Potential impact of processed Harmonia axyridis on the taste of ‘Chasselas’ and ‘Pinot noir’ wines

Research Note

Influence of processed Halyomorpha halys bugs on the aroma and taste of 'Chardonnay' and 'Merlot' musts and wines

Native to East Asia, the invasive brown marmorated stink bug (Halyomorpha halys) was accidentally introduced into Switzerland around 2004 and is now spreading all over Europe. This pentatomid is highly polyphagous and attacks vegetables, field and tree crops as well as soft fruits. Moreover, all development stages of H. halys are found in vineyards, suggesting that grapevine is also a host plant for this insect. Nonetheless, its actual effects on European wine production is unclear. As such, we studied the impact of processed H. halys on the aroma and taste of grape musts and wines. We artificially contaminated 'Chardonnay' and 'Merlot' grapes with up to ten H. halys nymphs and adults per kg grapes directly before the vintage was crushed. In the freshly pressed must, the addition of 1 living bug/kg grapes did not affect the olfactory sensation of the 'Chardonnay' juice. However, the aroma and taste of 'Chardonnay' and 'Merlot' musts contaminated with 3 to 10 H. halys individuals/kg grapes could be distinguished from the uncontaminated control juices and were perceived as vegetal and woody. Yet after bottling, the different wines with 0 to 10 H. halys individuals/kg grapes could no longer be differentiated from each other in 2-out-of-5 discrimination tests. Amongst 17 rated organoleptic descriptors to characterise the sensory profile of the four 'Chardonnay' wines, only two showed significant differences; the colour intensity increased and wines’ finesse decreased with the number of added bugs. For the three 'Merlot' wines, none of the 21 organoleptic descriptors of the sensory profiles differed significantly. In addition, winegrowers did not dislike H. halys contaminated 'Chardonnay' and 'Merlot' wines compared to their uncontaminated controls one year after bottling. It therefore seems that the molecules responsible for the off-flavours in contaminated musts volatilise to a large part during the fermentation process. Our results consequently indicate that a contamination of the vintage with H. halys has the potential to alter the quality of grape musts and potentially grape juices but that there is little risk for influencing the taste of processed wines. Nonetheless, we recommend monitoring the development of H. halys in vineyards in order to anticipate quantitative and qualitative problems at harvest

Efficacy of kaolin treatments against Drosophila suzukii and their impact on the composition and taste of processed wines

Drosophila suzukii is a very polyphagous species that can also tack and develop in a great variety of grape cultivars. In Switzerland, the control of D. suzukii mainly relies on prophylactic measures and kaolin, a white inert aluminosilicate mineral who's particles stick to the leaf surface and form a physical barrier that help to reduce ovipositions by the pest. Here we present a synthesis of our recent insights on the efficacy of kaolin against D. suzukii as well as on the chemical and sensory properties of the wines vinified from kaolin treated grapes. In autumn 2016, kaolin (Surround WP®) was applied in 23 field trials on various cultivars located in various winegrowing regions of Switzerland. Overall, kaolin achieved an average efficiency of 54 % and no significant differences could be observed between kaolin applications at 1 % and 2 % with 56.8 % and 57.1 % efficacy, respectively. At the higher concentration, the preventive and curative strategy were also nearly as effective with efficacies at 67.4 % and 50.3 %, respectively. In addition, a field experiment was set up on the red grape cultivar 'Mara' in 2015. This experiment revealed that three applications of kaolin at 1 % or 2 % did neither affect fermentation nor the usual chemical properties of kaolin treated wines compared to the untreated control. However, aluminum concentration within wines increased with the applied dosage of kaolin but the measured aluminum levels were 38-times lower than the maximal German threshold of 8 mg·L-1. Moreover, tasters were also not able to distinguish the aroma and the taste of wines processed from kaolin treated grapes from the untreated control. We therefore conclude that kaolin applications are effective against D. suzukii and do not cause any major risks to the environment, to wine quality and to human health

Impact of processed earwigs and their faeces on the aroma and taste of 'Chasselas' and 'Pinot Noir' wines

