Staff Publications

Staff Publications

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    '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.

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    Supplying high-quality alternative prey in the litter increases control of an above-ground plant pest by a generalist predator
    Muñoz-Cárdenas, Karen ; Ersin, Firdevs ; Pijnakker, Juliette ; Houten, Yvonne van; Hoogerbrugge, Hans ; Leman, Ada ; Pappas, Maria L. ; Duarte, Marcus V.A. ; Messelink, Gerben J. ; Sabelis, Maurice W. ; Janssen, Arne - \ 2017
    Biological Control 105 (2017). - ISSN 1049-9644 - p. 19 - 26.
    Supplying predators with alternative food can have short-term positive effects on prey densities through predator satiation (functional response) and long-term negative effects through increases of predator populations (numerical response). In biological control, alternative food sources for predators are normally supplied on the crop plants; using the litter-inhabiting food web as a source of alternative food for plant-inhabiting predators has received less attention. We investigated the effect of supplying plant-inhabiting predatory mites with alternative prey (astigmatic mites) in the litter on pest control. Predator (Amblyseius swirskii) movement and population dynamics of the pest (western flower thrips) and predators were studied on rose plants in greenhouses. Predators commuted between the above-ground plant parts where they controlled thrips, and the litter, where they fed on alternative prey, although the latter were a superior diet. Predators controlled thrips better in the presence of the astigmatic mites than in their absence. We show that predatory mites can form a link between above-ground pests and the litter food web, and propose that adding alternative prey to the litter of ornamental greenhouses can result in higher predator densities and increased biological control.
    Inbreeding depression and purging in a haplodiplois: gender-related effects
    Tien, N.S.H. ; Sabelis, M.W. ; Egas, M. - \ 2015
    Heredity 114 (2015). - ISSN 0018-067X - p. 327 - 332.
    x-linked genes - female fecundity - load - populations - selection - genetics - mite - extinction
    Compared with diploid species, haplodiploids suffer less inbreeding depression because male haploidy imposes purifying selection on recessive deleterious alleles. However, alleles of genes only expressed in the diploid females are protected in heterozygous individuals. This leads to the prediction that haplodiploids suffer more from inbreeding effects on life-history traits controlled by genes with female-limited expression. To test this, we used a wild population of the haplodiploid mite Tetranychus urticae. First, negative effects of inbreeding were investigated by comparing maturation rate, juvenile survival, oviposition rate and longevity between lines created by three generations of either outbreeding or mother-son inbreeding. Second, purging through inbreeding was investigated by comparing the intensity of inbreeding depression between outbred families with known inbreeding/outbreeding mating histories. Negative effects of inbreeding and evidence for purging were found for the female trait oviposition rate, but not for juvenile survival and longevity. Both male and female maturation rate were negatively affected by inbreeding, most likely due to maternal effects because inbred offspring of outbred mothers was not affected. These results support the hypothesis that, in haplodiploids inbreeding effects and genetic variation due to deleterious recessive alleles may depend on gender.
    Duurzame bestrijding tulpengalmijt : onderzoek naar de effectiviteit van de roofmijt Neoseiulus paspalivorus tegen tulpengalmijt Aceria tulipae en onderzoek naar alternatieve voedselbronnen voor N. paspalivorus
    Kuik, A.J. van; Silva, F. da; Lesna, I. ; Sabelis, M. - \ 2014
    Lisse : Praktijkonderzoek Plant & Omgeving, Business Unit Bloembollen, Boomkwekerij & Fruit - 35
    tulpen - opslag - gewasbescherming - roofmijten - aceria tulipae - neoseiulus - massakweek - organismen ingezet bij biologische bestrijding - tulips - storage - plant protection - predatory mites - aceria tulipae - neoseiulus - mass rearing - biological control agents
    Tulpengalmijt vormt de grootste plaag in de bewaring van tulpen, is een risico voor verspreiding van TVX en kost de sector jaarlijks miljoenen euro’s. Huidige bestrijdingsmethodes werken in praktijk niet voldoende. Eerder onderzoek heeft aangetoond dat de roofmijt Neoseiulus paspalivorus tulpengalmijt in de bewaring goed in toom kan houden (project 14745). In een vervolgproef werd weer aangetoond dat de kleine roofmijt een goede bestrijder is van tulpengalmijt. Verder is er een stap gezet naar massakweek van de roofmijt door het vinden van alternatieve voedselbronnen. Met producenten van biologische bestrijders zijn contacten gelegd om de mogelijkheden voor commerciële massakweek te verkennen.
