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.

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Keuzedeel Landbouwhuisdieren (MBO)
Ruis, M.A.W. ; Vorderman, Evert ; Dijk, Nienke van; Fokkema, R. ; Visser, Annewies ; Hessel, Huub ; Hoorweg, Fleur ; Groffen, H. ; Korsten, C. ; Goot, L. van der; Hoop, O. de - \ 2019
Wageningen : Groen Kennisnet
Data from: Agricultural pastures challenge the attractiveness of natural saltmarsh for a migratory goose
Dokter, A.M. ; Fokkema, Wimke ; Ebbinge, B.S. ; Olff, H. ; Jeugd, Henk P. van der; Nolet, B.A. - \ 2018
pastures - saltmarsh - brent geese - human-goose conflict - accelerometer - GPS tracking - intertidal - habitat switching - migration - fuelling
Broad-scale land conversions and fertilizer use have dramatically altered the available staging area for herbivorous long-distance migrants. Instead of natural land, these birds rely increasingly on pastures for migratory fuelling and stopover, often conflicting with farming practices. To be able to predict and manage birds’ future habitat use, the relative advantages and disadvantages of natural (e.g. saltmarsh, intertidal) versus anthropogenic staging sites for foraging need to be understood. 2. We compared the migratory staging of brent geese on saltmarsh and pasture sites in spring. Food quality (nitrogen and fibre content), intra-specific antagonistic behaviour, and body weight were quantified at nearby sites in simultaneous seasons. Individuals were tracked with high-resolution GPS and accelerometers to compare timing of migration and time-budgets during fuelling. 3. On pastures, birds rested more and experienced higher ingestion rates, similar or superior food quality and reduced antagonistic interactions than on saltmarsh. 4. Brent geese using fertilized grasslands advanced their fuelling and migration schedules compared to those using saltmarsh. Pasture birds reached heavy weights earlier, departed sooner, and arrived in the Arctic earlier. 5. Intertidal mudflats were frequently visited by saltmarsh birds during the day, and available food there (algae, some seagrass) was of higher quality than terrestrial resources. Availability of intertidal resources was an important factor balancing the otherwise more favourable conditions on pastures relative to saltmarsh. 6. Policy implications: Disadvantages of longer foraging effort, more antagonistic interactions and delayed fuelling schedules on traditional saltmarshes may cause a trend of geese exchanging this traditional niche in favour of pastures, especially in a warming climate that requires advancement of migratory schedules. However, the high quality of intertidal forage allows it to complement terrestrial foraging, potentially removing the incentive for habitat switches to pastures. The relatively high quality of green algae and seagrass, and birds’ remarkable preference for these resources when available, provides a key for managers to create landscapes that can sustain this specialist’s intertidal lifestyle. To keep natural habitats attractive to staging geese with the purpose to prevent conflicts with farming practices, management actions should focus on conservation and restoration of saltmarsh and especially intertidal habitat.
Data from: Body stores persist as fitness correlate in a long-distance migrant released from food constraints
Dokter, Adriaan M. ; Fokkema, Wimke ; Bekker, Steven K. ; Bouten, Willem ; Ebbinge, B.S. ; Muskens, G.J.D.M. ; Olff, H. ; Jeugd, Henk P. van der; Nolet, B.A. - \ 2018
arctic waterfowl - cultivated grassland - recruitment - GPS tracking - migratory fueling - carry-over effects
Long-distance migratory birds rely on acquisition of body reserves to fuel their migration and reproduction. Breeding success depends on the amount of body reserve acquired prior to migration, which is thought to increase with access to food at the fuelling site. Here we studied how food abundance during fuelling affected time budgets and reproductive success. In a regime of plenty, we expected that (1) limitations on food harvesting would become lifted, allowing birds to frequently idle, and (2) that birds would reach sufficient fuel loads, such that departure weight would no longer affect reproductive success. Our study system comprised brent geese (Branta b. bernicla) staging on high-quality agricultural pastures. Fuelling conditions were assessed by a combination of high-resolution GPS-tracking, acceleration-based behavioural classification, thermoregulation modelling, and measurements of food digestibility and excretion rates. Mark-resighting analysis was used to test for correlations between departure weight and offspring recruitment. Our results confirm that birds loafed extensively, actively postponed fuelling in early spring, and took frequent digestion pauses, suggesting that traditional time constraints on harvest and fuelling rates are absent on modern-day fertilized grasslands. Nonetheless, departure weight remained correlated with recruitment success. The persistence of this correlation after a prolonged stopover with access to abundant high-quality food, suggests that between-individual differences in departure condition are not so much enforced by food quality and availability during stopover, but reflect individual quality and longer-lived life-history traits, such as health status and digestive capacity, which may be developed before the fuelling period.
