Suchergebnisse

This dissertation makes an overview of the process of regionalization in the Spanish autonomous community of Extremadura in the last 30 years. We explore concepts of region, regionalism and regionalization within a common European framework and within the theories of the New Regionalism in Europe. This paper studies the decentralization process in Spain after the promulgation of the 1978 Constitution, analysing the position and role of Extremadura in that process. Likewise we analyse the role of the so-called Historical Regions in the decentralization process and the creation of Autonomous Communities. We observe some of the regional policies of the European Union in its attempt to create a polycentric network for development where economic and social cohesion are the main premises, promoting diversity as an engine of development and unity. It also embraces highly contested concepts in the social sciences as globalization and regional identities. We addressed the role of regions as autonomous entities in the European Union and on a global space. Likewise approach the capacity for action and cooperation of the regions and their outward promotion. The aim of this dissertation is to try to analyse the influence that the three main factors may have in the process of regionalization of Extremadura. Spanish decentralization process and the creation of Autonomous Communities; the influence of regionalist policies of the European Union in the region concept and its constitution as a protagonist in territorial cohesion policies; and the effects of globalization on local spaces and resurgence of the region and regionalist identities. ; Esta dissertação faz uma visão geral do processo de regionalização na comunidade autónoma espanhola da Extremadura, nos últimos 30 anos. Nós exploramos conceitos de região, o regionalismo ea regionalização dentro de um quadro europeu comum e dentro das teorias do Novo Regionalismo na Europa. Este trabalho estuda o processo de descentralização na Espanha após a promulgação da Constituição de 1978, analisando a posição eo papel da Extremadura nesse processo. Da mesma forma, analisamos o papel das chamadas regiões históricas no processo de descentralização ea criação de Comunidades Autónomas. Observamos algumas das políticas regionais da União Europeia, na sua tentativa de criar uma rede policêntrica de desenvolvimento, onde a coesão económica e social são os principais locais, promovendo a diversidade como um motor de desenvolvimento e de união. Ele abarca também conceitos altamente contestadas nas ciências sociais como a globalização e as identidades regionais. Abordamos o papel das regiões como entidades autônomas na União Europeia e num espaço global. Da mesma forma abordar a capacidade de ação e cooperação das regiões e da sua promoção externa. O objetivo deste trabalho é tentar analisar a influência que os três fatores principais podem ter no processo de regionalização da Extremadura. Processo Espanhol descentralização ea criação de comunidades autónomas, a influência das políticas regionalistas da União Europeia no conceito de região e sua constituição como protagonista nas políticas de coesão territorial, e os efeitos da globalização sobre os espaços locais e ressurgimento da região e identidades regionalistas.

14 páginas, 1 tablas, 4 figuras ; Trifolium rubens L. is a leguminous plant "Preferential Attention", according to the Catalog of Protected Flora of Castile and Leon (Spain). In this study we aimed to analyze the potential of three bacterial strains of the genus Rhizobium to improve the growth and development of this plant. All three strains produced 3-indoleacetic acid (IAA), but the strain ATCC 14480 produced the most. In addition, all strains produced biofilms and cellulases, although in different quantities. The synthesis of these products has been described as being related to the processes of the adherence of bacteria to the plant root surface and their entrance into the plant, respectively. In addition, in vitro assays and assays conducted under controlled and sterile conditions were performed, showing that the three strains were capable of nodulating T. rubens L. and effectively fixed nitrogen for the plant. These results were corroborated by morphological and histological analysis of nodules. Finally, greenhouse assays determined the effects of the strains under more competitive conditions, and it was concluded that inoculated plants presented greater lengths and weights, both aerial and radicular, and also chlorophyll and nitrogen content compared to the uninoculated controls. ; This work was supported by Grants SA169 U 14 from Junta de Castilla y León (Spanish Regional Government) and AGL2015-70510-R from MINECO (Central Spanish Government). We thank Emma-Jane Keck form the Central Language Service of the University of Salamanca for the English revision. XCG received a fellowship from Kinesis Foundation from Puerto Rico. ; Peer reviewed

