Ciencia y Tecnología

“El espíritu de Marburgo” recorre la Estética operatoria: Luis Juan Guerrero, lector “evolutivo” de Heidegger

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“El espíritu de Marburgo” recorre la Estética operatoria: Luis Juan Guerrero, lector “evolutivo” de Heidegger; “‘The Spectre of Marburg’ wanders around the Operative Aesthetics: Luis Juan Guerrero, ‘Evolutive’ Reader of Heidegger” Belgrano, Mateo En el presente trabajo nos proponemos analizar la lectura de Martin Heidegger en la Estética operatoria por parte de Luis Juan Guerrero. La tesis a defender consiste en que “El origen de la obra de arte” tiene un rol central en la obra del filósofo argentino. Pero esto no quiere decir que Guerrero no sea un autor original o que sea un mero comentador del filósofo alemán, sino todo lo contrario: el filósofo argentino hace una lectura productiva de Heidegger a partir de la cual elabora una filosofía propia y auténtica. Centrándonos en el ensayo sobre el arte de Heidegger y el primer tomo de la Estética operatoria, analizaremos tres puntos neurálgicos: el concepto de útil, la relación mundo y tierra y el vínculo entre historia y verdad.; This paper aims to analyse the reading of Martin Heidegger’s thought offered by Luis Juan Guerrero in his Operative Aesthetics. I claim that “The Origin of the Work of Art” plays a central role in the work of the Argentinian philosopher. However, this does not mean that Guerrero is not an original author or that he is a mere commentator of the German philosopher. On the contrary: the Argentinian philosopher offers a productive reading of Heidegger which allows him to build his own and authentic philosophy. By focusing on Heidegger’s essay on art and on the first volume of the Operative Aesthetics, this paper analyses three essential issues: the concept of tool, the world-earth relationship, and the bond between history and truth.

Effects of elevated CO2 on feeding responses of biological control agents of Pontederia crassipes

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Effects of elevated CO2 on feeding responses of biological control agents of Pontederia crassipes Paper, M.K.; Righetti, Tomás; Raubenheimer, S.L.; Coetzee, J.A.; Sosa, Alejandro Joaquín; Hill, M.P. Elevated carbon dioxide (eCO2) and rising temperatures will have far-reaching effects on global plant-insect interactions, yet their implications for future biological control programs are not fully understood. Studies have shown that elevated CO2 will affect insect feeding guilds differently and these responses can be predicted with some confidence. Water hyacinth, Pontederia crassipes Mart. (Pontederiaceae), is a native and representative species of the Del Plata wetlands (Argentina) that invades outside of its native environment. It is considered one of the world's worst aquatic weeds and a target for biological control. In this study, water hyacinth plants were grown under two CO2 concentrations – current (400 p.p.m.) or elevated (800 p.p.m.) –, with and without two biocontrol agents representing different feeding guilds, the leaf-chewing Cornops aquaticum Brüner (Orthoptera: Acrididae) and the phloem-feeding Megamelus scutellaris Berg (Hemiptera: Delphacidae). Under eCO2 concentration, photosynthetic rate, total dry weight, and relative growth rate of P. crassipes acclimated to eCO2 conditions and plants showed very little CO2 fertilization response in eutrophic water. Insect herbivory varied depending on feeding guilds at eCO2; however, P. crassipes growth responses increased when exposed to insect herbivory. Chewing herbivory by C. aquaticum was consistent across CO2 conditions, whereas the feeding by M. scutellaris increased substantially at eCO2. These results indicate that successful biological control of P. crassipes under conditions of elevated CO2 might rely on phloem-feeding insects, with chewers playing a lesser role.

