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 / 29

  • help
  • print

    Print search results

  • export

    Export search results

  • alert
    We will mail you new results for this query: q=Woets
Check title to add to marked list
Recirculatie bij snij-amaryllis (Hippeastrum) in drie teeltjaren (2013-2015) : Behoud plantgezondheid en voorkomen groeiremming bij hergebruik drainwater
Kromwijk, J.A.M. ; Burg, R. van der; Nijs, L. ; Overkleeft, J. ; Eveleens-Clark, B.A. ; Blok, C. ; Os, E.A. van; Baar, P.H. van; Grootscholten, M. ; Woets, F. - \ 2016
Bleiswijk : Wageningen UR Glastuinbouw (Rapport GTB 1398) - 88 p.
amaryllis - glastuinbouw - kasgewassen - kasproeven - teelt onder bescherming - emissie - hergebruik van water - afvalwaterbehandeling - afvalwater - recirculatiesystemen - lycorine - stikstof - voedingsstoffen - kunstmeststoffen - greenhouse horticulture - greenhouse crops - greenhouse experiments - protected cultivation - emission - water reuse - waste water treatment - waste water - recirculating systems - nitrogen - nutrients - fertilizers
In the Netherlands most crops grown in greenhouses reuse drain water. However, in the cultivation of amaryllis
cut flowers (Hippeastrum) little drainage water is being reused so far because of strong suspicions of inhibitory
substances in the drainage water. To reduce the emission of nutrients to the environment an experiment was
started on request of the amaryllis growers. In a greenhouse experiment drainage water of amaryllis was treated
with advanced oxidation and reused. This was compared with the reuse of drainage water treated with an UV
disinfector and a control treatment without the reuse of drainage water. In three years of cultivation, there was
no difference in production and no adverse effects were seen in crop growth. This research was funded by the
Dutch amaryllis growers, the ‘Topsector Tuinbouw en Uitgangsmaterialen’, the Product Board for Horticulture, the
project ‘Samenwerken aan Vaardigheden’ and Koppert.
Recirculatie amaryllis : behoud plantgezondheid en voorkomen groeiremming
Kromwijk, J.A.M. ; Overkleeft, J. ; Woets, F. ; Barendse, J. - \ 2014
glastuinbouw - siergewassen - amaryllis - snijbloemen - duurzaamheid (sustainability) - gewassen, groeifasen - kwaliteit na de oogst - recirculatiesystemen - substraten - perliet - teeltsystemen - greenhouse horticulture - ornamental crops - cut flowers - sustainability - crop growth stage - postharvest quality - recirculating systems - substrates - perlite - cropping systems
Begin maart 2013 zijn amaryllisbollen geplant en vanaf mei 2013 zijn drie behandelingen gestart: Hergebruik drainwater na UV-ontsmetting. Hergebruik drainwater na geavanceerde oxidatie (=waterstofperoxide én UV-ontsmetting) om groeiremmende stoffen af te breken en een Controlehandeling zonder recirculatie. Bij twee substraten, kleikorrels en perliet, en bij twee cultivars, Red Lion en Mont Blanc.
Recirculatie snij-amaryllis (Hippeastrum) in 1e teeltjaar : behoud plantgezondheid en voorkomen groeiremming bij hergebruik drainwater
Klein, M. ; Kromwijk, J.A.M. ; Woets, F. ; Overkleeft, J. - \ 2014
Wageningen : Wageningen UR (Rapport / Wageningen UR Glastuinbouw ) - 43
amaryllis - hippeastrum - snijbloemen - irrigatiewater - hergebruik van water - teeltsystemen - behandeling - proeven - plantenontwikkeling - cut flowers - irrigation water - water reuse - cropping systems - treatment - trials - plant development
In de teelt van snij-amaryllis (Hippeastrum) wordt nog weinig drainwater hergebruikt vanwege sterke vermoedens van groeiremmende stoffen in het drainwater. Om de hoeveelheid spuiwater terug te dringen is op verzoek van de amarylliscommissie onderzoek gestart naar mogelijkheden om drainwater van amaryllis her te gebruiken met zo min mogelijk risico op groeiremming. In een kasproef bij het GreenQ IC in Bleiswijk is in samenwerking met Wageningen UR Glastuinbouw, Groen Agro Control en LTO Groeiservice hergebruik van drainwater behandeld met geavanceerde oxidatie (=toediening van waterstofperoxide net voordat het drainwater door de UV-ontsmetter gaat) vergeleken met hergebruik van drainwater na UV-ontsmetting en met een controlebehandeling zonder hergebruik van drainwater. In het eerste teeltjaar was er geen verschil in productie en zijn geen nadelige effecten gezien op de gewasgroei. Het hergebruik van drainwater is voor een amaryllisgewas dat 3 à 4 jaar vast staat relatief kort geweest.