The abundance of the European earwig Forficula auricularia L. (Dermaptera, Forficulidae) in European vineyards increased considerably over the last few years. Although earwigs are omnivorous predators that prey on viticultural pests such as grape moths, they are also known to erode berries and to transfer fungal spores. Moreover, they are suspected to affect the human perception of wines both directly by their processing with the grapes and indirectly by the contamination of grape clusters with their faeces. In this study we artificially contaminated grapes with F. auricularia adults and/or their faeces and determined the impact on aroma and taste of white 'Chasselas' and red 'Pinot noir' wines. Whereas the addition of five living adults/kg grapes affected the olfactory sensation of 'Chasselas' wines only marginally, 0.6 gram of earwig faeces/kg grapes had a strong effect on colour, aroma and the general appreciation of 'Chasselas' wines. Faeces-contaminated wines were less fruity and less floral, the aroma was described as faecal and they were judged to be of lower quality. The contamination of 'Pinot noir' grapes with four different densities of living earwig adults (e.g. 0, 5, 10 and 20 individuals/kg grapes) showed that only wines contaminated with more than 10 earwigs/kg grapes smelled and tasted significantly different than the uncontaminated control wine. Earwig-contaminated 'Pinot noir' wines were judged to be of lower quality. The descriptors “animal”, “reductive”, “vegetal”, “acidic”, “bitter” and “tannic” characterised their sensory perception. In conclusion, our results show that there is a real risk of wine contamination by F. auricularia. In particular, earwig faeces and earwig adults at densities above a threshold of 5 to 10 individuals/kg grapes have the potential to reduce the quality of wines. The evolution of earwig populations in vineyards should therefore be monitored carefully in order to anticipate problems during vinification.

In-Depth Global Analysis of Transcript Abundance Levels in Porcine Alveolar Macrophages Following Infection with Porcine Reproductive and Respiratory Syndrome Virus

Porcine reproductive and respiratory syndrome virus (PRRSV) is a major pathogen of swine worldwide and causes considerable economic loss. Identifying specific cell signaling or activation pathways that associate with variation in PRRSV replication and macrophage function may lead to identification of novel gene targets for the control of PRRSV infection. Serial Analysis of Gene Expression (SAGE) was used to create and survey the transcriptome of in vitro mock-infected and PRRSV strain VR-2332-infected porcine alveolar macrophages (PAM) at 0, 6, 12, 16, and 24 hours after infection. The transcriptome data indicated changes in transcript abundance occurring in PRRSV-infected PAMs over time after infection with more than 590 unique tags with significantly altered transcript abundance levels identified (P < .01). Strikingly, innate immune genes (whose transcript abundances are typically altered in response to other pathogens or insults including IL-8, CCL4, and IL-1β) showed no or very little change at any time point following infection

Including community composition in biodiversity–productivity models

Studies on biodiversity and ecosystem functioning (BEF) have elicited debate over the interpretation of the positive relationship between species richness and plant productivity. Manipulating richness cannot be achieved without affecting composition; it is thus essential to consider the latter in statistical models.We firstly review existing approaches that use species richness as an explanatory variable and propose modifications to improve their performance. We use an original data set to illustrate the analyses. The classical method where composition is coded as a factor with a level for each different species mixture can be improved by defining the levels using clustering. Methods based on ordinations reduce the dimensionality of plant composition and use the new coordinates as fixed effects; they provide a much better fit to our observations.Secondly, we develop a new method where composition is included as a similarity matrix affecting the residual variance–covariance. Similarity in composition between plots is treated in the same way as shared evolutionary history between species in phylogenetic regression. We find that it outperforms the other models.We discuss the different approaches and suggest that our method is particularly suited for observational studies or for manipulative studies where plant diversity is not kept constant by weeding. By treating species composition in an intuitive and sensible way, it offers a valuable and powerful complement to existing models

