26 research outputs found
Rate of severe and fatal infections in a cohort of patients with interstitial lung disease associated with rheumatoid arthritis: a multicenter prospective study
ObjectiveTo describe severe infection, foci of infection, microorganisms, associated factors, and impact on mortality in patients with rheumatoid arthritis–associated interstitial lung disease (RA-ILD).Patients and methodsThe study was based on a multicenter prospective cohort of patients with RA-ILD followed up from 2015 to 2023. The main outcome measures were incident severe infection and fatal infection. We evaluated infectious foci, etiologic agents, vaccination status, variables associated with lung function, and clinical-therapeutic variables in RA. The incidence rate (IR) for infection and mortality was calculated per 100 person-years, and 3 multivariate models were constructed to explore factors associated with infection.ResultsWe followed up 148 patients with RA-ILD for a median 56.7 months (699.3 person-years). During this period, 142 patients (96%) had at least 1 infection. A total of 368 infectious episodes were recorded, with an IR of 52.6 per 100 person-years. Of the 48 patients who died, 65% did so from infection. Respiratory infections were the most common first infection (74%), infection overall (74%), and fatal infection (80%) and were caused mostly by SARS CoV-2, Streptococcus pneumoniae, Pseudomonas aeruginosa, and influenza A virus. The factors associated with an increased risk of infection and death in patients with RA-ILD were age, inflammatory activity, and therapy with corticosteroids and immunosuppressants.ConclusionPatients with RA-ILD have a high risk of serious infection, especially respiratory infection. Infection develops early, is recurrent, and is frequently fatal. The presence of associated factors such as advanced age, joint inflammation, and treatment highlight the importance of integrated and preventive medical care
Detailed stratified GWAS analysis for severe COVID-19 in four European populations
Given the highly variable clinical phenotype of Coronavirus disease 2019 (COVID-19), a deeper analysis of the host genetic contribution to severe COVID-19 is important to improve our understanding of underlying disease mechanisms. Here, we describe an extended genome-wide association meta-analysis of a well-characterized cohort of 3255 COVID-19 patients with respiratory failure and 12 488 population controls from Italy, Spain, Norway and Germany/Austria, including stratified analyses based on age, sex and disease severity, as well as targeted analyses of chromosome Y haplotypes, the human leukocyte antigen region and the SARS-CoV-2 peptidome. By inversion imputation, we traced a reported association at 17q21.31 to a ~0.9-Mb inversion polymorphism that creates two highly differentiated haplotypes and characterized the potential effects of the inversion in detail. Our data, together with the 5th release of summary statistics from the COVID-19 Host Genetics Initiative including non-Caucasian individuals, also identified a new locus at 19q13.33, including NAPSA, a gene which is expressed primarily in alveolar cells responsible for gas exchange in the lung.S.E.H. and C.A.S. partially supported genotyping through a philanthropic donation. A.F. and D.E. were supported by a grant from the German Federal Ministry of Education and COVID-19 grant Research (BMBF; ID:01KI20197); A.F., D.E. and F.D. were supported by the Deutsche Forschungsgemeinschaft Cluster of Excellence ‘Precision Medicine in Chronic Inflammation’ (EXC2167). D.E. was supported by the German Federal Ministry of Education and Research (BMBF) within the framework of the Computational Life Sciences funding concept (CompLS grant 031L0165). D.E., K.B. and S.B. acknowledge the Novo Nordisk Foundation (NNF14CC0001 and NNF17OC0027594). T.L.L., A.T. and O.