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Interpersonal ties influencing strategic decisions regarding inter-firm partnerships
The agri-food industries changed from vertically integrated supply chains towards vertical cooperating networks. In this context, inter-firm partnerships are seen as a possible tool to address changing markets and competition. Within strategic management, inter-firm partnerships are valued as a potential source of competitive advantage, which ascribes importance to the strategic management of partnerships. In the underlying classical cooperation theory, business cooperation decisions are assumed to be made rationally. Initial empirical studies show that managers have a personal influence on strategic decisions in business cooperation and that their decisions are not always in line with the common rationality assumptions in economics. Preliminary studies show initial "softer" or even "non-economic" interpersonal factors such as heuristics, biases, emotions, personality traits, or norms that can mitigate rationality and impact decisions in strategic collaborations made by managers. Human agents and their influence on strategic relationship management and intrafirm-, interfirm- and network-level outcomes are put into the research center of this study. Specifically, this thesis aims to explore whether managers (can) take an individual influence on strategic decision-making in B2B cooperation relations. Furthermore, it aims to analyze and identify which personal characteristics factors play a role during the decision-making process regarding inter-firm partnerships in the agri-food industry.
First empirical studies have evidenced that interaction – or in other words, the influence of managers – is a critical process in developing strategic buyer-seller relationships in B2B relations. I have argued that personal characteristics exist, and they influence decisions in inter-firm cooperation. An additional level, namely the personal-level, has to be explicitly included in the strategic chain management framework. Four general research expectations on which personal characteristics influence decision-making in inter-firm partnerships were derived.
As a consequence of the currently limited literature base I conducted two exploratory and qualitative studies in the form of expert interviews to first identify and prioritize the most critical driving personal influences on mangers in the German wine industry. Together, these two studies served as the basis for developing the research expectations and the main study in the form of factorial surveys. The study's statistical population size includes all companies that engage in grape-buying relationships (in Germany) to produce wine commercially (roughly 9,000 firms). The sample size based on the number of respondents is 203, but based on the judgments, the sample size is 602 judgments, as each respondent judged several items. After a descriptive statistical analysis, the Partial Least Squares (PLS) technique, in particular the multi-group analysis was used to evaluate the results.
The most important finding is that managers’ personal characteristics influence strategic decisions in chain management, particularly on mechanisms to manage cooperation. Furthermore, in this study, the characteristics of fairness, escalation of commitment, overconfidence, and representation heuristic significantly impacted some of the power and trust statements. Thus, focal firms have to consider and develop appropriate mechanisms to address and manage personal influences. Secondly, it was shown that various personal characteristics influence chain management decisions simultaneously and with different intensities in a positive or negative manner.
SUMMARY
Lager yeasts are hybrid organisms that originated by cell-fusion of two species of the genus Saccharomyces, S. cerevisiae and S. eubayanus. Post-hybridization events such as copy number variations (CNV), chromosome loss, reciprocal translocations or inter-chromosomal rearrangements can affect genome size, ploidy or sporulation efficiency. In polyploidy hybrids, the presence of multiple alleles of one gene complicates functional studies that rely on genome manipulation, e.g. gene deletions. Most yeast genetic engineering methods are based on the yeast homologous recombination (HR) machinery, which works excellently in S. cerevisiae but has a low efficiency in lager yeasts.
In this thesis, I developed a strategy to improve the HR efficiency of lager yeast allowing short-flank (sf) PCR-based gene targeting. HR efficiency was successfully improved by overexpressing RAD51, which encodes a key regulator of the HR pathway that performs the search for complementary DNA strands during recombination. The successful improvement of sf PCR-based gene targeting in lager yeast was demonstrated by targeting the S. cerevisiae-derived loci of ADE2 and HSP104 in the allotetraploid lager yeast Weihenstephan 34/70. This technology can now be used to facilitate genetic engineering in lager yeast, e.g. by altering the expression of specific genes involved in wort fermentation and flavor production.
Other mechanisms of genome evolution are by uptake of DNA through horizontal gene transfer or introgression. These were studied in more detail in a cider yeast strain. Genome sequencing revealed that the strain represents a particular Saccharomyces uvarum isolate. Interestingly, in this strain we identified the acquisition of ~100 kb of S. eubayanus DNA harboring 54 gene ORFs at chromosome XIV. An analysis based on DNA polymorphisms suggests that a lager yeast strain is likely parental donor of this DNA rather than a S. eubayanus strain. An additional DNA insertion with high identity to Torulaspora microellipsoides was found at chromosome XII. The introgression of this specific DNA region was previously observed in several wine yeast strains. It harbors 19 wine – related genes such as FOT1/FOT2, encoding the fungal oligopeptide transporter Fot, which confers advantages in nitrogen utilization. Strikingly, the S. uvarum cider isolate outcompetes in standard and cold fermentation regimes, S. cerevisiae EC1118, which is considered a workhorse of the wine industry.
