FungalRoot Soudzilovskaia, Nadejda A.; Vaessen, Stijn; Barcelo, Milagros ...
The New phytologist,
August 2020, Letnik:
227, Številka:
3
Journal Article
Recenzirano
Odprti dostop
• Testing of ecological, biogeographical and phylogenetic hypotheses of mycorrhizal traits requires a comprehensive reference dataset about plant mycorrhizal associations.
• Here we present a ...database, FungalRoot, which summarizes publicly available data about vascular plant mycorrhizal type and intensity of root colonization by mycorrhizal fungi, accompanied with rich metadata. We compiled and digitized data about plant mycorrhizal colonization in nine widespread languages.
• The present version of the FungalRoot database contains 36 303 species-by-site observations for 14 870 plant species, tripling the previously available compiled information about plant mycorrhizal associations. Based on these data, we provide a recommended list of genuslevel plant mycorrhizal associations, based on the majority of data for species and careful analysis of conflicting data. The majority of ectomycorrhizal and ericoid mycorrhizal plants are trees (92%) and shrubs (85%), respectively. The majority of arbuscular and nonmycorrhizal plant species are herbaceous (50% and 70%, respectively).
• Our publicly available database is a powerful resource for mycorrhizal scientists and ecologists. It features possibilities for dynamic updating and addition of data about plant mycorrhizal associations. The new database will promote research on plant and fungal biogeography and evolution, and on links between above- and belowground biodiversity and ecosystem functioning.
Summary
The intestinal tract of mammals is colonized by a large number of microorganisms including trillions of bacteria that are referred to collectively as the gut microbiota. These indigenous ...microorganisms have co‐evolved with the host in a symbiotic relationship. In addition to metabolic benefits, symbiotic bacteria provide the host with several functions that promote immune homeostasis, immune responses, and protection against pathogen colonization. The ability of symbiotic bacteria to inhibit pathogen colonization is mediated via several mechanisms including direct killing, competition for limited nutrients, and enhancement of immune responses. Pathogens have evolved strategies to promote their replication in the presence of the gut microbiota. Perturbation of the gut microbiota structure by environmental and genetic factors increases the risk of pathogen infection, promotes the overgrowth of harmful pathobionts, and the development of inflammatory disease. Understanding the interaction of the microbiota with pathogens and the immune system will provide critical insight into the pathogenesis of disease and the development of strategies to prevent and treat inflammatory disease.
Successful establishment of plants is limited by both biotic and abiotic conditions and their interactions. Seedling establishment is also used as a direct measure of habitat suitability, but ...transient changes in vegetation might provide windows of opportunity allowing plant species to colonize sites which otherwise appear unsuitable. We aimed to study spatio-temporal variability in the effects of resident vegetation on establishment, growth and reproduction of dry grassland species in abandoned arable fields representing potentially suitable habitats. Seeds were sown in disturbed (bare of vegetation and roots) and undisturbed plots in three fields abandoned in the last 20 years. To assess the effects of temporal variation on plant establishment, we initiated our experiments in two years (2007 and 2008). Seventeen out of the 35 sown species flowered within two years after sowing, while three species completely failed to become established. The vegetation in the undisturbed plots facilitated seedling establishment only in the year with low spring precipitation, and the effect did not hold for all species. In contrast, growth and flowering rate were consistently much greater in the disturbed plots, but the effect size differed between the fields and years of sowing. We show that colonization is more successful when site opening by disturbance coincide with other suitable conditions such as weather or soil characteristics. Seasonal variability involved in our study emphasizes the necessity of temporal replication of sowing experiments. Studies assessing habitat suitability by seed sowing should either involve both vegetation removal treatments and untreated plots or follow the gradient of vegetation cover. We strongly recommend following the numbers of established individuals, their sizes and reproductive success when assessing habitat suitability by seed sowing since one can gain completely different results in different phases of plant life cycle.
The Hellenistic West Prag, Jonathan R. W; Quinn, Josephine Crawley
10/2013
eBook
Although the Hellenistic period has become increasingly popular in research and teaching in recent years, the western Mediterranean is rarely considered part of the 'Hellenistic world'; instead the ...cities, peoples and kingdoms of the West are usually only discussed insofar as they relate to Rome. This book contends that the rift between the 'Greek East' and the 'Roman West' is more a product of the traditional separation of Roman and Greek history than a reflection of the Hellenistic-period Mediterranean, which was a strongly interconnected cultural and economic zone, with the rising Roman republic just one among many powers in the region, east and west. The contributors argue for a dynamic reading of the economy, politics and history of the central and western Mediterranean beyond Rome, and in doing so problematise the concepts of 'East', 'West' and 'Hellenistic' itself.