Agricultural pastures challenge the attractiveness of natural saltmarsh for a migratory goose
Dokter, Adriaan M. ; Fokkema, Wimke ; Ebbinge, Barwolt S. ; Olff, Han ; Jeugd, Henk P. van der; Nolet, Bart A. - \ 2018
Journal of Applied Ecology 55 (2018)6. - ISSN 0021-8901 - p. 2707 - 2718.
accelerometer - brent geese - GPS tracking - habitat switching - human–goose conflict - migration - pastures - saltmarsh

Broad-scale land conversions and fertilizer use have dramatically altered the available staging area for herbivorous long-distance migrants. Instead of natural land, these birds rely increasingly on pastures for migratory fuelling and stopover, often conflicting with farming practices. To predict and manage birds’ future habitat use, the relative advantages and disadvantages of natural (e.g. saltmarsh, intertidal) versus anthropogenic staging sites for foraging need to be understood. We compared the migratory staging of brent geese on saltmarsh and pasture sites in spring. Food quality (nitrogen and fibre content), antagonistic behaviour, and body weight were quantified at nearby sites in simultaneous seasons. Individuals were tracked with high-resolution GPS and accelerometers to compare timing of migration and time budgets during fuelling. On pastures, birds rested more and experienced higher ingestion rates, similar or superior food quality and reduced antagonistic interactions than on saltmarsh. Brent geese using fertilized grasslands advanced their fuelling and migration schedules compared to those using saltmarsh. Pasture birds reached heavy weights earlier, departed sooner, and arrived in the Arctic earlier. Intertidal mudflats were frequently visited by saltmarsh birds during the day, and available food there (algae, some seagrass) was of higher quality than terrestrial resources. Availability of intertidal resources was an important factor balancing the otherwise more favourable conditions on pastures relative to saltmarsh. Synthesis and applications. Disadvantages of longer foraging effort, more antagonistic interactions and delayed fuelling schedules on traditional saltmarshes may cause geese to exchange this traditional niche in favour of pastures, especially in a warming climate that requires advancement of migratory schedules. However, due to its high quality, intertidal forage can complement terrestrial foraging, potentially removing the incentive for habitat switches to pastures. The relatively high quality of green algae and seagrass, and birds’ remarkable preference for these resources when available, provides a key for managers to create landscapes that can sustain this specialist’s intertidal lifestyle. To keep natural habitats attractive to staging geese with the purpose of preventing conflicts with farming practices, management actions should focus on conservation and restoration of saltmarsh and especially intertidal habitat.

