELO EFFECT ON THE POWDERY SCAB OF FOUR ISOLATES OF THE FUNGUS Trichoderma asperellum IN THREE TYPES OF SOILS
Elizabeth Gilchrist,Sonia Jaramillo Villegas,Sebastián Reynaldi
Revista Facultad Nacional de Agronomía, Medellín , 2009,
Abstract: El protozoario Spongospora subterranea f. sp. subterranea es un parásito obligado que replica en raíces y tubérculos de papa causando la sarna polvosa. Esta enfermedad se ha difundido a escala global debido al comercio de tubérculos-semilla infectados y a la ausencia de tratamientos efectivos. En este trabajo se investigó la influencia sobre la sarna polvosa de cuatro aislamientos de Trichoderma asperellum en tres tipos de suelo: Andisol, Entisol e Inceptisol. Tubérculos de Solanum tuberosum variedad Diacol Capiro fueron plantados en parcelas infectadas con 1942 ± 226 quistosoros por gramo de suelo. No se observaron diferencias entre las plantas tratadas y no tratadas con T. asperellum. La superficie de raíz ocupada por agallas fue en promedio 2,2%, sin encontrarse diferencias significativas (P<0,05) entre los tipos de suelos. La reducción del crecimiento de las plantas fue de 41, 32 y 28% en el Andisol, el Entisol y el Inceptisol, respectivamente. La reducción de la producción fue de 40, 28 y 0,1 % en el Andisol, el Entisol y el Inceptisol, respectivamente. Un porcentaje similar de superficie de raíz cubierto por agallas resultó en reducciones de la producción tan disímiles como 40% o 0,1%, indicando necesidad de utilizar otros métodos para determinar la severidad de infección. La reducción del crecimiento y la producción estuvieron inversamente asociadas a la concentración de Al3+ en los suelos, sugiriendo que los efectos de la sarna polvosa están fuertemente relacionados con las condiciones del suelo. The protozoan Spongospora subterranea f. sp. subterranea is an obligate parasite that replicates in roots and tubers of potato causing the powdery scab. This disease has disseminated on a global scale, because the commercial traffic of infected tubers used as seed and the absence of effective treatments. The present work investigated the effects of four isolates of Trichoderma asperellum in three soil types: Andisol, Entisol and Inceptisol. The soils were infected with 1942 ± 226 cystosori per gram of soil. It was used Solanum tuberosum variety Diacol Capiro. No differences were observed between treated and non treated plants with T. asperellum. The root surface affected by galls was an average of 2.2 %, and no significant differences (p<0.05) were observed among the soils. The reduction of plant growth was of 41, 32 and 28 % for the Andisol, Entisol and Inceptisol, respectively. The reduction in tubers production was of 40, 28 and 0,1% for the Andisol, Entisol and Inceptisol, respectively. Similar percent of root surface covered with galls resulted in
EVALUACIóN DE Trichoderma asperellum COMO BIORREGULADOR DE Spongospora subterranea f. sp. subterranea
Hoyos Carvajal,Liliana María; Jaramillo Villegas,Sonia; Orduz Peralta,Sergio;
Revista Facultad Nacional de Agronomía, Medellín , 2008,
Abstract: powdery scab caused by spongospora subterranea, is one of the main diseases on potato crops, is a protozoo for which exist limited control strategies because it counts with diverse types of inoculum, resistance structures and alternative hosts. the objective of this work was to test trichoderma asperellum t-84 and t-109 against s. subterranea under controlled conditions in two experiments, evaluating in plants until nine and twelve week, variables of fresh and dry weight and number of galls produced by the pathogen. consistently the plants with t. asperellum increased fresh weight (experiment 1) and dry weight (experiment 2) and reduced the number of nodules of s. subterranea in potato root, better in single applications than in mixture. this is a preliminary study that suggests t. asperellum could be a potential agent of biological regulation in the future for powdery scab, but it will be require studies of the interaction potato plant/s. subterranea/trichoderma for its implementation.