A new elasmosaurid (Sauropterygia, Plesiosauria) from the upper levels of the La Colonia Formation (upper Maastrichtian), Chubut Province, Argentina

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A new elasmosaurid (Sauropterygia, Plesiosauria) from the upper levels of the La Colonia Formation (upper Maastrichtian), Chubut Province, Argentina O'gorman, Jose Patricio; Carignano, Ana Paula; Calvo Marcilese, María Lydia Valentina; Perez Panera, Juan Pablo A new elasmosaurid, Chubutinectes carmeloi gen. et sp. nov., from the Chubut Province, Argentina, is described. The holotype and only specimen of this species (MPEF-PV 5232) was collected from the La Colonia Formation. Chubutinectes carmeloi gen. et sp. nov. is among the few upper Maastrichtian elasmosaurids from the Southern Hemisphere whose postcranial anatomy is well known. It can be distinguished from other elasmosaurids by the following combination of characters: middle cervical centra longer than high with lateral keel and bilobate articular faces; pectoral and anterior dorsal centra with bilobate articular faces; coracoids with closed cordiform fenestra and long anterior coracoids process; high ratio coracoids/scapular length; ilium with angled shaft; pubis with small lateral cornua; humerus with posterior expansion ending in accessory facet and epipodial facets of humerus almost aligned; accessory ossification between tibia and tibial, and radius and radial. Preliminary phylogenetic analysis recovered Chubutinectes carmeloi gen. et sp. nov. within the Weddellonectia clade, including the Late Cretaceous Wedellian aristonectine elasmosaurids. The study of the associated microfossiliferous assemblages (micro- and nanofossils) suggests a marine inner neritic paleoenvironment, with restricted circulation and warm waters. The presence of Micula prinsii and Micula murus at this latitude indicates a latest Maastrichtian age, upper part of the UC20d sub-biozone and younger than ∼67,3 Ma.

Microplastic pollution in marine environments: Exploring sources, sinks, and consequences with a focus on algal interactions

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Microplastic pollution in marine environments: Exploring sources, sinks, and consequences with a focus on algal interactions Salomone, Vanesa Natalia; Passucci, Victoria; Areco, María del Mar The widespread use of plastics and their low recycling rate has led to a very serious environmental problem, as plastics accumulate at an alarming rate, with effects that have not yet been thoroughly studied. Due to their small size, microplastics have become ubiquitous in various ecosystems. Furthermore, they enter organisms through multiple pathways, posing a threat to different species. The interaction between microplastics and algae, fundamental elements of aquatic food chains, has significant implications for the overall health of ecosystems. This review analyses the information published in scientific articles and official reports on the occurrence and effects of microplastics in the marine environment, particularly on algae, and their potential use for microplastic remediation. Results published demonstrate that despite the locations, it may seem that microplastics are present in all types of environments around the world. They are accumulated in sediments, seagrass, and throughout the food web. In marine environments, polyethylene is the most common polymer found, followed by polypropylene, with fibres and fragments being the most common forms. Several papers report different alga-microplastic interactions. These interactions offer opportunities for potential solutions to marine plastic pollution, as they could be used in the remediation of microplastics, due to their high adsorption capacity. However, extensive research is needed to determine the most suitable algal species, optimal conditions, practical challenges, and potential risks associated with this phycoremediation approach. The main gap in the literature is that current research often lacks precision in quantifying microplastic concentrations, which hinders the ability to accurately assess the associated risks, particularly to edible species. To address these challenges, the development of standardized protocols and reliable analytical techniques is essential. Urgent and systematic research on microplastics is needed to understand their sources, distribution, impacts and risks, to inform environmental and human health policies, and promote sustainable alternatives to plastics.

On characteristic invariants of matrix pencils and linear relations

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On characteristic invariants of matrix pencils and linear relations Gernandt, Hannes; Martinez Peria, Francisco Dardo; Philipp, Friedrich; Trunk, Carsten Joachim The relationship between linear relations and matrix pencils is investigated. Given a linear relation, we introduce its Weyr characteristic. If the linear relation is the range (or the kernel) representation of a given matrix pencil, we show that there is a correspondence between this characteristic and the Kronecker canonical form of the pencil. This relationship is exploited to obtain estimations on the invariant characteristics of matrix pencils under rank-one perturbations.