Recirculatie amaryllis: behoud plantgezondheid en voorkomen groeiremming
Kromwijk, J.A.M. ; Hein, P. ; Overkleeft, J. ; Woets, F. ; Verberkt, H. - \ 2013
amaryllis - bloembollen - recirculatiesystemen - waterkwaliteit - drainagewater - gewaskwaliteit - groeiremmers - emissie - cultuurmethoden - hergebruik van water - ornamental bulbs - recirculating systems - water quality - drainage water - crop quality - growth inhibitors - emission - cultural methods - water reuse
Powerpoint presentatie over een onderzoek naar het ontwikkelen van een recirculatiemethode voor amaryllis met behoud van plantgezondheid en het vookomen van groeiremming.
Recirculatie amaryllis: behoud plantgezondheid en voorkomen groeiremming
Kromwijk, J.A.M. ; Hein, P. ; Overkleeft, J. ; Woets, F. ; Verberkt, H. - \ 2013
Geïntegreerde bestrijding van trips en weekhuidmijten
Linden, A. van der; Klein, E. ; Woets, F. ; Vernooy, A. ; Gaag, V. van der - \ 2012
Wageningen UR Glastuinbouw/Syngenta Bioline
zomerbloemen - delphinium - alchemilla - insectenplagen - mijten - tarsonemidae - thripidae - organismen ingezet bij biologische bestrijding - roofmijten - neoseiulus - amblyseius - nederland - summer flowers - insect pests - mites - biological control agents - predatory mites - netherlands
Omdat meer kennis over natuurlijke bestrijders in zomerbloemen gewenst is, hebben de projectpartners een vijftal bijeenkomsten gehouden. Voor deze bijeenkomsten zijn de telers van zomerbloemen uitgenodigd. De bijeenkomsten werden begeleid door LTO Groeiservice, FytoConsult en DLV Plant. Naast de bijeenkomsten is onderzoek gedaan in Delphinium en Alchemilla naar de aanwezigheid en vestiging van roofmijten. In Delphinium komen weekhuidmijten voor en in Alchemilla komt trips voor als plaag. Spint kan eveneens in deze gewassen optreden. In beide gewassen werden drie soorten roofmijten geïntroduceerd: Neoseiulus alpinus, Neoseiulus reductus en Amblyseisus montdorensis. In Delphinium werden tijdens de waarnemingen geen weekhuidmijten gevonden en in Alchemilla was trips schaars. Neoseiulus reductus werd goed terug gevonden in Delphinium, in tegenstelling tot de andere soorten roofmijten. In Alchemilla werden alle drie de soorten roofmijten terug gevonden. Voorlopig lijkt Neoseiulus alpinus in het voordeel in Alchemilla, gevolgd door Neoseiulus reductus. Om hieromtrent duidelijkheid te krijgen en ook om een effect aan te tonen van de roofmijten op de plagen zijn meer waarnemingen noodzakelijk.
Detectie en beheersing van bacterierot veroorzaakt door Pseudomonas cattleyae in Phalaenopsis
Ludeking, D.J.W. ; Hamelink, R. ; Kromwijk, J.A.M. ; Schenk, M.F. ; Vermunt, A. ; Woets, F. - \ 2011
Bleiswijk : Wageningen UR Glastuinbouw (Rapporten GTB 1096) - 31
phalaenopsis - bacterieziekten - infectie - pseudomonas - bladvlekkenziekte - black spot - moleculaire technieken - relatieve vochtigheid - waterzuivering - invloeden - bacterial diseases - infection - leaf spotting - molecular techniques - relative humidity - water treatment - influences
Phalaenopsis growers suffer from mayor losses up to 20% due to bacterial spot. This bacterial infection in caused by the Acidovorax avenae subsp. cattleyae. In practice this bacterial disease is also known as Pseudomonas. This bacterium is causing black leaf spots with a yellow border. Pseudomonas cattleyae is very contagious and is promoted by high temperatures en moist conditions. In this project Groen Agro Control laboratory (Delfgauw) has developed a molecular analysis method to detect Pseudomonas cattleyae in different matrices. The influence of the relative humidity on the development of Pseudomonas cattleyae is investigated during this research. The results show that a relative humidity of 90% strongly promotes infection of the bacteria. A relative humidity of 75% shows no extra dispersion of Pseudomonas cattleyae compared to a greenhouse compartment with a continuous relative humidity of 60%. This knowledge offers the opportunity to safe energy in the cultivation of Phalaenopsis. During this research the effects of water treatments on the dispersion of Pseudomonas cattleyae have been investigated. The results show that a treatment with hydrogen peroxide (20 ppm) offers the best reduction of dispersion. This treatment turns out to be better than the control and all other treatments. This research has led to new insights about the dispersal and optimal growing conditions of this bacteria, but leads to new questions. Questions, about other different dosages and the effects of other water treatments, but also about the optimal level to promote plant growth and reduce bacterial infections, have to be investigated in new research.