Body stores persist as fitness correlate in a long-distance migrant released from food constraints
Dokter, Adriaan M. ; Fokkema, Wimke ; Bekker, Steven K. ; Bouten, Willem ; Ebbinge, Barwolt S. ; Müskens, Gerard ; Olff, Han ; Jeugd, Henk P. van der; Nolet, Bart A. - \ 2018
Behavioral Ecology 29 (2018)5. - ISSN 1045-2249 - p. 1157 - 1166.
arctic waterfowl - carry-over effects - cultivated grassland - GPS tracking - migratory fueling - recruitment

Long-distance migratory birds rely on the acquisition of body stores to fuel their migration and reproduction. Breeding success depends on the amount of body stores acquired prior to migration, which is thought to increase with access to food at the fueling site. Here, we studied how food abundance during fueling affected time budgets and reproductive success. In a regime of plenty, we expected that 1) limitations on food harvesting would become lifted, allowing birds to frequently idle, and 2) birds would reach sufficient fuel loads, such that departure weight would no longer affect reproductive success. Our study system comprised brent geese (Branta b. bernicla) staging on high-quality agricultural pastures. Fueling conditions were assessed by a combination of high-resolution GPS tracking, acceleration-based behavioral classification, thermoregulation modeling, and measurements of food digestibility and excretion rates. Mark-resighting analysis was used to test for correlations between departure weight and offspring recruitment. Our results confirm that birds loafed extensively, actively postponed fueling in early spring, and took frequent digestion pauses, suggesting that traditional time constraints on harvest and fueling rates are absent on modern-day fertilized grasslands. Nonetheless, departure weight remained correlated with recruitment success. The persistence of this correlation after a prolonged stopover with access to abundant high-quality food, suggests that between-individual differences in departure condition are not so much enforced by food quality and availability during stopover, but reflect individual quality and longer-lived life-history traits, such as health status and digestive capacity, which may be developed before the fueling period.

Suppressiveness of Potato against Dickeya solani
Wolf, J.M. van der; Coipan, E.C. ; Kastelein, P. ; Krijger, M.C. ; Tom, Jolanda ; Riksen, Natasja ; Nijhuis, E.H. ; Warris, S. ; Fokkema, Jenny - \ 2017
In: Euphresco III Dickeya / Pectobacterium workshop. - - p. 8 - 8.
Plan van Aanpak voor MBO 'training en opleiding' rond Smart Dairy Farming : onderdeel van BOGO project 'Sensoren in SDF 1.0: lessen voor validatie en informatievoorziening'
Lokhorst, C. ; Fokkema, R. - \ 2015
Livestock Research Wageningen UR (Livestock Research rapport 934) - 14 p.
melkveehouderij - gegevens verzamelen - gegevensanalyse - sensors - bedrijfsvoering - opleiding melkveehouderij - beroepsopleiding - onderwijsprogramma's - dairy farming - data collection - data analysis - management - dairy education - vocational training - education programmes
Versterken van de positie van de school in de regio
Beers, P.J. ; Sol, A.J. ; Beckhoven, K. van; Essing, D. ; Kupper, F. ; Meij, M. van der; Rooze, R. ; Clasquin, A. ; Pillen, T. ; Mulder, E. ; Waggelink, W. ; Nawijn, A. ; Fokkema, R. - \ 2013
[Wageningen] : Wageningen University - 54
regioleren - onderwijsinstellingen - publiek-private samenwerking - netwerken (activiteit) - regio - kennisoverdracht - onderwijsmethoden - onderwijsvernieuwing - Nederland - regional atelier - educational institutions - public-private cooperation - networking - regions - knowledge transfer - teaching methods - educational innovation - Netherlands
Samen met studenten werken aan een betere toekomst voor de regio. Dat is regioleren. Ondernemers, overheden en maatschappelijke organisaties bepalen de agenda en werken samen met onderwijs en onderzoek aan oplossingen. Waar liggen de uitdagingen? Voor de instellingen is het een belangrijke uitdaging om aansluiting te vinden bij de regio. Hoe verander je van een onderwijsinstelling in een regionaal kenniscentrum? Hoe wordt je een volwaardige partner in een kenniswerkplaats? Een tweede belangrijke uitdaging ligt in de koppeling van het leren in de regio aan de lerende regio. In het programma Regionale Transitie is deze taak bij de kenniswerkplaatsen gelegd. De kenniswerkplaats is gebaseerd op een gezamenlijke regionale kennisagenda van overheid, ondernemers, maatschappelijke organisaties, onderwijs en onderzoek.
