scholarly journals Effects of Variety and Grape Berry Condition of Vitis vinifera on Preference Behavior and Performance of Drosophila suzukii

Insects ◽  
2019 ◽  
Vol 10 (12) ◽  
pp. 432 ◽  
Author(s):  
Lisa Weißinger ◽  
Niklas Samuel ◽  
Michael Breuer ◽  
Caroline Müller
Keyword(s):  
Management Strategies ◽  
Grape Berry ◽  
Pinot Noir ◽  
Drosophila Suzukii ◽  
Offspring Performance ◽  
Economic Threat ◽  
Berry Crops ◽  
And Performance ◽  
Grape Varieties ◽  
The Impact

Drosophila suzukii is an invasive fruit pest and represents a potential economic threat to viticulture. After first observations of D. suzukii in Europe in 2008, research mainly focused on the evaluation of the host range and infestation risk for fruit and berry crops. However, the risk assessment of D. suzukii in viticulture has only recently started. Understanding the factors influencing preferences of D. suzukii for host species and varieties as well as offspring performance is essential to improve management strategies. We investigated the field infestation of different grape varieties across Baden-Wuerttemberg, southwestern Germany, between 2015 and 2018. Moreover, we performed dual-choice assays in the laboratory to investigate whether adults show preferences for certain varieties and whether offspring performance differs between varieties. Furthermore, we studied the impact of grape damage on choice behavior. Field monitoring revealed that D. suzukii show preferences for red varieties, whereas almost no oviposition occurred in white varieties. The results of dual-choice assays confirmed that D. suzukii preference and performance are influenced by grape variety and that flies preferred damaged over intact “Pinot Noir”, “Pinot Blanc”, and “Müller-Thurgau” berries. Overall, these findings may have important implications for winegrowers regarding cultivated varieties, grape health, and insecticide reduction.

HRSG Fleet Integrity Management: Lessons Learned From the Field

2020 ◽  
Author(s):  
Andreas Fabricius ◽  
James Malloy ◽  
Mark Taylor ◽  
Peter Jackson ◽  
David Moelling
Keyword(s):  
Asset Management ◽  
Corporate Strategy ◽  
Management Strategies ◽  
Cost Effective ◽  
Operating Mode ◽  
Field Work ◽  
Lessons Learned ◽  
Management Actions ◽  
And Performance ◽  
The Impact

Abstract This paper presents key lessons learned from hundreds of field missions for assessing the condition of HRSGs at sites around the world. These involved field inspections, root cause of failure analyses and performance assessments on HRSGs of nearly every design, fuel type and operating mode. Statistics on degradation and failure risk areas are presented. Analysis techniques used in both preparing for field work and in assessing field examination results are also discussed. Trends in the evolution of the principal damage mechanisms over the years are examined, and predictions of future problem areas are considered with a view to guiding asset management actions. The impact on HRSG integrity of changes in unit designs, such as the move to flexible operation in response to the increasing contribution from renewables, is also assessed, and likely future trends are outlined. The use of qualitative and quantitative risk-based methods is also discussed and compared to the use of condition-based inspection methods as a basis for a fleet wide management strategy. A case study including a large IPP with several generating assets in its portfolio is presented and the most cost-effective method with respect to current corporate strategy is discussed. Recommendations for fleet management strategies are made.

scholarly journals Fisheries management under climate and environmental uncertainty: control rules and performance simulation

2013 ◽  
Vol 71 (8) ◽  
pp. 2208-2220 ◽  
Author(s):  
André E. Punt ◽  
Teresa A'mar ◽  
Nicholas A. Bond ◽  
Douglas S. Butterworth ◽  
Carryn L. de Moor ◽  
...  
Keyword(s):  
Fishery Management ◽  
Climate Models ◽  
Global Climate ◽  
Management Strategies ◽  
Environmental Variation ◽  
Global Climate Models ◽  
Reference Points ◽  
Environmental Data ◽  
And Performance ◽  
The Impact

