Staff Publications

Staff Publications

  • external user (warningwarning)
  • Log in as
  • language uk
  • About

    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

    We have a manual that explains all the features 

    Records 1 - 20 / 268

    • help
    • print

      Print search results

    • export
      A maximum of 250 titles can be exported. Please, refine your queryYou can also select and export up to 30 titles via your marked list.
    Check title to add to marked list
    Differential responses to salt stress in ion dynamics, growth and seed yield of European quinoa varieties
    Jaramillo Roman, Viviana ; Toom, Leonardus A. den; Castro Gamiz, Carlos ; Pijl, Niels van der; Visser, Richard G.F. ; Loo, Eibertus N. van; Linden, Gerard van der - \ 2020
    Environmental and Experimental Botany 177 (2020). - ISSN 0098-8472
    Chenopodium quinoa - Naexclusion - RGR - Salt stress tolerance - Survival and growth

    Quinoa is a nutritious seed crop with a great potential to grow in saline soils. Here, we studied ion concentrations in quinoa tissues throughout the life cycle of the plant, and linked ion dynamics to responses in growth parameters, seed yield and efficiency of photosynthesis under salinity (0–400 mM NaCl). Ion dynamics changed from high ion exclusion (>99 %, root contents lower than root medium and low accumulation of ions in the leaves) before flowering, to a build-up of ions during seed filling. This indicates a change in strategy in maintaining the necessary gradient of water potential from the root medium to the leaves. K+ concentrations in leaves also increased by more than 100 % in response to prolonged severe salt stress, which may point to a role of this ion in leaf osmotic adjustment. Accumulation of ions in epidermal bladder cells did not contribute substantially to Na+-exclusion as it was less than 6 % of the total Na+ taken up in leaves. Growth under salt stress was mostly impaired by anatomical adaptations (reduced SLA), while initial light use efficiency (Fv/Fm) and NAR were not affected. The variety Pasto showed a “survival strategy” to high salinity with higher ion exclusion and a higher reduction in transpiration than the other varieties, at the expense of lower biomass and seed yield.

    Sustainable bottled water : How nudging and Internet Search affect consumers’ choices
    Grebitus, Carola ; Roscoe, Rod D. ; Loo, Ellen J. Van; Kula, Irfan - \ 2020
    Journal of Cleaner Production 267 (2020). - ISSN 0959-6526
    Artesian water - Beverage - Information search - lab vs. online study - Mountain spring water - Online search - Plant-based plastic - Post-consumer waste plastic

    This study examined differences in consumer preferences and willingness to pay for sustainable bottled water based on pro-environmental guidance, Internet information search, and research setting (i.e., laboratory or online). Specifically, we investigated willingness to pay for bottled water produced with plant-based plastics and post-consumer waste plastics. Insight into willingness to pay (i.e., preferences and acceptance) for novel plastics is valuable given the potential impact of such materials regarding cleaner production of food and non-food products. Results from mixed logit models showed that searching for information increased the likelihood that consumers would choose sustainable plastic water bottles over less sustainable options, and the effect was magnified when consumers were primed to make environmentally friendly choices. Findings also revealed a considerable amount of preference heterogeneity with regard to the type of water product or type of plastic used to manufacture the bottles. Similar results were reflected in the willingness to pay. In addition, preference and willingness to pay were generally higher in the lab setting compared to the online setting. Overall, pro-environmental guidance can nudge individuals towards making more sustainable choices even if it comes at a higher cost. For stakeholders and policy makers with interests in the beverage industry, observed findings can inform recommendations for facilitating more sustainable consumer behavior.