Unraveling swine hepatitis E in the central region of Argentina through ELISA development and epidemiological insights

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Unraveling swine hepatitis E in the central region of Argentina through ELISA development and epidemiological insights Gutiérrez, Silvina Elena; Arce, Lorena Paola; Bence, Angel Ricardo; Matias Brancher, Julia Rafaela; Rivero, Mariana Alejandra; Moran, María Celeste; Vizoso Pinto, María Guadalupe; Estein, Silvia Marcela Hepatitis E virus (HEV) is a public health concern globally, causing acute viral hepatitis in humans. Genotype-3 HEV (HEV-3), the most frequently genotype detected in South America, is zoonotic and the main reservoirs are the domestic pig and wild boar. Circulation of HEV-3 in Argentina has been confirmed in humans as well as in pig herds, wild boar and environmental waters. However, data are scarce mainly due to the inaccessibility of serological assays in this country. In order to provide insights in the epidemiology of HEV in swine in Argentina, we developed an indirect ELISA based on the native recombinant protein ORF2 and conducted a serological survey to determine the prevalence of seropositive swine in small-scale pig farms in the central region of Argentina. The method was evaluated in a panel of 157 serum samples, resulting in relative sensitivity of 98.6 % (95 % CI 95 %−100 %) and relative specificity of 97.7 % (95 % CI 94 %−100 %) compared to a commercial test. An almost perfect agreement was obtained between the two tests (Kappa index of 0.961). A survey on 294 samples from 49 small-scale farms resulted in a seropositivity rate of 54 %. Seropositive animals were found in 34 out of 49 (69.4 %) farms. Most of the farms (70.6 %) had over 50 % of seropositive animals. The wide spreading of HEV in the swine population of Tandil, Argentina, underscore the need to better understand the epidemiology of HEV in the region, enabling the implementation of targeted interventions to mitigate the impact of this virus on public health.

Computational approaches to explainable artificial intelligence: advances in theory, applications and trends

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Computational approaches to explainable artificial intelligence: advances in theory, applications and trends Górriz, J. M.; Álvarez Illán, I.; Álvarez Marquina, A.; Arco, J. E.; Atzmueller, M.; Ballarini, Fabricio Matias; Barakova, E.; Bologna, G.; Bonomini, Maria Paula; Castellanos Dominguez, G.; Castillo Barnes, D.; Cho, S. B.; Contreras, R.; Cuadra, J. M.; Domínguez, E.; Domínguez Mateos, F.; Duro, R. J.; Elizondo, D.; Fernández Caballero, A.; Fernández Jover, Eduardo; Formoso, M. A.; Gallego Molina, N. J.; Gamazo, J.; García González, J.; Garcia Rodriguez, J.; Wang, W.; Zhang, Y. D.; Zhu, H.; Zhu, Z.; Ferrández Vicente, J. M. Deep Learning (DL), a groundbreaking branch of Machine Learning (ML), has emerged as a driving force in both theoretical and applied Artificial Intelligence (AI). DL algorithms, rooted in complex and non-linear artificial neural systems, excel at extracting high-level features from data. DL has demonstrated humanlevel performance in real-world tasks, including clinical diagnostics, and has unlocked solutions to previously intractable problems in virtual agent design, robotics, genomics, neuroimaging, computer vision, and industrial automation. In this paper, the most relevant advances from the last few years in Artificial Intelligence (AI) and several applications to neuroscience, neuroimaging, computer vision, and robotics are presented, reviewed and discussed. In this way, we summarize the state-of-the-art in AI methods, models and applications within a collection of works presented at the 9th International Conference on the Interplay between Natural and Artificial Computation (IWINAC). The works presented in this paper are excellent examples of new scientific discoveries made in laboratories that have successfully transitioned to real-life applications.