Kasproef detectie en beheersing van Pseudomonas cattleyae in Phalaenopsis1219
Ludeking, D.J.W. ; Kromwijk, J.A.M. ; Woets, F. ; Vermunt, A. ; Schenk, M.F. - \ 2011
Kasproef detectie en beheersing van Pseudomonas cattleyae in Phalaenopsis
Ludeking, D.J.W. ; Kromwijk, J.A.M. ; Woets, F. ; Vermunt, A. ; Schenk, M.F. - \ 2010
phalaenopsis - acidovorax avenae - detectie - gewasbescherming - aantasting - bladeren - detection - plant protection - infestation - leaves
Informatieposter over een kasproef detectie en beheersing van Pseudomonas cattleyae in Phalaenopsis
Kasproef detectie en beheersing van Pseudomonas cattleyae in Phalaenopsis
Kromwijk, J.A.M. ; Ludeking, D.J.W. ; Woets, F. ; Vermunt, A. ; Schenk, M.F. - \ 2010
gewasbescherming - bacteriën - infecties - verspreide infecties - preventie - pseudomonas - phalaenopsis - glastuinbouw - plant protection - bacteria - infections - disseminated infections - prevention - greenhouse horticulture
Samenvatting van een kasproef getiteld "detectie en beheersing van Pseudomonas cattleyae in Phalaenopsis"
Onderzoek naar de verspreiding van de anjerbladroller, Cacoecimorpha pronubana (Huebner), in Nederland, vooral in het Zuidwesten, gedurende 1994
Woets, J. - \ 1995
Wilhelminadorp : Proefstation voor de Fruitteelt
insecten - plantenplagen - tortricidae - tuinbouw - plantenziekten - epidemiologie - distributie - nederland - microlepidoptera - insects - plant pests - horticulture - plant diseases - epidemiology - distribution - netherlands
Development of thresholds based on pheromone trap catches for control of leafroller moths in apple orchards: a first report
Minks, A.K. ; Deventer, P. van; Woets, J. ; Remortel, E. van - \ 1995
Proceedings Experimental and Applied Entomology 6 (1995). - p. 125 - 132.
Host plant adaptation in the glasshouse whitefly
Thomas, D.C. - \ 1993
Agricultural University. Promotor(en): Joop van Lenteren. - S.l. : Thomas - ISBN 9789054850496 - 129
insecten - insectenplagen - aleyrodidae - gastheer parasiet relaties - planten - adaptatie - trialeurodes vaporariorum - insects - insect pests - host parasite relationships - plants - adaptation
<p><strong>Introduction</strong><br/>Although much research towards the development and understanding of plant resistance and biological control as pest control strategies has been done, few studies have concentrated upon the interaction between these two control methods where they are combined. However, ecological research has provided a firm framework in which biological control and plant resistance can be studied within a tritrophic context. Such a framework emphasises how the changes in the response of a pest to its host plant, may consequently affect the dynamics of the interaction between it and its natural enemy. Conversely, how the use of a natural enemy to maintain pest density to below a certain level, may affect the interaction between the pest and its host plant. Within this framework, the pest's potential to adapt to the host plant, needs to be considered. Where adaptation occurs, the resistance of that host plant to the pest diminishes and also the efficacy of the biological control agent (s) used to control that pest may be affected. These tritrophic systems, should be studied from the viewpoint of evolutionary ecology. This stresses the adaptive character of the interactions, more than a pure ecological approach, which until now has provided the basis for studying the population dynamics of pest control systems.<p>In relation to this tritrophic approach to pest control, the system <em>Encarsia formosa</em> (parasitoid) - <em>Trialeurodes vaporariorum</em> (pest; common name, glasshouse whitefly) - host plant was taken as a model system. In this thesis, aspects of the bi-trophic interaction between whitefly and its host plants are described. This system is a subject of continuing studies at the Department of Entomology in Wageningen. Here, research has concentrated upon preference and performance aspects of whitefly- plant relationships (van Lenteren and Noldus, 1990), the parasitization behaviour and parasitizing efficiency of <em>E. formosa</em> (Noldus and van Lenteren, 1990), the improved resistance of host plants to whitefly (de Ponti et. al., 1990) and the reduction of incompatibility problems of host plant resistance with respect to the deployment of <em>E. formosa</em> (van Lenteren and de Ponti, 1991). These studies have provided a fundamental basis for the improvement of whitefly control in commercial glasshouses by <em>E. formosa</em> (van Lenteren and Woets, 1988). Earlier studies e.g. van Boxtel et. al., 1978, had indicated the potential of whitefly to adapt from one host plant to another, within its host range. However the rate at which adaptation would occur and whether or not genetically distinct races of the glasshouse whitefly exist in relation to this process was not clear from such studies. The ability of whitefly to adapt rapidly to new host plants, or the existence of distinct races of whitefly in relation to this process may have repercussions upon the efficacy of whitefly control by <em>E. formosa</em> .