Primary infection of legumes by rhizobia involves the controlled localized enzymatic breakdown of cell walls at root hair tips. Previous studies determined the role of rhizobial CelC2 cellulase in different steps of the symbiotic interaction Rhizobium leguminosarum-Trifolium repens. Recent findings also showed that CelC2 influences early signalling events in the Ensifer meliloti-Medicago truncatula interaction. Here, we have monitored the root hair phenotypes of two legume plants, T. repens and M. sativa, upon inoculation with strains of their cognate and non-cognate rhizobial species, R. leguminosarum bv trifolii and E. meliloti, (over)expressing the CelC2 coding gene, celC. Regardless of the host, CelC2 specifically elicited 'hole-on-the-tip' events (Hot phenotype) in the root hair apex, consistent with the role of this endoglucanase in eroding the noncrystalline cellulose found in polarly growing cell walls. Overproduction of CelC2 also increased root hair tip redirections (RaT phenotype) events in both cognate and non-cognate hosts. Interestingly, heterologous celC expression also induced non-canonical alterations in ROS (Reactive Oxygen Species) homeostasis at root hair tips of Trifolium and Medicago. These results suggest the concurrence of shared unspecific and host-related plant responses to CelC2 during early steps of symbiotic rhizobial infection. Our data thus identify CelC2 cellulase as an important determinant of events underlying early infection of the legume host by rhizobia. ; This work was supported by Grant AGL2015-70510-R from MINECO (Spanish Ministry of Economy, Industry and Competitiveness). E.M. and M.R. were supported by PhD fellowships from the Spanish government.

10 páginas, 4 figuras y 2 tablas ; The growing interest in a healthy lifestyle and in environmental protection is changing habits regarding food consumption and agricultural practices. Good agricultural practice is indispensable, particularly for raw vegetables, and can include the use of plant probiotic bacteria for the purpose of biofertilization. In this work we analysed the probiotic potential of the rhizobial strain PEPV40, identified as Rhizobium laguerreae through the analysis of the recA and atpD genes, on the growth of spinach plants. This strain presents several in vitro plant growth promotion mechanisms, such as phosphate solubilisation and the production of indole acetic acid and siderophores. The strain PEPV40 produces cellulose and forms biofilms on abiotic surfaces. GFP labelling of this strain showed that PEPV40 colonizes the roots of spinach plants, forming microcolonies typical of biofilm initiation. Inoculation with this strain significantly increases several vegetative parameters such as leaf number, size and weight, as well as chlorophyll and nitrogen contents. Therefore, our findings indicate, for the first time, that Rhizobium laguerreae is an excellent plant probiotic, which increases the yield and quality of spinach, a vegetable that is increasingly being consumed raw worldwide. ; This work was supported by Grants SA169U14 and SA058U16 from the Regional Government of Castile and Leon, and AGL2015–70510-R from MINECO (Spanish Ministry of Economy, Industry and Competitiveness). AJG is the recipient of a FPU predoctoral fellowship from the Central Spanish Government, JDFF is the recipient of a predoctoral fellowship from Salamanca University. PGF receives funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No. 750795. The authors also thank Emma Keck, translator at the Language Centre of the University of Salamanca. ; Peer reviewed

10 páginas, 4 figuras, 2 tablas.-- The first publication is available at https://www.nature.com ; The growing interest in a healthy lifestyle and in environmental protection is changing habits regarding food consumption and agricultural practices. Good agricultural practice is indispensable, particularly for raw vegetables, and can include the use of plant probiotic bacteria for the purpose of biofertilization. In this work we analysed the probiotic potential of the rhizobial strain PEPV40, identified as Rhizobium laguerreae through the analysis of the recA and atpD genes, on the growth of spinach plants. This strain presents several in vitro plant growth promotion mechanisms, such as phosphate solubilisation and the production of indole acetic acid and siderophores. The strain PEPV40 produces cellulose and forms biofilms on abiotic surfaces. GFP labelling of this strain showed that PEPV40 colonizes the roots of spinach plants, forming microcolonies typical of biofilm initiation. Inoculation with this strain significantly increases several vegetative parameters such as leaf number, size and weight, as well as chlorophyll and nitrogen contents. Therefore, our findings indicate, for the first time, that Rhizobium laguerreae is an excellent plant probiotic, which increases the yield and quality of spinach, a vegetable that is increasingly being consumed raw worldwide. ; This work was supported by Grants SA169U14 and SA058U16 from the Regional Government of Castile and Leon, and AGL2015–70510-R from MINECO (Spanish Ministry of Economy, Industry and Competitiveness).AJG is the recipient of a FPU predoctoral fellowship from the Central Spanish Government, JDFF is the recipient of a predoctoral fellowship from Salamanca University. PGF receives funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No. 750795. The authors also thank Emma Keck, translator at the Language Centre of the University of Salamanca. ; Peer reviewed

