Suchergebnisse

Phyto-rhizo-remediation is a promising technology for pollutant clean-up provided by the plant holobiont, composed by the host plant and its associated microbiome. Through root exudation, the plant nurtures and shape the structure and functionality of the microbial communities inhabiting the root system. The complex interactions between the plant host and the microbiome are poorly understood, in particular in contaminated environments where the pollution stress induces specific root exudation profiles that could have a role in the activation of the microbial degrading metabolism. The study will be applied to the site of Brescia-Caffaro, one of the largest sites in Europe contaminated by polychlorinated biphenyls (PCBs). The project aims to sort out the time-spatial synergistic interplay within the plant holobiont components and the geochemistry of rhizosphere micro-niches supporting microbial degradation. The research will combine the: i) set up and application of bacterial biosensors to examine topology and dynamics of activation of the PCB degradation pathways upon stimulation by identified plant root exudates; and ii) sensing the plant modulated chemical micro-habitats through microsensor/sensor devices during plant-microbe interaction under PCBs stress. The project outcomes will provide a comprehensive understanding of the plant holobiont applied to environmental biotechnology, focusing on the the role of root exudates as boost of soil microbiome degradative potential. Acknowledgments: This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement N° 841317.

Rhizo-remediation is a promising technology for pollutant clean-up provided by the plant holobiont, composed by the host plant and the root-associated microbiome. Through root exudation, the plant nurtures and shape the structure and functionality of the microbial communities inhabiting the root system. The complex interactions between the plant host and the microbiome are poorly understood, in particular in contaminated environments where the pollution stress may induce specific root exudation profiles that could have a role in the activation of the microbial degrading metabolism. This is particularly relevant for highly phytotoxic and poorly degradable pollutants, like polychlorinated biphenyls, a class of 209 recalcitrant congeners containing biphenyl with one up to ten chlorine atoms. The project aims to investigate the involvement of flavonoids, plant secondary metabolites, in supporting the bacterial PCB degradation and other functional traits that are important for the rhizocompetence, to investigate the changes in root chemistry upon PCB stress and sort out the time-spatial synergistic interplay within the plant holobiont components. The project outcomes will improve the understanding of the plant holobiont system applied to environmental biotechnology, focusing on the role of root exudates to boost soil microbiome degradative potential. Acknowledgments: This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement N° 841317

Background: Rhizo-remediation is a promising technology for pollutant clean-up provided by the plant holobiont, composed by the host plant and the root-associated microbiome. Through root exudation, the plant nurtures and shape the structure and functionality of the microbial communities inhabiting the root system. The complex interactions between the plant host and the microbiome are poorly understood, in particular in contaminated environments where the pollution stress may induce specific root exudation profiles that could have a role in the activation of the microbial degrading metabolism. This is particularly relevant for highly phytotoxic and poorly degradable pollutant, like polychlorinated biphenyls, a class of 209 recalcitrant congeners containing biphenyl with one up to ten chlorine atoms. Objectives. The project aims to: i) verify the changes in root chemistry upon PCBs stress; ii) sort out the time-spatial synergistic interplay within the plant holobiont components and iii) investigate the geochemistry of rhizosphere micro-niches supporting microbial degradation. Methods: The project spans metabolomics, bioengineering of microbial strains to generate bacterial biosensors to examine topology and dynamics of activation of the PCB degradation pathways upon stimulation by identified plant root exudates; and the application of microsensor devices to profile the chemistry of the root microenvironments. Results: The project outcomes will improve the understanding of the plant holobiont system applied to environmental biotechnology, focusing on the role of root exudates to boost soil microbiome degradative potential. Acknowledgments: This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement N° 841317.