Abstract The ability of management strategies to achieve the fishery management goals are impacted by environmental variation and, therefore, also by global climate change. Management strategies can be modified to use environmental data using the “dynamic B0” concept, and changing the set of years used to define biomass reference points. Two approaches have been developed to apply management strategy evaluation to evaluate the impact of environmental variation on the performance of management strategies. The “mechanistic approach” estimates the relationship between the environment and elements of the population dynamics of the fished species and makes predictions for population trends using the outputs from global climate models. In contrast, the “empirical approach” examines possible broad scenarios without explicitly identifying mechanisms. Many reviewed studies have found that modifying management strategies to include environmental factors does not improve the ability to achieve management goals much, if at all, and only if the manner in which these factors drive the system is well known. As such, until the skill of stock projection models improves, it seems more appropriate to consider the implications of plausible broad forecasts related to how biological parameters may change in the future as a way to assess the robustness of management strategies, rather than attempting specific predictions per se.

scholarly journals Influence of the Rearing Host on Biological Parameters of Trichopria drosophilae, a Potential Biological Control Agent of Drosophila suzukii

Insects ◽  
2019 ◽  
Vol 10 (6) ◽  
pp. 183 ◽  
Author(s):  
Svetlana Boycheva Woltering ◽  
Jörg Romeis ◽  
Jana Collatz
Keyword(s):  
Biological Control ◽  
Biological Control Agent ◽  
Control Agent ◽  
Invasive Pest ◽  
Drosophila Suzukii ◽  
Female Ratio ◽  
Host Switch ◽  
And Performance ◽  
Different Strains ◽  
The Impact

Trichopria drosophilae is a pupal parasitoid that can develop in a large number of drosophilid host species including the invasive pest Drosophila suzukii, and is considered a biological control agent. We investigated the influence of the rearing host on the preference and performance of the parasitoid, using two different strains of T. drosophilae, reared on D. melanogaster or D. suzukii for approximately 30 generations. Host switching was employed to assess the impact of host adaptation on T. drosophilae performance. In a no-choice experimental setup, T. drosophilae produced more and larger offspring on the D. suzukii host. When given a choice, T. drosophilae showed a preference towards D. suzukii, and an increased female ratio on this host compared to D. melanogaster and D. immigrans. The preference was independent from the rearing host and was confirmed in behavioral assays. However, the preference towards D. suzukii increased further after a host switch from D. melanogaster to D. suzukii in just one generation. Our data indicate that rearing T. drosophilae for several years on D. melanogaster does not compromise its performance on D. suzukii in the laboratory. However, producing a final generation on D. suzukii prior to release could increase its efficacy towards the pest.

scholarly journals Physical and Chemical Traits of Grape Varieties Influence Drosophila suzukii Preferences and Performance

2021 ◽  
Vol 12 ◽  
Author(s):  
Lisa Weißinger ◽  
Katja Arand ◽  
Evi Bieler ◽  
Hanns-Heinz Kassemeyer ◽  
Michael Breuer ◽  
...  
Keyword(s):  
Chemical Properties ◽  
Epicuticular Wax ◽  
Pest Species ◽  
Cuticular Waxes ◽  
Drosophila Suzukii ◽  
Offspring Performance ◽  
Chemical Traits ◽  
Epicuticular Wax Layer ◽  
Grape Varieties ◽  
Physical And Chemical