36 páginas, 6 tablas, 6 figuras ; Rapeseed (Brassica napus L.) is an important crop worldwide, due to its multiple uses, such as a human food, animal feed and a bioenergetic crop. Traditionally, its cultivation is based on the use of chemical fertilizers, known to lead to several negative effects on human health and the environment. Plant growth-promoting bacteria may be used to reduce the need for chemical fertilizers, but efficient bacteria in controlled conditions frequently fail when applied to the fields. Bacterial endophytes, protected from the rhizospheric competitors and extreme environmental conditions, could overcome those problems and successfully promote the crops under field conditions. Here, we present a screening process among rapeseed bacterial endophytes to search for an efficient bacterial strain, which could be developed as an inoculant to biofertilize rapeseed crops. Based on in vitro, in planta, and in silico tests, we selected the strain Pseudomonas brassicacearum CDVBN10 as a promising candidate; this strain produces siderophores, solubilizes P, synthesizes cellulose and promotes plant height in 5 and 15 days-post-inoculation seedlings. The inoculation of strain CDVBN10 in a field trial with no addition of fertilizers showed significant improvements in pod numbers, pod dry weight and shoot dry weight. In addition, metagenome analysis of root endophytic bacterial communities of plants from this field trial indicated no alteration of the plant root bacterial microbiome; considering that the root microbiome plays an important role in plant fitness and development, we suggest this maintenance of the plant and its bacterial microbiome homeostasis as a positive result. Thus, Pseudomonas brassicacearum CDVBN10 seems to be a good biofertilizer to improve canola crops with no addition of chemical fertilizers; this the first study in which a plant growth-promoting (PGP) inoculant specifically designed for rapeseed crops significantly improves this crop's yields in field conditions. ; This research was funded by EUROPEAN UNION'S HORIZON 2020 research and innovation programme, grant number 750795. AJG is the recipient of a FPU predoctoral fellowship from the Central Spanish Government and ZSS received a grant from the Junta de Castilla y Leon, Spanish Regional Government. EM acknowledges a FCT contract from the Individual Call to Scientific Employment Stimulus 2017 (CEECIND/00270/2017). ; Peer reviewed

13 páginas, 2 tablas ; A bacterial strain designated RA9T was isolated from a root of Cistus ladanifer in Spain. Phylogenetic analyses based on 16S rRNA gene sequences placed the isolate into the genus Bacillus with its closest relatives being Bacillus fortis R-6514T and Bacillus fordii R-7190T with 98.2 % similarity in both cases. DNA–DNA hybridization studies showed mean relatedness values of 29 and 30 %, respectively, between strain RA9T and the type strains of B. fortis and B. fordii. Cells of the isolate were Gram-stain-positive, motile, sporulating rods. Catalase and oxidase were positive. Gelatin, starch and casein were not hydrolysed. Menaquinone MK-7 was the only menaquinone detected and iso-C15 : 0 and anteiso-C15 : 0 were the major fatty acids. The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, one unidentified aminophospholipid, one unidentified phospholipid, one unidentifed glycolipid and one unidentified lipid. meso-Diaminopimelic acid was detected in the peptidoglycan. The DNA G+C content was 43.1 mol%. Phylogenetic, chemotaxonomic and phenotypic analyses showed that strain RA9T should be considered as representing a novel species of the genus Bacillus, for which the name Bacillus terrae sp. nov. is proposed. The type strain is RA9T (=LMG 29736T=CECT 9170T). ; This work was supported by MINECO (Spanish Central Government) grant RTC-2014-1793-2. ; Peer reviewed

