Proyectos

Climate projections anticipate an increase in frequent droughts, episodes of extreme fire behavior, in addition to heat waves and unstable atmospheric conditions, all phenomena related to climate change. Drought intensification has been projected to increase in frequency in several regions across the globe, including the southwestern part of South America, the European Mediterranean Basin, Northern Africa, the Middle East, Central Asia, Australia, and the USA. Particularly, the former three areas have been recognized as locations highly likely to face unprecedented droughts during the 21st century, and within Southwestern South America, Chile has been alarmingly pointed out as the country earlier in this era experiencing this phenomenon, regardless of the greenhouse gas emissions scenario. Catastrophic effects such as extreme droughts and changes in fire behavior are important drivers of ecosystem degradation in arid, semiarid, dry temperate and Mediterranean ecosystems. Mediterranean ecosystems of central Chile have been indicated as the earliest in its type experiencing effects of climate change; where an accelerated aridification is already registered; therefore, representing a scenario to anticipate the effects of climate anomalies at other ecosystems of its type. Persistent droughts and land burning can compromise belowground conditions that are essential to support aboveground life in terrestrial ecosystems. Nevertheless, despite their importance for ecosystem functioning and recovery after environmental disturbances, there still a considerable lack of comprehension on how belowground attributes respond to combined stressors such as droughts and fires. This is of particular concern in conditions where post-fire plant and soil recovery have been shown to be inhibited or retarded due to severe droughts. Therefore, this project aims to evaluate individual and combined effects of drought and fires over time in soil microbial communities and carbon and nitrogen functional dynamics along with the relationship of these attributes and the state of sclerophyll vegetation in Mediterranean forests of central Chile. To accomplish this goal a multiscale approach will be applied in this research by integrating scientific disciplines from landcape ecology to molecular biology. By using remote sensing study site will be selected within an area known to be affected by an extended drought period (since 2010), in addition to hyper-dry years (2019 and 2021), which in addition has experienced the occurrence of historical wildfires as the case of 2017. From this initial screening 18 study conditions resulting from three climate anomaly categories identified (high, medium, low) according to differences in precipitation with respect to historical average, three categories for forest response to drought (recovered, unaffected and unrecovered) based on analysis of Normalized Burn Index (NBR = [NIR - SWIR] / [NIR + SWIR]) and two burned conditions (with and without) will be obtained for soil and vegetation assessments. Classical soil physicochemical analyses and NG-sequencing techniques including high-throughput amplicon sequencing (metabarcoding), whole genome sequencing (metagenomics), and gene expression (metatransciptomics), in addition to soil physiological analyses will be performed. Moreover, vegetation recovery following drought and fire will be evaluated. Results from this study will allow to better understand the individual versus the combined effects of drought and fires in soil microbial community structure and carbon and nitrogen functionality, which are expected to be exacerbated with the combined occurrence of these phenomena, giving insights on the resilience capacity of soil microbiomes and carbon and nitrogen biogeochemical cycles. From this work, results will also allow to gain a more comprehensive understanding of the linkages between soil functionality and vegetation responses to drought and fires over time, which will allow to identify ecological drivers related to ecosystem stability.

Síntesis de espinela MFe2O4 (M = Mg, Mn, Cu) mediante dos métodos de preparación. Posteriormente estos materiales serán unidos a biocarbones obtenidos desde cáscaras de avena, y se evaluarán en la degradación de contaminantes emergentes seleccionados.

Climate projections anticipate an increase in frequent droughts, episodes of extreme fire behavior, in addition to heat waves and unstable atmospheric conditions, all phenomena related to climate change. Drought intensification has been projected to increase in frequency in several regions across the globe, including the southwestern part of South America, the European Mediterranean Basin, Northern Africa, the Middle East, Central Asia, Australia, and the USA. Particularly, the former three areas have been recognized as locations highly likely to face unprecedented droughts during the 21st century, and within Southwestern South America, Chile has been alarmingly pointed out as the country earlier in this era experiencing this phenomenon, regardless of the greenhouse gas emissions scenario. Catastrophic effects such as extreme droughts and changes in fire behavior are important drivers of ecosystem degradation in arid, semiarid, dry temperate and Mediterranean ecosystems. Mediterranean ecosystems of central Chile have been indicated as the earliest in its type experiencing effects of climate change; where an accelerated aridification is already registered; therefore, representing a scenario to anticipate the effects of climate anomalies at other ecosystems of its type. Persistent droughts and land burning can compromise belowground conditions that are essential to support aboveground life in terrestrial ecosystems. Nevertheless, despite their importance for ecosystem functioning and recovery after environmental disturbances, there still a considerable lack of comprehension on how belowground attributes respond to combined stressors such as droughts and fires. This is of particular concern in conditions where post-fire plant and soil recovery have been shown to be inhibited or retarded due to severe droughts. Therefore, this project aims to evaluate individual and combined effects of drought and fires over time in soil microbial communities and carbon and nitrogen functional dynamics along with the relationship of these attributes and the state of sclerophyll vegetation in Mediterranean forests of central Chile. To accomplish this goal a multiscale approach will be applied in this research by integrating scientific disciplines from landcape ecology to molecular biology. By using remote sensing study site will be selected within an area known to be affected by an extended drought period (since 2010), in addition to hyper-dry years (2019 and 2021), which in addition has experienced the occurrence of historical wildfires as the case of 2017. From this initial screening 18 study conditions resulting from three climate anomaly categories identified (high, medium, low) according to differences in precipitation with respect to historical average, three categories for forest response to drought (recovered, unaffected and unrecovered) based on analysis of Normalized Burn Index (NBR = [NIR - SWIR] / [NIR + SWIR]) and two burned conditions (with and without) will be obtained for soil and vegetation assessments. Classical soil physicochemical analyses and NG-sequencing techniques including high-throughput amplicon sequencing (metabarcoding), whole genome sequencing (metagenomics), and gene expression (metatransciptomics), in addition to soil physiological analyses will be performed. Moreover, vegetation recovery following drought and fire will be evaluated. Results from this study will allow to better understand the individual versus the combined effects of drought and fires in soil microbial community structure and carbon and nitrogen functionality, which are expected to be exacerbated with the combined occurrence of these phenomena, giving insights on the resilience capacity of soil microbiomes and carbon and nitrogen biogeochemical cycles. From this work, results will also allow to gain a more comprehensive understanding of the linkages between soil functionality and vegetation responses to drought and fires over time, which will allow to identify ecological drivers related to ecosystem stability.