Ö. were funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation), project numbers 279645989; 433116033; 437857095. M.W. and H.E. are supported by the German Research Foundation (DFG) through the Research Training Group 1743, ‘Genes, Environment and Inflammation’. L.V. received funding from: Ricerca Finalizzata Ministero della Salute (RF-2016-02364358), Italian Ministry of Health ‘CV PREVITAL’—strategie di prevenzione primaria cardiovascolare primaria nella popolazione italiana; The European Union (EU) Programme Horizon 2020 (under grant agreement No. 777377) for the project LITMUS- and for the project ‘REVEAL’; Fondazione IRCCS Ca’ Granda ‘Ricerca corrente’, Fondazione Sviluppo Ca’ Granda ‘Liver-BIBLE’ (PR-0391), Fondazione IRCCS Ca’ Granda ‘5permille’ ‘COVID-19 Biobank’ (RC100017A). A.B. was supported by a grant from Fondazione Cariplo to Fondazione Tettamanti: ‘Bio-banking of Covid-19 patient samples to support national and international research (Covid-Bank). This research was partly funded by an MIUR grant to the Department of Medical Sciences, under the program ‘Dipartimenti di Eccellenza 2018–2022’. This study makes use of data generated by the GCAT-Genomes for Life. Cohort study of the Genomes of Catalonia, Fundació IGTP (The Institute for Health Science Research Germans Trias i Pujol) IGTP is part of the CERCA Program/Generalitat de Catalunya. GCAT is supported by Acción de Dinamización del ISCIII-MINECO and the Ministry of Health of the Generalitat of Catalunya (ADE 10/00026); the Agència de Gestió d’Ajuts Universitaris i de Recerca (AGAUR) (2017-SGR 529). M.M. received research funding from grant PI19/00335 Acción Estratégica en Salud, integrated in the Spanish National RDI Plan and financed by ISCIII-Subdirección General de Evaluación and the Fondo Europeo de Desarrollo Regional (European Regional Development Fund (FEDER)-Una manera de hacer Europa’). B.C. is supported by national grants PI18/01512. X.F. is supported by the VEIS project (001-P-001647) (co-funded by the European Regional Development Fund (ERDF), ‘A way to build Europe’). Additional data included in this study were obtained in part by the COVICAT Study Group (Cohort Covid de Catalunya) supported by IsGlobal and IGTP, European Institute of Innovation & Technology (EIT), a body of the European Union, COVID-19 Rapid Response activity 73A and SR20-01024 La Caixa Foundation. A.J. and S.M. were supported by the Spanish Ministry of Economy and Competitiveness (grant numbers: PSE-010000-2006-6 and IPT-010000-2010-36). A.J. was also supported by national grant PI17/00019 from the Acción Estratégica en Salud (ISCIII) and the European Regional Development Fund (FEDER). The Basque Biobank, a hospital-related platform that also involves all Osakidetza health centres, the Basque government’s Department of Health and Onkologikoa, is operated by the Basque Foundation for Health Innovation and Research-BIOEF. M.C. received Grants BFU2016-77244-R and PID2019-107836RB-I00 funded by the Agencia Estatal de Investigación (AEI, Spain) and the European Regional Development Fund (FEDER, EU). M.R.G., J.A.H., R.G.D. and D.M.M. are supported by the ‘Spanish Ministry of Economy, Innovation and Competition, the Instituto de Salud Carlos III’ (PI19/01404, PI16/01842, PI19/00589, PI17/00535 and GLD19/00100) and by the Andalussian government (Proyectos Estratégicos-Fondos Feder PE-0451-2018, COVID-Premed, COVID GWAs). The position held by Itziar de Rojas Salarich is funded by grant FI20/00215, PFIS Contratos Predoctorales de Formación en Investigación en Salud. Enrique Calderón’s team is supported by CIBER of Epidemiology and Public Health (CIBERESP), ‘Instituto de Salud Carlos III’. J.C.H. reports grants from Research Council of Norway grant no 312780 during the conduct of the study. E.S. reports grants from Research Council of Norway grant no. 312769. The BioMaterialBank Nord is supported by the German Center for Lung Research (DZL), Airway Research Center North (ARCN). The BioMaterialBank Nord is member of popgen 2.0 network (P2N). P.K. Bergisch Gladbach, Germany and the Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases, University of Cologne, Cologne, Germany. He is