Abstract Background The synthesis of cellulose is among the most important but poorly understood biochemical processes, especially in bacteria, due to its complexity and high degree of regulation. In this study, we analyzed both the production of cellulose by all known members of the Rhizobiaceae and the diversity of Rhizobium celABC operon predicted to be involved in cellulose biosynthesis. We also investigated the involvement in cellulose production and biofilm formation of celC gene encoding an endoglucanase (CelC2) that is required for canonical symbiotic root hair infection by Rhizobium leguminosarum bv. trifolii. Results ANU843 celC mutants lacking (ANU843ΔC2) or overproducing cellulase (ANU843C2+) produced greatly increased or reduced amounts of external cellulose micro fibrils, respectively. Calcofluor-stained cellulose micro fibrils were considerably longer when formed by ANU843ΔC2 bacteria rather than by the wild-type strain, in correlation with a significant increase in their flocculation in batch culture. In contrast, neither calcofluor-stained extracellular micro fibrils nor flocculation was detectable in ANU843C2+ cells. To clarify the role of cellulose synthesis in Rhizobium cell aggregation and attachment, we analyzed the ability of these mutants to produce biofilms on different surfaces. Alteration of wild-type CelC2 levels resulted in a reduced ability of bacteria to form biofilms both in abiotic surfaces and in planta. Conclusions Our results support a key role of the CelC2 cellulase in cellulose biosynthesis by modulating the length of the cellulose fibrils that mediate firm adhesion among Rhizobium bacteria leading to biofilm formation. Rhizobium cellulose is an essential component of the biofilm polysaccharidic matrix architecture and either an excess or a defect of this "building material" seem to collapse the biofilm structure. These results position cellulose hydrolytic enzymes as excellent anti-biofilm candidates. ; We thank Nancy Fujishige and Peter De Hoff for help in the biofilm assays. This work was supported by Junta de Castilla y León Grant GR49 and MICINN Grants AGL2008-03360 and AGL2011-29227. M.R. and L.R. were supported by a PhD fellowship from the Spanish government ; Peer Reviewed

24 páginas, 4 figuras, 1 tabla. -- The definitive version is available at http://www.elsevier.com ; This work was supported by JCyL (Junta de Castilla y León, Spanish Regional Government) and MICINN (Ministry of Science and Innovation, Spanish Central Government). ; Peer reviewed

11 páginas, 3 tablas, 1 figura ; Canola (Brassica napus L. var. oleracea) is the third most common oil-producing crop worldwide after palm and soybean. Canola cultivation requires the use of chemical fertilizers, but the amount required can be reduced by applying plant growth-promoting bacteria (PGPB). Among PGPB, endophytic bacteria have certain advantages as biofertilizers, but canola endophytic bacteria have rarely been studied. In this work, we identified a collection of bacterial endophytes isolated from canola roots using MALDI-TOF MS, a technique that is still rarely used for the identification of such bacteria, and rrs gene sequencing, a methodology that is commonly used to identify canola endophytes. The results demonstrated that some bacterial isolates from canola roots belonged to the genera Bacillus, Neobacillus, Peribacillus (Pe.), and Terribacillus, but most isolates belonged to the genera Paenibacillus (P.) and Pseudomonas (Ps.). Inoculation of these isolates indicated that several of them could efficiently promote canola seedling growth in hydroponic conditions. These results were then confirmed in a microcosm experiment using agricultural soil, which demonstrated that several isolates of Pseudomonas thivervalensis, Paenibacillus amylolyticus, Paenibacillus polymyxa, Paenibacillus sp. (Paenibacillus glucanolyticus/Paenibacillus lautus group), and Peribacillus simplex (previously Bacillus simplex) could efficiently promote canola shoot growth under greenhouse conditions. Among them, the isolates of Paenibacillus and Peribacillus were the most promising biofertilizers for canola crops as they are sporulated rods, which is an advantageous trait when formulating biofertilizers ; This work was supported by JCyL (Junta de Castilla y León, Spanish Regional Government) Grant SA058U16 to EMM and 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"). ; Peer reviewed

