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Nowadays, fertilization and pest control are carried out using chemical compounds that contaminate soil and deteriorate human health. Plant growth promoting bacteria endophytes (PGPBEs), are a well-studied group of bacteria that offers benefits to the host plant, such as phytostimulation, biofertilization, and protection against other microorganisms. The study of Gluconacetobacter diazotrophicus–which belongs to PGPBEs-aids the development of alternative strategies of an integrated approach for crop management practices. Ralstonia solanacearum is responsible for bacterial wilt disease. This phytopathogen is of great interest worldwide due to the enormous economic losses it causes. In this study the action of G. diazotrophicus as a growth promoting bacterium in Arabidopsis thaliana seedlings is analyzed, evaluating the antagonistic mechanisms of this beneficial endophytic bacterium during biotic stress produced by R. solanacearum. Effective colonization of G. diazotrophicus was determined through bacterial counting assays, evaluation of anatomical and growth parameters, and pigments quantification. Biocontrol assays were carried out with Ralstonia pseudosolanacearum GMI1000 model strain and R. solanacearum A21 a recently isolated strain. Inoculation of A. thaliana (Col 0) with G. diazotrophicus Pal 5 triggers a set of biochemical and structural changes in roots, stems, and leaves of seedlings. Discrete callose deposits as papillae were observed at specific sites of root hairs, trichomes, and leaf tissue. Upon R. pseudosolanacearum GMI1000 infection, endophyte-treated plants demonstrated being induced for defense through an augmented callose deposition at root hairs and leaves compared with the non-endophyte-treated controls. The endophytic bacterium appears to be able to prime callose response. Roots and stems cross sections showed that integrity of all tissues was preserved in endophyte-treated plants infected with R. solanacearum A21. The mechanisms of resistance elicited by the plant after inoculation with the endophyte would be greater lignification and sclerosis in tissues and reinforcement of the cell wall through the deposition of callose. As a consequence of this priming in plant defense response, viable phytopathogenic bacteria counting were considerably fewer in endophyte-inoculated plants than in not-inoculated controls. Our results indicate that G. diazotrophicus colonizes A. thaliana plants performing a protective role against the phytopathogenic bacterium R. solanacearum promoting the activation of plant defense system.

El objetivo de este estudio fue determinar los niveles de resiliencia con sus dos dimensiones, “Aceptación de uno mismo y de la vida” (AUM) y “Competencia Personal” (CP),en participantes de deportes de carácter individual y colectivo. Se realizaron comparaciones inter e intragrupo y en función del nivel competitivo y sexo. Un total de 435 deportistas (300 hombres y 135 mujeres) cumplimentaron un cuestionario socio-demográfico y La Escala de Resiliencia (Wagnild y Young, 1993). Los resultados señalan que quienes practican deportes de carácter individual obtienen valores medios de resiliencia y de la dimensión CP superiores a los obtenidos por deportistas que lo hacen de forma colectiva (p

El reflujo faringolaríngeo. Se origina por el flujo retrógrado de contenido gástrico hacia la faringe, pero existen factores, capaces de perpetuarlo: disfunción del esfínter esofágico, tiempo de exposición y sensibilidad del tejido al material refluido, estos elementos permiten considerar al reflujo faringolaríngeo como una entidad diferente del reflujo gastroesofágico.

This paper presents the process required to implement a data driven Predictive Maintenance (PdM) not only in the machine decision making, but also in data acquisition and processing. A short review of the different approaches and techniques in maintenance is given. The main contribution of this paper is a solution for the predictive maintenance problem in a real machining process. Several steps are needed to reach the solution, which are carefully explained. The obtained results show that the Preventive Maintenance (PM), which was carried out in a real machining process, could be changed into a PdM approach. A decision making application was developed to provide a visual analysis of the Remaining Useful Life (RUL) of the machining tool. This work is a proof of concept of the methodology presented in one process, but replicable for most of the process for serial productions of pieces.

Crop yield reduction due to salinity is a growing agronomical concern in many regions. Increased production of reactive oxygen species (ROS) in plant cells accompanies many abiotic stresses including salinity, acting as toxic and signaling molecules during plant stress responses. While ROS are generated in various cellular compartments, chloroplasts represent a main source in the light, and plastid ROS synthesis and/or elimination have been manipulated to improve stress tolerance. Transgenic tobacco plants expressing a plastid-targeted cyanobacterial flavodoxin, a flavoprotein that prevents ROS accumulation specifically in chloroplasts, displayed increased tolerance to many environmental stresses, including drought, excess irradiation, extreme temperatures and iron starvation. Surprisingly, flavodoxin expression failed to protect transgenic plants against NaCl toxicity. However, when high salt was directly applied to leaf discs, flavodoxin did increase tolerance, as reflected by preservation of chlorophylls, carotenoids and photosynthetic activities. Flavodoxin decreased salt-dependent ROS accumulation in leaf tissue from discs and whole plants, but this decline did not improve tolerance at the whole plant level. NaCl accumulation in roots, as well as increased osmotic pressure and salt-induced root damage, were not prevented by flavodoxin expression. The results indicate that ROS formed in chloroplasts have a marginal effect on plant responses during salt stress, and that sensitive targets are present in roots which are not protected by flavodoxin.

