127 research outputs found

    Microbiome of a suppressive agricultural amended soil

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    The application of organic amendments to the soil is a strategy that cause the improvement of avocado agricultural soils. This strategy is included in the integrated management of avocado white root rot, caused by the phytopathogenic fungus Rosellinia necatrix in the Mediterranean area. In this study, we evaluate the suppressive capacity of an agricultural soil amended with composted almond shells and the role of its microbiome. The application of composted almond shells as organic amendment increase the suppressive activity of field soil against the pathogen, and this suppressiveness can be associated to the microbiota present in amended soil. Soil suppressivity is reduced when soil was heat treated, and then recovered when the heat-treated soil was partially complemented with field soil. Accordingly, we characterized the microbial community of amended suppressive soil by sequencing the 16S rRNA gene and ITS regions. This analysis showed the microbiome structure of the suppressive amended soil. The comparison among this community with the microbial community of an unamended soil reveals subtle differences in the structure of the microbiome. Specifically found in amended soil, we observed a high relative abundance of different classes of bacteria as Gammaprotobacteria and Betaproteobacteria (Proteobacteria), Acidimicrobiia (Actinobacteria) and Solibacteres (Acidobacteria). Regarding fungal communities, we observed a high relative abundance of some classes as Dothideomycetes, Lecanoromycetes (Ascomycota) and Tremellomycetes (Basidiomycota). Furthermore, we performed a functional analysis of the suppressive microbiome to understand the potential activities involved in suppressiveness. The use of a comercial microarray (GeoChip) with more than 80000 different probes, showed the significant increase in amended soil of carbon cycle genes, specifically genes of degradation routes of different carbon sources, as well as the significant reduction of virulence, metal resistance or aromatic compounds degradation related genes. By this analysis, we observed unique detected genes belonging to microorgnisms involved in biological control as Gammaproteobacterias, Firmicutes or Dothideomycetes. The role of these subtle changes as final responsible of the induced suppressiveness in agricultural amended soils is discussed.Universidad de Málaga, Campus de Excelencia Internacional Andalucía Tech. AGL2014-52518-C2-1-

    Analysis of the microbial community of a suppressive soil from an avocado crop

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    Taking together our results, we showed the positive effect of application of composted almond shells as organic amendment in biological control of avocado soil-borne pathogen Rosellinia necatrix. In this work, we assigned this biocontrol activity to soil microbial community, where different groups of Gammaproteobacteria, including Pseudomonas spp., were naturally selected. Isolation of culturable members from the suppressive soil of Pseudomonas spp., Serratia spp. and Stenotrophomonas spp., showed the ability of these microorganisms to control the disease index cause by the pathogen, both in avocado roots as in wheat root, using different biological control methods. Due to the importance of genus Pseudomonas sp. in this suppressive soil, and using Pseudomonas spp. previously described by their biocontrol activity against R. necatrix, we design a bacterial consortium in order to improve the knowledge of the putative community interactions that occur during biological control process

    Microbial profiling of a suppressiveness-induced agricultural soil amended with composted almond shells lead to isolation of new biocontrol agents

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    Vida et al., 2016. Microbial profiling of a suppressiveness-induced agricultural soil amended with composted almond shells lead to isolation of new biocontrol agents. Biological and integrated control of plant pathogens IOBC-WPRS Bulletin Vol. 117, 2016 pp. 140-143This study focused on the microbial profile present in an agricultural soil that becomes suppressive after the application of composted almond shells (AS) as organic amendments. The role of microbes in the suppression of Rosellinia necatrix, the causative agent of avocado white root rot, was determined after heat-treatment and complementation experiments with different types of soil. Bacterial and fungal profiles based on the 16S rRNA gene and ITS sequencing, the soil under the influence of composted almond shells revealed an increase in Proteobacteria and Ascomycota groups, as well as a reduction in Acidobacteria and Xylariales (where R. necatrix is allocated). Complementary to these findings, functional analysis by GeoChip 4.6 confirmed the improvement of a group of specific probes included in the “soil benefit” category was present only in AS-amended soils, corresponding to specific microorganisms previously described as potential biocontrol agents, such as Pseudomonas spp., Burkholderia spp. or Actinobacteria. Based in such data, a model for the microbial-based suppressiveness is proposed and further isolation of representative microorganisms were performed.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Innovación interactiva docente aplicada en la asignatura Instituciones Básicas de Derecho Privado del primer curso del Grado de Administración y Dirección de Empresas