The cuticle-covered surface forms the interface between plant parts, including fruits, and their environment. The physical and chemical properties of fruit surfaces profoundly influence plant-frugivore interactions by shaping the susceptibility and suitability of the host for the attacker. Grapevine (Vitis vinifera, Vitaceae) serves as one of the various host plants of the spotted wing drosophila, Drosophila suzukii Matsumura (Diptera: Drosophilidae), which is invasive in several parts of the world and can cause major crop losses. The susceptibility of wine towards this pest species differs widely among varieties. The objective of our study was to identify physical and chemical traits of the berry surface that may explain the differences in susceptibility of five grape varieties to D. suzukii. Both preferences of adult D. suzukii and offspring performance on intact versus dewaxed (epicuticular wax layer mechanically removed) grape berries were investigated in dual-choice assays. Moreover, the morphology and chemical composition of cuticular waxes and cutin of the different varieties were analyzed. Bioassays revealed that the epicuticular wax layer of most tested grape varieties influenced the preference behavior of adult flies; even less susceptible varieties became more susceptible after removal of these waxes. In contrast, neither offspring performance nor berry skin firmness were affected by the epicuticular wax layer. The wax morphology and the composition of both epi- and intracuticular waxes differed pronouncedly, especially between more and less susceptible varieties, while cutin was dominated by ω-OH-9/10-epoxy-C18 acid and the amount was comparable among varieties within sampling time. Our results highlight the underestimated role of the epicuticular surface and cuticle integrity in grape susceptibility to D. suzukii.

The neurology of professional performance

2016 ◽  
Vol 15 (4) ◽  
pp. 168-173 ◽  
Author(s):  
Liaquat Lal
Keyword(s):  
Human Brain ◽  
Intrinsic Motivation ◽  
Employee Engagement ◽  
Management Strategies ◽  
Paradigm Shifts ◽  
Content Type ◽  
Management Approaches ◽  
And Performance ◽  
The Impact ◽  
Creativity And Innovation

Purpose This paper aims to explore the impact on workplace performance and employee development of economic, technological, demographic and socio-political drivers, the consequential shift in job role design from an algorithmic to a heuristic model, and the importance of adopting management approaches that enhance intrinsic motivation, creativity and innovation. Design/methodology/approach The paper reviews findings from research into intrinsic motivation, Neuroleadership (including circumstances that trigger neurological responses in the limbic system in response to the threat of social pain) and the work of the psychologist, Mihaly Csikszentmihalyi, to explore possible approaches to performance leadership that reflect insights from neurology into the actions and reactions of the human brain. Findings The article proposes a classification of employees that reflects their location on two axes: the development challenge faced and pressure experienced in doing so. In the case of three (out of a total of four) classifications where performance may prove to be either unsatisfactory or unsustainable, management strategies, styles and approaches to improve individual and organisational performance and employee engagement are suggested. Originality/value As the nature of both work and the workforce evolve, management approaches that focus on inspiring rather than controlling performance will be of greater organisational benefit. By acknowledging these paradigm shifts and drawing on recently learning about human brain function, revised approaches to people management and performance leadership can help organisations to optimise performance and build and maintain workplace environments in which creativity and innovation are more likely to flourish.

Non-destructive determination of grape berry sugar concentration using visible/near infrared imaging and possible impact on wine quality

2015 ◽  
Vol 82 (12) ◽  
Author(s):  
Magali Lafontaine ◽  
Zrinka Bockaj ◽  
Maximilian Freund ◽  
Kai-Uwe Vieth ◽  
Christian Negara ◽  
...  
Keyword(s):  
Regression Model ◽  
Near Infrared ◽  
Infrared Imaging ◽  
Pinot Noir ◽  
Hyperspectral Images ◽  
Sugar Concentration ◽  
Wine Quality ◽  
Tannin Concentration ◽  
Grape Varieties ◽  
The Impact

AbstractReducing heterogeneity in harvest material would be beneficial for wine quality and this goal may be achieved through advanced berry sorting systems. The general aim was to assess if a relationship could be found between sugar concentration and hyperspectral images. Grapes were picked at different stages of maturity and the berries were sorted according to their size and density. Hyperspectral images of the berry subsamples were obtained in the vis/NIR wavelength range with a complete spectrum from 400 nm to 2500 nm. Our results showed that vis/NIR can be used to improve the segregation of berries from all tested grape varieties based on their sugar concentration. All berries from all 12 grape varieties were used to train the regression model and the predictive power was tested on all each grape variety separately, while later validated on each variety separately, proving the possibility of using a general regression model with constant parameters to predict sugar concentration. Finally, the impact on quality was tested for red wines. Pinot noir berries with higher sugar concentrations presented more color since anthocyanin concentration was higher. Nevertheless, tannin concentration in skins and seeds tended to decrease. Berries with higher sugar concentration resulted in wines with higher anthocyanin and lower tannin concentration.