Cortadi, Adriana; Lourdes Pulido García; Martha A. Gattuso; Susana J. Gattuso. 2014. “Morfología y anatomía de nectarios extraflorales en tres especies de las Flacourtiaceae (Salicaceae sensu lato)”. Lilloa 51 (2). En el presente trabajo se estudiaron caracteres morfológicos y anatómicos de los nectarios extraflorales (NEF) en tres especies de Flacourtiaceae: Banara arguta Briq., Banara umbraticola Arechav. y Xylosma venosa N.E. Br., presentes en la provincia de Santa Fe (Argentina). El objetivo del trabajo fue establecer diferencias morfológicas, anatómicas, y de distribución entre los NEF y evaluar su importancia como carácter taxonómico dentro de la familia. En las tres especies estudiadas se estableció la presencia de NEF en diferentes posiciones del limbo foliar (dientes, crenas, ápice foliar) mientras que en el ápice de los pecíolos, los NEF se encontraron solamente en B. arguta y en X. venosa. Anatómicamente los NEF son similares. Se presenta una clave que permite diferenciar a las especies

Pathogens interaction with a host plant starts a set of immune responses that result in complex changes in gene expression and plant physiology. Light is an important modulator of plant defense response and recent studies have evidenced the novel influence of this environmental stimulus in the virulence of several bacterial pathogens. Xanthomonas citri subsp. citri is the bacterium responsible for citrus canker disease, which affects most citrus cultivars. The ability of this bacterium to colonize host plants is influenced by bacterial blue-light sensing through a LOV-domain protein and disease symptoms are considerably altered upon deletion of this protein. In this work we aimed to unravel the role of this photoreceptor during the bacterial counteraction of plant immune responses leading to citrus canker development. We performed a transcriptomic analysis in Citrus sinensis leaves inoculated with the wild type X. citri subsp. citri and with a mutant strain lacking the LOV protein by a cDNA microarray and evaluated the differentially regulated genes corresponding to specific biological processes. A down-regulation of photosynthesis-related genes (together with a corresponding decrease in photosynthesis rates) was observed upon bacterial infection, this effect being more pronounced in plants infected with the lov-mutant bacterial strain. Infection with this strain was also accompanied with the up-regulation of several secondary metabolism- and defense response-related genes. Moreover, we found that relevant plant physiological alterations triggered by pathogen attack such as cell wall fortification and tissue disruption were amplified during the lov-mutant strain infection. These results suggest the participation of the LOV-domain protein from X. citri subsp. citri in the bacterial counteraction of host plant defense response, contributing in this way to disease development.

Tagetes lucida Cav. (Asteraceae) es una especie nativa de América tropical, comúnmente usada en medicina vernácula y también como medicamento fitoterápico. La infusión se emplea como tónico para combatir la tos, dolores de cabeza, fiebre, cólicos, dolores abdominales, enfermedades gastrointestinales, dolor corporal y como emenagoga. Los extractos etanólicos de hojas de T. lucida presentan actividad bactericida. El objetivo de este trabajo fue realizar la micrográfica analítica de las partes usadas de esta especie a los fines de la estandarización de la droga cruda. Para ello, se estudió la morfología foliar, la epidermis de la hoja, los estomas, la arquitectura foliar, la estructura interna de hojas, tallos, inflorescencias y flores. En los tallos se han determinado dos tipos de estructuras secretoras coexistentes, conductos y cavidades secretoras de origen esquizógeno; mientras que en las hojas y brácteas involucrales solo encontramos cavidades. Los conductos secretores se caracterizan por presentar escaso diámetro, epitelio secretor uniestratificado y vaina parenquimática. En tanto, las cavidades secretoras son de diámetro conspicuo y epitelio secretor pluriestratificado sin la vaina parenquimática. Esta información es requerida no solo para los procedimientos de identificación que garanticen la utilización de la droga vegetal, sino para el control de calidad exigido en la producción de medicamentos fitoterápicos.

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Tagetes lucida Cav. (Asteraceae) es una especie nativa de América tropical, comúnmente usada en medicina vernácula y también como medicamento fitoterápico. La infusión se emplea como tónico para combatir la tos, dolores de cabeza, fiebre, cólicos, dolores abdominales, enfermedades gastrointestinales, dolor corporal y como emenagoga. Los extractos etanólicos de hojas de T. lucida presentan actividad bactericida. El objetivo de este trabajo fue realizar la micrográfica analítica de las partes usadas de esta especie a los fines de la estandarización de la droga cruda. Para ello, se estudió la morfología foliar, la epidermis de la hoja, los estomas, la arquitectura foliar, la estructura interna de hojas, tallos, inflorescencias y flores. En los tallos se han determinado dos tipos de estructuras secretoras coexistentes, conductos y cavidades secretoras de origen esquizógeno; mientras que en las hojas y brácteas involucrales solo encontramos cavidades. Los conductos secretores se caracterizan por presentar escaso diámetro, epitelio secretor uniestratificado y vaina parenquimática. En tanto, las cavidades secretoras son de diámetro conspicuo y epitelio secretor pluriestratificado sin la vaina parenquimática. Esta información es requerida no solo para los procedimientos de identificación que garanticen la utilización de la droga vegetal, sino para el control de calidad exigido en la producción de medicamentos fitoterápicos.