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    En el contexto y desarrollo del Programa de Formación e Innovación del Profesorado de la Universidad de Sevilla realizado en el Curso 2017/2018 se han aplicado en la Asignatura de Instituciones Básicas de Derecho Privado de los alumnos de primer Curso del Grado en Administración y Dirección de Empresas un Modelo Didáctico personal en base a los principios que los sustentan y que se expondrán en la presente Comunicación, llevándolo al campo práctico con la aplicación de dos Ciclos de Mejora en las clases donde se ha impartido la Asignatura referida. El impulso del mismo se ha producido con las metodologías de clase, el tratamiento previo de los contenidos y la evaluación y calificación de los resultados finalmente obtenidos. Se han abordado los conocimientos y modelos mentales de los estudiantes, sus capacidades y aptitudes

    Deciphering the suppressive soil microbiota from an avocado crop

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    Comunicación en pósterDifferent strategies based on ecological principles have been approached in sustainable agriculture causing positive effects, including the induction of soil suppressiveness against a wide range of soilborne pathogens. Suppressiveness against the phytopathogenic fungus Rosellinia necatrix was observed after the application of composted almond shells in avocado crops. Previous works have analyzed the use of this traditional strategy and applied new microbial community analysis techniques in order to help in the identification of targeted sustainable agricultural strategies. These studies have focused on the microbial profile from an induced-suppressive soil where the soil microbiome had a proven essential role. Microbial profiles based on the 16S rRNA gene and ITS regions sequencing were analysed and an increase in Gammaproteobacteria and Dothideomycetes groups, as well as a reduction in Xylariales (where R. necatrix is allocated) were observed. These results led to the bacterial isolation of different groups of Gammaproteobacteria from this suppressive soil in order to identify new strains with biological control properties. Different characterization tests were performed, and a final selection of representative strains belonging to the genus Pseudomonas and related groups showed, all of them, plant disease protection abilities. Moreover, using previously described biological control agents against R. necatrix, a bacterial synthetic community have been design in order to improve the knowledge of the multitrophic interactions that occur during biological control process.This work was supported by Plan Nacional I+D+I (MINECO, Spain) (AGL2014-52518-C2-IR) and co-financed by FEDER funds (EU). C.Vida was supported by a PhD fellowship from the FPI program of MINECO. Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Isolation, characterization and selection of Pseudomonas spp. as biological control agents from a suppressive soil

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    Bacterial profile from a suppressive soil against Rosellinia necatrix, fungal pathogen of avocado roots, were obtained by 16S rRNA gene sequencing. The results revealed a significant increase in the bacterial class of Gammaproteobacteria, especially in some antagonistic representatives of Pseudomonas spp. For this reason, a collection of 246 bacterial isolates was obtained from this suppressive soil in order to identify new strains with antifungal activity against this fungal phytopathogen. First, we performed an isolation on a selective medium for Pseudomonas-like microorganisms. Then, we used different characterization tests in order to analyse the bacterial collection, including the identification of the general metabolic profile of glucose, the profiling of antifungals produced, both the putative production of antifungal compounds and lytic exoenzymes, as well as the evaluation of traits related with beneficial effects on plants. A final selection of representative strains resulted in antifungal isolates belonging to the genus Pseudomonas and related groups. These selected strains were tested for plant protection by an in vivo experiment using avocado and wheat plants challenged by the pathogen R. necatrix, showing all of them an antifungal ability and plant disease protection.This work was supported by Plan Nacional I+D+I from MINECO (Spain) (AGL2014-52518-C2-IR) and co-financed by FEDER funds (EU). C.Vida was supported by a PhD fellowship from the FPI program of MINECO.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Isolation, characterization and selection of bacterial isolates from a suppressive soil with beneficial traits to plants