    Measurement and genetic architecture of lifetime depression in the Netherlands as assessed by LIDAS (Lifetime Depression Assessment Self-report)
    Fedko, Iryna O. ; Hottenga, Jouke Jan ; Helmer, Quinta ; Mbarek, Hamdi ; Huider, Floris ; Amin, Najaf ; Beulens, Joline W. ; Bremmer, Marijke A. ; Elders, Petra J. ; Galesloot, Tessel E. ; Kiemeney, Lambertus A. ; Loo, Hanna M. Van; Picavet, H.S.J. ; Rutters, Femke ; Spek, Ashley Van Der; De Wiel, Anne M. Van; Duijn, Cornelia Van; Geus, Eco J.C. De; Feskens, Edith J.M. ; Hartman, Catharina A. ; Oldehinkel, Albertine J. ; Smit, Jan H. ; Verschuren, W.M.W. ; Penninx, Brenda W.J.H. ; Boomsma, Dorret I. ; Bot, Mariska - \ 2020
    Psychological Medicine (2020). - ISSN 0033-2917
    LIDAS - Lifetime Depression Assessment Self-report - major depressive disorder - online assessment tool - prevalence

    BackgroundMajor depressive disorder (MDD) is a common mood disorder, with a heritability of around 34%. Molecular genetic studies made significant progress and identified genetic markers associated with the risk of MDD; however, progress is slowed down by substantial heterogeneity as MDD is assessed differently across international cohorts. Here, we used a standardized online approach to measure MDD in multiple cohorts in the Netherlands and evaluated whether this approach can be used in epidemiological and genetic association studies of depression.MethodsWithin the Biobank Netherlands Internet Collaboration (BIONIC) project, we collected MDD data in eight cohorts involving 31 936 participants, using the online Lifetime Depression Assessment Self-report (LIDAS), and estimated the prevalence of current and lifetime MDD in 22 623 unrelated individuals. In a large Netherlands Twin Register (NTR) twin-family dataset (n 18 000), we estimated the heritability of MDD, and the prediction of MDD in a subset (n = 4782) through Polygenic Risk Score (PRS).ResultsEstimates of current and lifetime MDD prevalence were 6.7% and 18.1%, respectively, in line with population estimates based on validated psychiatric interviews. In the NTR heritability estimates were 0.34/0.30 (s.e. = 0.02/0.02) for current/lifetime MDD, respectively, showing that the LIDAS gives similar heritability rates for MDD as reported in the literature. The PRS predicted risk of MDD (OR 1.23, 95% CI 1.15-1.32, R2 = 1.47%).ConclusionsBy assessing MDD status in the Netherlands using the LIDAS instrument, we were able to confirm previously reported MDD prevalence and heritability estimates, which suggests that this instrument can be used in epidemiological and genetic association studies of depression.

    CRISPR, camelina, cut! : Valorizing genome-edited Camelina sativa for a bio-based economy
    Belle, Jarst van - \ 2020
    Wageningen University. Promotor(en): R.G.F. Visser, co-promotor(en): E.N. van Loo; J.G. Schaart. - Wageningen : Wageningen University - ISBN 9789463952842 - 169

    The European oleochemical industry uses more and more renewable bio-based medium-chain fatty acids (MCFA) and longer mono-unsaturated fatty acids (MUFA) as sources for a wide range of applications such as plastics, lubricants and polymer building blocks, and can in theory completely replace the fossil-based petrochemical industry. The raw materials for these fatty acids consist of imported plant oils (e.g. palm kernel oil). The increased demand of these oils for oleochemical use, however, cannot sustainably be fulfilled by producing more palm kernel oil as such increase in production would most likely only be possible by converting tropical rainforest to plantations. The main aim of this thesis is to generate novel genetic variation by deploying CRISPR/Cas9 to camelina to in the end reduce the dependency of Europe on imported palm kernel and coconut oils and fatty acids. This should help us considerably in achieving a more sustainable bio-based economy.