Intergroup Threat and Outgroup Attitudes

2013 ◽  
Vol 44 (5) ◽  
pp. 311-319 ◽  
Author(s):  
Marco Brambilla ◽  
David A. Butz
Keyword(s):  
Gay Men ◽  
Social Group ◽  
Welfare Recipients ◽  
Intergroup Attitudes ◽  
Social Policies ◽  
Intergroup Threat ◽  
Economic Threat ◽  
The Impact ◽  
General Climate

Two studies examined the impact of macrolevel symbolic threat on intergroup attitudes. In Study 1 (N = 71), participants exposed to a macrosymbolic threat (vs. nonsymbolic threat and neutral topic) reported less support toward social policies concerning gay men, an outgroup whose stereotypes implies a threat to values, but not toward welfare recipients, a social group whose stereotypes do not imply a threat to values. Study 2 (N = 78) showed that, whereas macrolevel symbolic threat led to less favorable attitudes toward gay men, macroeconomic threat led to less favorable attitudes toward Asians, an outgroup whose stereotypes imply an economic threat. These findings are discussed in terms of their implications for understanding the role of a general climate of threat in shaping intergroup attitudes.

The Impact of Property Characteristics on Economic Performance of Russian Industrial Enterprises

2005 ◽  
pp. 53-68 ◽  
Author(s):  
R. Kapeliushnikov ◽  
N. Demina
Keyword(s):  
Detailed Analysis ◽  
Economic Performance ◽  
Ownership Concentration ◽  
Corporate Sector ◽  
Concentrated Ownership ◽  
Industrial Enterprises ◽  
Russian Industry ◽  
Control Premium ◽  
And Performance ◽  
The Impact

The paper provides new survey evidence on effects of concentrated ownership upon investment and performance in Russian industrial enterprises. Authors trace major changes in their ownership profile, assess pace of post-privatization redistribution of shareholdings and provide evidence on ownership concentration in the Russian industry. The major econometric findings are that the first largest shareholding is negatively associated with the firm’s investment and performance but surprisingly the second largest shareholding is positively associated with them. Moreover, these relationships do not depend on identity of majority shareholders. These results are consistent with the assumption that the entrenched controlling owners are engaged in extracting "control premium" but sizable shareholdings accumulated by other blockholders may put brakes on their expropriating behavior and thus be conductive for efficiency enhancing. The most interesting topic for further more detailed analysis is formation, stability and roles of coalitions of large blockholders in the corporate sector of post-socialist countries.

The Impact of Women’s Employment on Marital Stability in Qatar Society

2019 ◽  
Vol 10 (2) ◽  
pp. 144-151
Author(s):  
Noora Ahmed Lari ◽  
Keyword(s):  
Work Motivation ◽  
Marital Stability ◽  
Female Employment ◽  
Social Constraints ◽  
Primary Data ◽  
Family Policies ◽  
Insufficient Time ◽  
And Performance ◽  
The Impact ◽  
The Relationship

The State of Qatar has implemented several family policies in order to improve the wellbeing of Qatari families and ensure fair distribution of development benefits for both men and women. However, there is a linkage between female employment outside the home and instability in the marriages of Qatari families. This paper investigates the impact of female employment on marital stability, based on the results of primary data collected in Qatar, a questionnaire that consisted of several sections such as challenges in the workplace, supervisor, family and spouse relations, work motivation and performance. Of the 824 questionnaires that were returned, 807 were completed and valid for analysis. Regression analysis and an ANOVA test have been used to test the relationship between the variables. The results of the research have produced mixed findings about how wives’ employment increases marital instability and have yielded few significant differences on mean scores of discuss on work demands, insufficient time together, housework, financial matters, communication, relatives and rearing children. The results indicates that in general Qatar working women face several challenges in relation to their marital life as part of cultural and social constraints.

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