supported by the German Federal Ministry of Education and Research (BMBF). O.A.C. is supported by the German Federal Ministry of Research and Education and is funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy—CECAD, EXC 2030–390661388. The COMRI cohort is funded by Technical University of Munich, Munich, Germany. This work was supported by grants of the Rolf M. Schwiete Stiftung, the Saarland University, BMBF and The States of Saarland and Lower Saxony. K.U.L. is supported by the German Research Foundation (DFG, LU-1944/3-1). Genotyping for the BoSCO study is funded by the Institute of Human Genetics, University Hospital Bonn. F.H. was supported by the Bavarian State Ministry for Science and Arts. Part of the genotyping was supported by a grant to A.R. from the German Federal Ministry of Education and Research (BMBF, grant: 01ED1619A, European Alzheimer DNA BioBank, EADB) within the context of the EU Joint Programme—Neurodegenerative Disease Research (JPND). Additional funding was derived from the German Research Foundation (DFG) grant: RA 1971/6-1 to A.R. P.R. is supported by the DFG (CCGA Sequencing Centre and DFG ExC2167 PMI and by SH state funds for COVID19 research). F.T. is supported by the Clinician Scientist Program of the Deutsche Forschungsgemeinschaft Cluster of Excellence ‘Precision Medicine in Chronic Inflammation’ (EXC2167). C.L. and J.H. are supported by the German Center for Infection Research (DZIF). T.B., M.M.B., O.W. und A.H. are supported by the Stiftung Universitätsmedizin Essen. M.A.-H. was supported by Juan de la Cierva Incorporacion program, grant IJC2018-035131-I funded by MCIN/AEI/10.13039/501100011033. E.C.S. is supported by the Deutsche Forschungsgemeinschaft (DFG; SCHU 2419/2-1).Peer reviewe
Detailed stratified GWAS analysis for severe COVID-19 in four European populations
Given the highly variable clinical phenotype of Coronavirus disease 2019 (COVID-19), a deeper analysis of the host genetic contribution to severe COVID-19 is important to improve our understanding of underlying disease mechanisms. Here, we describe an extended GWAS meta-analysis of a well-characterized cohort of 3,260 COVID-19 patients with respiratory failure and 12,483 population controls from Italy, Spain, Norway and Germany/Austria, including stratified analyses based on age, sex and disease severity, as well as targeted analyses of chromosome Y haplotypes, the human leukocyte antigen (HLA) region and the SARS-CoV-2 peptidome. By inversion imputation, we traced a reported association at 17q21.31 to a highly pleiotropic ∼0.9-Mb inversion polymorphism and characterized the potential effects of the inversion in detail. Our data, together with the 5th release of summary statistics from the COVID-19 Host Genetics Initiative, also identified a new locus at 19q13.33, including NAPSA, a gene which is expressed primarily in alveolar cells responsible for gas exchange in the lung.Andre Franke and David Ellinghaus were supported by a grant from the German
Federal Ministry of Education and Research (01KI20197), Andre Franke, David
Ellinghaus and Frauke Degenhardt were supported by the Deutsche
Forschungsgemeinschaft Cluster of Excellence “Precision Medicine in Chronic
Inflammation” (EXC2167). David Ellinghaus was supported by the German Federal
Ministry of Education and Research (BMBF) within the framework of the
Computational Life Sciences funding concept (CompLS grant 031L0165). David
Ellinghaus, Karina Banasik and Søren Brunak acknowledge the Novo Nordisk
Foundation (grant NNF14CC0001 and NNF17OC0027594). Tobias L. Lenz, Ana
Teles and Onur Özer were funded by the Deutsche Forschungsgemeinschaft (DFG,
German Research Foundation), project numbers 279645989; 433116033; 437857095. Mareike Wendorff and Hesham ElAbd are supported by the German
Research Foundation (DFG) through the Research Training Group 1743, "Genes,
Environment and Inflammation". This project was supported by a Covid-19 grant from
the German Federal Ministry of Education and Research (BMBF; ID: 01KI20197).