Feasilbility of phytoextraction to remediate cadmium and zinc contaminated soils
Koopmans, G.F. ; Romkens, P.F.A.M. ; Fokkema, M.J. ; Song, J. ; Luo, Y.M. ; Japenga, J. ; Zhao, F.J. - \ 2008
Environmental Pollution 156 (2008)3. - ISSN 0269-7491 - p. 905 - 914.
hyperaccumulator thlaspi-caerulescens - metal-accumulating plants - polluted soils - heavy-metals - sandy soil - zn - cd - phytoremediation - rhizosphere - field
A Cd and Zn contaminated soil was mixed and equilibrated with an uncontaminated, but otherwise similar soil to establish a gradient in soil contamination levels. Growth of Thlaspi caerulescens (Ganges ecotype) significantly decreased the metal concentrations in soil solution. Plant uptake of Cd and Zn exceeded the decrease of the soluble metal concentrations by several orders of magnitude. Hence, desorption of metals must have occurred to maintain the soil solution concentrations. A coupled regression model was developed to describe the transfer of metals from soil to solution and plant shoots. This model was applied to estimate the phytoextraction duration required to decrease the soil Cd concentration from 10 to 0.5 mg kg¿1. A biomass production of 1 and 5 t dm ha¿1 yr¿1 yields a duration of 42 and 11 yr, respectively. Successful phytoextraction operations based on T. caerulescens require an increased biomass production.
Feasibility of phytoextraction to remediate cadmium and zinc contaminated soils
Koopmans, G.F. ; Romkens, P.F.A.M. ; Fokkema, M.J. ; Song, J. ; Luo, Y. ; Japenga, J. ; Zhao, F.J. - \ 2008
In: The 3rd International Conference on Soil Pollution and Remediation, 18 - 21 October, 2008, Nanjing, China. - Nanjing : - p. 138 - 140.
A Cd and Zn contaminated soil was mixed and equilibrated with an uncontaminated, but otherwise similar soil to establish a gradient in soil contamination levels. Growth of Thlaspi caerulescens (Ganges ecotype) significantly decreased the metal concentrations in soil solution. Plant uptake of Cd and Zn exceeded the decrease of the soluble metal concentrations by several orders of magnitude. Hence, desorption of metals must have occurred to maintain the soil solution concentrations. A coupled regression model was developed to describe the transfer of metals from soil to solution and plant shoots. This model was applied to estimate the phytoextraction duration required to decrease the soil Cd concentration from 10 to 0.5mgkg(-1). A biomass production of 1 and 5tdmha(-1)yr(-1) yields a duration of 42 and 11yr, respectively. Successful phytoextraction operations based on T. caerulescens require an increased biomass production.
Inventarisatie en preventie van de belangrijkste bladvlekkenziekten in tarwe veroorzaakt door Pyrenophora tritici-repentis (DTR) en Septoria tritici: verslag over deel 2
Köhl, J. ; Kema, G.H.J. ; Fokkema, N.J. ; Goosseen-van de Geijn, H.M. ; Kastelein, P. ; Verstappen, E.C.P. - \ 2003
Wageningen : Plant Research International (Rapport / Plant Research International 43) - 98
pyrenophora tritici-repentis - septoria - triticum aestivum - tarwe - plantenziekten - bladvlekkenziekte - ziektepreventie - ziektedistributie - nederland - wheat - plant diseases - leaf spotting - disease prevention - disease distribution - netherlands
De gele bladvlekkenziekte (DTR) is in 1999 en 2000 respectievelijk op 75% en 25% van de geïnventariseerde percelen aangetroffen. De aantasting was gering; toch wijzen de ernstige aantastingen die op enkele percelen zijn aangetroffen op een potentieel gevaar. Het onderzoek heeft aangetoond dat het risico van een zware DTR-aantasting, naast ruime vruchtwisseling, sterk vermindert door intensieve grondbewerking waardoor de eerste infecties door ascosporen van besmette tarwestoppels onmogelijk worden
Joint toxicity of copper and zinc to a terrestrial nematode community in an acid sandy soil
Korthals, G.W. ; Bongers, M. ; Fokkema, A. ; Dueck, T.A. ; Lexmond, T.M. - \ 2000
Ecotoxicology 9 (2000). - ISSN 0963-9292 - p. 219 - 228.