    Farmers’ willingness to adopt late blight-resistant genetically modified potatoes
    Steur, Hans De; Loo, Ellen J. Van; Maes, Jasmien ; Gheysen, Godelieve ; Verbeke, Wim - \ 2019
    Agronomy 9 (2019)6. - ISSN 2073-4395
    Adoption - Attitude - Belgium - Farmer - Genetic modification - GM - Potato

    The commercialization of genetically modified (GM) crops remains highly contested in the European Union (EU). While research has mainly focused on public and consumer opinions, few studies have investigated farmers’ reactions towards such crops. This study aims to determine farmers’ willingness to adopt a late blight-resistant (LBR) GM potato cultivar (Bintje) in Flanders, Belgium (n = 384). The findings demonstrate that more than half (54.7%) of the farmers have the intention to adopt this GM potato if it becomes available. Farmers’ willingness to adopt is mainly influenced by ethical concerns about Genetically Modified Organisms (GMOs) (negative) and perceived economic benefits of LBR GM potatoes (positive). Knowledge about GM technology decreases the likelihood of being indifferent, as compared to being willing to adopt or being opposed. As such, efforts to improve knowledge alone would not be considered an effective strategy to improve adoption rates among farmers. Socio-economic concerns about GMOs, environmental benefit perceptions of LBR GM potatoes, and socio-demographic and farm variables were not significant as potential determinants of farmers’ likelihood to adopt this GM potato. Our findings lend support to a potentially favorable climate to introduce this GM potato in Flanders, Belgium, an EU region where opt-out measures to restrict cultivation of approved GM crops were not taken.

    Biogrondstoffen : programmeringsstudies Landbouw, Water en Voedsel
    Elbersen, B. ; Ammerlaan, I. ; Klein Lankhorst, R. ; Matser, A. ; Trindade, L. ; Lesschen, J.P. ; Spijker, J. ; Meer, I. van der; Broese, J. ; Nabuurs, G.J. ; Wichers, H. ; Krimpen, M. van; Arets, E. ; Jansen, H. ; Loo, R. van; Veldkamp, T. ; Steins, Nathalie ; Smith, Sarah - \ 2019
    Wageningen : Wageningen University & Research - 41
    Molecular characterization of Ecuadorian quinoa (Chenopodium quinoa Willd.) diversity : implications for conservation and breeding
    Salazar, Juan ; Jaramillo Roman, Viviana ; Gutierrez, Bernardo ; Loo, E.N. van; Lourdes Torres, María de; Torres, Andrés Francisco - \ 2019
    Euphytica 215 (2019)3. - ISSN 0014-2336
    Breeding - Ecuador - Genetic diversity - Population structure - Quinoa - SSR

    Quinoa (Chenopodium quinoa Willd.) is recognized as an important crop to improve global food security. It has gained international recognition because of the nutritional value of its seeds and its broad agronomic resilience. Although several studies have attempted to characterize the genetic diversity of quinoa, none have focused on evaluating germplasm from Ecuador; the latter considered a relevant subcenter of diversity for the species. In this study, 84 accessions representing the species’ cultivated range in the Ecuadorian Andes were characterized using 15 species-specific SSR markers. The extent of allelic richness (196 alleles) and genetic heterozygosity (H E = 0.71) detected for these accessions demonstrate that Ecuadorian quinoa is highly diverse. Phenetic analyzes structured Ecuadorian germplasm into 3 subgroups; each containing genotypes from all surveyed provinces. Average expected heterozygosity was high for all 3 subgroups (0.53 ≤ H E ≤ 0.72), and Nei-pairwise comparisons showed significant genetic divergence among them (0.31 ≤ Nei DST ≤ 0.84). The lack of a clear geographic pattern in the genetic structure of Ecuadorian quinoa led us to believe that the 3 reported subgroups constitute independent genetic lineages representing ancestral landrace populations which have been disseminated throughout Ecuador via informal seed networks. Nevertheless, a Wilcoxon test showed that at least one subgroup had been subject to intensive inbreeding and selection; and possibly corresponds to the local commercial variety INIAP-Tunkahuan. Our results show that ancestral quinoa diversity in Ecuador has prevailed despite the introduction of commercial varieties, and should be preserved for future use in breeding programs.