A single-layer, all-dielectric metasurface exhibiting a strong toroidal resonance in the low-atmospheric loss radio window of the subterahertz W-band is theoretically proposed and experimentally demonstrated. The metasurface is fabricated on a high-resistivity floating-zone silicon wafer by means of a single-process, wet anisotropic etching technique. The properties of the toroidal mode of both the constituent dielectric elements and the metasurface are rigorously investigated by means of the multipole decomposition technique and full-wave simulations. The experimental demonstration of such a compact, all-silicon metasurface opens new venues of research in the investigation of toroidal modes and the engineering of functional millimeter-wave components, which can be scaled to terahertz and higher frequencies of the electromagnetic spectrum. ; This work was supported by the European Union COST Action CA16220 "European Network for High Performance Integrated Microwave Photonics", by the Comunidad de Madrid and FEDER Program under grant 2018/NMT-4326, the Ministerio de Economía y Competitividad of Spain (TEC2013-47342-C2-2-R), and the mobility programs of Carlos III University and & "José Castillejo" of the Ministerio de Educación, Cultura y Deporte of Spain

10 páginas, 1 tabla, 1 figura ; The increasing interest in the preservation of the environment and the health of consumers is changing production methods and food consumption habits. Functional foods are increasingly demanded by consumers because they contain bioactive compounds involved in health protection. In this sense biofertilization using plant probiotics is a reliable alternative to the use of chemical fertilizers, but there are few studies about the effects of plant probiotics on the yield of functional fruits and, especially, on the content of bioactive compounds. In the present work we reported that a strain of genus Phyllobacterium able to produce biofilms and to colonize strawberry roots is able to increase the yield and quality of strawberry plants. In addition, the fruits from plants inoculated with this strain have significantly higher content in vitamin C, one of the most interesting bioactive compounds in strawberries. Therefore the use of selected plant probiotics benefits the environment and human health without agronomical losses, allowing the production of highly functional foods. ; This work was granted by "Junta de Castilla y León" (Regional Government, Grant SA183A11-2) and MINECO (Central Government, Grant AGL2011-29227). Paula García-Fraile is recipient of a postdoctoral researcher contract from Academy of Sciences of the Czech Republic. José David Flores-Félix was supported by a fellowship of Salamanca University. Marta Marcos García was supported by a fellowship of Fundación Miguel Casado San José. Luís R. Silva is grateful to the financial support from the European Union (FEDER funds through COMPETE) and National Funds (FCT, Fundação para a Ciência e Tecnologia) through project Pest-C/EQB/LA0006/2013 and from the European Union (FEDER funds) under the framework of QREN through Project NORTE-07-0124-FEDER- 000069. ; Peer reviewed

7 páginas, 3 tablas y 2 figuras ; The biofertilization of crops with plant-growth-promoting microorganisms is currently considered as a healthy alternative to chemical fertilization. However, only microorganisms safe for humans can be used as biofertilizers, particularly in vegetables that are raw consumed, in order to avoid sanitary problems derived from the presence of pathogenic bacteria in the final products. In the present work we showed that Rhizobium strains colonize the roots of tomato and pepper plants promoting their growth in different production stages increasing yield and quality of seedlings and fruits. Our results confirmed those obtained in cereals and alimentary oil producing plants extending the number of non-legumes susceptible to be biofertilized with rhizobia to those whose fruits are raw consumed. This is a relevant conclusion since safety of rhizobia for human health has been demonstrated after several decades of legume inoculation ensuring that they are optimal bacteria for biofertilization. ; This work was supported by Ministerio de Ciencia e Innovación (Ministry of Science and Innovation, Spanish Central Government, Grant AGL2010-17380, that includes co-financial support of Regional Development Funds, and Grant AGL2011-29227) and Junta de Castilla y León (Castilla and León Council, Spanish Regional Government, Grant SA183A11-2). Martha Helena Ramírez-Bahena is recipient of a postdoctoral researcher contract JAE-DOC from Consejo Superior de Investigaciones Científicas (Spanish National Research Council). María Teresa Fernández was supported by a fellowship of Spanish International Cooperation Agency (Spanish Central Government). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. ; Peer reviewed