Ethanolic extract of Aloe arborescens stimulates neonatal rat calvarial cells proliferation, migration and osteogenic differentiation

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Ethanolic extract of Aloe arborescens stimulates neonatal rat calvarial cells proliferation, migration and osteogenic differentiation Blanco, Nicolás Olegario; Gili, Valeria; Laiuppa, Juan Andrés; Santillán, Graciela Edith The medicinal plant Aloe arborescens Miller has chemical compounds that could stimulate the activity of bone-forming cells, but no studies have been found in this regard. We evaluated the effects of different dilutions of aqueous (1/10; 1/100; 1/1000) or ethanolic (1/1000; 1/2000; 1/5000) extracts of parenchyma from A. arborescens on the viability, proliferation, migration and osteogenic differentiation of primary cell cultures from neonatal rat calvaria. In none of the conditions studied did cell viability decrease (p ≤ 0.01). Furthermore, the 1/5000 ethanolic extract dilution showed a positive effect on cell viability at 48 h and 72 h and the latter was correlated with a 27 % (p ≤ 0.01) increase in cell proliferation. Ethanolic extract significantly stimulated cell migration and cultured mineralization with respect to control, showing the maximal effect at a dilution 1/5000. Together, the results show that the A. arborescens extracts do not have toxic effects. In addition, ethanolic extract stimulates proliferation, migration and osteogenic differentiation of rat calvarial cells, suggesting a potential bone anabolic action.

Practical diagnostic algorithms for Chagas disease: a focus on low resource settings

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Practical diagnostic algorithms for Chagas disease: a focus on low resource settings Gabaldón Figueira, Juan Carlos; Skjefte, Malia; Longhi, Silvia Andrea; Escabia, Elisa; García Casares, Lady Juliette; Ros Lucas, Albert; Martínez Peinado, Nieves; Muñoz Calderon, Arturo Alejandro; Gascón, Joaquim; Schijman, Alejandro Gabriel; Alonso Padilla, Julio Introduction: Chagas disease, caused by parasite Trypanosoma cruzi, is the most important neglected tropical disease in the Americas. Two drugs are available for treatment, but access to them is challenging, in part due to complex diagnostic algorithms. These are stage-dependent, involve multiple tests, and are ill-adapted to the reality of vast areas where the disease is endemic. Molecular and serologic tools are used to detect acute and chronic infections, with the performance of the latter showing geographic differences. Breakthroughs in the development of new diagnostic tools include the validation of a loop-mediated isothermal amplification assay for acute infections (T. cruzi-LAMP), and the regional validation of several rapid diagnostic tests (RDTs) for chronic infection, which simplify testing in resource-limited settings. The literature search was carried out in the MEDLINE database until 1 August 2023.Areas covered: This review outlines existing algorithms, and proposes new ones focused on point-of-care testing.Expert opinion: Integrating point-of-care testing into existing diagnostic algorithms in certain endemic areas will increase access to timely diagnosis and treatment. However, additional research is needed to validate the use of these techniques across a wider geography, and to better understand the cost-effectiveness of their large-scale implementation.

Two-weight boundedness for local fractional maximal and applications

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Two-weight boundedness for local fractional maximal and applications Ramseyer, Mauricio Javier; Salinas, Oscar Mario; Toschi, Marisa Given Ω a proper open subset of a metric space with the weak homogeneity property and a measure μ doubling on certain local balls, we give sufficient conditions about local weights for the two-weight boundedness of the local fractional maximal operator acting on weighted Lebesgue spaces. As applications we obtain analogous results for singular and fractional type operators and their commutators. As a further application we present an a priori estimate for solutions of Δ mu= f in Ω , acting in weighted Sobolev spaces involving the distance to the boundary and different local weights.

