Multivariate analysis of phenotypic diversity of Coffea arabica

Summary Eighteen different morphological and agronomical traits observed in a field collection of 148 accessions of Coffea arabica were analyzed using multivariate analysis. For the first time, a clear structure is observed within this species with the identification of two main groups. Accessions of group 1 have a more erect branching habit, narrower leaves and are on average more resistant to coffee leaf rust and coffee berry disease than accessions of group 2. Group 1 mostly contains Ethiopian accessions collected west of the Great Rift Valley, whereas group 2 mostly contain commonly cultivated varieties throughout the world and Ethiopian accessions collected east of the Great Rift Valley in Ethiopia. This phenotypic structure together with historical evidence suggest that group 1 has not been involved in the domestication of C. arabica. The present results confirm that sub-spontaneous genotypes west of the Rift Valley are highly valuable for enriching the genetic basis of cultivated C. arabica germplasm. The potential value of this material in breeding of C. arabica is discussed.     

The Influence of Sediment Sources and Hydrologic Events on the Nutrient and Metal Content of Fine-Grained Sediments (Attert River Basin, Luxembourg)

Nutrient (C, N and P) and metal (Cr, Cu, Ni, Pb and Zn) content and dynamics of suspended and channel bed sediments were analysed within the rural Attert River basin (Luxembourg). This basin is representative of the main physiographic characteristics of the country, where there is currently little information available on the composition and dynamics of fluvial sediment. Stream bed fine-grained sediment samples (n?=?139) collected during low flow conditions and time-integrated suspended sediment samples (n?=?183) collected during storm runoff events (October 2005 to April 2008) in seven nested basins ranging from 0.45 to 247?km² were analysed. Nutrient and metal spatial patterns, temporal trends and the relationship between their content and storm runoff characteristics (e.g. maximum discharge and sediment concentration) were assessed. Results showed a high spatial and temporal variability, mainly associated with basin characteristics and local inputs. Higher values of total C were measured in the highly forested basins located in the northern part of the Attert River basin, whereas the highest values of total P were mainly associated with material coming from grassland and with the inflow of wastewater treatment plants (i.e. higher values of total P were measured in the southern part of the basin). The abundance of metals, not only in suspended but also in channel bed sediments, was generally as follows: Zn > Cr > Ni > Pb > Cu. Both nutrient and metal concentrations were at a maximum at the beginning of the wet season, after having been accumulated during the summer. These values tended to decrease during autumn and winter due to sediment mobilisation, and a higher flow capacity to transport coarser particle fractions from the sources. In general, concentrations of nutrients and metals on suspended sediment were negatively correlated with antecedent precipitation, total precipitation, total specific discharge and maximum discharge, which has been previously associated to a ??dilution?? effect during storm runoff events. Results show that both sediment sources and hydrologic events play an important role on the spatial and temporal variability of sediment-associated nutrient and metal contents.     

Trace and major element contents,microbial communities,and enzymatic activities of urban soils of Marrakech city along an anthropization gradient

Journal of Soils and Sediments - Due to their close proximity with the population, urban soils are extensively affected by human activities that release considerable technogenic inputs resulting in...     

Pyranose Oxidase from Trametes multicolor Impacts Dough and Bread Microstructure

Pyranose oxidase (P₂O) improves wheat flour dough stability and bread quality. We related its effect on dough spread behavior to that on dough and bread crumb structure. Increasing P₂O addition levels gradually reduced dough flow. High P₂O addition levels further increased dough strength, significantly increased dough cell wall thickness, and decreased bread loaf volume. Taken together, affecting dough spread behavior impacts dough and bread (crumb) structure, and dough structure largely determines bread crumb structure.     

Structural diversity of sodium

Sodium exhibits a pronounced minimum of the melting temperature at approximately 118 gigapascals and 300 kelvin. Using single-crystal high-pressure diffraction techniques, we found that the minimum of the sodium melting curve is associated with a concentration of seven different crystalline phases. Slight changes in pressure and/or temperature induce transitions between numerous structural modifications, several of which are highly complex. The complexity of the phase behavior above 100 gigapascals suggests extraordinary liquid and solid states of sodium at extreme conditions and has implications for other seemingly simple metals.     

Incorporating uncertainty into analyses of red-crested pochard habitat selection

Studies describing habitat use in animal species need to take into account detectability of individuals in order to reach more robust conclusions. However, the importance of detectability in habitat selection analyses of rare and cryptic species has received little investigation, although robust methods for estimating detectability have been made recently available. Understanding habitat requirements should be an important management tool for the conservation of the red-crested pochard (Netta rufina), a rare duck species in France and Europe. Three different lake samples (82 lakes in total) were conjointly used in 2000 and 2001 to assess the species habitat requirements, using its presence, density and hatching dates as response variables. Risk of false absence was estimated using the double-observer approach at less than 0.001. A robust-design approach produced estimates of individual brood detectability (0.545, SE = 0.053). Observed red-crested pochard densities were adjusted to time dependent detectabilities, and modelled as a function of habitat variables. Habitat fragmentation and low permanent water levels negatively affected brood densities. Interestingly, these variables were not retained when modelling the unadjusted densities. This analysis showed that investigating temporal variation in brood detectability was a crucial prerequisite in the study of this rare species’ habitat requirements. More generally, it strongly suggests that integrating detection probability and its variations in habitat use analyses of cryptic species of conservation concern may be an essential methodological step to reach more valid conclusions on habitat management.     