Beer and wine yeasts are characterized by their flocculation properties at the end of fermentation. Flocculation is the ability to produce cell-flocs, a critical trait for industrial yeast, which enables facile separation of cells from the green beer. To implement non-conventional yeast (NCY) in an existing brewing process, these yeasts need to be adaptable to the current brewing technology. Therefore, in this thesis, the flocculation properties of a NCY, Saccharomycopsis fermentans, were characterized. I could show that flocculation of S. fermentans is Ca2+- dependent like in S. cerevisiae. By PacBio genome sequencing, based on the similarity to the FLO1/5/9 genes of S. cerevisiae and the ALS gene family of Candida albicans, 34 flocculation genes were identified in S. fermentans, and termed FAS (for FLO/ALS-like sequences). Moreover, FAS genes are found to be located at sub telomeric and telomeric regions as are the S. cerevisiae flocculation genes. “Telologs” – orthologous or paralogous genes located at telomers – was a novel term introduced to identify genes which share an evolutionary conserved genomic location.
Blattseneszenz stellt bei Pflanzen einen genetisch geregelten, komplexen Alterungsprozess dar. Sie wird durch die Kombination von Umwelt- und Altersfaktoren ausgelöst und dient dem Recycling von Nährstoffen. Charakteristisch für die Blattseneszenz sind eine erhöhte Expression von Seneszenz-assoziierten Genen (SAGs), der Abbau von Chlorophyll und die Rückverlagerung von Nährstoffen, insbesondere von Stickstoff (N). Bei der Weinrebe Vitis vinifera dient N nicht nur dem pflanzlichen Wachstum, sondern auch der Hefeernährung während der alkoholischen Gärung des Mostes. Der Gehalt an hefeverfügbarem N (YAN) in der Beere hängt sowohl von der N-Verfügbarkeit des Standorts, als auch von der N-Einlagerung während der Reife ab. Durch den Klimawandel erfolgen Traubenreife und Blattseneszenz zunehmend zeitlich entkoppelt, wodurch im Most der in nördlichen Anbaugebieten spätreifenden Rebsorte Vitis vinifera cv. Riesling der für eine gute Vergärbarkeit empfohlene Zielwert von 150 mg/L YAN nicht erreicht wird und das Risiko von Gärproblemen steigt. Daher wurde in dieser Arbeit auf zwei Standorten mit unterschiedlicher N-Verfügbarkeit und in zwei Jahren untersucht, ob durch eine Behandlung mit Ethephon oder UV-C vor der Lese Blattsenszenz induziert, und durch Umverlagerung des remobilisierten N in die Beere eine ausreichende Konzentration an YAN im Most erzielt werden kann. Die Ethephon-Behandlung induzierte Blattseneszenz zuverlässig und schnell, ihre N-Remobilisierung wie auch ihre Genexpression glichen der von natürlicher Seneszenz. Die UV-C-Behandlung erzeugte ebenfalls Seneszenz-Symptome, sie erreichte jedoch nicht die Effektivität der Ethephon-induzierten und der natürlichen Seneszenz. Auf dem Standort mit geringer N-Verfügbarkeit konnte durch die Ethephon-Behandlung die YAN-Konzentration im Most gesteigert werden, durch die UV-C-Behandlung hingegen nicht. Auf dem Standort mit guter N-Verfügbarkeit hatte keines der beiden Verfahren einen Effekt auf die Most-N-Versorgung. Die erreichten YAN-Steigerungen verbesserten die Vergärbarkeit, obwohl der Zielwert von 150 mg/L in keinem Fall erreicht wurde. Die zur Sicherstellung einer guten Gärleistung empfohlene YAN-Konzentration im Most ist daher kritisch zu überprüfen.
Grapevine physiology and berry composition are highly influenced by abiotic factors, and this, in turn, affects wine composition and aroma. Primary metabolites, like sugars and acids, and also secondary metabolites, like phenols and terpenes, are sensitive to climatic conditions. However, the developmental stage of the berries
and the environmental conditions within the bunch zone play a crucial role determining the different pathways of the metabolites and hence its concentration.
This study aimed to investigate the influence of abiotic factors on the composition of berries, juice and wine of Vitis vinifera L. cv. Riesling.