Luca Valenti received funding from: Ricerca Finalizzata Ministero della Salute RF2016-02364358, Italian Ministry of Health ""CV PREVITAL – strategie di prevenzione
primaria cardiovascolare primaria nella popolazione italiana; The European Union
(EU) Programme Horizon 2020 (under grant agreement No. 777377) for the project
LITMUS- and for the project ""REVEAL""; Fondazione IRCCS Ca' Granda ""Ricerca
corrente"", Fondazione Sviluppo Ca' Granda ""Liver-BIBLE"" (PR-0391), Fondazione
IRCCS Ca' Granda ""5permille"" ""COVID-19 Biobank"" (RC100017A). Andrea Biondi
was supported by the grant from Fondazione Cariplo to Fondazione Tettamanti: "Biobanking of Covid-19 patient samples to support national and international research
(Covid-Bank). This research was partly funded by a MIUR grant to the Department of
Medical Sciences, under the program "Dipartimenti di Eccellenza 2018–2022". This
study makes use of data generated by the GCAT-Genomes for Life. Cohort study of
the Genomes of Catalonia, Fundació IGTP. IGTP is part of the CERCA Program /
Generalitat de Catalunya. GCAT is supported by Acción de Dinamización del ISCIIIMINECO and the Ministry of Health of the Generalitat of Catalunya (ADE 10/00026);
the Agència de Gestió d’Ajuts Universitaris i de Recerca (AGAUR) (2017-SGR 529).
Marta Marquié received research funding from ant PI19/00335 Acción Estratégica en
Salud, integrated in the Spanish National RDI Plan and financed by ISCIIISubdirección General de Evaluación and the Fondo Europeo de Desarrollo Regional
(FEDER-Una manera de hacer Europa").Beatriz Cortes is supported by national
grants PI18/01512. Xavier Farre is supported by VEIS project (001-P-001647) (cofunded by European Regional Development Fund (ERDF), “A way to build Europe”).
Additional data included in this study was obtained in part by the COVICAT Study
Group (Cohort Covid de Catalunya) supported by IsGlobal and IGTP, EIT COVID-19
Rapid Response activity 73A and SR20-01024 La Caixa Foundation. Antonio Julià
and Sara Marsal were supported by the Spanish Ministry of Economy and
Competitiveness (grant numbers: PSE-010000-2006-6 and IPT-010000-2010-36).
Antonio Julià was also supported the by national grant PI17/00019 from the Acción
Estratégica en Salud (ISCIII) and the FEDER. The Basque Biobank is a hospitalrelated platform that also involves all Osakidetza health centres, the Basque government's Department of Health and Onkologikoa, is operated by the Basque
Foundation for Health Innovation and Research-BIOEF. Mario Cáceres received
Grants BFU2016-77244-R and PID2019-107836RB-I00 funded by the Agencia Estatal
de Investigación (AEI, Spain) and the European Regional Development Fund
(FEDER, EU). Manuel Romero Gómez, Javier Ampuero Herrojo, Rocío Gallego Durán
and Douglas Maya Miles are supported by the “Spanish Ministry of Economy,
Innovation and Competition, the Instituto de Salud Carlos III” (PI19/01404,
PI16/01842, PI19/00589, PI17/00535 and GLD19/00100), and by the Andalussian
government (Proyectos Estratégicos-Fondos Feder PE-0451-2018, COVID-Premed,
COVID GWAs). The position held by Itziar de Rojas Salarich is funded by grant
FI20/00215, PFIS Contratos Predoctorales de Formación en Investigación en Salud.
Enrique Calderón's team is supported by CIBER of Epidemiology and Public Health
(CIBERESP), "Instituto de Salud Carlos III". Jan Cato Holter reports grants from
Research Council of Norway grant no 312780 during the conduct of the study. Dr.