A colonização da África teve impactos profundos para as populações colonizadas e foi um elemento crucial para a constituição dos Estados africanos no período pós-colonização. Tendo isso em vista, o ...artigo tem como objetivo analisar como se deu e quais os impactos da colonização do continente africano. Através de uma revisão bibliográfica de fontes primárias e secundárias, argumentase que a colonização se instituiu através tanto da imposição de uma estrutura de pensamento pautada na hierarquização de populações tendo como base preceitos raciais, quanto pelo interesse de exploração de recursos a partir do domínio do território. Ademais, concluise que a colonização delimitou as condições de possibilidade dos Estados africanos no pós-colonização em suas formas de organização política e social.
Summary Natural regeneration of farmland areas following landuse change has the potential to reinstate native vegetation and landscape processes across larger scales than intentional works. However, ...few examples of large-scale natural regeneration have been reported from southern Australia. In this study we use historical air photos to document the rate of establishment of natural regeneration in central Victoria following a change from agricultural to rural residential land use. In 2009, regrowth patches occupied 8185ha, or 12.3% of the cleared landscape in the study region, mostly on relatively low fertility soils. Most of this area (6216ha) supported Cassinia shrubland, with eucalypts encroaching as patches get older. On average, native vegetation has regenerated over nearly 1800ha every decade since the mid-1960s. If this trend continues, regrowth will occupy 20% of infertile soils on private land by 2025. This region now appears to support one of the largest examples of old field succession recorded from south-eastern Australia. Regrowth patches are likely to provide many conservation benefits, although little information exists on habitat values provided by regrowth shrublands. Since regeneration is on private land, perceptions of whether regrowth is 'good' or 'bad' will vary according to landholder goals, as will future management of regrowth patches. Consequently, considerable ecological and social research is required to understand the ecosystem services and disservices which regrowth provides to both landholders and biota.
It has typically been assumed that habitat destruction, characterized by habitat loss and fragmentation, has consistently negative effects on biodiversity. While numerous empirical studies have shown ...the detrimental effects of habitat loss, debate continues as to whether habitat fragmentation has universally negative effects. To explore the effects of habitat fragmentation, we developed a simple model for site‐occupancy dynamics in fragmented landscapes. With the model, we demonstrate that a competition–colonization trade‐off can result in nonlinear oscillatory responses in biodiversity to both habitat loss and fragmentation. However, the overall pattern of habitat loss reducing species richness is still established, in line with empirical observations. Interestingly, the existence of localized oscillations in biodiversity can explain the mixed responses of species richness to habitat fragmentation per se observed in nature, thereby reconciling the debate on the fragmentation–diversity relationship. Therefore, this study offers a parsimonious mechanistic explanation for empirically observed biodiversity patterns in response to habitat destruction.
This book analyses the laws that shaped modern European empires from medieval times to the twentieth century. Its geographical scope is global, including the Americas, Europe, Africa, Asia, Australia ...and the Poles. Andrew Fitzmaurice focuses upon the use of the law of occupation to justify and critique the appropriation of territory. He examines both discussions of occupation by theologians, philosophers and jurists, as well as its application by colonial publicists and settlers themselves. Beginning with the medieval revival of Roman law, this study reveals the evolution of arguments concerning the right to occupy through the School of Salamanca, the foundation of American colonies, seventeenth-century natural law theories, Enlightenment philosophers, eighteenth-century American colonies and the new American republic, writings of nineteenth-century jurists, debates over the carve up of Africa, twentieth-century discussions of the status of Polar territories, and the period of decolonisation.
Inflammation of the uterine environment (commonly as a result of microbial colonisation of the fetal membranes, amniotic fluid and fetus) is strongly associated with preterm labour and birth. Both ...preterm birth and fetal inflammation are independently associated with elevated risks of subsequent short- and long-term respiratory, gastro-intestinal and neurological complications. Despite numerous clinical and experimental studies to investigate localised and systemic fetal inflammation following exposure to microbial agonists, there is minimal data to describe which fetal organ(s) drive systemic fetal inflammation. We used lipopolysaccharide (LPS) from E.coli in an instrumented ovine model of fetal inflammation and conducted a series of experiments to assess the systemic pro-inflammatory capacity of the three major fetal surfaces exposed to inflammatory mediators in pregnancy (the lung, gastro-intestinal tract and skin/amnion). Exposure of the fetal lung and fetal skin/amnion (but not gastro-intestinal tract) caused a significant acute systemic inflammatory response characterised by altered leucocytosis, neutrophilia, elevated plasma MCP-1 levels and inflammation of the fetal liver and spleen. These novel findings reveal differential fetal organ responses to pro-inflammatory stimulation and shed light on the pathogenesis of fetal systemic inflammation after exposure to chorioamnionitis.
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