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.

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.

Avocado is a very nutritious and tasty fruit, characteristics that have caused a high global demand for this fruit. Increasing evidence of health benefits of the avocado is both driving increased consumption and stimulating research. The results of this study are expected not only to provide more foundation into the agronomic, biochemical and molecular aspects associated to waterlogging of ‘Hass’ avocados grafted on different rootstocks but also provide potential biomarkers and genes involved in stress tolerance and select the best suited rootstocks for the current and the upcoming extreme climate change events, which may help to implement new Hass avocado production protocols that will reduce this predicted climate change problem in practice.

Centro UOH de Biología de Sistemas para la Sanidad Vegetal (BioSaV-UOH)

Centro UOH de Biología de Sistemas para la Sanidad Vegetal (BioSaV-UOH)

We investigate how rain-mediated mechanical processes influence the spread of pathogens under field conditions. While it is well established that water is a primary vector for bacterial movement between plants, few studies have examined the detailed hydrodynamic mechanisms involved, particularly in the context of leaf morphology, surface roughness, and microbial adhesion. This gap restricts our ability to develop predictive models and preventive strategies for managing rain-borne plant diseases.
The project’s general objective is to elucidate the coupling between raindrop impact dynamics and bacterial dispersal patterns on cherry leaves under realistic rainfall conditions. Specifically, it aims to (i) characterize the mechanical interaction between raindrops and cherry leaves using high-speed imaging and physical analysis to observe the dispersal patterns of Pseudomonas syringae pv. syringae (Pss). (ii) evaluate the spatial dispersal of Pss inoculated artificially onto cherry leaves at different concentrations under controlled temperature and rainfall conditions, and (iii) develop an integrative predictive model based on physical variables of rain-leaf interaction and experimentally measured environmental conditions to estimate the dispersal and severity of Pss attack.
Methodologically, our study combines high-speed photography, controlled laboratory rain simulations, and microbiological assays. We will perform experiments in a custom-designed rainfall simulator allowing precise control of droplet size, velocity, and impact angle. Bacterial suspensions of Pseudomonas syringae—a pathogen commonly associated with cherry canker—will be applied to leaves under standardized conditions. The dynamics of droplet impact, splash formation, and secondary droplet ejection will be recorded at high temporal resolution to quantify mechanical energy transfer and spatial distribution of splashed particles. Parallel microbiological analyses will determine bacterial survival rates, concentration profiles, and the extent of leaf-to-leaf contamination. We will integrate these results into a predictive model linking rainfall characteristics to potential bacterial dispersal distances and infection probabilities.
We aim to enhance our understanding of the biophysical coupling between rainfall and pathogen mobility, establish a set of empirical relationships for disease spread modeling, and provide practical recommendations for orchard management under varying climatic scenarios. By bridging the gap between plant pathology and fluid mechanics, this project will provide a mechanistic foundation for reducing rain-mediated bacterial diseases in high-value fruit crops, contributing to the sustainability and resilience of O’Higgins agriculture.

We investigate how rain-mediated mechanical processes influence the spread of pathogens under field conditions. While it is well established that water is a primary vector for bacterial movement between plants, few studies have examined the detailed hydrodynamic mechanisms involved, particularly in the context of leaf morphology, surface roughness, and microbial adhesion. This gap restricts our ability to develop predictive models and preventive strategies for managing rain-borne plant diseases.
The project’s general objective is to elucidate the coupling between raindrop impact dynamics and bacterial dispersal patterns on cherry leaves under realistic rainfall conditions. Specifically, it aims to (i) characterize the mechanical interaction between raindrops and cherry leaves using high-speed imaging and physical analysis to observe the dispersal patterns of Pseudomonas syringae pv. syringae (Pss). (ii) evaluate the spatial dispersal of Pss inoculated artificially onto cherry leaves at different concentrations under controlled temperature and rainfall conditions, and (iii) develop an integrative predictive model based on physical variables of rain-leaf interaction and experimentally measured environmental conditions to estimate the dispersal and severity of Pss attack.
Methodologically, our study combines high-speed photography, controlled laboratory rain simulations, and microbiological assays. We will perform experiments in a custom-designed rainfall simulator allowing precise control of droplet size, velocity, and impact angle. Bacterial suspensions of Pseudomonas syringae—a pathogen commonly associated with cherry canker—will be applied to leaves under standardized conditions. The dynamics of droplet impact, splash formation, and secondary droplet ejection will be recorded at high temporal resolution to quantify mechanical energy transfer and spatial distribution of splashed particles. Parallel microbiological analyses will determine bacterial survival rates, concentration profiles, and the extent of leaf-to-leaf contamination. We will integrate these results into a predictive model linking rainfall characteristics to potential bacterial dispersal distances and infection probabilities.
We aim to enhance our understanding of the biophysical coupling between rainfall and pathogen mobility, establish a set of empirical relationships for disease spread modeling, and provide practical recommendations for orchard management under varying climatic scenarios. By bridging the gap between plant pathology and fluid mechanics, this project will provide a mechanistic foundation for reducing rain-mediated bacterial diseases in high-value fruit crops, contributing to the sustainability and resilience of O’Higgins agriculture.