Solligård: reports grants from Research Council of Norway grant no 312769. The
BioMaterialBank Nord is supported by the German Center for Lung Research (DZL),
Airway Research Center North (ARCN). The BioMaterialBank Nord is member of
popgen 2.0 network (P2N). Philipp Koehler has received non-financial scientific grants
from Miltenyi Biotec GmbH, Bergisch Gladbach, Germany, and the Cologne
Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases,
University of Cologne, Cologne, Germany. He is supported by the German Federal
Ministry of Education and Research (BMBF).Oliver A. Cornely is supported by the
German Federal Ministry of Research and Education and is funded by the Deutsche
Forschungsgemeinschaft (DFG, German Research Foundation) under Germany's
Excellence Strategy – CECAD, EXC 2030 – 390661388. The COMRI cohort is funded
by Technical University of Munich, Munich, Germany. Genotyping was performed by
the Genotyping laboratory of Institute for Molecular Medicine Finland FIMM
Technology Centre, University of Helsinki. This work was supported by grants of the
Rolf M. Schwiete Stiftung, the Saarland University, BMBF and The States of Saarland
and Lower Saxony. Kerstin U. Ludwig is supported by the German Research
Foundation (DFG, LU-1944/3-1). Genotyping for the BoSCO study is funded by the
Institute of Human Genetics, University Hospital Bonn. Frank Hanses was supported
by the Bavarian State Ministry for Science and Arts. Part of the genotyping was
supported by a grant to Alfredo Ramirez from the German Federal Ministry of Education and Research (BMBF, grant: 01ED1619A, European Alzheimer DNA
BioBank, EADB) within the context of the EU Joint Programme – Neurodegenerative
Disease Research (JPND). Additional funding was derived from the German Research
Foundation (DFG) grant: RA 1971/6-1 to Alfredo Ramirez. Philip Rosenstiel is
supported by the DFG (CCGA Sequencing Centre and DFG ExC2167 PMI and by SH
state funds for COVID19 research). Florian Tran is supported by the Clinician Scientist
Program of the Deutsche Forschungsgemeinschaft Cluster of Excellence “Precision
Medicine in Chronic Inflammation” (EXC2167). Christoph Lange and Jan Heyckendorf
are supported by the German Center for Infection Research (DZIF). Thorsen Brenner,
Marc M Berger, Oliver Witzke und Anke Hinney are supported by the Stiftung
Universitätsmedizin Essen. Marialbert Acosta-Herrera was supported by Juan de la
Cierva Incorporacion program, grant IJC2018-035131-I funded by
MCIN/AEI/10.13039/501100011033. Eva C Schulte is supported by the Deutsche
Forschungsgemeinschaft (DFG; SCHU 2419/2-1).N
Arable Weed Patterns According to Temperature and Latitude Gradient in Central and Southern Spain
(1) Background: In agro-ecosystems, the success of the crops has a strong connection to biodiversity in the landscape. In the face of climate change, it is important to understand the response to environmental variation of weed species by means of their distribution. In the last century, biodiversity has been impacted due to a variety of stresses related to climate change. Although the composition of vegetation tends to change at a slower rate than climate change, we hypothesize species present in weed communities are distributed in diverse patterns as a response to the climate. Therefore, the general aim of this paper is to investigate the effect of temperature, using latitude as an indicator, on the composition and distribution of weed communities in agro-ecosystems. (2) Methods: Weeds were monitored in georeferenced cereal fields which spanned south and central Spanish regions. The graphic representation according to latitude allowed us to identify groups of weeds and associate them to a temperature range. We classified weeds as generalist, regional, or local according to the range of distribution. (3) Results: The monitoring of species led to the classification of weeds as generalist, regional or local species according to latitude and associated temperature ranges. Three weed species that were present in all latitude/temperature regions, were classified as generalist (Linaria micrantha (Cav) Hoffmanns & Link, Sonchus oleraceous L., and Sysimbrium irium L.). The species were classified as regional or local when their presence was limited to restricted latitude/temperature ranges. One weed, Stellaria media (L.) Vill., was considered a local species and its distribution dynamics can be considered an indicator of temperature. (4) Conclusions: The novel methodology used in this study to assign weed distribution as an indicator of climatic conditions could be applied to evaluate climate gradients around the world
Influencia de las condiciones climáticas en el banco de semillas del suelo y en la flora arvense emergida en un sistema de rotación cerealista de secano en dos localidades diferentes