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    Backgrounds This study focused on the characterization and selection of bacterial strains obtained from a suppressive soil displaying antifungal activity against the soilborne phytopathogenic fungi Rosellinia necatrix. Bacterial profile from this suppressive soil were first obtained by 16S rRNA gene sequencing, revealing a significant increase in the bacterial class Gammaproteobacteria, especially in some antagonistic representatives of Pseudomonas spp. Objectives To obtain and characterize a collection of 246 bacterial isolates obtained from this suppressive soil, in order to identify new strains with antifungal activity against fungal phytopathogens. Methods To obtain the bacterial collection, we performed an isolation on a selective medium for Pseudomonas-like microorganisms. Further characterization tests were used in order to analyse the bacterial collection, including identification of the general metabolic profile of glucose, the profiling of antifungals produced, including both the putative production of antifungal compounds and lytic exoenzymes, and the evaluation of traits related with beneficial effects on plants. Conclusions A final selection of representative strains resulted in antifungal isolates belonging to the genus Pseudomonas, but also some representatives of the genera Serratia and Stenotrophomonas. These selected strains were tested for plant protection by an in vivo experiment using avocado and wheat plants challenged by the pathogen R. necatrix, showing all of them an antifungal ability and plant disease protection. Pseudomonas-like strains isolated from suppressive soils constitute an excellent source for novel microbial biocontrol agents against soilborne fungal pathogens. This work was supported by grant AGL2014-52518-C2-1-R. Carmen Vida and Sandra Tienda are supported by a PhD fellowship from the FPI program of the Spanish Government.This work was supported by grant AGL2014-52518-C2-1-R. Carmen Vida and Sandra Tienda are supported by a PhD fellowship from the FPI program of the Spanish Government; Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Violencia intrafamiliar como factor de riesgo para complicaciones obstetricas mas frecuentes en mujeres atendidas en el Hospital Bertha Calderon Roque durante el periodo Abril 2013-Abril 2014

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    La violencia intrafamiliar es un problema social de grandes dimensiones que afecta sistemáticamente a importantes sectores de la población, especialmente a mujeres, niñas, niños y ancianos. Sin embargo, esta violencia tiene direccionalidad clara en la mayoría de los casos. La violencia es ejercida por hombres contra mujeres y niñas. La forma más endémica de la violencia intrafamiliar es el abuso de las mujeres por el compañero íntimo. La situación en Nicaragua en los últimos años se ha caracterizado por diversos acontecimientos políticos, económicos y sociales. En donde los conceptos de dignidad y derechos humanos, pierden su importancia cuando se refiere a situaciones de maltrato en la relación de pareja (violencia conyugal). Esta problemática se ha venido reproduciendo de generación en generación a lo largo de los años a través de diversos medios (la educación, la cultura, la religión, etc.). Estos medios ayudan a que la ideología dominante en nuestra sociedad se permita, justifique, e incluso aliente las agresiones del hombre contra la mujer y viceversa. Este problema está entre nosotros. Se le impide salir a la luz pública, aunque lentamente comienzan a correrse las gruesas cortinas de los mitos y los prejuicios que lo ocultan. La violencia y el maltrato dentro de la familia no es un fenómeno aislado, como durante tanto tiempo nos empeñamos a creer. Diversos estudios estadísticos desafían nuestra incredulidad: así tenemos que alrededor del 50% de las familias sufre o ha sufrido algunas de las formas de violenci

    Antioxidant and Antimicrobial Activity of Hydroethanolic Leaf Extracts from Six Mediterranean Olive Cultivars

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    Phenolic profiles, antioxidant, and antimicrobial activities of hydroethanolic olive leaf extracts from six Mediterranean olive cultivars (Croatian: Lastovka, Levantinka, Oblica; Italian: Moraiolo, Frantoio, Nostrana di Brisighella) were investigated. As expected, various distributions of phenolic levels were observed for each cultivar and the total phenolic content showed high variability (ranging from 4 to 22 mg GAE/g of dry extract), with the highest amount of phenolics found in the Oblica sample, which also provided the highest antiradical (ORAC) and reducing activity (FRAP). The screening of individual compounds was performed by HPLC-PDA-ESI-QTOF-MS and the main detected compounds were oleuropein, hydroxytyrosol, oleoside/secologanoside, verbascoside, rutin, luteolin glucoside, hydroxyoleuropein, and ligstroside. While the antioxidant activity of the samples was relatively high, they showed no bactericidal and bacteriostatic activity against E. coli and S. Typhimurium; weak activity against Staphylococcus aureus, Bacillus cereus, and Listeria innocua; and inhibitory effects against Campylobacter jejuni at 0.5 mg dry extract/mL. The obtained results support the fact that olive leaf extracts, and especially those from the Oblica cultivar, could potentially be applied in various industries as natural preservatives and effective and inexpensive sources of valuable antioxidants.PRIMA program under project BioProMedFood 1467European CommissionMCIN/AEI RTI2018-099835-A-I0
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