    Learning to become an entrepreneur in unfavourable conditions : The case of new entrants in the context of the Greek debt-crisis
    Karanasios, K. ; Lans, T. - \ 2019
    In: Multiple Dimensions of Teaching and Learning for Occupational Practice / Loo, Sai, Routledge, Taylor & Francis Group - ISBN 9781138585713 - p. 131 - 149.
    This chapter reports the results of a study that explored the learning process of a distinct group of learners, namely Greek new entrant agri-entrepreneurs, in the unfavourable entrepreneurial environment of the Greek crisis. To find out how this group formulates its learning during their journey towards a new occupation (entrepreneurship), semi-structured interviews were conducted with a sample of 18 agri-entrepreneurs. The interviews, which were carried out by building on the 3-P model of workplace learning using the critical incidents technique, elicited several factors that affected their entrepreneurial learning. Regarding the drivers of the learning process at the individual level, the results of this study gave prominence to the entrepreneurial agency of the participants as an amalgam of different opportunistic and necessity motives. As far it concerns the work environment influencing entrepreneurial learning, the data highlighted the importance of the so-called weak ties with external stakeholders, while they revealed a legal, regulatory and advisory system that is at least unsupportive and inappropriate for learning and entrepreneurship in general. From a process point of view, the results emphasised the importance of experimental-improvisational learning activities adopted by the entrepreneurs. Furthermore, they revealed the unexpectedly low use of Information and Communication Technologies for entrepreneurial learning. Finally, with regard to the outcomes of the learning process, the results accentuate the development of an entrepreneurial identity, where the entrepreneurs identify themselves as ecological, resource exploiting and cultural entrepreneurs. This chapter concludes by giving recommendations for further research and providing practical implications for those involved in work-related education, training and advisory support of entrepreneurs.
    Correction to: Molecular characterization of Ecuadorian quinoa (Chenopodium quinoa Willd.) diversity: implications for conservation and breeding
    Salazar, Juan ; Roman, Viviana Jaramillo ; Gutierrez, Bernardo ; Loo, Eibertus Nicolaas van; Lourdes Torres, María de; Torres, Andrés Francisco - \ 2019
    Euphytica 215 (2019)12. - ISSN 0014-2336

    Due to an unfortunate error of miscommunication, two of the co-authors of this manuscript were omitted from the original publication. The correct representation of the authors and their affiliations are listed here and should be treated as definitive. Juan Salazar1, Viviana Jaramillo Roman2, Bernardo Gutierrez1,3, Eibertus Nicolaas van Loo2, Mari´a de Lourdes Torres1, Andre´s Francisco Torres1,2 1. Laboratorio de Biotecnologi´a Vegetal, Colegio de Ciencias Biolo´gicas y Ambientales, Universidad San Francisco de Quito USFQ, Diego de Robles y Vi´a Interocea´nica, Cumbaya´, Ecuador 2. Wageningen UR Plant Breeding, Wageningen University and Research, PO Box 386, 6700 AJ Wageningen, The Netherlands 3. Department of Zoology, University of Oxford, 11a Mansfield Road, Oxford OX1 3SZ, UK Furthermore, the acknowledgments section has been adapted to match the changes in authorship. The corrected acknowledgements, presented below, are definitive: This research was funded with a Chancellor’s Grant (2015) from Universidad San Francisco de Quito USFQ (Quito-Ecuador). Germplasm access and research permit were granted by the Ministry of Environment of Ecuador (MAE-DNB-CM-2016- 0044). The authors would like to acknowledge the technical assistance offered by researchers at the Plant Biotechnology Laboratory (COCIBA, USFQ), as well as Dr. Leonardo Zurita for his assistance with georeferenced mapping. The authors would also like to acknowledge Dr. Gerard van der Linden (Wageningen University and Research) for supporting our efforts to search and collect quinoa germplasm throughout the Andes of Ecuador.