Heavy metal toxicity to an indigenous nematode community was examined following the addition of Cu and Zn, alone or in combination, to agricultural soil. The dissolved Cu or Zn concentrations measured after equilibrating soil samples with a 0.01 M solution of CaCl2 showed that the metal concentrations found in soils with combined metal additions were not significantly different from those with single metal additions. After an exposure period of six months, many nematode community parameters and individual nematode taxa were significantly affected by increasing concentrations of Cu and Zn up to 200 mg kg-1. Some nematode taxa, such as Thonus, Alaimus and Aporcelaimellus were very sensitive and disappeared at Cu and Zn concentrations exceeding 50 mg kg-1. For several nematode community parameters and nematode taxa, EC50 values for single metal exposures were used to calculate TU50 values for the joint toxicity of Cu and Zn. Based on these calculations, it is concluded that the effects of a combined exposure to Cu and Zn were additive or less than additive. Before this conclusion can be generalised, however, more data are needed on other types of soil, other pH values and other combinations of pollutants.
Long-term biosanitation by application of Coniothyrium minitans on Sclerotinia sclerotiorum--infected crops
Gerlagh, M. ; Goossen-van de Geijn, H.M. ; Fokkema, N.J. ; Vereijken, P.F.G. - \ 1999
Phytopathology 89 (1999)2. - ISSN 0031-949X - p. 141 - 147.
The effect of the fungal mycoparasite Coniothyrium minitans applied as a spray to crops infected with Sclerotinia sclerotiorum (causal agent of white mold) on contamination of soil with S. sclerotiorum sclerotia was studied in a 5-year field experiment. Sclerotial survival also was monitored during two subsequent years, when the field was returned to commercial agriculture. In a randomized block design, factorial combinations of four crops and three treatments were repeated 10 times. Potato (Solanum tuberosum), bean (Phaseolus vulgaris), carrot (Daucus carota), and chicory (Cichorium intybus), which are all susceptible to S. sclerotiorum, were grown in rotation. Plots were treated with C. minitans or Trichoderma spp. or were nontreated (control). Crops were rotated in each plot, but treatments were applied to the same plot every year. After 3 years during which it showed no effect on sclerotial survival, the Trichoderma spp. treatment was replaced by a single spray with C. minitans during the fourth and fifth years of the trial. The effect of treatments was monitored in subsequent seasons by counting apothecia as a measure of surviving S. sclerotiorum sclerotia and scoring disease incidence. Trichoderma spp. did not suppress S. sclerotiorum, but C. minitans infected at least 90% of S. sclerotiorum sclerotia on treated crops by the end of the each season. C. minitans lowered the number of apothecia compared with the other treatments during the second year after the bean crop. C. minitans reduced the number of apothecia by ~90% when compared with the control and Trichoderma spp. treatments and reduced disease incidence in the bean crop by 50% during the fifth year of the trial, resulting in a slightly higher yield. In 1993, but not 1994, a single spray with C. minitans was nearly as effective at reducing apothecia as three sprays (monitored in 1995). The final population size of sclerotia in soil at the end of the 7-year period was lower in all C. minitans plots than at the beginning of the trial, even in plots where two highly susceptible bean crops were grown during the period. The results indicate that the mycoparasite C. minitans has the potential to keep contamination of soil with sclerotia low in crop rotations with a high number of crops susceptible to S. sclerotiorum.
