Search results for "Clima"
showing 10 items of 6069 documents
Unraveling Salt Tolerance in Halophytes: A Comparative Study on Four Mediterranean Limonium Species with Different Geographic Distribution Patterns
2017
[EN] We have performed an extensive study on the responses to salt stress in four related Limonium halophytes with different geographic distribution patterns, during seed germination and early vegetative growth. The aims of the work were twofold: to establish the basis for the different chorology of these species, and to identify relevant mechanisms of salt tolerance dependent on the control of ion transport and osmolyte accumulation. Seeds were germinated in vitro, in the presence of increasing NaCl concentrations, and subjected to ¿recovery of germination¿ tests; germination percentages and velocity were determined to establish the relative tolerance and competitiveness of the four Limoni…
Maritime Pine Pinus Pinaster Aiton
2018
Maritime pine (Pinus pinaster Aiton) is the most abundant conifer in the Mediterranean basin. Currently, maritime pine is considered to be a model conifer species for study of the adaption responses to drought stress from a genomics approach. In this context, the availability of protocols that allow not only mass vegetative propagation of selected families or genotypes, but also facilitate the functional analyses needed to verify and further to study the effects of candidate genes are necessary. Here we describe an improved protocol to generate maritime pine plants through somatic embryogenesis from immature megagametophytes. Accurate procedures for explant preparation, somatic embryo induc…
Experimental approaches for testing if tolerance curves are useful for predicting fitness in fluctuating environments
2017
Most experimental studies on adaptation to stressful environments are performed under conditions that are rather constant and rarely ecologically relevant. Fluctuations in natural environmental conditions are ubiquitous and include for example variation in intensity and duration of temperature, droughts, parasite loads, and availability of nutrients, predators and competitors. The frequency and amplitude of many of these fluctuations are expected to increase with climate change. Tolerance curves are often used to describe fitness components across environmental gradients. Such curves can be obtained by assessing performance in a range of constant environmental conditions. In this perspectiv…
Little parallelism in genomic signatures of local adaptation in two sympatric, cryptic sister species.
2020
Species living in sympatry and sharing a similar niche often express parallel phenotypes as a response to similar selection pressures. The degree of parallelism within underlying genomic levels is often unexplored, but can give insight into the mechanisms of natural selection and adaptation. Here, we use multi-dimensional genomic associations to assess the basis of local and climate adaptation in two sympatric, cryptic Crematogaster levior ant species along a climate gradient. Additionally, we investigate the genomic basis of chemical communication in both species. Communication in insects is mainly mediated by cuticular hydrocarbons (CHCs), which also protect against water loss and, hence,…
Comparable response of wild rodent gut microbiome to anthropogenic habitat contamination
2021
Abstract Species identity is thought to dominate over environment in shaping wild rodent gut microbiota, but it remains unknown whether the responses of host gut microbiota to shared anthropogenic habitat impacts are species-specific or if the general gut microbiota response is similar across host species. Here, we compare the influence of exposure to radionuclide contamination on the gut microbiota of four wild mouse species: Apodemus flavicollis, A. sylvaticus, A. speciosus and A. argenteus. Building on the evidence that radiation impacts bank vole (Myodes glareolus) gut microbiota, we hypothesized that radiation exposure has a general impact on rodent gut microbiota. Because we sampled (…
Marine Cryptophytes Are Great Sources of EPA and DHA
2017
Microalgae have the ability to synthetize many compounds, some of which have been recognized as a source of functional ingredients for nutraceuticals with positive health effects. One well-known example is the long-chain polyunsaturated fatty acids (PUFAs), which are essential for human nutrition. Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are the two most important long-chain omega-3 (-3) PUFAs involved in human physiology, and both industries are almost exclusively based on microalgae. In addition, algae produce phytosterols that reduce serum cholesterol. Here we determined the growth rates, biomass yields, PUFA and sterol content, and daily gain of eight strains of marine…
Adaptation to environmental stress at different timescales
2020
Environments are changing rapidly, and to cope with these changes, organisms have to adapt. Adaptation can take many shapes and occur at different speeds, depending on the type of response, the trait, the population, and the environmental conditions. The biodiversity crisis that we are currently facing illustrates that numerous species and populations are not capable of adapting with sufficient speed to ongoing environmental changes. Here, we discuss current knowledge on the ability of animals and plants to adapt to environmental stress on different timescales, mainly focusing on thermal stress and ectotherms. We discuss within-generation responses that can be fast and induced within minute…
UV-screening and springtime recovery of photosynthetic capacity in leaves of Vaccinium vitis-idaea above and below the snow pack
2019
International audience; Evergreen plants in boreal biomes undergo seasonal hardening and dehardening adjusting their photosynthetic capacity and photoprotection; acclimating to seasonal changes in temperature and irradiance. Leaf epidermal ultraviolet (UV)-screening by flavonols responds to solar radiation, perceived in part through increased ultraviolet-B (UV-B) radiation, and is a candidate trait to provide cross-photoprotection. At Hyytiälä Forestry Station, central Finland, we examined whether the accumulation of flavonols was higher in leaves of Vaccinium vitis-idaea L. growing above the snowpack compared with those below the snowpack. We found that leaves exposed to colder temperature…
Temperature and pH define the realised niche space of arbuscular mycorrhizal fungi
2021
Made available in DSpace on 2021-06-25T11:52:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-03-04 European Regional Development Fund (Centre of Excellence EcolChange) University of Tartu (Estonian Research Council ) Moscow State University Natural Sciences and Engineering Research Council of Canada Discovery Grant Russian Science Foundation Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Swedish Research Council (Vetenskapsradet) The arbuscular mycorrhizal (AM) fungi are a globally distributed group of soil organisms that play critical roles in ecosystem function. However, the ecological niches of individual AM fungal taxa are poorly understood. We collected > 300 s…
Additive effects of temperature and infection with an acanthocephalan parasite on the shredding activity of Gammarus fossarum (Crustacea: Amphipoda):…
2017
10 pages; International audience; Climate change can have critical impacts on the ecological role of keystone species, leading to subsequent alterations within ecosystems. The consequences of climate change may be best predicted by understanding its interaction with the cumulative effects of other stressors, although this approach is rarely adopted. However, whether this interaction is additive or interactive can hardly be predicted from studies examining a single factor at a time. In particular, biotic interactions are known to induce modifications in the functional role of many species. Here, we explored the effect of temperature on leaf consumption by a keystone freshwater shredder, the …