    Marginal agricultural land low-input systems for biomass production
    Cossel, Moritz Von ; Lewandowski, Iris ; Elbersen, Berien ; Staritsky, Igor ; Eupen, Michiel Van; Iqbal, Yasir ; Mantel, Stefan ; Scordia, Danilo ; Testa, Giorgio ; Cosentino, Salvatore Luciano ; Maliarenko, Oksana ; Eleftheriadis, Ioannis ; Zanetti, Federica ; Monti, Andrea ; Lazdina, Dagnija ; Neimane, Santa ; Lamy, Isabelle ; Ciadamidaro, Lisa ; Sanz, Marina ; Carrasco, Juan Esteban ; Ciria, Pilar ; McCallum, Ian ; Trindade, Luisa M. ; Loo, Eibertus N. Van; Elbersen, Wolter ; Fernando, Ana Luisa ; Papazoglou, Eleni G. ; Alexopoulou, Efthymia - \ 2019
    Energies 12 (2019)16. - ISSN 1996-1073
    Bio-based industry - Bioeconomy - Bioenergy - Biomass - Industrial crop - Low-input agriculture - MALLIS - Marginal land - Perennial crop - Sustainable agriculture

    This study deals with approaches for a social-ecological friendly European bioeconomy based on biomass from industrial crops cultivated on marginal agricultural land. The selected crops to be investigated are: Biomass sorghum, camelina, cardoon, castor, crambe, Ethiopian mustard, giant reed, hemp, lupin, miscanthus, pennycress, poplar, reed canary grass, safflower, Siberian elm, switchgrass, tall wheatgrass, wild sugarcane, and willow. The research question focused on the overall crop growth suitability under low-input management. The study assessed: (i) How the growth suitability of industrial crops can be defined under the given natural constraints of European marginal agricultural lands; and (ii) which agricultural practices are required for marginal agricultural land low-input systems (MALLIS). For the growth-suitability analysis, available thresholds and growth requirements of the selected industrial crops were defined. The marginal agricultural land was categorized according to the agro-ecological zone (AEZ) concept in combination with the marginality constraints, so-called 'marginal agro-ecological zones' (M-AEZ). It was found that both large marginal agricultural areas and numerous agricultural practices are available for industrial crop cultivation on European marginal agricultural lands. These results help to further describe the suitability of industrial crops for the development of social-ecologically friendly MALLIS in Europe.

    Explaining attention and choice for origin labeled cheese by means of consumer ethnocentrism
    Loo, Ellen J. Van; Grebitus, Carola ; Roosen, Jutta - \ 2019
    Food Quality and Preference 78 (2019). - ISSN 0950-3293
    Biodegradable packaging - Complex decision-making - Eye-tracking - Growth hormone labeling - rBST - Visual attention

    This study examines the relationship between consumer ethnocentrism, visual attention and choice for origin labeled cheese. It evaluates the impact of consumer ethnocentrism on preferences for domestic products, as well as, on the visual attention paid to the origin labeling during the decision-making. Using a choice experiment, this study investigates US respondents’ preferences for product attributes of cheddar cheese including country of origin (US, Mexico, Ireland), region of origin, hormone use, biodegradable packaging, and price. It provides empirical evidence that the level of consumer ethnocentrism among US consumers influences the preference for US labelled cheese and the visual attention to origin labeling. Specifically, higher consumer ethnocentrism leads to a higher preference for US cheese as compared to Irish cheese. Further, the study reveals that the level of consumer ethnocentrism affects visual attention paid to origin labeling. However, this is only the case in less complex decision situations, when there is little information on other product attributes.