Introduction: Phyto-rhyzo-remediation is a promising technology for pollutant clean-up provided by the plant holobiont, composed by the host plant and its microbiota. Plant root exudation is modulated by the pollution stress and has a key role in the activation of the microbial degrading metabolism. Despite the well documented role of the plant holobiont in ecosystem services, the complex interactions between host and microbiome are poorly understood, in particular in contaminated environments. Materials and Methods: The project will span metabolomics, bioengineering of microbial strains together with an original application of microsensor/sensor devices to profile the chemistry of the root microenvironments. The study will be applied to the site of Brescia-Caffaro, one of the largest sites in Europe contaminated by polychlorinated biphenyls (PCBs). Results: The project aims to sort out the time-spatial synergistic interplay within the plant holobiont components and the geochemistry of rhizosphere micro-niches supporting microbial degradation. The research will combine the: i) set up and application of bacterial biosensors to examine topology and dynamics of activation of the PCB degradation pathways upon stimulation by identified plant root exudates; and ii) sensing the plant modulated chemical micro-habitats through microsensor/sensor devices during plant-microbe interaction under PCBs stress. Conclusions: The project outcomes will provide a comprehensive understanding of the plant holobiont applied to environmental biotechnology, focusing on the the role of root exudates as boost of soil microbiome degradative potential. Acknowledgments: This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement N° 841317.

Plants communicate with microorganisms by exchanging chemical signals throughout the phytosphere. Such interactions are important not only for plant productivity and fitness, but also for terrestrial ecosystem functioning. It is known that beneficial microorganisms emit diffusible substances including volatile organic compounds (VOCs) that promote growth. Consistently, soil application of cell-free culture filtrates (CF) of beneficial soil and plant-associated microorganisms enhances plant growth and yield. However, how this treatment acts in plants and whether it alters the resident soil microbiota, are largely unknown. In this work we characterized the responses of pepper (Capsicum annuum L.) plants cultured under both greenhouse and open field conditions and of soil microbiota to soil application of CFs of beneficial and phytopathogenic fungi. To evaluate the contribution of VOCs occurring in the CFs to these responses, we characterized the responses of plants and of soil microbiota to application of distillates (DE) of the fungal CFs. CFs and their respective DEs contained the same potentially biogenic VOCs, and application of these extracts enhanced root growth and fruit yield, and altered the nutritional characteristics of fruits. High-throughput amplicon sequencing of bacterial 16S and fungal ITS rRNA genes of the soil microbiota revealed that the CF and DE treatments altered the microbial community compositions, and led to strong enrichment of the populations of the same beneficial bacterial and fungal taxa. Our findings show that CFs of both beneficial and phytopathogenic fungi can be used as biostimulants, and provide evidence that VOCs occurring in the fungal CFs act as mediators of the plants' responses to soil application of fungal CFs through stimulation of the beneficial soil microbiota. ; This work was supported by the Agencia Estatal de Investigación (AEI) and Fondo Europeo de Desarrollo Regional (Spain) (grants BIO2013-49125-C2-1-P, BIO2016-78747-P, and PID2019-104685GB-100), the Government of Navarra (refs. P1044 AGROESTI, P1004 PROMEBIO, and P1046 MICROBIOME), and the project "Plants as a tool for sustainable global development" (registration number: CZ.02.1.01/0.0/0.0/16_019/0000827) within the program Research, Development and Education (OP RDE). ; Peer reviewed

