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251.
The aphids Macrosiphum euphorbiae (Thomas) and Myzus persicae (Sulzer) (Hemiptera: Aphididae) are responsible for yield reduction in potato (Solanum tuberosum) production by direct phloem feeding and by spreading viruses. Breeding resistant traits from Solanum chomatophilum into the potato germplasm provides alternative means to control aphid infestations. Integrated pest management strategy, using plant resistance, benefits from the characterization of the resistance and of its impact on aphid biology. Our objective was to characterize the resistance of S. chomatophilum by assessing the effects of accessions, plant parts on aphid performance, and by assessing the impact of the resistance factors on different aphid developmental stages and on alate morph production. Detailed aphid performance was obtained by measuring fecundity, survival, percentage of nymphs that reached adult moult, and population growth using whole plant and clip cage experimental designs. Accession and plant physiological age, but not aphid developmental stage, influenced all life-history parameters, except for alate morph production which was not induced on the resistant accessions. Plant part influence was independent of plant species and accession. Both experimental designs resulted in congruent resistance levels at the accession level for each of the two aphid species, supporting the use of any of them in S. chomatophilum resistance screening. PI243340 was resistant to both aphid species, while PI365324 and PI310990 were also resistant to M. euphorbiae and M. persicae, respectively. 相似文献
252.
There is increased recognition of a common suite of global challenges that hamper food system sustainability at the community scale. Food price volatility, shortages of basic commodities, increased global rates of obesity and non-communicable food-related diseases, and land grabbing are among the impediments to socially just, economically robust, ecologically regenerative and politically inclusive food systems. While international political initiatives taken in response to these challenges (e.g. Via Campesina) and the groundswell of local alternatives emerging in response to challenges are well documented, more attention is needed to the analysis of similarities between community approaches to global pressures. While we are not suggesting the application of a template set of good practices, the research reported in this paper point to the benefits of both sharing good practices and enabling communities to adopt good practices that are suited to their place-based capacities. The work also suggests that sharing community-derived good practices can support and reinforce global networks of sustainable community food systems, foster knowledge co-creation and ultimately cement collective action to global pressures. In turn these networks could enhance the sustainability and resilience of community food systems and facilitate wide scale food system transformation. 相似文献
253.
Makoschey B Franken P Mars JM Dubois E Schroeder C Thiry J Alvarez M Rypuła K Cavirani S Arnaiz I Houtain JY Bartak P Brownlie J Wolf G Meyer G Klees W Beer M Moennig V Thiry E 《Berliner und Münchener tier?rztliche Wochenschrift》2010,123(11-12):519-21, 516-8
Control of IBR and BVD should be possible in Europe. Effective vaccines and reliable tools for monitoring are available. Systematic approach and strict implementation of control measures are essential. Voluntary or mandatory programs are ongoing on regional or national level in a lot of countries. Successful programs put pressure on surrounding regions/countries to initiate control program as well. 相似文献
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Foodborne zoonoses have a major health impact in industrialised countries. New European food safety regulations were issued to apply risk analysis to the food chain. The severity of foodborne zoonoses and the exposure of humans to biological hazards transmitted by food must be assessed. For meat, inspection at the slaughterhouse is historically the main means of control to protect consumers. However, the levels of detection of biological hazards during meat inspection have not been established in quantitative terms yet. Pork is the most frequently consumed meat in Europe. The aim of this study was to provide elements for quantifying levels of risk for pork consumers and lack of detection by meat inspection. Information concerning hazard identification and characterisation was obtained by the compilation and statistical analysis of data from 440 literature references. The incidence and severity of human cases due to pork consumption in Europe were assessed in order to calculate risk scores. A ratio of non-control was calculated for each biological hazard identified as currently established in Europe, i.e. the incidence of human cases divided by the prevalence of hazards on pork. Salmonella enterica, Yersinia enterocolitica and Campylobacter spp. were characterised by high incidence rates. Listeria monocytogenes, Clostridium botulinum and Mycobacterium spp. showed the highest severity scores. The three main high risk hazards involved in foodborne infections, Y. enterocolitica, S. enterica and Campylobacter spp. are characterised by high non-control ratios and cannot be detected by macroscopic examination of carcasses. New means of hazard control are needed to complement the classical macroscopic examination. 相似文献
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Deafness and vestibular dysfunction in a Doberman Pinscher puppy associated with a mutation in the PTPRQ gene
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Julien Dupouey Benoît Faucher Sophie Edouard Hervé Richet Angeli Kodjo Michel Drancourt Bernard Davoust 《Comparative immunology, microbiology and infectious diseases》2014
Leptospirosis has been reemerging in both developed and developing countries including Europe, where, this phenomenon has notably been associated with urban transmission. However, the comprehensive data that are needed to fully understand the ongoing epidemiological trends are lacking. In this article, we report surveillance data from throughout Europe, especially in France, to have an overview of this neglected disease in temperate countries. Our results underline the important role of wild rodents as reservoir of leptospirosis, and highlight the potential danger of a reemergence of this under-reported infectious disease in European cities, associated with the important expansion of the rat population in urban areas. 相似文献
260.
As a result of Elymus athericus (Poaceae) invasion in the last 10 years, a major change in vegetation cover has occurred in salt marshes of the Mont Saint-Michel bay (France). Such invasions are known to modify biodiversity and consequently ecosystem proprieties and functions as well as the conservation value of invaded areas. In this study, we especially focus (1) on the impact of the invasive species on the conservation value of the invaded ecosystems and (2) on the impact of mowing in the invaded parts of salt marshes. Among the various biological models, spiders were selected for the present study because they are an abundant, diversified, taxonomic group of generalist predators. Furthermore, data are available on this group since 1984, allowing a comparison of species distribution ranges in salt marshes before and after the E. athericus invasion. This diachronic approach showed that the invasion of salt marshes promoted the progression of non-coastal species, web-building spiders and cursorial spiders, but did not interfere with resident species distributions, finally resulting in higher spider densities and species richness in the entire area.The species composition, functional groups, abundances and densities of spider assemblages were also compared using complementary sampling techniques (i.e., pitfall traps, collecting by hand and quadrat technique) between natural and invaded stations in 2002 for synchronic approach. One main result is that some halophilic species decreased in abundances and densities in invaded plots, which is thought to alter the marine character of salt marsh arthropod assemblages. Lastly, mowing, by reducing non-coastal species and enhancing halophilic ones, tends to reduce the negative effects of Elymus on salt marsh conservation value. The relation between the treatments tested (invasive species and mowing) and the spider assemblages by changes in environmental variables confirms the high value of this group as bioindicators. 相似文献