Wild Lactuca species,their genetic diversity,resistance to diseases and pests,and exploitation in lettuce breeding

Current knowledge of wild Lactuca L. species, their taxonomy, biogeography, gene-pools, germplasm collection quality and quantity, and accession availability is reviewed in this paper. Genetic diversity of Lactuca spp. is characterized at the level of phenotypic and phenological variation, variation in karyology and DNA content, biochemical traits, and protein and molecular polymorphism. The reported variation in reaction to pathogens and pests of wild Lactuca spp. is summarized, including the viral pathogens (Lettuce mosaic virus-LMV, Mirafiori lettuce virus/Lettuce big vein virus-LBV, Beet western yellows virus-BWYV, Tomato spotted wilt virus-TSWV, Cucumber mosaic virus-CMV, Lettuce necrotic stunt virus-LNSV), bacterial pathogens (corky root-Rhizomonas suberifaciens, bacterial leaf spot-Xanthomonas campestris pv. vitians), fungal pathogens (downy mildew-Bremia lactucae, powdery mildew-Golovinomyces cichoracearum, anthracnose-Microdochium panattoniana, stemphylium leaf spot-Stemphylium spp., sclerotinia drop-Sclerotinia spp., verticillium wilt-Verticillium dahliae, fusarium wilt-Fusarium spp., pythium wilt-Pythium tracheiphylum, P. uncinulatum), nematodes (potato cyst nematode-Globodera rostochiensis, root-knot nematode-Meloidogyne spp., incognita, hapla, javanica, enterolobii), insects and mites (the green lettuce aphid-Nasonovia ribisnigri, the green peach aphid-Myzus persicae, the potato aphid-Macrosiphum euphorbiae, leafminer-Liriomyza spp., L. langei). The approaches used to exploit wild Lactuca spp. in lettuce breeding (interspecific hybridization, cell and tissue culture, transformation) are dicussed, and known examples of lettuce cultivars with traits derived from wild Lactuca spp. are described.     

Genetic diversity and connectivity patterns of harvested and aquacultured molluscs in estuaries from Asturias (northern Spain). Implications for management strategies

Estuaries are among the most important habitats of coastal areas. However, they are significantly affected by human activities worldwide, threatening their resources and the commercial uses depending on them. Fisheries and aquaculture are some of the main factors affecting the estuarine ecosystems today. In this work, we pursue the aims of genetically identifying the cultured and harvested oyster and razor clam species inhabiting Asturian estuaries (Eo, Ribadesella and Villaviciosa) and describing the genetic diversity and patterns of genetic connectivity between those species in these estuaries. The results revealed the almost complete dominance of the introduced Crassostrea gigas as the species that supports the oyster's production in Asturias with a striking diversity of gene pools in wild environments (Ría de Villaviciosa and Ribadesella) which significantly exceeds the diversity found in the hatcheries seeds commonly used for culturing. Moreover, we detected two different species of Ensis sp. inhabiting the Asturian estuaries: Ensis ensis inside Ría del Eo and Ensis directus, an invasive species, in Ría de Villaviciosa. Significant genetic differentiation between estuaries for the exotic oyster C. gigas and also for the native razor clam Solen marginatus were found. These results suggest Asturian estuaries are not a single management unit for some species and thus prevention must be taken for avoiding intentional or human‐mediated translocations among them. Biodiversity monitoring for discovering newcomer invasive species, measures for environmental recovery of these ecosystems and strict controls to avoid increasing of harvesting pressures are also a necessity to improve the management of these relevant ecosystems.     

Basin‐scale distribution and haplotype partitioning in different genetic lineages of the Neotropical migratory fish Salminus brasiliensis

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Identification of gadoid species in fish meat by polymerase chain reaction (PCR) on genomic DNA

Identification of fish species is significant due to the increasing interest of consumers in the meat of sea fish. Methods focusing on fish species identification help to reveal fraudulent substitution among economically important gadoid species in commercial seafood products. The objective of this work was to develop a conventional PCR method for the differentiation of the following gadoid fish species in fish products: Alaska pollack ( Theragra chalcogramma), blue whiting ( Micromesistius poutassou), hake spp. ( Merluccius spp.), Atlantic cod ( Gadus morhua), saithe ( Pollachius virens), and whiting ( Merlangius merlangus). The species-specific primer pairs for gadoid species determination were based on the partial pantophysin I ( PanI) genomic sequence. Sequence identification was confirmed by cloning and sequencing of the PCR products obtained from the species considered. For the simultaneous detection of Alaska pollack, blue whiting, and hake spp., a quadruplex PCR system was constructed. Other gadoid species were detected in separate PCR reactions. After optimization of the reactions, the developed PCR systems were used for the analysis of codfish samples obtained from the Czech market and the customs' laboratories. This method represents an alternative approach in the use of genomic DNA for the identification of fish species. This method is rapid, simple, and reliable without the need for further confirmative methods. Furthermore, the identification of a mixture of more than one species is possible. The PCR system has been optimized for routine diagnostic purposes.     