    Biological control of aphids in the presence of thrips and their enemies
    Messelink, G.J. ; Bloemhard, C.M.J. ; Sabelis, M.W. ; Janssen, A. - \ 2013
    BioControl 58 (2013)1. - ISSN 1386-6141 - p. 45 - 55.
    intraguild predation - generalist predators - alternative prey - apparent competition - suppression - biocontrol - biodiversity - communities - parasitoids - predictions
    Generalist predators are often used in biological control programs, although they can be detrimental for pest control through interference with other natural enemies. Here, we assess the effects of generalist natural enemies on the control of two major pest species in sweet pepper: the green peach aphid Myzus persicae (Sulzer) and the western flower thrips Frankliniella occidentalis (Pergande). In greenhouses, two commonly used specialist natural enemies of aphids, the parasitoid Aphidius colemani Viereck and the predatory midge Aphidoletes aphidimyza (Rondani), were released together with either Neoseiulus cucumeris Oudemans, a predator of thrips and a hyperpredator of A. aphidimyza, or Orius majusculus (Reuter), a predator of thrips and aphids and intraguild predator of both specialist natural enemies. The combined use of O. majusculus, predatory midges and parasitoids clearly enhanced the suppression of aphids and consequently decreased the number of honeydew-contaminated fruits. Although intraguild predation by O. majusculus on predatory midges and parasitoids will have affected control of aphids negatively, this was apparently offset by the consumption of aphids by O. majusculus. In contrast, the hyperpredator N. cucumeris does not prey upon aphids, but seemed to release aphids from control by consuming eggs of the midge. Both N. cucumeris and O. majusculus did not affect rates of aphid parasitism by A. colemani. Thrips were also controlled effectively by O. majusculus. A laboratory experiment showed that adult predatory bugs feed on thrips as well as aphids and have no clear preference. Thus, the presence of thrips probably promoted the establishment of the predatory bugs and thereby the control of aphids. Our study shows that intraguild predation, which is potentially negative for biological control, may be more than compensated by positive effects of generalist predators, such as the control of multiple pests, and the establishment of natural enemies prior to pest invasions. Future work on biological control should focus on the impact of species interactions in communities of herbivorous arthropods and their enemies.
    Prey temporarily escape from predation in the presence of a second prey species
    Maanen, R. van; Messelink, G.J. ; Holstein, R. van; Sabelis, M.W. ; Janssen, A. - \ 2012
    Ecological Entomology 37 (2012)6. - ISSN 0307-6946 - p. 529 - 535.
    mediated apparent competition - biological-control agents - western flower thrips - phytoseiid predators - tetranychus-urticae - amblyseius-swirskii - alternative prey - frankliniella-occidentalis - generalist predator - population-dynamics
    1. Indirect interactions between populations of different prey species mediated by a shared predator population are known to affect prey dynamics. 2. Depending on the temporal and spatial scale, these indirect interactions may result in positive (apparent mutualism), neutral or negative effects (apparent competition) of the prey on each other's densities. Although there is ample evidence for the latter, evidence for apparent mutualism is scarce. 3. The effectiveness of using one species of predator for biological control of more than one pest species depends on the occurrence of such positive or negative effects. 4. We used an experimental system consisting of the two prey species Western flower thrips (Franklineilla occidentalis Pergande) and greenhouse whitefly (Trialeurodes vaporariorum Westwood) and a shared predator, the phytoseiid mite Amblyseius swirskii Athias-Henriot. We released all three species on the same plant and studied their dynamics and distribution along rows of plants. 5. We expected that the more mobile prey species (thrips) would escape temporarily in the presence of the other prey species (whitefly) by dispersing from plants with the predator. The predator was expected to disperse slower in the presence of two prey species because of the higher availability of food. 6. Evidence was found for slower dispersal of predators and short-term escape of thrips from predation when whiteflies were present, thus confirming the occurrence of short-term apparent mutualism. 7. The apparent mutualism resulted in a cascade to the first trophic level: a higher proportion of fruits was damaged by thrips in the presence of whiteflies. 8. We conclude that apparent mutualism can be an important phenomenon in population dynamics, and can significantly affect biological control of pest species that share a natural enemy.