Editorial: Fusarium species as plant and human pathogens, mycotoxin producers, and biotechnological importance

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Editorial: Fusarium species as plant and human pathogens, mycotoxin producers, and biotechnological importance Chulze, Sofia Noemi; Tittlemier, Sheryl; Torres, Adriana Mabel The fungal genus Fusarium Link includes many plant pathogens of agricultural crops, human pathogens, and species with biotechnological applications (Leslie and Summerell, 2006; Aoki et al., 2014; Meyer et al., 2020; Geiser et al., 2021). The main concern in the last decades has been devoted to those species that infect staple crops and produce secondary metabolites known as mycotoxins. Mycotoxins produced by Fusarium species have been shown to occur worldwide. Among these, fumonisins and trichothecenes are of great concern for their impact on human and animal health (Munkvold et al., 2021). Under a scenario of climate change, the situation can worsen due to changes in fungal biodiversity, in the resistance/resilience of crops, and in the strong impact of the environmental factors affecting both global food security and safety (Singh et al., 2023).

Datos de campo eléctrico atmosférico, viento, temperatura, humedad relativa y presión desde el 2017 al 2021 cada 5 segundos (Vicente López, Buenos Aires, Argentina)

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Datos de campo eléctrico atmosférico, viento, temperatura, humedad relativa y presión desde el 2017 al 2021 cada 5 segundos (Vicente López, Buenos Aires, Argentina) El campo eléctrico atmosférico (E) o gradiente de potencial(E= -PG) es una variable muy útil para el monitoreo atmosférico desde un punto de vista eléctrico. Puede ser utilizado para estudiar tanto los días de buen tiempo como aquellos con tormentas, vientos fuertes, mucha nubosidad, etc. El estudio de días de buen tiempo puede incluir el análisis del efecto global que tienen las tormentas sobre el PG en el sitio de medición como el efecto local de los aerosoles sobre PG. Existen estudios que indican un efecto de mayor escala temporal sobre este dato como El Niño. En cuanto a los días que no son de buen tiempo se encuentra en la literatura que PG puede ser utilizado en sistemas de alerta ante descargas eléctricas. El estudio del desarrollo de las tormentas también puede ser implementado con esta variable. En cuanto al uso que se les da a las variables convencionales como la temperatura, viento, presión y humedad relativa puede ir desde estudios asociados a meteorología como a la salud en el caso de propagación de enfermedades.

El rostro del otro y la otreidad del testimonio: Gaspar Risco Fernández y Luis “Tito” Mangini

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El rostro del otro y la otreidad del testimonio: Gaspar Risco Fernández y Luis “Tito” Mangini Herrero Jaime, Susana Inés El cierre de 11 de los 27 ingenios en funcionamiento en Tucumán durante la dictadura de Juan Carlos Onganía, sumió a la provincia en una profunda crisis. Trabajadores, organizaciones, estudiantes y religiosos se plegaron a las manifestaciones suscitadas por las medidas del azúcar, y su radicalización creciente condujo a los dos “tucumanazos”ocurridos entre 1969 y 1972. En el campo de la cultura, una serie de obras artísticas, políticas e intelectuales, acompañaron esta reacción, buscando “amparar ,aunque fuera simbólicamente” a los trabajadores expulsados fuera del sistema (Orquera, 2010,268). Dentro de ese grupo se ubican “El hombre en la zafra” (1968) muestra fotográfica de Luis “Tito” Mangini y el proyecto de “Promoción Cultural” (1968-1971) desarrollado por el filósofo Gaspar Risco Fernández. Sin embargo, la sensibilidad ante el cierre de los ingenios no fue lo único que relacionó a Risco y a Mangini. Por el contrario, existió entre ellos una amistad que se tradujo en trabajos y colaboraciones. Mangini es el autor del retrato que ilustra El campesino tucumano, educación y cultura (1969)3 libro que recoge la experiencia de “Promoción Cultural” desarrollada por Risco. Por su parte, el filósofo escribió algunos de los catálogos de las muestras del fotógrafo y los publicó en Tucumán: mito, aventura y misterio. Los Otros testigos (1994). En este marco nos preguntamos cuál fue la lectura que el filósofo realizó de la obra de Mangini, y por qué consideró que sus fotos expresaban ese Tucumán “otro”, que emerge entre cañaverales, ingenios y conflictos.