El término “banco de semillas del suelo” se utiliza para definir el reservorio constituido por todas las semillas, frutos y fragmentos de fruto viables (es decir, con capacidad de germinar) presentes en el suelo o sobre su superficie con capacidad para regenerar la comunidad vegetal en diferentes periodos de tiempo dependiendo de si las semillas se encuentran durmientes o no. Representa la flora potencial de un lugar y es particularmente importante en hábitats profundamente perturbados como los agroecosistemas, siendo la causa de las sucesivas reinfestaciones de los cultivos. La composición del banco de semillas y de la flora real están condicionados por los factores edafo climáticos, así como por el manejo del cultivo y del suelo. Conocer su composición y su dinámica son aspectos claves para la gestión de los cultivos y para la evaluación del posible éxito o fracaso de las técnicas de control implementadas. El objetivo general de la presente Tesis es conocer el efecto de las condiciones medioambientales y de manejo sobre los bancos de semillas y la flora real arvense de dos agroecosistemas cerealistas mediterráneos situados en el centro y sur peninsular. El material objeto de análisis de este trabajo se obtuvo a partir de muestras del banco de semillas de los ensayos de Madrid y de Sevilla durante un periodo de 3 años. El estudio de la evolución de los bancos de semillas y de la flora real se llevó a cabo en función de las condiciones meteorológicas (reflejadas por los años), las condiciones edáficas (representadas por las localidades) y 4 rotaciones distintas. La cuantificación del banco de semillas del suelo se realizó mediante las metodologías de extracción y germinación. Paralelamente, se cuantificó e identificó la flora real y se analizó la correlación existente entre ambas poblaciones (flora potencia y flora real). Además, se evaluó la incidencia, sobre la evolución de la densidad y biodiversidad en ambas poblaciones, de las variables año, localidad y cultivo. Completando estos estudios con un análisis de la similaridad de las poblaciones y un análisis de redes, que proporcionó la integración global, de forma gráfica, de todas las variables estudiadas, y su evolución en el tiempo, tanto en el banco de semillas como en la flora real. Los resultados obtenidos en la cuantificación de semillas del suelo mediante las metodologías de extracción y germinación, mostraron diferencias significativas de tipo cuantitativo pero no de tipo cualitativo, recomendándose la metodología de germinación en estudios relacionados con la flora real, o a corto-plazo, y el de extracción en estudios de resiliencia de las poblaciones. Los factores que generan estas diferencias incluyen las características morfológicas de las semillas o frutos, así como la existencia de mecanismos de dormición, afectados por las condiciones medioambientales. La flora potencial y flora real al inicio del ensayo, se vieron muy afectadas por la intensidad del manejo inmediatamente anterior al inicio de los experimentos. Dicha intensidad de manejo, también condicionó la dinámica tanto del banco de semillas como de la flora en sentido inverso en las dos localidades de estudio, en función del tiempo, en un caso disminuyendo (Madrid) y en otro aumentando (Sevilla). En relación a la incidencia de la climatología, se detectaron comportamientos con diferencias significativas en las poblaciones, densidades e índices de biodiversidad (índices de Shannon, Simpson, Pielou y Margalef) en función de la localidad y de la rotación. Con relación a los cultivos, en las condiciones en las que se han desarrollado los ensayos; el análisis de los datos demuestra que el cultivo que más incidió en el control de malas hierbas fue en ambos casos el de cebada seguido, en función de la localidad, de trigo (Madrid) y colza (Sevilla). Todos los datos obtenidos se integraron para el análisis de similaridad (índices de Jaccard y Sorensen), observándose la evolución en el tiempo de la relación entre flora real y flora potencial. Aunque se observó una relación muy pobre, aumentó con el paso del tiempo si bien existieron diferencias significativas entre localidades. En Madrid, la similaridad entre la flora potencial y real fue inferior a la observada en Sevilla. Para concluir el estudio el análisis de redes mostró las relaciones multifactoriales establecidas en la distribución de las especies tanto del banco de semillas como de la flora real. Complementando los aspectos científicos de esta Tesis Doctoral, se desarrolló un equipo para aumentar la eficiencia del proceso de extracción de semillas, en la actualidad presentado como solicitud de patente industrial. ----------ABSTRACT---------- The term "soil seed bank" is used to define the reservoir consisting of all viable seeds, fruits and fruit fragments (with ability to germinate) present in or on the soil, and with the capacity to regenerate the plant community in different time periods depending on whether the seeds are dormant or not. It represents the potential flora of a site, and is particularly important in deeply disturbed habitats such as agroecosystems, being the cause of successive crop re-infestations. The composition of the seed bank and the “emerging flora” are conditioned by soil and climatic factors, as well as by crop and soil management. Knowing their composition and dynamics are key aspects for crop management and for evaluating the possible success or failure of any control techniques implemented. The general objective of this Thesis is to determine the