    Neoseiulus paspalivorus, een nieuwe bestrijder van tulpengalmijt?!
    Lommen, S.T.E. ; Lesna, I. ; Sabelis, M.W. ; Kuik, A.J. van; Silva, F. - \ 2012
    Lisse : Praktijkonderzoek Plant & Omgeving, Bollen en Bomen - 31
    aceria tulipae - gewasbescherming - plagenbestrijding - bestrijdingsmethoden - landbouwkundig onderzoek - proeven - roofmijten - neoseiulus - tulpen - opslag - organismen ingezet bij biologische bestrijding - aceria tulipae - plant protection - pest control - control methods - agricultural research - trials - predatory mites - neoseiulus - tulips - storage - biological control agents
    Tulpengalmijt vormt de grootste plaag in de bewaring van tulpen, is een risico voor verspreiding van TVX en kost de sector jaarlijks miljoenen euro’s. Huidige bestrijdingsmethodes werken in praktijk niet bevredigend en de toekomst van chemische middelen is onduidelijk. Reden voor PPO en de Universiteit van Amsterdam om samen onderzoek te doen naar alternatieve bestrijdingsmethode met roofmijten. De eerste proeven tonen aan dat de Braziliaanse rover Neoseiulus paspalivorus tulpengalmijt in de bewaring in toom kan houden en zichzelf goed kan handhaven. Hij presteert daarbij vele malen beter dan de eerder onderzochte Neoseiulus cucumeris. Vertegenwoordigers uit de praktijk zien kansen voor deze nieuwe roofmijt maar hebben nog veel vragen.
    Laboratory tests for controlling poultry red mites (Dermanyssus gallinae) with predatory mites in small ‘laying hen’ cages
    Lesna, I. ; Sabelis, M.W. ; Niekerk, T.G.C.M. van; Komdeur, J. - \ 2012
    Experimental and Applied Acarology 58 (2012)4. - ISSN 0168-8162 - p. 371 - 383.
    biological-control - acari - susceptibility - ectoparasites - mesostigmata - management - stand
    To assess their potential to control poultry red mites (Dermanyssus gallinae), we tested selected predaceous mites (Androlaelaps casalis and Stratiolaelaps scimitus) that occur naturally in wild bird nests or sometimes spontaneously invade poultry houses. This was done under laboratory conditions in cages, each with 2–3 laying hens, initially 300 poultry red mites and later the release of 1,000 predators. These small-scale tests were designed to prevent mite escape from the cages and they were carried out in three replicates at each of three temperature regimes: 26, 30 (constant day and night) and 33–25 °C (day-night cycle). After 6 weeks total population sizes of poultry red mites and predatory mites were assessed. For the temperature regimes of 26 and 33/25 °C S. scimitus reduced the poultry red mite population relative to the control experiments by a factor 3 and 30, respectively, and A. casalis by a factor of 18 and 55, respectively. At 30 °C the predators had less effect on red mites, with a reduction of 1.3-fold for S. scimitus and 5.6-fold for A. casalis. This possibly reflected hen manure condition or an effect of other invertebrates in the hen feed. Poultry red mite control was not negatively affected by temperatures as high as 33 °C and was always better in trials with A. casalis than in those with S. scimitus. In none of the experiments predators managed to eradicate the population of poultry red mites. This may be due to a prey refuge effect since most predatory mites were found in and around the manure tray at the bottom of the cage, whereas most poultry red mites were found higher up in the cage (i.e. on the walls, the cover, the perch, the nest box and the food box). The efficacy of applying predatory mites in the poultry industry may be promoted by reducing this refuge effect, boosting predatory mite populations using alternative prey and prolonged predator release devices. Biocontrol success, however, will strongly depend on how the poultry is housed in practice (free range, cage or aviary systems) and on which chemicals are applied to disinfect poultry houses and to control other pests
    Whether ideal free or not, predatory mites distribute so as to maximize reproduction
    Hammen, T. van der; Montserrat, M. ; Sabelis, M.W. ; Roos, A.M. ; Janssen, A. - \ 2012
    Oecologia 169 (2012)1. - ISSN 0029-8549 - p. 95 - 104.