INFLUENCIA DE LAS CONDICIONES DE INCUBACIóN SOBRE LA ACTIVACIóN DE ZOOSPORAS DE Spongospora subterranea, EN BUSCA DE UN INóCULO PARA EL ESTUDIO DE LA SARNA POLVOSA
Beltrán Sánchez,Edgar; Gilchrist Ramelli,Elizabeth; Jaramillo Villegas,Sonia del Carmen; Reynaldi,Sebastián;
Revista Facultad Nacional de Agronomía, Medellín , 2009,
Abstract: the powdery scab is a disease that decreases potato production. it is caused by spongospora subterranea f. sp. subterranea. this obligate parasite produces cystosori, which are groups of encysted zoospores. when these zoospores are active, they can infect roots and tubers initiating a new replication cycle. to investigate the influence of the incubation conditions on the zoospore activation, suspensions of cystosori in water were incubated under different conditions. the cystosori and the active zoospores were daily counted under microscope. the higher number of active zoospores was found after four days of incubation, meanwhile the lower number of cystosori was found after five days of incubation. this suggests that zoospores are active for a short period. the number of active zoospores per cystosorus was significantly (p<0.05) higher in tap water than in distillated water, and in presence of light than in dark. more zoospores per cystosorus were activated at 19 °c than at 5 °c, but potato roots did not have a significant (p<0.05) effect on zoospores activation. these results indicate that the incubation conditions may increase the zoospores activation. however, the number of active zoospores per cystosori was not higher than five. more active zoospores were expected, because a cystosorus is between 10 and 40 times bigger than a zoospore. this shows that a large number of cystosori are needed to ensure the presence of active zoospores in an inoculum
EFECTO DE DOS MICROORGANISMOS Y UN CONSORCIO DE MICORRIZAS EN COMBINACIóN CON VIRUTA DE PINO SOBRE EL CONTROL DE SARNA POLVOSA (Spongospora subterránea) EN PAPA
Restrepo Duque,Andrés Felipe; Jaramillo Villegas,Sonia; Cotes Torres,José Miguel;
Revista Facultad Nacional de Agronomía, Medellín , 2009,
Abstract: the effect of two potential microorganism, mycorhize and pine wood shavings for management of spongospora subterranea f. sp. subterranea in potato cultivar diacol capiro were evaluated. this research was established at the agricultural center of paysandú (santa elena - medellín) to 2,550 masl, average temperature of 14 oc and average annual rainfall of 2,500 mm. a field experiment was established using a randomized complete design with four replications and five treatments (trichoderma harzianum; comercial product of mycorhize ?mikorhyze lote c7?; pseudomonas fluorescents, pine wood shavings and check without control). were found rates of disease incidence in roots (32%) for the check treatment (without any application), although the severity of disease of both the check and another treatments were very low, which did not exceed 0.23%. the expression of symptoms in tubers showed statistically significant difference between check treatment and another treatment and the use of t. harzianum, mycorhize and p. fluorescents to tubers, like the addition of pine wood shavings on the floor. these treatments reduced the incidence and severity of powdery scab in roots and tubers. the physiological variables dry weight of roots, tubers and leaf, did not show positive increases or significant differences between treatments evaluated.
METODOLOGíA DE EVALUACIóN DE LA SENSIBILIDAD A FUNGICIDAS QoI - FENAMIDONE: CASO DE ESTUDIO Phytophthora infestans (Mont.) de Bary
Escudero Ramírez,Mariana; Marín Montoya,Mauricio; Jaramillo Villegas,Sonia; Cotes Torres,José Miguel;
Revista Facultad Nacional de Agronomía, Medellín , 2009,
Abstract: this study was proposed with the aim to establish in colombia a standard methodology to evaluate the level of sensitivity of fungi and oomycetes to qoi fungicides. the used model was the causal agent of late blight of potato phytophthora infestans and the fungicide fenamidone, an imidazolinone recently introduced in the world market. the methodology included inoculation of leaf discs with a suspension of pathogen's sporangia, evaluation of five doses of fungicide applied as active ingredient and commercial formulation, two techniques of application, statistical analysis using the probit model and a molecular test based on sequencing the cytochrome b gene. this molecular test could be used both before or afterwards the biological evaluation, according to the availability of a supporting laboratory. we hope that this study can stimulate a continuous monitoring of the sensitivity level to qoi of populations of plant pathogens in colombia.
VARIACIóN MORFOLóGICA DE QUISTOSOROS DE Spongospora subterranea (Wallr.) Lagerh f. sp. subterranea.
Jaramillo Villegas,Sonia; Pérez Avenda?o,Gustavo Alberto; Hoyos Carvajal,Liliana María;
Revista Facultad Nacional de Agronomía, Medellín , 2008,
Abstract: powdery scab caused by spongospora subterranea f. sp. subterranea is one of the main pathogens on potato, by losses that cause to produce galls on roots and/or pustules tuber, turning the product no apt to market, beside its high survival underground per prolonged periods of time on soil. the study of variability of s. subterranea is incipient and not yet well understood, neither its biology and methods of control in field. in the following observations morphologic characteristics of some populations of a mixture of cystosorus taken from pustules of tuber or root galls infected with s. subterranea f. sp. subterranea from cundinamarca, antioquia, boyacá and nari?o, main producing zones of potato in colombia, and were performed comparisons with the observations of other authors in europe and asia. these assessments were carried out by means of the measurements of cystosorus of the pathogen with light and electronic microscopy. the results allowed to determine the ranks of size of the colombian populations, which that are between 20 and 45 μm, indifferently of their geographic origin, but with so minor size for those from root galls compared with cystosorus from tuber. both presented minor dimension that the reported by other authors for europe and asia. details of ornamentation and morphology of colombian populations, differ from the european populations, suggesting some degree of difference or variability between the populations of these localities.
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