    Supplementation of diet with non-digestible oligosaccharides alters the intestinal microbiota, but not arthritis development, in IL-1 receptor antagonist deficient mice
    Rogier, Rebecca ; Ederveen, Thomas H.A. ; Wopereis, Harm ; Hartog, Anita ; Boekhorst, Jos ; Hijum, Sacha A.F.T. Van; Knol, Jan ; Garssen, Johan ; Walgreen, Birgitte ; Helsen, Monique M. ; Kraan, Peter M. Van Der; Lent, Peter L.E.M. Van; De Loo, Fons A.J. Van; Abdollahi-Roodsaz, Shahla ; Koenders, Marije I. - \ 2019
    PLoS ONE 14 (2019)7. - ISSN 1932-6203

    The intestinal microbiome is perturbed in patients with new-onset and chronic autoimmune inflammatory arthritis. Recent studies in mouse models suggest that development and progression of autoimmune arthritis is highly affected by the intestinal microbiome. This makes modulation of the intestinal microbiota an interesting novel approach to suppress inflammatory arthritis. Prebiotics, defined as non-digestible carbohydrates that selectively stimulate the growth and activity of beneficial microorganisms, provide a relatively non-invasive approach to modulate the intestinal microbiota. The aim of this study was to assess the therapeutic potential of dietary supplementation with a prebiotic mixture of 90% short-chain galacto-oligosaccharides and 10% long-chain fructo-oligosaccharides (scGOS/lcFOS) in experimental arthritis in mice. We here show that dietary supplementation with scGOS/ lcFOS has a pronounced effect on the composition of the fecal microbiota. Interestingly, the genera Enterococcus and Clostridium were markedly decreased by scGOS/lcFOS dietary supplementation. In contrast, the family Lachnospiraceae and the genus Lactobacillus, both associated with healthy microbiota, increased in mice receiving scGOS/lcFOS diet. However, the scGOS/lcFOS induced alterations of the intestinal microbiota did not induce significant effects on the intestinal and systemic T helper cell subsets and were not sufficient to reproducibly suppress arthritis in mice. As expected, we did observe a significant increase in the bone mineral density in mice upon dietary supplementation with scGOS/lcFOS for 8 weeks. Altogether, this study suggests that dietary scGOS/lcFOS supplementation is able to promote presumably healthy gut microbiota and improve bone mineral density, but not inflammation, in arthritis-prone mice.

    UAV based soil salinity assessment of cropland
    Ivushkin, Konstantin ; Bartholomeus, Harm ; Bregt, Arnold K. ; Pulatov, Alim ; Franceschini, Marston H.D. ; Kramer, Henk ; Loo, Eibertus N. van; Jaramillo Roman, Viviana ; Finkers, Richard - \ 2019
    Geoderma 338 (2019). - ISSN 0016-7061 - p. 502 - 512.
    Hyperspectral - LiDAR - Quinoa - Remote sensing - Soil salinity - Thermography - UAV

    Increased soil salinity is a significant agricultural problem that decreases yields for common agricultural crops. Its dynamics require cost and labour effective measurement techniques and widely acknowledged methods are not present yet. We investigated the potential of Unmanned Aerial Vehicle (UAV) remote sensing to measure salt stress in quinoa plants. Three different UAV sensors were used: a WIRIS thermal camera, a Rikola hyperspectral camera and a Riegl VUX-SYS Light Detection and Ranging (LiDAR) scanner. Several vegetation indices, canopy temperature and LiDAR measured plant height were derived from the remote sensing data and their relation with ground measured parameters like salt treatment, stomatal conductance and actual plant height is analysed. The results show that widely used multispectral vegetation indices are not efficient in discriminating between salt affected and control quinoa plants. The hyperspectral Physiological Reflectance Index (PRI) performed best and showed a clear distinction between salt affected and treated plants. This distinction is also visible for LiDAR measured plant height, where salt treated plants were on average 10 cm shorter than control plants. Canopy temperature was significantly affected, though detection of this required an additional step in analysis – Normalised Difference Vegetation Index (NDVI) clustering. This step assured temperature comparison for equally vegetated pixels. Data combination of all three sensors in a Multiple Linear Regression model increased the prediction power and for the whole dataset R2 reached 0.46, with some subgroups reaching an R2 of 0.64. We conclude that UAV borne remote sensing is useful for measuring salt stress in plants and a combination of multiple measurement techniques is advised to increase the accuracy.