A Critical Analysis of Target Ionization and Projectile Electron Loss in Neutral– and Ion–Atom Collisions

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A Critical Analysis of Target Ionization and Projectile Electron Loss in Neutral– and Ion–Atom Collisions Quinto, Michele Arcangelo; Esponda, Nicolás Julián; Rojas Barillas, María Fernanda; Rivarola, Roberto Daniel; Monti, Juan Manuel Electron removal (target ionization and/or projectile electron loss) in neutral–atom collisions is theoretically studied for the impact of H0 , He0 and He+ beams on noble gases (He, Ne and Ar). These reactions are investigated theoretically within the Continuum Distorted Wave-Eikonal Initial State model. New features have been included in the theoretical model: (i) a scaled projectile charge depending on its velocity and charge, (ii) a dynamic projectile-effective-charge depending on the momentum transfer, and (iii) a dynamic target-effective-charge depending on the kinematics of the emitted electron. The energy and angular spectra of emitted electrons from the target and from the projectile are calculated and compared with the available experimental data. Also, the influence of each one of the corrections on the resulting spectra will be studied.

Comparación y evolución de la evaporación de tanque y evapotranspiración de referencia (ETo) estimada con fórmulas en la región semiárida pampeana central

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Comparación y evolución de la evaporación de tanque y evapotranspiración de referencia (ETo) estimada con fórmulas en la región semiárida pampeana central Bazan Azargado, Ramiro Nicolas; Vergara, G.; Casagrande, G.; Mendez, Mariano Javier En las regiones semiáridas del mundo el agua es el principal factor que limita la producción agropecuaria. Conocer la demanda de agua de la atmósfera permite planificar las actividades agropecuarias para el mejor aprovechamiento de este recurso limitante. La demanda de agua de la atmósfera se expresa través de la evaporación (E)y de la evapotranspiración del cultivo de referencia (ETo) donde los parámetros de suelo y de cultivo se encuentra estandarizados. La ETo es la evapotranspiración que ocurre cuando el suelo se encuentra a capacidad de campo y con cobertura vegetal completa de un reygrass perenne de 10 a 15 cm de altura en activo crecimiento, donde las características del cultivo y la humedad en el suelo son parámetros que se mantienen estandarizados (Allen et al., 2006a). la ETo permite calcular el balance hídrico de agua en el suelo para conocer las deficiencias de agua, los excesos, la evapotranspiración real (ETR) y el agua almacenada en el suelo (Murphy y Hurtado, 2011). Además, la ETo permite conocer la evapotranspiración de cultivo (ETc) que es la necesidad de agua de un cultivo y se utiliza para calcular la necesidad de riego...

Avaliação docente na Argentina (2015-2019): O programa "Enseñar" e a hierarquização da cultura do desempenho