Photosynthesis of the grapevine (Vitis vinifera) inflorescence

To further characterize carbohydrate physiology in grapevine flowers, we examined inflorescence autotrophy in the 'Gewurztraminer' and 'Pinot noir' cultivars, which differ in sensitivity to flower abscission. In both cultivars, positive net photosynthesis occurred in inflorescences. The rate of photosynthesis gradually decreased throughout flower development and there was no net carbon assimilation at fruit set. The rate of photosynthesis was positively correlated with chlorophyll concentration but not to stomatal conductance. Throughout flower development, the internal CO2 concentration increased in inflorescence tissues, suggesting that assimilates are also formed through refixation of respiratory CO2 by the phosphoenolpyruvate carboxylase (PEPC) pathway. Significant differences between the two cultivars were recorded during meiosis, when photosynthesis was higher in 'Gewurztraminer'. We conclude that the inflorescence of grapevine contributes to its own carbon nutrition by photosynthesizing throughout flower development. Moreover, the differential patterns of photosynthesis in the inflorescences of 'Gewurztraminer' and 'Pinot noir' might account for their differing fertilization rates and sensitivity to flower abscission.     

The status of marine biodiversity in the Eastern Central Atlantic (West and Central Africa)

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Development of a sensitive ELISA using three monoclonal antibodies against lipopolysaccharides to detect <Emphasis Type="Italic">Xanthomonas campestris</Emphasis> pv. <Emphasis Type="Italic">vesicatoria</Emphasis>, the causal agent of bacterial spot of tomato and pepper

Bacterial spot, caused by Xanthomonas campestris pv. vesicatoria (Doidge 1920) Dye 1978 (Xcv), is responsible for severe production losses in tomato and pepper. Three specific monoclonal antibodies (MABs), 7AH10, 5HB3, and 4AD2, which are reactive to lipopolysaccharides of the bacteria, were tested in three kinds of enzyme-linked immunosorbent assays (ELISAs). The most sensitive ELISA was a competitive one able to detect populations of Xcv as low as 10³–10⁴cfu/ml. Bacterial growth in artificially inoculated tomato and pepper plants could be successfully monitored, and assays on field-collected samples reconfirmed the diagnostic utility of the MABs. Studies on the accessibility of the MABs to their lipopolysaccharide epitopes confirmed that sample preparation can be improved to further increase the sensitivity of the assay. Immunoblotting of differential extracts of the bacterial cells and immunoelectron microscopy demonstrated that the epitopes were present throughout the cell wall and involved in complexes that can be loosened through the action of proteinase K or lysozyme.     

167 individuals versus millions of hooks: bycatch mitigation in longline fisheries underlies conservation of Amsterdam albatrosses

1. Industrial fisheries represent one of the most serious threats worldwide to seabird conservation. Death of birds in fishing operations (i.e. bycatch) has especially adverse effects on populations of albatrosses, which have extremely low fecundity. 2. The single population worldwide of Amsterdam albatross (Diomedea amsterdamensis) comprises only 167 individuals and risks considerable decline over the mid‐term from additional mortality levels potentially induced by fisheries. The priority actions listed in the current conservation plan for this species included characterizing the longline fisheries operating within its range, dynamically analysing the overlap between albatrosses and these fisheries, and providing fisheries management authorities with potential impact estimates of longline fisheries on the Amsterdam albatross. 3. During all life‐cycle stages and year quarters the birds overlapped extensively with fishing effort in the southern Indian and Atlantic oceans. Fishing effort, and consequently overlap score (calculated as the product of fishing effort and time spent by the birds in a spatial unit) was highest in July–September (45% of the hooks annually deployed). Just three fleets (Taiwanese, Japanese and Spanish) contributed to >98% of the overlap scores for each stage (72% from the Taiwanese fleet alone, on average). Daily overlap scores were higher for the non‐breeding versus the breeding stages (3‐fold factor on average). 4. Based on previous bycatch rates for other albatross species, this study estimated that longline fisheries currently have the potential to remove ~2–16 individuals (i.e. ~5%) each year from the total Amsterdam albatross population, depending on whether bycatch mitigation measures were or were not systematically employed during the fishing operations. 5. Recent bycatch mitigation measures may be instrumental in the conservation of the Amsterdam albatross. This study suggests three further key recommendations: (1) to focus conservation efforts on the austral winter; (2) to require all operating vessels to report ring recoveries; and (3) to allocate special regulation of fishing operations in the areas of peak bycatch risk for the Amsterdam albatrosses. Copyright © 2015 John Wiley & Sons, Ltd.