    Comparing Serial, and Choice Task Stated and Inferred Attribute Non-Attendance Methods in Food Choice Experiments
    Caputo, Vincenzina ; Loo, Ellen J. Van; Scarpa, Riccardo ; Nayga, Rodolfo M. ; Verbeke, Wim - \ 2018
    Journal of Agricultural Economics 69 (2018)1. - ISSN 0021-857X - p. 35 - 57.
    Attribute non-attendance - choice experiments - choice task stated attribute non-attendance - inferred attribute non-attendance - serial stated attribute non-attendance - sustainable food labels

    A number of choice experiment (CE) studies have shown that survey respondents employ heuristics such as attribute non-attendance (ANA) while evaluating food products. This paper addresses a set of related methodological questions using empirical consumer data from a CE on poultry meat with sustainability labels. First, it assesses whether there are differences in terms of marginal willingness to pay estimates between the two most common ways of collecting stated ANA (serial and choice task level). Second, it validates the self-reported ANA behaviour across both approaches. Third, it explores the concordance of stated methods with that of the inferred method. Results show that WTP estimates from serial-level data differ from those from choice task-level data. Also, self-reported measures on choice task ANA are found to be more congruent with model estimates than those for serial ANA, as well as with inferred ANA.

    Consumer valuation of quality rice attributes in a developing economy: Evidence from a choice experiment in Vietnam
    My, Nguyen H.D. ; Loo, Ellen J. Van; Rutsaert, Pieter ; Tuan, Tran Huu ; Verbeke, Wim - \ 2018
    British Food Journal 120 (2018)5. - ISSN 0007-070X - p. 1059 - 1072.
    Consumer - IPM - Organic - Rice - Sustainability - WTP

    Purpose: The purpose of this paper is to investigate consumers’ willingness to pay for quality rice attributes in urban areas in the South of Vietnam, including organic and integrated pest management (IPM) as sustainable production methods, and claim about health benefits and fair farmer prices. Design/methodology/approach: Cross-sectional data were collected in 2015 using a survey including a choice experiment (CE) (n=500). Generalized mixed logit models were estimated. Findings: Vietnamese consumers are willing to pay a premium of 82 percent for organic rice, and 45 percent for rice produced using IPM, compared to conventionally produced rice. They are also willing to pay a premium of 95 percent for rice claiming to be rich in vitamins and other nutrients, and 50 percent for rice that guarantees a fair price to rice farmers. Research limitations/implications: A hypothetical CE was employed. Future research using revealed preference methods is suggested. Originality/value: This study makes a significant contribution to the limited existing literature on consumers’ valuation of quality rice attributes in the context of developing countries such as Vietnam. The study shows that rice, that is, sustainably produced using organic or IPM methods provides a promising avenue for rice producers. This study highlights that there is an added value for rice with credence attributes in relation to sustainable production methods, health benefits, and fair farmer prices in a developing country.

    Using eye tracking to account for attribute non-attendance in choice experiments
    Loo, Ellen J. Van; Nayga, Rodolfo M. ; Campbell, Danny ; Seo, Han Seok ; Verbeke, Wim - \ 2018
    European Review of Agricultural Economics 45 (2018)3. - ISSN 0165-1587 - p. 333 - 365.
    Attribute non-attendance - Decision-making - Eye tracking - Food choice - Sustainability labelling

    This study uses eye-tracking measures to account for attribute non-attendance (ANA) in choice experiments. Using the case of sustainability labelling on coffee, we demonstrate various approaches to account for ANA based on the fixation count cut-offs, definitions for detecting ignored attributes, and methods for modelling ANA. Some of the sustainability attributes identified through eye-tracking measures as being ‘visually ignored’ were truly ignored, whereas in none of the tested approaches was price truly ignored. The adequacy of eye tracking as a visual ANA measure might thus depend on the type of attribute. Further, the study unveiled inconsistencies in identifying non-attenders using visual ANA and the coefficient of variation. Based on our results, we cannot conclude that eye tracking always adequately identifies ANA. However, we identified several major challenges that can assist in further optimising the use of eye tracking in the context of ANA.