<p><strong>Research questions and experiments</strong><br/>The studies described in this thesis, aimed to answer the following questions:<br/>1 At what rate is a whitefly likely to adapt, when transferred from one host plant to another (chapter 2) ?<br/>2 Do 'trade-offs~ occur during adaptation with respect to the host plant from which whitefly originated (chapter 2) ?<br/>3 Can the rearing of whitefly upon a certain host plant, 'pre-condition' them to adapt to another host plant (chapter 3) ?<br/>4 Does the host plant from which whitefly originates influence its preference for other host plants (chapter 4) ?<br/>5 Do genetically distinct races of whitefly exist (chapter 5) ?<br/> <p>The whitefly's rate of host plant adaptation was assessed by measuring changes in life history parameters over consecutive whitefly generations. The relative contributions of genotypic and phenotypic variation to the adaptation process were not assessed. This was a deliberate decision, because a simple measurement of changes in ecological parameters over consecutive whitefly generations would give an overall indication of intra and intergenerational variability, that could subsequently be used to calculate the degree of replication required, to accurately ascertain each component of genetic variation. Egg laying, immature mortality and immature development time, were assessed. These are all indicative of population fitness with respect to the net reproductive rate of the population.<p>The major objective was to develop a method for assessing the rate and extent of host plant adaptation by whitefly. This required the solving of many logistical problems related to the rearing of insect and plant material, so that the material used in all whitefly generations was comparable. All experiments were conducted in a climate cell under standardised conditions of light, temperature and relative humidity. Whiteflies were maintained as rearings with discrete generations. In each generation tested, whiteflies were removed from each respective rearing using an aspirator. They were lightly anaesthetized under carbon dioxide and a single male and female were placed in a leaf cage, that was clipped to the appropriate host plant. There were typically 20 to 40 such leaf cages per whitefly population per host plant tested. After 24 hours the whiteflies and leaf cages were removed and the number of eggs laid per female counted. The development of the eggs was then followed to assess immature mortality and development time. The method developed was used to assess the rate of adaptation of a whitefly population originating from gerbera, to four cucumber cultivars. 'Trade-offs' with respect to the original host plant gerbera were sought once adaptation to cucumber had been ascertained. The same methodology was used to assess whether or not whitefly could be induced to adapt to a Dutch cultivar of sweet pepper and whether the host plant from which whitefly originated influenced this process or not.<p>The preference of whiteflies reared upon three different host plants (cucumber, gerbera and sweet pepper), was assessed in a multiple choice test, to determine if the host plant from which whitefly originates influences its preference for other host plants with respect to their suitability for whitefly.<p>Finally it was attempted to develop an electrophoretic technique for the glasshouse whitefly using starch and polyacrylamide gel electrophoresis methods for assessing variation in isoenzyme allele frequencies. With this technique, it may be possible to conduct tests for the existence of genetically distinct races between whitefly populations, based upon the genetic distances between them.<p><strong>Results</strong><br/>Whiteflies originating from gerbera and exposed to cucumber showed adaptation within one whitefly generation. Thereafter the whitefly performance fluctuated so well between cucumber cultivars as over successive whitefly generations. The degree of variation hereby was circa 50 % in the number of eggs laid per female per 24 hours, circa 10 % in the immature development time (in days) and circa 25% in the overall percentage immature mortality. No 'trade-offs' were found, but this investigation was quite cursory in nature and examined just one possibility i.e. that between gerbera and cucumber. 'Trade-offs' may well be detected for other whitefly populations.