effect of environmental and management conditions on seed banks, and the emerging flora of two Mediterranean cereal agroecosystems located in the centre and south of the Iberian Peninsula. The material to be analysed in this work was obtained from seed bank samples from Madrid and Seville trials, over a period of 3 years. The study of the evolution of the seed banks and the emerging flora was carried out according to the meteorological conditions (reflected by the years), the edaphic conditions (represented by the localities) and 4 different rotations. Quantification of the soil seed bank was carried out using extraction and germination methodologies. At the same time, the emerging flora was quantified and identified and the correlation between both populations (potential and emerging flora) was analysed. In addition, the incidence of the variables year, locality and crop on the evolution of density and biodiversity, in both populations, was evaluated. These studies were completed analysing the similarity of the populations and a network analysis, which provided the global integration, in a graphic way, of all the variables studied, and their time evolution both in the seed bank and in the emerging flora. The results obtained from the quantification of soil seed banks using the extraction and germination methodologies showed significant differences (quantitative in terms of seed density) and not qualitative (in terms of species number). As a result, the germination methodology is recommended for studies related to the emerging flora, or in the short term, and the extraction methodology in resilience studies of populations. Factors that generate these differences include the morphological characteristics of the seeds or fruits, as well as the existence of dormancy mechanisms affected by environmental conditions. The potential and emerging flora at the beginning of the trials were strongly affected by the intensity of management immediately prior to their start point. This management intensity also conditioned the dynamics of both the seed bank and the flora, which were the opposite in the two sites, depending on the time, in one case decreasing (Madrid) and in the other increasing (Seville). In relation to the climatic influence, significant differences were detected in the populations, densities and biodiversity indices (Shannon, Simpson, Pielou and Margalef indices) depending on the year, the locality and the rotation. With regard to the crops, under the conditions in which the trials were carried out, the analysis of the data showed that the crop with the greatest impact on weed control, in both cases, was barley, followed by wheat (Madrid) and rapeseed (Seville), depending on the locality. All data obtained were integrated for similarity analysis (Jaccard and Sorensen indices), observing the changes in the relationships between emerging flora and potential flora over time. Although, a very poor relationship was observed, it increased over time, with significant differences between localities. In Madrid, the similarity between potential and emerging flora was lower than in Seville. To conclude the study, network analysis showed all multifactorial relationships between the species distribution in the seed bank and the emerging flora. Adding to the scientific aspects of this Doctoral Thesis, an equipment was developed to increase the efficiency of the seed extraction process, which is currently being presented as an industrial patent application
Cuadernos de pedagogía
Resumen tomado de la publicaciónMonográfico con el título: “Educar para la igualdad de género”Este centro trabaja los valores mediante la elaboración de materiales audiovisuales y su posterior análisis. La colaboración entre el alumnado, profesorado, comunidad educativa y municipios da lugar a vídeos muy significativos, mediante los cuales se busca fomentar la igualdad, la paz y la integración, y luchar contra la violencia de género.Biblioteca de Educación del Ministerio de Educación, Cultura y Deporte; Calle San Agustín, 5 - 3 planta; 28014 Madrid; Tel. +34917748000; [email protected]
Efficiency of Methodologies Used in the Evaluation of the Weed Seed Bank under Mediterranean Conditions
The objective of this study was to compare the efficiency of two methodologies, seed germination (SG) and seed physical extraction SPE), to assess the weed community from two locations with different soil and climatic conditions: M, with dry and low soil fertility, and S with high soil humidity and fertility. Over three years of study, the analysis of both methodologies confirmed differences in seed bank composition. In M, fewer seeds were recorded by SG than SPE (13.5% and 86.5% respectively), while in S, the difference between percentages was less (31.58% by SG and 68.41% by SPE). Our findings confirmed that Portulaca oleracea L., Amaranthus blitoides S. Watson and Chenopodium album L. were abundantly found in M. Anacyclus clavatus (Def.) Res. seeds were also found, mainly detected by SG. In S, Stellaria media (L.) Vill. was widely found. All species found in S were similarly detected by SG and SPE. The results confirmed that climatic and soil conditions influenced the efficiency of the methodology used to assess the seed bank. M conditions led to an increased seed reservoir, and both methodologies were necessary to obtain the seed bank composition. In S conditions, the seed bank was continuously renewed, and either one of methodologies defined the seed bank composition equally well