    What is the value of sustainably-produced rice? Consumer evidence from experimental auctions in Vietnam
    My, Nguyen H.D. ; Demont, Matty ; Loo, Ellen J. Van; Guia, Annalyn de; Rutsaert, Pieter ; Tuan, Tran Huu ; Verbeke, Wim - \ 2018
    Food Policy 79 (2018). - ISSN 0306-9192 - p. 283 - 296.
    BDM auction - GlobalG.A.P. - Rice - Sustainability - VietGAP - Vietnam

    Little is known about the value of sustainably-produced rice and incentive mechanisms for the adoption of sustainable production standards throughout rice value chains in Southeast Asia. This study tests the feasibility of a market-based incentive mechanism by eliciting consumers’ willingness-to-pay (WTP) for rice produced and labeled under a national sustainable production standard in the South of Vietnam through experimental auctions. Domestic consumers are willing to pay a 9% price premium for certified sustainably-produced rice. This premium gradually increases up to 33% when incremental levels of information on certification and traceability are provided. Consumers willing to pay premiums for sustainably-produced rice are more health-conscious, have better knowledge of and greater trust in food quality certification for rice, and tend to be more environmentally conscious and to read food labels before purchasing. Findings suggest that sustainable production labels for rice should be accompanied by supplementary information on certification and traceability to increase consumers’ awareness and appreciation of sustainably-produced rice. Promoting certified sustainably-produced rice hence crucially hinges on strengthening consumers’ knowledge of and trust in food quality certification. Communication strategies are recommended to focus on the environmental and health benefits of sustainably-produced rice.

    On the Measurement of Consumer Preferences and Food Choice Behavior: The Relation Between Visual Attention and Choices
    Loo, Ellen J. Van; Grebitus, Carola ; Nayga, Rodolfo M. ; Verbeke, Wim ; Roosen, Jutta - \ 2018
    Applied Economic Perspectives and Policy 40 (2018)4. - ISSN 2040-5790 - p. 538 - 562.
    Choice - cues - eye tracking - information - labeling - visual attention

    When buying a product, consumers are confronted with a host of information presented to them. However, this information can only affect shoppers’ choices if they pay attention to it. Eye tracking can measure visual attention to information. Most recently, agricultural and food economics research has combined eye tracking and valuation methods to give insight into the relation between visual attention, preferences, and choices. We present an overview of the eye-tracking literature, and discuss theory and applications. Also, insights on how to measure visual attention and choice are provided. While eye tracking has its challenges, there are interesting future research avenues that can be explored by agricultural and food economists using eye tracking.

    Camelina Crambe And Insects
    Wubben, E.F.M. ; Blaauw, R. ; Loo, E.N. van; Togtema, K.A. - \ 2018
    Wageningen : Wageningen Food & Biobased Research
    biobased economy - innovations - crops - biomass - residual streams - insects - oils - camelina - crambe - agricultural wastes
    Microorganisms in bioflocs make unavailable phosphate, fixed in dietary phytate, available for Nile tilapia
    Verdegem, M.C.J. ; Hutting, Samara ; Loo, Joost van; Schrama, J.W. ; Verreth, J.A.J. - \ 2018
    - 2 p.
    Check title to add to marked list
    << previous | next >>

    Show 20 50 100 records per page

    Please log in to use this service. Login as Wageningen University & Research user or guest user in upper right hand corner of this page.