Plants communicate with microorganisms by exchanging chemical signals throughout the phytosphere. Such interactions are important not only for plant productivity and fitness, but also for terrestrial ecosystem functioning. It is known that beneficial microorganisms emit diffusible substances including volatile organic compounds (VOCs) that promote growth. Consistently, soil application of cell-free culture filtrates (CF) of beneficial soil and plant-associated microorganisms enhances plant growth and yield. However, how this treatment acts in plants and whether it alters the resident soil microbiota, are largely unknown. In this work we characterized the responses of pepper (Capsicum annuum L.) plants cultured under both greenhouse and open field conditions and of soil microbiota to soil application of CFs of beneficial and phytopathogenic fungi. To evaluate the contribution of VOCs occurring in the CFs to these responses, we characterized the responses of plants and of soil microbiota to application of distillates (DE) of the fungal CFs. CFs and their respective DEs contained the same potentially biogenic VOCs, and application of these extracts enhanced root growth and fruit yield, and altered the nutritional characteristics of fruits. High-throughput amplicon sequencing of bacterial 16S and fungal ITS rRNA genes of the soil microbiota revealed that the CF and DE treatments altered the microbial community compositions, and led to strong enrichment of the populations of the same beneficial bacterial and fungal taxa. Our findings show that CFs of both beneficial and phytopathogenic fungi can be used as biostimulants, and provide evidence that VOCs occurring in the fungal CFs act as mediators of the plants' responses to soil application of fungal CFs through stimulation of the beneficial soil microbiota. ; This work was supported by the Agencia Estatal de Investigación (AEI) and Fondo Europeo de Desarrollo Regional (Spain) (grants BIO2013-49125-C2-1-P, BIO2016-78747-P, and PID2019-104685GB-100), the Government of Navarra (refs. P1044 AGROESTI, P1004 PROMEBIO, and P1046 MICROBIOME), and the project "Plants as a tool for sustainable global development" (registration number: CZ.02.1.01/0.0/0.0/16_019/0000827) within the program Research, Development and Education (OP RDE).

The possibility of using microbiological indicators of soil «health» to assess the soils. Th e fundamental possibility of quantitative characterization of the functional potential of the microbial system with the assessment of «ecological services» is shown. Thermodynamic criteria of natural microbial system (exergy and specific exergy) allow to carry out diagnostics of soil condition with direct estimation of degradation and damage. System characteristics of soil microbiota allow to approach the solution of many topical problems of functional soil science.

The reuse of treated wastewater, in particular for irrigation, is an increasingly common practice, encouraged by governments and official entities worldwide. Irrigation with wastewater may have implications at two different levels: alter the physicochemical and microbiological properties of the soil and/or introduce and contribute to the accumulation of chemical and biological contaminants in soil. The first may affect soil productivity and fertility; the second may pose serious risks to the human and environmental health. The sustainable wastewater reuse in agriculture should prevent both types of effects, requiring a holistic and integrated risk assessment. In this article we critically review possible effects of irrigation with treated wastewater, with special emphasis on soil microbiota. The maintenance of a rich and diversified autochthonous soil microbiota and the use of treated wastewater with minimal levels of potential soil contaminants are proposed as sine qua non conditions to achieve a sustainable wastewater reuse for irrigation. ; info:eu-repo/semantics/acceptedVersion

Soil degradation affects more than 52 million ha of land in counties of the European Union. This problem is particularly serious in Mediterranean areas, where the effects of anthropogenic activities (tillage on slopes, deforestation, and pasture production) add to problems caused by prolonged periods of drought and intense and irregular rainfall. Soil microbiota can be used as an indicator of the soil healthy in degraded areas. This is because soil microbiota participates in the cycle elements and in the organic matter decomposition. All this helps to the young plants establishment and in long term protect the soils against the erosion. During dry periods in the Mediterranean areas, the lack of water entering the soil matrix leads to a loss of soil microbiological activity and it turns into a lower soil production capabilities. Under these conditions, the aim of this study was to evaluate the positive effect on soil biological components produced by an hydro absorbent polymer (Terracottem). The aim of the experiment was to evaluate the impact assessment of an hydropolymer (Terracottem) on the soil biological components. An experimental flowerpot layout was established in June 2015 and 12 variants with different amount of Terracottem were applied as follow: i) 3.0 kg.m3 ; ii) 1.5 kg.m3 and; iii) 0 kg.m3. In all the variants were tested the further additives: a) 1% of glucose, b) 50 kg N.ha-1 of Mineral nitrogen, c) 1% of Glucose + 50 kg N.ha-1 of Mineral nitrogen d) control (no additive). According to natural conditions, humidity have been kept at 15% in all the variants. During four weeks, mineral nitrogen leaching and soil respiration have been measured in each flowerplot. Respiration has been quantified four times every time while moistening containers and alkaline soda lime has been used as a sorbent. The amount of CO 2 increase has been measured with the sorbent. Leaching of mineral nitrogen has been quantified by ion exchange resins (IER). IER pouches have been placed on the bottom of each container, and after ...