    free distribution models - unequal competitors - egg predation - interference - density - prey - phytoseiidae - oviposition - tests
    Ideal free distribution (IFD) models predict that animals distribute themselves such that no individual can increase its fitness by moving to another patch. Many empirical tests assume that the interference among animals is independent of density and do not quantify the effects of density on fitness traits. Using two species of predatory mites, we measured oviposition as a function of conspecific density. Subsequently, we used these functions to calculate expected distributions on two connected patches. We performed an experimental test of the distributions of mites on two such connected patches, among which one had a food accessibility rate that was twice as high as on the other. For one of the two species, Iphiseius degenerans, the distribution matched the expected distribution. The distribution also coincided with the ratio of food accessibility. The other species, Neoseiulus cucumeris, distributed itself differently than expected. However, the oviposition rates of both species did not differ significantly from the expected oviposition rates based on experiments on single patches. This suggests that the oviposition rate of N. cucumeris was not negatively affected by the observed distribution, despite the fact that N. cucumeris did not match the predicted distributions. Thus, the distribution of one mite species, I. degenerans, was in agreement with IFD theory, whereas for the other mite species, N. cucumeris, unknown factors may have influenced the distribution of the mites. We conclude that density-dependent fitness traits provide essential information for explaining animal distributions
    Generalist predators, food web complexities and biological pest control in greenhouse crops
    Messelink, G.J. - \ 2012
    University of Amsterdam (UvA). Promotor(en): M.W. Sabelis, co-promotor(en): A.R.M. Janssen. - Amsterdam : Universiteit van Amsterdam - ISBN 9789491407048 - 148
    biologische bestrijding - predatoren van schadelijke insecten - glastuinbouw - voedselwebben - glasgroenten - systeembenadering - kasproeven - biological control - predators of insect pests - greenhouse horticulture - food webs - greenhouse vegetables - systems approach - greenhouse experiments
    Biologische bestrijding van plagen in kassen was lange tijd voornamelijk gericht op specialistische natuurlijke vijanden die sterk zijn aangepast aan hun prooi. Gerben Messelink onderzocht de rol van generalistische predatoren bij de bestrijding van meerdere plagen in de teelt van vruchtgroenten in kassen. Uit zijn resultaten blijkt dat spintmijten en witte vliegen - twee wereldwijde plagen - op een komkommergewas veel beter worden bestreden met generalistische roofmijten wanneer er ook tripsen (een ander belangrijk plaaginsect) aanwezig waren. Dit komt vooral doordat de roofmijten zich op een dieet van verschillende prooien sneller ontwikkelen. Hierdoor worden er snel hoge predatordichtheden bereikt. Messelink vond een vergelijkbaar mechanisme bij de bestrijding van plagen in paprika: roofwantsen gaven een zeer goede bestrijding van bladluis in de aanwezigheid van tripsen. Messelink verwacht dat generalistische predatoren in toenemende mate gebruikt zullen worden voor biologische plaagbestrijding in kassen, omdat de predatoren profiteren van een gemengd dieet van verschillende plagen en de plaagbestrijding op die manier makkelijker maakt.
    Generalist Predators, Food Web Complexities and Biological Pest Control in Greenhouse Crops
    Messelink, G.J. ; Sabelis, M.W. ; Janssen, A. - \ 2012
    In: Integrated Pest Management and Pest Control - Current and Future Tactics / Larramendy, M.L., Soloneski, S., InTech - ISBN 9789535100508 - p. 191 - 214.
    Studying culture and symbolism in organizations
    Ybema, S. ; Yanow, D. - \ 2011
    In: Organizational culture / Ybema, S., Yanow, D., Sabelis, I., Cheltenham : Edgar Elgar Publishing - ISBN 9781849800471 - p. xi - xxxii.
    Organizational Culture : Two volume set
    Ybema, S. ; Yanow, D. ; Sabelis, I. - \ 2011
    Cheltenham : Edgar Elgar Publishing - ISBN 9781849800471 - 192 p.