Este proyecto investiga el impacto de la co-contaminación por antibióticos veterinarios y metales/iones inorgánicos en suelos, un problema emergente asociado a prácticas agrícolas intensivas como la aplicación de estiércol, fertilización intensiva y riego con aguas residuales. La investigación se centra en comprender cómo la formación de complejos antibiótico-metal/ión influye en procesos clave como la adsorción, degradación, transporte en el suelo y absorción por plantas, así como en la actividad y estructura de las comunidades microbianas. Para ello, se evaluarán distintos tipos de suelos relevantes en sistemas agropecuarios intensivos en Chile, integrando modelación de transporte de solutos, estudios de especiación química, experimentos en columnas de suelo y análisis de absorción vegetal. Los resultados permitirán mejorar la comprensión del destino ambiental de estas mezclas complejas de contaminantes y aportar bases científicas para el desarrollo de estrategias de manejo, mitigación y remediación de suelos afectados.

Learning through auditory stimuli: effect of music previously conditioned with nutritional and non-nutritional rewards on the performance and welfare of nursery pigs.

Plants, with their two-layered immune system, are equipped to combat pathogen invasion. The first layer, Pattern Triggered Immunity (PTI), is a powerful defense mechanism. It relies on Pattern Recognition Receptors (PRRs) to detect Microbe-Associated Molecular Patterns (MAMPs) from microbes, triggering a robust defense response. This response, including signaling cascades, gene expression changes, and production of antimicrobials and defense hormones, contributes to restricting pathogen colonization. PTI activation can trigger a systemic response known as Induced Systemic Resistance (IRS), enhancing plant defenses throughout the organism and leading to Non-Host-Resistance. The potential of PTI activation to enhance a plant's overall defensive capacity is a promising strategy to improve crop health. PTI activation at infection sites triggers the production of mobile signals within the plant, which then spread IRS throughout the plant, enhancing its overall defensive capacity. Flg22 and xyn11, two well-known MAMPs, trigger PTI in tomato, activating various defense responses and, interestingly, including IRS in tomatoes and other plants. Plant roots, often overlooked in discussions of plant immune systems, possess their own immune system, though less potent than leaves. They respond to MAMPs like Flg22 and chitin, but with weaker production of defense chemicals. Despite this difference, roots activate various defenses like PR proteins and callose deposition. Uniquely, roots secrete antifungal secondary metabolites like flavonoids. These root exudates play a crucial role in shaping the surrounding microbiome, attracting beneficial microbes, and possess antimicrobial activity itself. Studies have shown that root exudate composition can be manipulated to influence the soil microbiome and potentially enhance plant growth. This underlines the importance of considering roots in our understanding of plant immune systems, particularly how defense responses are displayed in the root after immune activation in leaves in terms of a systemic immune response. This often overlooked aspect is crucial for a comprehensive understanding of plant immunity. Plants and microbes communicate two-way, establishing an interaction, by instance, plant root exudates influence the composition of the rhizosphere microbiome, which in turn regulates plant growth and immunity. Research suggests that specific bacteria within the rhizosphere microbiome can enhance plant immunity. In fact, transplanting the microbiome from a resistant tomato variety to a susceptible one improved disease resistance. Understanding this plant-microbiome-soil interaction is crucial for developing sustainable agriculture. Our ongoing research investigates how soil type influences tomato immunity and its connection to the soil microbiome. Preliminary results show that different soil types affect the strength of plant immunity responses, even though the overall bacterial types (phyla) are similar. Interestingly, specific bacterial isolates from a soil type with higher immunity were able to directly trigger plant defense mechanisms. Unraveling the intricate interplay between soil type, the rhizosphere microbiome, and tomato immunity holds the key to unlocking sustainable and resilient agricultural practices. This proposal aims to investigate the potential of targeted Pattern-Triggered Immunity (PTI) activation in tomato leaves to enhance plant defense against diverse pathogens. We hypothesize that leaf application of microbial elicitors (flg22 and Xyn11) will trigger PTI, leading to changes in root gene expression and root exudate composition. These alterations are expected to enrich beneficial bacteria in the rhizosphere microbiome, ultimately enhancing resistance against both the foliar pathogen Pseudomonas syringae pv. tomato and the soil-borne pathogen Fusarium oxysporum f.sp. lycopersici. To achieve this, we have defined three specific objectives: 1) Evaluate the impact of leaf-applied elicitors on pathogen susceptibility, root gene expression, root exudate composition, and soil microbiome composition. 2) Develop synthetic exudates mimicking PTI-activated plants and construct synthetic microbial communities potentially containing beneficial bacteria. 3) Assess the effectiveness of leaf-applied elicitors and synthetic microbial communities on the root microbiome and plant health under field conditions. With this, we aim to elucidate the mechanisms by which leaf-based PTI activation influences root-level processes and shapes the rhizosphere microbiome to enhance tomato plant defense against various pathogens. The findings hold promise for developing novel and sustainable strategies for disease management in tomato production.