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Avaliação docente na Argentina (2015-2019): O programa "Enseñar" e a hierarquização da cultura do desempenho; Teacher evaluation in Argentina (2015-2019): The "Enseñar" programme and the hierarchisation of the culture of performance; La evaluación docente en Argentina (2015-2019): El programa "Enseñar" y la jerarquización de la cultura del rendimiento Rodrigo, Lucrecia; Rodriguez Moyano, Ines Este artigo tem como objetivo analisar as orientações das políticas de formação de professores, voltadas para a avaliação, que ganharam impulso na Argentina e que estão enquadradas nos recentes processos de restauração conservadora (2015-2019). Começamos por reconhecer a influência da tendência internacional e regional que situa essas experiências como instâncias de regulação do trabalho pedagógico. Em particular, investigamos o programa "Enseñar", uma iniciativa destinada a avaliar o desempenho de estudantes argentinos que estavam na fase final de sua formação de professores. O artigo enfoca os fundamentos e os propósitos do programa, bem como o histórico e as condições legais que possibilitaram a implementação da avaliação de professores com base no modelo de responsabilidade na Argentina. Conclui com alguns dos aspectos legais e políticos que definiram a viabilidade e o escopo desse programa na Argentina.; This article aims to analyse the orientations of teacher training policies, aimed at evaluation, which have gained momentum in Argentina and which are framed within the recent processes of conservative restoration (2015- 2019). We start by recognising the influence of the international and regional trend that situates these experiences as instances of regulation of pedagogical work. In particular, we investigate the "Enseñar" programme, an initiative aimed at evaluating the performance of Argentinean students who were in the final stage of their teacher training. The article focuses on the foundations and purposes of the programme, as well as the background and legal conditions that made possible the implementation of teacher evaluation based on the accountability model in Argentina. It concludes with some of the legal and political aspects that defined the viability and scope of this programme in Argentina.; El artículo se propone analizar las orientaciones de las políticas de formación docente, destinadas a la evaluación, que tomaron impulso en la Argentina y que se enmarcan dentro de los recientes procesos de restauración conservadora (2015-2019). Se parte de reconocer la injerencia de la tendencia internacional y regional que sitúa a estas experiencias como instancias de regulación del trabajo pedagógico. En particular, se indaga sobre el programa “Enseñar”, iniciativa orientada a evaluar el desempeño de los estudiantes argentinos que se encontraban en el tramo final de su formación como docentes. A partir de un estudio de tipo documental, basado en el análisis de la normativa y documentos oficiales, el artículo se focaliza en los fundamentos y propósitos, así como en los antecedentes y condiciones legales que posibilitaron en el país la implementación de la evaluación docente basada en el modelo de rendición de cuentas. Se finaliza planteando algunos aspectos legales y políticos que definieron la viabilidad y el alcance de este programa en Argentina.

Effect of stabilization time and soil chromium concentration on Sesbania virgata growth and metal tolerance

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Effect of stabilization time and soil chromium concentration on Sesbania virgata growth and metal tolerance Rodríguez, Natalia; Carusso, Sofia; Juárez, Angela Beatriz; El Kassisse, Yanina; Rodríguez Salemi, Valeria; de Cabo, Laura Isabel Sesbania virgata is a pioneer shrub from the Fabaceae family, native to riparianenvironments in northeast of Argentina, southern of Brazil and Uruguay. In peri-urbanriparian soils, metal contamination is a frequent problem, being its bioavailability partlydetermined by the stabilization time and frequency of contamination events. The effectof time elapsed between chromium (Cr) soil enrichment and plant seeding and Cr doseson S. virgata tolerance and metal absorption were evaluated. Treatments weredeveloped by adding Cr (80-400 ppm) to the soil and allowing two days or fifteenmonths to elapse before sowing, and a control treatment without Cr addition. After 150days from seeding, bioaccumulation and translocation factors, growth parameters (drybiomass and its aerial/radical allocation pattern, stem length and its elongation rate),morphological parameters (root volume and leaf area), and physiological parameters(chlorophyll content) of the specimens were determined. The emergence of S. virgatawas inhibited since 150 ppm when Cr was added to the soil two days before seeding,with Cr accumulation in roots starting at 80 ppm (17.4 ± 2.5 mg∙kg -1 ). Under 15 monthsof metal stabilization, S. virgata plants survived across the entire range of Cr dosestested, with accumulation in roots since 100 ppm (35.5 ± 0.2 mg∙kg -1 ) and metaltranslocation to aerial tissues only under 400 ppm. The results obtained showed that S.virgata did not have high BCF and TF values, suggesting that it cannot be classified asbioaccumulator of Cr under the tested conditions. However, its presence in environments contaminated with Cr can be beneficial, as it helps to stabilize the metal in the soil.

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