Field experiments were carried out in an experimental site of Hochschule Geisenheim University [Eibinger Magdalenenkreuz, Germany (49° 59’20’’ N; 7° 55’56’’ E)] using Riesling [clone 198–25Gm; grafted on rootstock SO4 Gm47 (Vitis berlandieri x V. riparia)]. In a non-irrigated vineyard, planted in 2007, the vines were trained to a vertical shoot position canopy system. The impact of global
warming and rising temperature was one of the main questions of this thesis, and was simulated by an open heating system (OHS) in the vineyard. The tent-like construction passively heated the bunch zone. The effect of higher sun exposure on berries was trialed by the defoliation of the bunch zone at different stages of berry
development. The removal of leaves around bunches is commonly used in coolclimate viticulture to improve the health status of berries and influence the aroma profile. Due to the increasing numbers of sunshine hours as well as the rising temperatures caused by climate change, the question then arises if in future defoliation practices will be the method of choice. Additionally, and in contrast, some
bunches were placed in light-excluding boxes to simulate full shading.
On days with high radiation, the open heating system clearly elevated temperatures compared to the control and the defoliation treatments. In the bunch zone above the open heating system, the air temperature was 4 °C higher compared to the other treatments. Inside the open heating system, the temperature was up to 13 °C higher.
On days with low radiation, there was a minimal temperature difference between the treatments.
The porosity of the bunch zone was quantified by a novel approach using lightsensitive films which provide a simple and accurate method for characterizing light conditions and quantifying cumulative radiation within the canopy. Different lightsensitive
film qualities allow the measurement over a short period (3-7 days) or a more extended period (1-3 weeks). One of the significant advantages of this method will be that simultaneous measurement of several points will be possible.
The health status of the berries was improved by defoliation and the infection (incidence and severity) of Botrytis cinerea reduced compared to the control providing a faster drying of bunches after morning dew or rainfall. Similarly, the OHS promoted airflow inside the bunch zone, causing same effects.
Higher temperatures significantly reduced the berry weight, with the effect more pronounced if higher temperatures occurred before véraison. Berries grown under higher temperatures showed lower total soluble solids and the glucose to fructose ratio was impacted by lower glucose concentrations. A change in the glucose to fructose ratio will be of relevance for the fermentation since most yeasts prefer glucose over fructose. Defoliation treatment had no impact on the total soluble solids. In contrast, intense radiation or shading did not affect the berry size while extreme shading of the bunches reduced total soluble solids.
Tartaric acid was not significantly influenced by higher temperatures or radiation, but malic acid concentrations strongly declined under warmer conditions. This decreased the total acidity in juice and wine, which is of particular importance for the wine profile of Riesling. The defoliation practices showed only little effect on the acid concentrations whilst the extreme shading treatments strongly increased the acidity.
The analysis of phenols in berry skin was performed by high-performance liquid chromatography (HPLC) coupled to a photodiode array (PDA) detector and quantified with an external calibration. Flavonols, in particular, were influenced by higher sun exposure, with significantly higher flavonol concentrations found in the
defoliation treatments. The time point when defoliation was applied had only small effects on the final total flavonol concentration. On the other hand, when a sunny period occurred after véraison flavanols revealed high concentrations after defoliation. Sunny periods before véraison or a ripening period with low sunshine
hours did not increase the flavanol concentration compared to the control. No impact of the defoliation on the group of hydroxycinnamic acids, non-flavanoids, was The sensory assessment with small scale-vinifications was diverse. Only in the younger vintage, the panellists were able to detect differences in wines, which were mainly based on total acidity.
The influence of the treatments to the grapes, which were observed for primary and secondary metabolites in berries and juice, were found in wine as well. The only expectation was TDN. In wines, higher TDN concentrations were always detected for the late defoliation. The early defoliation contained higher TDN concentrations if a sunny period occurred before véraison. Also, elevated temperatures caused higher TDN levels in wine. The prediction of the precise temperature and light conditions influencing TDN will require detailed investigations.
A new approach was developed to analyse and quantify free and glycosidically bound monoterpenes and C13-norisoprenoids in berries, juice and wine. The sample volume was reduced by 90% and free analytes were directly analysed from the matrix with only little sample preparation. This simplified the analysis, saved time
and made the use of organic solvents and solid-phase extraction cartridges redundant. The method was validated and compared to other methods in literature.
In juice and wine 15 monoterpenes and four C13-norisoprenoids could be analysed simultaneously and the typically concentration ranges of the samples were covered.
Past adoption research has focused on new ideas, services and consumer durable goods where the first purchase is sufficient to be regarded as the act of adoption. Adoption studies rarely expand its application on new consumer packaged goods (CPGs) where subsequent repeat purchases are in high demand. Every year, the CPG industry spends a large amount of budget on developing and launching new products into the market in order to generate competitiveness, hence yielding financial growth. Despite the fact that new products have been carefully designed and tested before launch, the majority of them still fail. Consumers may talk the talk in pre-market tests but walk the walk after product launch. Such a gap between stating an intention for the future and taking action in the proximal may come from a lack of understanding the dynamic nature of the adoption process.
Consequently, this thesis investigates the process and antecedents of adopting new CPGs, which is also known as fast moving consumer goods (FMCGs). This thesis aims to unveil how the influence of adoption antecedents change along the process. Three research questions are raised:
1) What is the adoption process of new CPGs?