Measurement of the ATLAS solenoid magnetic field

ATLAS is a general purpose detector designed to explore a wide range of physics at the Large Hadron Collider. At the centre of ATLAS is a tracking detector in a 2 T solenoidal magnetic field. This paper describes the machine built to map the field, the data analysis methods, the final results, and their estimated uncertainties. The remotely controlled mapping machine used pneumatic motors with feedback from optical encoders to scan an array of Hall probes over the field volume and log data at more than 20 000 points in a few hours. The data were analysed, making full use of the physical constraints on the field and of our knowledge of the solenoid coil geometry. After a series of small corrections derived from the data itself, the resulting maps were fitted with a function obeying Maxwell's equations. The fit residuals had an r.m.s. less than 0.5 mT and the systematic error on the measurement of track sagitta due to the field uncertainty was estimated to be in the range 0.02 % to 0.12 % depending on the track rapidity

High-impact animal health research conducted at the USDA’s National Animal Disease Center

Commissioned by President Dwight Eisenhower in 1958 and opened with a dedication ceremony in December 1961, the USDA, Agricultural Research Service (ARS), National Animal Disease Center (NADC) celebrated its 50-year anniversary in November 2011. Over these 50 years, the NADC established itself among the world’s premier animal health research centers. Its historic mission has been to conduct basic and applied research on selected endemic diseases of economic importance to the U.S. livestock and poultry industries. Research from NADC has impacted control or management efforts on nearly every major animal disease in the United States since 1961. For example, diagnostic tests and vaccines developed by NADC scientists to detect and prevent hog cholera were integral in the ultimate eradication of this costly swine disease from the U.S. Most major veterinary vaccines for critical diseases such as brucellosis and leptospirosis in cattle, porcine respiratory and reproductive syndrome (PRRS), porcine parvovirus and influenza in swine had their research origins or were developed and tested at the NADC. Additional discoveries made by NADC scientists have also resulted in the development of a nutritional approach and feed additives to prevent milk fever in transition dairy cattle. More recently, NADC’s archive of historic swine influenza viruses combined with an established critical mass of influenza research expertise enabled NADC researchers to lead an effective national research response to the pandemic associated with the novel 2009 H1N1 influenza virus. This review commemorates some of the key animal health contributions in NADC’s first 50 years, recaps the newly completed modernization of the center into new facilities, and offers highlights of the ongoing research that will define NADC’s mission going forward

The relative contributions of species richness and species composition to ecosystem functioning

How species diversity influences ecosystem functioning has been the subject of many experiments and remains a key question for ecology and conservation biology. However, the fact that diversity cannot be manipulated without affecting species composition makes this quest methodologically challenging. Here, we evaluate the relative importance of diversity and of composition on biomass production, by using partial Mantel tests for one variable while controlling for the other. We analyse two datasets, from the Jena (2002–2008) and the Grandcour (2008–2009) Experiments. In both experiments, plots were sown with different numbers of species to unravel mechanisms underlying the relationship between biodiversity and ecosystem functioning (BEF). Contrary to Jena, plots were neither mowed nor weeded in Grandcour, allowing external species to establish. Based on the diversity–ecosystem functioning and competition theories, we tested two predictions: 1) the contribution of composition should increase with time; 2) the contribution of composition should be more important in non-weeded than in controlled systems. We found support for the second hypothesis, but not for the first. On the contrary, the contribution of species richness became markedly more important few years after the start of the Jena Experiment. This result can be interpreted as suggesting that species complementarity, rather than intraspecific competition, is the driving force in this system. Finally, we explored to what extent the estimated relative importance of both factors varied when measured on different spatial scales of the experiment (in this case, increasing the number of plots included in the analyses). We found a strong effect of scale, suggesting that comparisons between studies, and more generally the extrapolation of results from experiments to natural situations, should be made with caution

Measurement of the solenoid magnetic field

We describe the machine used to map the solenoid field and the data sets that were collected. The bulk of the note describes the analysis of this data. A series of small corrections are made; some taken from surveys and some derived from the data itself. Two fitting methods are defined and applied to all data sets. The final result is that the field map at normal operating current can be fitted to a function that obeys Maxwell with an r.m.s. residual of less than 5 Gauss. Systematic errors on the measurement of track sagitta due to the field uncertainty are estimated to be in the range 2.3E-4 to 12E-4, depending on the track rapidity. Finally, the representation of the map in Athena is briefly described