    Colonization of eucalyptus in Brazil by an insect herbivore and its enemies: Herbivores find enemy-free space on a novel host plant
    Grosman, A.H. - \ 2011
    University of Amsterdam. Promotor(en): M.W. Sabelis; S.B.J. Menken. - - 143 p.
    Hyperpredation by generalist predatory mites disrupts biological control of aphids by the aphidophagous gall midge Aphidoletes aphidimyza
    Messelink, G.J. ; Bloemhard, C.M.J. ; Cortes, J.A. ; Sabelis, M.W. ; Jansen, A. - \ 2011
    Biological Control 57 (2011)3. - ISSN 1049-9644 - p. 246 - 252.
    intraguild predation - phytoseiid predators - neoseiulus-cucumeris - amblyseius-swirskii - bemisia-tabaci - acari phytoseiidae - prey communities - alternative food - myzus-persicae - control agents
    Biological control of different species of pest with various species of generalist predators can potentially disrupt the control of pests through predator-predator interactions. We evaluate the impact of three species of generalist predatory mites on the biological control of green peach aphids, Myzus persicae (Sulzer) with the aphidophagous gall midge Aphidoletes aphidimyza (Rondani). The predatory mites tested were Neoseiulus cucumeris (Oudemans), Iphiseius degenerans (Berlese) and Amblyseius swirskii Athias–Henriot, which are all commonly used for pest control in greenhouse sweet pepper. All three species of predatory mites were found to feed on eggs of A. aphidimyza, even in the presence of abundant sweet pepper pollen, an alternative food source for the predatory mites. In a greenhouse experiment on sweet pepper, all three predators significantly reduced population densities of A. aphidimyza, but aphid densities only increased significantly in the presence of A. swirskii when compared to the treatment with A. aphidimyza only. This stronger effect of A. swirskii can be explained by the higher population densities that this predator reached on sweet pepper plants compared to the other two predator species. An additional experiment showed that female predatory midges do not avoid oviposition sites with the predator A. swirskii. On the contrary, they even deposited more eggs on plants with predatory mites than on plants without. Hence, this study shows that disruption of aphid control by predatory mites is a realistic scenario in sweet pepper, and needs to be considered when optimizing biological control strategies.
    Dermanyssus gallinae in Dutch poultry farms: Result of a questionaire on severity, control treatments, cleaning, and biosecurity
    Mul, M.F. ; Niekerk, T.G.C.M. van; Reuvekamp, B.F.J. ; Emous, R.A. van - \ 2010
    In: Trends in Acarology: Proceedings of the 12th International Congress / Sabelis, M.W., Bruin, J., Springer - ISBN 9789048198368 - p. 513 - 516.
    In 2005 a questionnaire has been sent to 1,390 Dutch poultry farmers to investigate the severity of the poultry red mite (PRM) as a pest problem in The Netherlands. The response rate amounted to 31%. As the questions were not independent of each other, four clusters of questions were formed, based on two observed, discrete variables: (1) directly visible PRM infestation, and (2) indirect signs of the presence of PRM. Respondents were distributed over the most common housing systems in The Netherlands and reflected the Dutch situation with regards to housing of laying hens quite well. More than 80% of the poultry farmers reported infestations of PRM. Chicken flocks without PRM problems were significantly younger than flocks where (signs of) PRM infestation were observed. Where poultry was housed in battery cages, more farmers reported problems with PRM infestations, they tend to apply the first control treatment earlier, and repeat it more often than farmers with poultry in other housing systems. When PRM or signs of PRM were reported, farmers more often applied a combination of control treatments. The mean costs paid for control treatments and the costs incurred in terms of production losses were estimated to be € 0.43 per hen in an average flock. Given that there are 300 million layer hens in Dutch poultry houses and that ca. 85% of the flocks are PRMinfested, the overall annual cost to the national poultry industry is estimated at € 11 million. Since the answers to the questionnaire revealed a significant underuse of several measures that could prevent PRM infestation, there is room for improvement by more stringent management
    Framing Conflict in Participatory Forest Management: The Case of Agoua Forest Restoration in Benin
    Aarts, M.N.C. ; Idrissou Aboubacary, L. ; Paassen, A. van; Leeuwis, C. - \ 2010
    In: Organizational Discourse: Crises, Corruption, Character and Change. Proceedings of the 9th int. conference, Amsterdam, July 14-16. - London : University of London - p. 18 - 21.