We propose a three-stage study to explore the roles of BCRNF on NUE, wheat productivity, and nutritional grain quality. In Stage 1, we will assay the effect of BCRNFs on N-dynamics and chemical soil properties through soil incubations performed under controlled conditions for 90 days. We will measure N-losses periodically through volatilization of NH3 and NO2. Additionally, we will quantify potentially mineralizable nitrogen (PMN), changes in the C:N ratio, and changes in pH and soil nutrient content during nine sampling dates. In Stage 2, two independent experiments will be conducted to evaluate the interaction among BCRNFs with soil and its effect on the morphological, physiological, and biochemical plant adaptive strategies related to NUE. In Experiment 1, wheat will be harvested at the pre-anthesis growth stage, and plant growth parameters and N concentration in tissues will be used to determine N uptake efficiency (NUPE). Additionally, it will measure plant adaptative strategies related to N-uptake, such as root architecture, exudation of organic acids by roots, and changes in enzymatic and microbial activities in the soil. In Experiment 2, wheat plants will be harvested at the maturity stage to evaluate the relationship between grain yield and N concentration to determine N utilization efficiency (NUTE). Plant adaptive strategies related to NUTE will also be assessed, including N-translocation and remobilization, CO2 assimilation rate (A), stomal conductance (gs), photosynthesis per unit of N, PNUE. In addition, the leaf response to the fluorescence and stay green trait will also be performed. The amount of nitrogen in grain derived from the fertilizer (Ndff) will be calculated using the δ15N values obtained from grains. In Stage 3, the effect of BCRNFs on wheat productivity and nutritional quality will be evaluated in field conditions. The trials will be conducted over two agricultural seasons, and the impact of BCRNFs on soil and plant samples will be assessed at three different stages: anthesis, soft dough grain, and hard dough grain. During these stages, the chemical properties of the soil, as well as microbial and enzymatic activities, will be evaluated. Photosynthetic parameters such as A, gs, Ci, E, Fo, Fm, and QY will be quantified. The plant height, harvest index, and yield components will be assessed at the end of each growing season. Grain quality indicators like protein content, gluten levels, and sedimentation rate will also be measured. Finally, the amount of nitrogen in grain derived from the fertilizer (Ndff) will be calculated using the δ15N values obtained from grains. This proposal focused on understanding the interconnections among soil, N-fertilizer, and plant physiology, using wheat as a model crop. The primary aim is to boost N management strategies in agriculture, ensuring a balance between productivity and sustainability. The initiative seeks to create a technological solution to enhance NUE, reduce environmental impact, and ensure global food security.

Evaluación del Subsidio Ecológico de Cóndores y Águilas Chilenas en el Relleno Sanitario La Yesca, Región de O'Higgins" Objetivo General Evaluar el uso del relleno sanitario La Yesca por cóndores y águilas chilenas como un subsidio ecológico y caracterizar los patrones de actividad de estas especies en relación con los residuos disponibles (aún la chica no sabe con cual especie trabajará porque no hemos visitado el lugar, pero algo asi estamos diseñando). Objetivos Específicos Determinar la frecuencia y duración de las visitas de cóndores y águilas chilenas al relleno sanitario La Yesca mediante el uso de cámaras trampa. Identificar los patrones estacionales de actividad de cóndores y águilas chilenas en el relleno sanitario a lo largo del año. Comparar el uso del relleno sanitario por ambas especies y analizar si existen diferencias en el comportamiento de aprovechamiento de recursos antropogénicos.

Fluctuaciones glaciares del Cuaternario tardío en Chile central: bases para comprender el pasado, presente y futuro del clima”.

Fluctuaciones glaciares del Cuaternario tardío en Chile central: bases para comprender el pasado, presente y futuro del clima”.