Narrow versus broad: sexual dimorphism in the wing form of western European species of the subgenus Avaritia (Culicoides,Ceratopogonidae)

While wing form is known to differ between males and females of the genus Culicoides, detailed studies of sexual dimorphism are lacking. In this study, we analyze sex-specific differences in the wing form of 5 species of the subgenus Avaritia, using geometric morphometrics and comparative phylogenetic methods. Our results confirm the existence of marked sexual dimorphism in the wing form of the studied species and reveal for the first time that while there is a shared general pattern of sexual shape dimorphism within the subgenus, sexual size dimorphism, and particular features of sexual shape dimorphism differ among species. Sexual shape dimorphism was found to be poorly associated to size and the evolutionary history of the species. The tight association of sexual shape dimorphism with aspect ratio suggests that the shape of the wing is optimized for the type of flight of each sex, that is, dispersal flight in females versus aerobatic flight in males. Moreover, the fact that interspecific shape differences are greater and more strongly associated to aspect ratio in males than in females might be indicating that in males the selective pressures affecting flight performance characteristics are more heterogeneous and/or stronger than in females among the studied species.     

Pathogenesis and transmissibility of highly (H7N1) and low (H7N9) pathogenic avian influenza virus infection in red-legged partridge (Alectoris rufa)

ABSTRACT: An experimental infection with highly pathogenic avian influenza virus (HPAIV) and low pathogenic avian influenza virus (LPAIV) was carried out in red-legged partridges (Alectoris rufa) in order to study clinical signs, gross and microscopic lesions, and viral distribution in tissues and viral shedding. Birds were infected with a HPAIV subtype H7N1 (A/Chicken/Italy/5093/1999) and a LPAIV subtype H7N9 (A/Anas crecca/Spain/1460/2008). Uninoculated birds were included as contacts in both groups. In HPAIV infected birds, the first clinical signs were observed at 3 dpi, and mortality started at 4 dpi, reaching 100% at 8 dpi. The presence of viral antigen in tissues and viral shedding were confirmed by immunohistochemistry and quantitative real time RT-PCR (qRRT-PCR), respectively, in all birds infected with HPAIV. However, neither clinical signs nor histopathological findings were observed in LPAIV infected partridges. In addition, only short-term viral shedding together with seroconversion was detected in some LPAIV inoculated animals. The present study demonstrates that the red-legged partridge is highly susceptible to the H7N1 HPAIV strain, causing severe disease, mortality and abundant viral shedding and thus contributing to the spread of a potential local outbreak of this virus. In contrast, our results concerning H7N9 LPAIV suggest that the red-legged partridge is not a reservoir species for this virus.     

The risks of success in quality vegetable markets: Possible genetic erosion in Marmande tomatoes (Solanum lycopersicum L.) and consumer dissatisfaction

Following consumer complaints about the quality of modern varieties of tomato, landraces have strengthened their quality markets. In Spain, two tomato landraces, ‘Montserrat’ and ‘Pera Girona’, are grown in contiguous areas and have different market niches. We used amplified fragment length polymorphism (AFLP) to characterize 13 accessions of Montserrat, 14 accessions of Pera Girona, and 4 control varieties. We found a narrow genetic base for ‘Montserrat’ and ‘Pera Girona’ (8.5% of polymorphic loci) and no differences between the landraces. We studied agronomical and sensory traits to determine why the two landraces continue to have separate market niches. We found high variability among accessions within each landrace and overlapping among accessions of both landraces for all traits except fruit morphology. Consumers probably came to associate the organoleptic quality of these landraces with their external traits, but due to spontaneous crossings and introgressions these relations have been lost. Selection within landraces will be necessary to reestablish the link between morphology and sensory value and to consolidate these quality markets.     

Nitrogen Lost during MSW Composting at Two Facilities in Spain

? The objective of this study was to evaluate and compare nitrogen losses during the composting process developed at two facilities. Both are in Catalonia, which is located in northeast Spain. The research evaluated the effects of process, feedstock content, differences in compost maturity and other factors to explain differences in nitrogen levels. Separation methods and leachate problems were also compared.     

Differences in swimming performance and energetic costs between an endangered native toothcarp (Aphanius iberus) and an invasive mosquitofish (Gambusia holbrooki)

Swimming performance is a key feature that mediates fitness and survival in many fish species. Using a swim tunnel respirometer, we compared prolonged swimming performance and energy use for two competing species: an endangered, endemic toothcarp (Aphanius iberus) and a worldwide invasive mosquitofish (Gambusia holbrooki). Critical (U_crit) and optimal swimming speeds, standard and maximal metabolic rates, absolute aerobic scope, as well as the minimum cost of transport were estimated and compared between species and sexes. Body streamlining and caudal peduncle depth were also measured to explain the differences in swimming performance and efficiency. Both sexes of A. iberus presented similar swimming capacity and metabolic traits, whereas males of G. holbrooki showed higher critical swimming speeds, maximal metabolic rate and absolute aerobic scope than females. We also found marked differences between species in most of the response variables examined. Aphanius iberus showed lower swimming capacity (U_crit mean <10 cm s⁻¹), higher maximal metabolic rate and absolute aerobic scope than the invasive species. By contrast, G holbrooki swam faster and had lower cost of transport at a given fish mass and speed, thereby leading to a higher swimming efficiency. The observed differences in swimming efficiency were closely related to differences in morphological characteristics and therefore to drag pressures and propulsion. Our results add a mechanistic basis to the ecological understanding of these two species and suggest that although both are poor swimmers compared to many other similarly sized species, the native species likely has more restricted water flow tolerance and dispersal capacities.     

Precursor uptake assays and metabolic analyses in isolated tomato fruit chromoplasts

Background  

Carotenoids are the most widespread group of pigments found in nature. In addition to their role in the physiology of the plant, carotenoids also have nutritional relevance as their incorporation in the human diet provides health benefits. In non-photosynthetic tissues, carotenoids are synthesized and stored in specialized plastids called chromoplasts. At present very little is known about the origin of the metabolic precursors and cofactors required to sustain the high rate of carotenoid biosynthesis in these plastids. Recent proteomic data have revealed a number of biochemical and metabolic processes potentially operating in fruit chromoplasts. However, considering that chloroplast to chromoplast differentiation is a very rapid process during fruit ripening, there is the possibility that some of the proteins identified in the proteomic analysis could represent remnants no longer having a functional role in chromoplasts. Therefore, experimental validation is necessary to prove whether these predicted processes are actually operative in chromoplasts.     

Evaluation of the Removal of Pollutants from Petrochemical Wastewater Using A Membrane Bioreactor Treatment Plant

Water, Air, & Soil Pollution - A submerged membrane bioreactor (MBR) was used to treat two types of petrochemical wastewater: olefin process wastewater and total petrochemical wastewater....