    Pest species diversity enhances control of spider mites and whiteflies by a generalist phytoseiid predator
    Messelink, G.J. ; Maanen, R. van; Holstein-Saj, R. van; Sabelis, M.W. ; Janssen, A. - \ 2010
    BioControl 55 (2010)3. - ISSN 1386-6141 - p. 387 - 398.
    western flower thrips - mediated apparent competition - biological-control agents - intraguild predation - plant-resistance - alternative prey - carabid beetles - food - diet - biodiversity
    To test the hypothesis that pest species diversity enhances biological pest control with generalist predators, we studied the dynamics of three major pest species on greenhouse cucumber: Western flower thrips, Frankliniella occidentalis (Pergande), greenhouse whitefly, Trialeurodes vaporariorum (Westwood), and two-spotted spider mites, Tetranychus urticae Koch in combination with the predator species Amblyseius swirskii Athias-Henriot. When spider mites infested plants prior to predator release, predatory mites were not capable of controlling spider mite populations in the absence of other pest species. A laboratory experiment showed that predators were hindered by the webbing of spider mites. In a greenhouse experiment, spider mite leaf damage was lower in the presence of thrips and predators than in the presence of whiteflies and predators, but damage was lowest in the presence of thrips, whiteflies and predators. Whitefly control was also improved in the presence of thrips. The lower levels of spider mite leaf damage probably resulted from (1) a strong numerical response of the predator (up to 50 times higher densities) when a second and third pest species were present in addition to spider mites, and (2) from A. swirskii attacking mobile spider mite stages outside or near the edges of the spider mite webbing. Interactions of spider mites with thrips and whiteflies might also result in suppression of spider mites. However, when predators were released prior to spider mite infestations in the absence of other pest species, but with pollen as food for the predators, we found increased suppression of spider mites with increased numbers of predators released, confirming the role of predators in spider mite control. Thus, our study provides evidence that diversity of pest species can enhance biological control through increased predator densities
    Spatial distribution of predator and pests in greenhouses
    Maanen, R. van; Messelink, G.J. ; Holstein, R. van; Janssen, A. ; Sabelis, M.W. - \ 2009
    We studied the distribution of the predator, Amblyseius swirskii and the herbivores western flower thrips (Frankliniella occidentalis) and the greenhouse whitefly (Trialeurodes vaporariorum) in a glasshouse experiment. In 5 compartments thrips adults and predatory mites were released on every second plant of a row (Treatment A). In two compartments also whitefly adults were released (Treatment B). The first three weeks we monitored the distribution of mites weekly and found a significant difference in dispersal of mites between treatments. In greenhouse compartments where only one pest species was present, mites dispersed faster compared to compartments where two pest species were present. The numbers of predatory mites and pests of the third, sixth and ninth plant of each row were assessed 4, 6, 8 and 10 weeks after introducing the predatory mites. There was no effect of the presence of whiteflies on distribution of thrips and mites.
    Gewasbescherming van opkomst tot oogst in de gesloten productie
    Janssen, A. ; Maanen, R. van; Messelink, G.J. ; Sabelis, M.W. - \ 2008
    Gewasbescherming 39 (2008)Suppl.. - ISSN 0166-6495 - p. 17 - 17.
    biologische bestrijding - kassen - voedselwebben - voedselketens - interacties - analytische methoden - risicoschatting - glastuinbouw - agro-ecosystemen - plant-herbivoor relaties - insect-plant relaties - biological control - greenhouses - food webs - food chains - interactions - analytical methods - risk assessment - greenhouse horticulture - agroecosystems - plant-herbivore interactions - insect plant relations
    Development of an extraction method for roots of Thuja occidentalis and a bio-assay to test its attractiveness for Heterorhabditis megidis
    Prins, M.W. ; Tol, R.W.H.M. van; Voogt, P. de; Sabelis, M.W. - \ 2006
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