Predicting ash dieback severity and environmental suitability for the disease in forest stands

Ash dieback, caused by the ascomycete fungus Hymenoscyphus fraxineus, has been rapidly expanding across Europe during the last two decades, posing a considerable threat to native ash populations. In this study, we applied regression-based models trained by field data, in conjunction with geographic information systems, to produce spatial predictions of ash dieback severity and environmental suitability for the disease in Czech forests. A model of actual ash dieback severity relates disease extent to silvicultural and environmental characteristics of forest stands and their neighbourhood, while a model of environmental suitability for the disease quantifies the relative susceptibility of sites to the disease, independent of the current silvicultural characteristics. The final predictive maps suggested that fertile lowlands and humid areas bordering Poland and Slovakia were the most endangered regions. Areas at the lowest risk of damage were concentrated in dry areas and in highland and mountain areas in the western part of the country, usually with poor soils on acid bedrock. Predictions of actual disease severity are an effective tool for guiding the current management of infested stands whereas predicting environmental suitability is useful for making long-term strategic decisions, e.g. identifying areas where future ash regeneration and cultivation may be unsuccessful.     

Mediterranean diet in relation to body mass index and waist-to-hip ratio

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Combined application of antagonist Bacillus amyloliquefaciens and essential oils for the control of peach postharvest diseases

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When international impulses hit home: The role of domestic policy subsystem configurations in explaining different types of sustainability strategies

This paper deals with the role of new ideas and actors regarding national level strategy processes and their respective output. Accordingly, the theoretical framework addresses the relation between a policy subsystem's receptiveness to new ideas and actors and the actual presence of new actors and/or new ideas induced by international impulses (independent variables), and the likely influence of the configuration of these factors on strategy processes and their output. Depending on actual subsystem configurations, we deduce four ideal types of strategy processes and outputs (dependent variables): change-oriented, output-oriented, process-oriented and rhetorical strategies.Empirically, we have conducted a comparative analysis of the effects of one legally binding and two non-legally binding international agreements in terms of the changes induced by means of national strategy processes: the Austrian Biodiversity Strategy, the Austrian Forest Dialogue, and the Austrian Strategy for Sustainable Development. These strategies all have their roots in the UNCED Conference in 1992. The respective discourses and agreements introduced new idea sets to national policy processes also promoting participatory, long-term, cross-sectoral and multi-level strategy processes.The empirical analysis confirms effects of the international impulses in terms of introducing new ideas and actors. However, our case studies also point out that the actual effects of similar international impulses for change seem to be systematically mediated by the pre-existing domestic policy subsystem configurations, resulting in substantially different strategy processes and outputs, ranging from quite substantive changes to a mere rhetorical fulfillment of international agreements.     

Revisiting the politics of expertise in light of the Kyoto negotiations on land use change and forestry

This paper examines the close links between knowledge-making authority and decision making authority in the multilateral negotiations on terrestrial sinks of greenhouse gases. Drawing upon social constructivist science studies and public sphere theories in international relations, the paper traces the communicative contexts in which state actors have struggled to bring meaning to the sink concept and hereby translated the production and validation of knowledge claims into political authority. In particular focus are instances of “epistemic chaos” when the lack of consensual knowledge and shared normative commitments has forced states to publicly interpret and justify what counts as credible carbon cycle expertise and good terrestrial carbon management. The empirical tracing of such justificatory arguments begins at the third conference of the parties (COP3) to the United Nations Framework Convention on Climate Change in Kyoto in 1997, and ends at COP 10 in Buenos Aires in 2004. Although scientific expertise emerges a central avenue for political bargaining in this negotiation process, the paper does not interpret expert politics as a mere reflection of material power and dominant state interests. Rather, when approaching authoritative knowledge as a product of social relations, the course and outcome of global climate governance appear more inclusive and open-ended.