Biological control of necrotrophic foliar fungal pathogens
Köhl, J. ; Fokkema, N.J. - \ 1998
In: Plant-Microbe Interactions and Biological control / Boland, G.J., Kuykendall, L.V., New York : Marcel Dekker - p. 49 - 88.
Biological control of Botrytis cinerea by suppression of sporulation
Köhl, J. ; Fokkema, N.J. - \ 1998
In: Proceedings of the 1998 Brighton Conference Pests and Diseases - p. 681 - 686.
Rhizoctonia disease of tulip : characterization and dynamics of the pathogens
Schneider, J.H.M. - \ 1998
Agricultural University. Promotor(en): J.C. Zadoks; N.J. Fokkema. - S.l. : Schneider - ISBN 9789054858522 - 173
plantenziekteverwekkende schimmels - deuteromycotina - bloembollen - plantenziektekunde - plantenfysiologie - tulipa - tulpen - rhizoctonia - plantenziekten - moniliaceae - tulips - plant pathogenic fungi - ornamental bulbs - plant pathology - plant physiology - plant diseases
<p>Rhizoctonia disease causes severe losses during the production cycle of tulip. The complex nature of the disease requires a precise characterization of the causal pathogens. Typical bare patches are caused by R. solani AG 2-t. Bulb rot symptoms are, apart from AG 2-t isolates, caused by R. solani AG 5. AG 4 isolates seem of little importance in field-grown tulips.</p><p>Anastomosis behaviour showed AG 2-t to be a homogeneous group, closely related to the heterogeneous group of AG 2-1 isolates. Pectic enzyme patterns discriminated tulip infecting AG 2-t isolates from AG 2 isolates not pathogenic to tulip. Geographically separated AG 2-t and AG 2-1 isolates, both pathogenic to tulip, differ in nucleotide number and sequence of ITS rDNA.</p><p>Differential interaction between AG 2-t isolates and tulip cultivars was highly influenced by experimental conditions. According to geostatistical analysis field sampling intensity could be reduced down to 10% and still provided adequate disease severity maps. Bare patches due to natural and artificial infestation declined during successive croppings of bulbs, whereas bulb rot tended to increase. Temporal niche differentiation is one explanation for the decline phenomenon.</p>
Het modelleren van competativeve substraatkolonisatie door Botrytis cinera en Ulocladium atrum.
Kessel, G.J.T. ; Haas, B.H. de; Lombaers-van der Plas, C.H. ; Kohl, J. ; Werf, W. van der; Fokkema, N.J. ; Rabbinge, R. - \ 1998
Gewasbescherming 29 (1998). - ISSN 0166-6495 - p. 159 - 159.
Interaction of four antagonistic fungi with Botrytis aclada in dead onion leaves: A comparative microscopic and ultrastructural study
Köhl, J. ; Bélanger, R.R. ; Fokkema, N.J. - \ 1997
Phytopathology 87 (1997). - ISSN 0031-949X - p. 634 - 642.
Risk assessment through quantitative detection of soil suppressiveness against plant diseases caused by Rhizoctonia solani AG 2-1, AG 2-t and AG 4, Fusarium solani f.sp. pisi, Thielaviopsis basicola, Aphanomyces euteiches, trichodorid nematodes and Meloidogyne hapla
Dijst, G. ; Oyarzun, P.J. ; Zoon, F.C. ; Kok, C.J. ; Gerlagh, M. ; Maas, P.W.Th. ; Fokkema, N.J. - \ 1997
In: Diagnosis and identification of plant pathogens / Dehne, H.W., Kluwer Academic Publishers - p. 247 - 251.
Schone gewasbescherming door het inzetten van vijanden en concurrenten.
Lenteren, J.C. van; Fokkema, N.J. ; Dik, A.J. - \ 1997
In: Kwaliteit en milieu in de glastuinbouw: stimulans tot vernieuwing / Marcelis, L.F.M., Haverkort, A.J., Wageningen : AB-DLO (AB-DLO thema's 4) - ISBN 9789073384538 - p. 75 - 89.
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