The influence of rainfall and tillage on wheat yield parameters and weed population in monoculture versus rotation systems
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Departamento de Medio Ambiente y Agronomía (INIA)Extreme climate events (ECEs) of drought are becoming common in Mediterranean areas and farmers need adapt agricultural practices to achieve sustainability. This field study took place in to gain insight into the effects of seasonal rainfall, tillage and crop systems on wheat yield and weed parameters. Conventional (CT), minimum (MT) and no-tillage (NT) systems in wheat monoculture and rotation cropping systems were tested during 3 years of study (2014-2015, 2015-2016 and 2016-2017). Growing Season Rainfall (GSR) was the most influential factor on yield parameters and weed population. In 2016-2017, categorized as an extreme climate event by drought, the GSR accounted for 43.4% of the historical average. This year, the wheat yield (373 kg ha-1) and harvest index (0.18) were the lowest. In 2015-2016, scarcer autumn rainfall (44 mm) affected the weed germination period, reducing the density (17 plants m-2) and diversity of weed species (3 species m-2) while yield was favoured by high winter and spring rainfall (247 mm). Our study revealed that tillage effects was not significant on wheat yield, but NT systems consistently showed higher weed density and diversity than CT and MT despite the irregular GSR during this study. The rotation system presented higher values of wheat grain yield (781 kg/ha) and dry straw biomass (1803 kg/ha) but also weed biomass (48.54 g m-2) compared to monoculture (27.50 g m-2). NT and rotation combined increased the weed community although did not reduce the wheat yield compare to conventional systems even with an ECE of drought.This work has been funded by Project RTA 2017-00006-C03-01 (Spanish Ministry of Science and Innovation). All authors have contributed significantly, and all authors are in agreement with the content of the manuscript. We confirm that this work is original and has not been published elsewhere, nor is it currently under consideration for publication elsewhere. We have no conflicts of interest to disclose. The datasets analysed during the current study are available from the corresponding author on reasonable request.Peer reviewe
Effects of tillage systems on wheat and weed water relationships over time when growing together, in semiarid conditions
10 Pág.Water availability directly influences interactions and competition between weeds and crops. This article is based on the idea that relative water content (RWC) indicates the water uptake within plants and that it is possible to explain the water relationships between plants that are growing together. A field experiment carried out for 3 years (2013–2014, 2014–2015 and 2015–2016) compared the short-term effects of years and tillage systems on wheat grain yield, weed density, wheat-RWC, weed-RWC and soil water content (SWC), at tillering and flowering stages in a winter wheat monoculture system. The three tillage treatments were conventional tillage (CT), minimum tillage (MT) and no-tillage (NT). Wheat grain yield was low all years of study, because of low interannual rainfall, and we did not observe differences between tillage systems. Weed density was also affected by year and not by tillage systems. Lowest winter rainfall (73.4 mm from Nov to Feb) in the last year of the study (2015–2016), decreased the weed density in all tillage systems. Despite the rainfall variability over the 3 years of study, the NT system presented higher weed density (73 plants/m2) than MT and CT systems (39.83 and 46.33 plants/m2). We also observed a higher number of weed species for the NT system, facilitated by a high soil water storage in this system. The wheat-RWC, at tillering stage, varied with years and tillage systems; we found that high winter rainfall (2013–2014) led to higher values in CT (64.5%) compared with MT (52.9%) and NT plots (52.9%). Weed-RWC values did not vary and SWC was greater in NT than in CT and MT. At flowering stage, the year (2015–2016) with highest spring rainfall favoured higher wheat-RWC in NT (56.9%) compared with CT (48.3%). However, the lowest spring rainfall coincided with the lowest weed-RWC, (18% in NT plots) and SWC was always higher in NT soils. The results showed that climatic conditions affected the water competence dynamics between weeds and wheat in different ways. Seemingly, weeds can tolerate a lack of water availability until crop tillering stage independently of tillage system; however, the competition for water was not a problem as crops overcame the high weed density by flowering stage.This work has been funded by projects AT2017-003 and RTA2017-00006-C03-01 (Spanish Ministry of Science and Innovation).Peer reviewe