2) What are the key factors of adopting a specific product category in an emerging market?
3) How do the effect sizes of these adoption factors change along the process?
The wine category in China is selected to be the research context. The exploratory sequential mixed-method approach is designed in two phases. In Study 1, twenty-six face-to-face, in depth interviews with both wine adopters and non-adopters were conducted in two Chinese cities to outline the adoption process and refine the key adoption antecedents. Then the key adoption antecedents were further discussed and subjected to a hypothetical model. In Study 2, an online survey was launched to collect data from 1,567 alcohol consumers nationwide. Structural equation modelling was applied in testing the effect sizes of the adoption antecedents and corresponding process dynamic effects. The results indicate three major discoveries.
1) The adoption of new CPGs is a long process concerning repeat purchases or consumptions after the first trial.
Unlike Rogers’ process model (Rogers 2003), there are not many cognitive considerations before adoption behaviour occurs. The subsequent repeat purchases after the first trial are more decisive on how far a consumer can reach along the adoption journey. After the first trial, two milestone intermediate stages were identified: increasing exposure and reinforcement. Consumers start to build up the association between products and consumption occasions at the increasing exposure stage. Later into the reinforcement stage, these associations expand to more frequent consumption occasions. This empirical finding highlights the importance of understanding post-trial repeat purchases for the CPG industry and research, not just the first purchase.
2) Adoption intention is different to adoption behaviour.
Different adoption outcomes have been used interchangeably in adoption research and in pre- market tests, especially adoption intention and behaviour. This study finds that adoption intention associates weakly with adoption behaviour. These two different adoption outcomes are influenced by different antecedents. Personal traits are more influential on adoption intention; while consumption behaviour and relative advantages of the new product drive adoption behaviour. This discovery suggests that adoption variables from different time points of the process should not be used interchangeably or utilise one to predict the other one. Furthermore, adoption variables should be selected carefully according to the antecedents of interest.
3) The influence of past consumption behaviour on adoption behaviour is dynamic along the adoption process.
This discovery adds one more empirical evidence that adoption antecedents exhibit different influence on adoption at different behavioural stages. It sheds light on the process dynamic effect of adoption antecedents and responses to the call of process-oriented studies by adoption researchers.
Wine tourism is a growing niche market around the world. Germany seems to offer an ideal platform for this promising market. However, there is very limited knowledge about the economic significance of wine tourism in Germany and about understanding visitors’ needs and expectations. By proposing a framework for three different studies across all 13 German wine regions, including both the travelers’ and the wineries’ perspective, this thesis aims to alter the understanding of wine tourism in Germany. The three main research questions derived from a survey of the literature (see Chapter 1) are:
1. What differentiates wine tourists in Germany from other tourist segments?
2. How large is the economic impact of wine tourism in Germany?
3. How relevant is wine tourism in Germany from a winery operators’ perspective?
In order to separate wine tourists from other tourist segments, a quantitative study with 4,478 visitors to wine regions was carried out. By interviewing visitors at “wine-neutral” locations such as city centers or cultural sites, this approach differed from previous research. After segmentation, travelers were divided into wine tourists and other tourist segments. Then, a modified multiplier model was developed that allows measuring the economic impact of wine tourism. Finally, to include the wineries’ perspective, 199 qualitative in-depth interviews and 703 quantitative online questionnaires were collected and analyzed. It is the aim of the winery surveys to reveal the relevance and main challenges of wine tourism in Germany.
Results show that 7.2 million wine tourists, of whom 89% are Germans, visit the country’s wine regions each year. For them, tasting wine, enjoying nature and combining food and wine experiences are the main motivating factors for visiting a wine region. Wine tourism has a disproportionately large economic impact of EUR 5.0 billion annually, contributing to the income of 71,846 people. From an average winery operator’s perspective, wine tourism accounts for 24% of company sales. Despite an increasing demand in wine-touristic activities, the number of wineries, as well as restaurants, is declining which reduces the attractiveness for culinary-focused wine tourists. To successfully develop wine tourism in Germany, there is a clear need for collaboration among stakeholders. Furthermore, the preservation of cultural landscapes plays an important role in attracting visitors.
This thesis advances the understanding of wine tourism in Germany from a visitor’s as well as a winery’s point of view. The approaches developed for segmenting wine tourists and for assessing the economic impact of wine tourism can be applied in any wine region of the world. They can also be transferred to other forms of special-interest tourism (e.g. alpine tourism and culinary tourism). The findings and discussions can be used for teaching students and training stakeholders at the regional, entrepreneurial and personal level. Wine tourism could help to balance inequalities between rural and urban areas in terms of income and employment levels. This, combined with the preservation of natural resources and cultural landscapes, could lead to sustainable regional development in the German wine regions.