Avocado is a very nutritious and tasty fruit, characteristics that have caused a high global demand for this fruit. Increasing evidence of health benefits of the avocado is both driving increased consumption and stimulating research. The results of this study are expected not only to provide more foundation into the agronomic, biochemical and molecular aspects associated to waterlogging of ‘Hass’ avocados grafted on different rootstocks but also provide potential biomarkers and genes involved in stress tolerance and select the best suited rootstocks for the current and the upcoming extreme climate change events, which may help to implement new Hass avocado production protocols that will reduce this predicted climate change problem in practice.

La Red Iberoamericana CYTED coordinada por Renato de Mello Prado (UNESP, Brasil) integra 15 grupos y 51 investigadores de Brasil, Chile, Colombia, Ecuador, México, Paraguay, Perú, Portugal y Uruguay para fomentar la colaboración en fertilidad de suelos, nutrición vegetal y manejo sustentable de cultivos, articulando universidades, institutos como Embrapa e INIA, universidades nacionales e internacionales y agencias de extensión. Dentro de este marco, el proyecto propuesto “El silicio es una estrategia para mitigar estreses para la sostenibilidad agroalimentaria de cultivos en Brasil, Perú, Paraguay, Colombia, Ecuador y Chile” (SiAgro, 2026-2029) posiciona el silicio como herramienta clave para enfrentar sequía, salinidad, enfermedades y deficiencias nutricionales en cultivos como maíz, arroz y caña, validando dosis y formas de aplicación (foliar, radicular, nano-Si), estudiando mecanismos fisiológicos, bioquímicos, moleculares (transportadores Lsi1/Lsi2, pared celular, antioxidantes) y promoviendo transferencia tecnológica para pequeños productores, con énfasis en resiliencia climática en suelos volcánicos, aluviales y tropicales.

La Red Iberoamericana CYTED coordinada por Renato de Mello Prado (UNESP, Brasil) integra 15 grupos y 51 investigadores de Brasil, Chile, Colombia, Ecuador, México, Paraguay, Perú, Portugal y Uruguay para fomentar la colaboración en fertilidad de suelos, nutrición vegetal y manejo sustentable de cultivos, articulando universidades, institutos como Embrapa e INIA, universidades nacionales e internacionales y agencias de extensión. Dentro de este marco, el proyecto propuesto “El silicio es una estrategia para mitigar estreses para la sostenibilidad agroalimentaria de cultivos en Brasil, Perú, Paraguay, Colombia, Ecuador y Chile” (SiAgro, 2026-2029) posiciona el silicio como herramienta clave para enfrentar sequía, salinidad, enfermedades y deficiencias nutricionales en cultivos como maíz, arroz y caña, validando dosis y formas de aplicación (foliar, radicular, nano-Si), estudiando mecanismos fisiológicos, bioquímicos, moleculares (transportadores Lsi1/Lsi2, pared celular, antioxidantes) y promoviendo transferencia tecnológica para pequeños productores, con énfasis en resiliencia climática en suelos volcánicos, aluviales y tropicales.