11 páginas, 6 figuras, 2 tablas ; Alpine treelines are expected to shift upward due to climate warming, whereas warmer conditions can have negative impacts on forests located near the xeric, equatorward limit of the distribution of tree species (rear edge). We compare tree populations forming the distribution limits of mountain pine (Pinus uncinata) in north-eastern Spain: two cold-limited alpine treeline populations, and a rear-edge drought-prone stand. In the treelines, trees were sampled in three altitudinal belts to evaluate within-site variations considering the forest, the transitional ecotone and the treeline. Tree growth was markedly higher in one of the treeline sites (Tesso), particularly in the forest belt, as compared to the other treeline (Las Cutas), and to the warmest rear-edge stand. Tree growth in the rear-edge population depended on June precipitation. Trees presented also comparatively smaller leaves with higher Specific Leaf Area (SLA) there than in the two treelines. Regarding the differences between altitudinal belts within the treelines, treeline soils showed lower N concentrations and a lower content of sand than in forests. Soil microbiota was dominated by bacteria in the treeline and by fungi in the forest, although with differences between sites. Soil characteristics and microbial composition were strongly related, whereas its relationship with tree growth and functional traits was less clear. The marked differences in leaf traits and growth response to climate found when comparing treeline and rear-edge sites highlights the biogeographical uniqueness of sites forming the equatorward distribution limit. The greater tree growth in the Tesso treeline as compared to Las Cutas indicate that interactions between climate and physical and chemical properties of the soil influence tree growth and its interactions with soil microbial communities in the treeline. A better understanding of plant-soil feedbacks may help to understand the future dynamics of tree populations forming the species' climatic and geographic limits of distribution. ; This study was supported by projects: LMP242_18 (Gobierno de Aragón co-financed by FEDER European Funds), FORMAL (ref. RTI2018–096884-B-C31; Spanish Ministry of Science, Innovation and Universities) and the project "CLU-2019–05 – IRNASA/CSIC Unit of Excellence", funded by the Junta de Castilla y León and cofinanced by the European Union (ERDF "Europe drives our growth"). We acknowledge the E-OBS dataset from the EU-FP6 project UERRA (http://www.uerra.eu) and the Copernicus Climate Change Service, and the data providers in the ECA&D project (https://www.ecad.eu). The authors thank Virginia Gascón (IRNASA-CSIC) for her valuable task in laboratory analyses ; Peer reviewed

The aim of the study was comparative evaluation of microbiological processes occurring in the soil and rhizosphere during the soybean cultivation in the conditions of short-term rotation with the use of different fertilizer systems. Methods.The content of ammoniating, amylolytic, pedotrophic, oligotrophic, asporousmicroorganisms, and micromycetes was determined. The soil and rhizosphere microbiological processes were characterized by mineralization – immobilization, oligotrophism, and pedotrophism coefficients. The use of ecological and biological fertilizer systems was accompanied by the increase of ammoniating microorganisms in the soybean budding phase. The use of exclusively mineral fertilizers of soybean has only significantly increased the development of microorganisms which use nitrogen of mineral compounds. The number of oligotrophic microorganisms was the highest, indicating that the stocks of readily available nutrients were depleted and that humification processes were intensified. For the ecological system of fertilizers, the coefficient of nitrogen mineralization-immobilization was 0.72-0.83, and for the biological system was the lowest 0.60-0.99. It confirms the equilibrium of the processes of mineralization and immobilization. The oligotrophic coefficients for the ecological and biological fertilizer systems at the stages of budding and browning of beans indicate the good availability of soil microbiota with easily digestible organic substances. The use of an ecological fertilizer system with a balanced combination of mineral and organic fertilizers and a biological fertilizer system with modern organic fertilizers and humates increases the activity of soil microbiota and improves the processes of organic compound transformation.