Search results for "DIR"
showing 10 items of 10242 documents
Is legal protection sufficient to ensure plant conservation? The Italian Red List of policy species as a case study
2015
AbstractThe conservation of species listed in the Bern Convention and European Directive 1992/43/EEC (so-called policy species) is mandatory for European Union (EU) countries. We assessed the conservation status of Italian policy species, based on the IUCN categories and criteria, to evaluate the effectiveness of existing protection measures at the national level. Among the 203 vascular plants, bryophytes and lichens evaluated, 41.9% are categorized as threatened, and one is already extinct, indicating that the protection measures for policy species are inadequate. Our results for the Italian policy species are consistent with those of an assessment at the EU level. Conservation priorities …
Spatial monitoring of gene activity in extraradical and intraradical developmental stages of arbuscular mycorrhizal fungi by direct fluorescent in si…
2008
International audience; Gene expression profiling based on tissue extracts gives only limited information about genes associated with complex developmental processes such as those implicated in fungal interactions with plant roots during arbuscular mycorrhiza development and function. To overcome this drawback, a direct fluorescent in situ RT-PCR methodology was developed for spatial mapping of gene expression in different presymbiotic and symbiotic structures of an arbuscular mycorrhizal fungus. Transcript detection was optimized by targeting the LSU rRNA gene of Glomus intraradices and monitoring expression of a stearoyl-CoA-desaturase gene that is consistently expressed at high levels in…
Negative frequency-dependent selection of sexually antagonistic alleles in Myodes glareolus.
2011
Sexually antagonistic genetic variation, where optimal values of traits are sex-dependent, is known to slow the loss of genetic variance associated with directional selection on fitness-related traits. However, sexual antagonism alone is not sufficient to maintain variation indefinitely. Selection of rare forms within the sexes can help to conserve genotypic diversity. We combined theoretical models and a field experiment with Myodes glareolus to show that negative frequency-dependent selection on male dominance maintains variation in sexually antagonistic alleles. In our experiment, high-dominance male bank voles were found to have low-fecundity sisters, and vice versa. These results show …
Rapid assessment of female preference for male size predicts subsequent choice of spawning partner in a socially monogamous cichlid fish.
2011
5 pages; International audience; Although size-assortative mating in convict cichlids, Amatitliana nigrofasciata, is supposed to result from mutual mating preference for larger individuals, female choice in relation to male size remains ambiguous. We revisited the evidence for directional preference for larger males in female convict cichlids using a classical two-way choice apparatus in which each female could decide to spend time in front of a small male or a large one. We found evidence for female preference for large males, as assessed from association preference during a 4-hour period following encounter. Furthermore, females decided to spawn in front of the initially preferred male mo…
Novel Wood Resistance Measurement Method Reducing the Initial Transient Instabilities Arising in DC Methods Due to Polarization Effects
2019
A novel method for measuring the electrical resistance in wood is presented. It is based on applying an Alternating Current (AC) to two electrodes rammed into the wood. The method reduces the transient time for value stabilization. In case of Direct Current (DC) resistance measurement methods, typically used in wood measurement, an initial transient exists, invalidating the measured value during an initial transient period. This measurement method uses an electronic circuit based on a relaxation oscillator where the wood automatically sets the oscillation frequency depending on its electrical resistance. Compared to other AC methods, this circuit greatly simplifies the measurement process, …
Empirical Bayes improves assessments of diversity and similarity when overdispersion prevails in taxonomic counts with no covariates
2019
Abstract The assessment of diversity and similarity is relevant in monitoring the status of ecosystems. The respective indicators are based on the taxonomic composition of biological communities of interest, currently estimated through the proportions computed from sampling multivariate counts. In this work we present a novel method to estimate the taxonomic composition able to work even with a single sample and no covariates, when data are affected by overdispersion. The presence of overdispersion in taxonomic counts may be the result of significant environmental factors which are often unobservable but influence communities. Following the empirical Bayes approach, we combine a Bayesian mo…
Behaviour of consumers of conventional and organic flowers and ornamental plants in Italy
2013
The paper analyses preferences and motivations of Italian consumers of flowers and ornamental plants, both conventional and organic. The results helped to outline their profile. Purchases are still done in the traditional places (flower shops for cut flowers and plant nurseries for potted plants), however positive trend is found for potted plants purchases at large distribution chains. Some differences came out as to purchase motivations: cut flowers are mainly bought in special occasions whereas potted plants purchases are linked to personal use. The results confirm a positive relationship between the purchase of flowers and plants and the age of the interviewees, besides showing that wome…
Conservation implications of change in antipredator behavior in fragmented habitat: Boreal rodent, the bank vole, as an experimental model
2015
Abstract Habitat fragmentation is known to cause population declines but the mechanisms leading to the decline are not fully understood. Fragmentation is likely to lead to changes in predation risk, which may cause behavioral responses with possible population level consequences. It has recently been shown that the awareness of predator presence, resulting in a fear response, strongly affects behavior and physiology of the prey individuals. Costs arising from fear may be as important for the prey population size as the direct killing of prey. We tested how predation risk in the form of scent of a specialist predator, the least weasel (Mustela nivalis nivalis), affects bank vole (Myodes glar…
Viral fitness determines the magnitude of transcriptomic and epigenomic reprograming of defense responses in plants
2020
Although epigenetic factors may influence the expression of defense genes in plants, their role in antiviral responses and the impact of viral adaptation and evolution in shaping these interactions are still poorly explored. We used two isolates of turnip mosaic potyvirus with varying degrees of adaptation to Arabidopsis thaliana to address these issues. One of the isolates was experimentally evolved in the plant and presented increased load and virulence relative to the ancestral isolate. The magnitude of the transcriptomic responses was larger for the evolved isolate and indicated a role of innate immunity systems triggered by molecular patterns and effectors in the infection process. Sev…
Implications of the EFSA Scientific Opinion on Site Directed Nucleases 1 and 2 for Risk Assessment of Genome-Edited Plants in the EU
2021
Genome editing is a set of techniques for introducing targeted changes in genomes. It may be achieved by enzymes collectively called site-directed nucleases (SDN). Site-specificity of SDNs is provided either by the DNA binding domain of the protein molecule itself or by RNA molecule(s) that direct SDN to a specific site in the genome. In contrast to transgenesis resulting in the insertion of exogenous DNA, genome editing only affects specific endogenous sequences. Therefore, multiple jurisdictions around the world have exempted certain types of genome-edited organisms from national biosafety regulations completely, or on a case-by-case basis. In the EU, however, the ruling of the Court of J…