<p>The work with whitefly upon Dutch sweet pepper indicated that where whiteflies were reared for a single generation upon <em>Lycopersicon hirsutum</em> cv. glabratum prior to being transferred to sweet pepper, their performance was much better than where they had been reared upon gerbera, cucumber or tomato. Although the plant upon which the whiteflies were reared prior to being transferred to sweet pepper influenced their subsequent performance upon this host plant, this phenomenon did not appear to be related to the quality of the host plants concerned with respect to whitefly performance. Rather the specific secondary plant substances which they contained seems to be of importance.<p>The preference tests indicated that the influence of the host plant was such that whiteflies originating from a given host plant, exhibited a greater preference for that host plant relative to that of other whitefly populations. However independent of which host plant a whitefly population originated from, there was an invariate rank order of preference of cucumber>gerbera>sweet pepper. This rank preference, is the same as that of the suitability of these host plants with respect to whitefly performance.<p>The attempts over several months, to develop a reliable electrophoresis technique for the glasshouse whitefly were not successful. However there is still much scope for further improvements. I did not develop this further because of time constraints.<p><strong>Conclusions</strong><br/>The problems faced in developing a suitable method for assessing host plant adaptation emphasised the importance of consistently using highly standardised plant and insect material of high quality. The glasshouse whitefly appears to adapt readily to plants in its host range, within a few generations. Upon more marginal host plants such as for example sweet pepper, the rate of adaptation appears to be lower than that upon better quality host plants and is influenced by the host plant from which the whitefly originates. Independent from which host plant whitefly originates, that its rank order of preference, so well performance will be cucumber>gerbera>sweet pepper. As the quality of the host plant from which whitefly originates decrease, then the magnitude of the difference between host plants within this rank order also decrease. Life history parameters could clearly be used to indicate differences in whitefly performance upon host plants. The rate at which a population adapts to a host plant measured by these parameters, may provide a good indicator as to the durability of a host plant's inherent resistance to whitefly. However all such tests upon whitefly performance should be conducted over several consecutive whitefly generations so as to account for the between generation variation, even where whitefly is already adapted to the host plant in question. In 'no-choice' tests of whitefly performance, care should be taken to differentiate between laying and non-laying females which indicate respectively antibiosic and antixenosic aspects of host plant resistance. Finally research must still be done to establish whether or not genetically distinct races of the glasshouse whitefly exist and also the relative contributions of genetic and phenotypic variation to whitefly performance and adaptation.<p><strong>Practical implications</strong><br/>Although the relationship between observations made in my studies and their applicability in the commercial glasshouse situation has yet to be determined, some speculations are now made. If whiteflies are transferred from one crop to another under commercial glasshouse conditions, e.g. through infected plant material or through whiteflies migrating into a glasshouse through air ventilators, then these whiteflies would adapt to the crop concerned within a few whitefly generations, unless the crop was marginal with respect to whitefly use e.g. sweet pepper. In such a case, the chances of whiteflies becoming adapted to the crop are slight. If however air ventilators are covered with insect proof gauze and hygiene standards with respect to the movement and disposal of plant material are strictly maintained, the likelihood of whitefly movement between glasshouses will be reduced. Where more than one cultivar of an ornamental crop is grown in the same glasshouse, the possibility arises that whitefly will adapt to one cultivar and in thus doing become pre-conditioned to adapt to other cultivars in the glasshouse, to which it might not otherwise have adapted.
Biological and integrated pest control in greenhouses.
Lenteren, J.C. van; Woets, J. - \ 1988
Annual Review of Entomology 33 (1988). - ISSN 0066-4170 - p. 239 - 269.
The parasite-host relationship between Encarsia formosa and Trialeurodes vaporariorum. XXIV. Effectiveness of Encarsia formosa in the greenhouse at low temp.
Hulspas-Jordaan, P.M. ; Christochowitz, E.E. ; Woets, J. ; Lenteren, J.C. van - \ 1987
Journal of Applied Entomology 103 (1987). - ISSN 0931-2048 - p. 368 - 378.
Invasions of pest beneficial insects in The Netherlands.
Lenteren, J.C. van; Woets, J. ; Grijpma, P. ; Ulenberg, S.A. ; Minkenberg, O.P.J.M. - \ 1987
Proceedings of the Koninklijke Nederlandse Akademie van Wetenschappen. Serie C: Biological and medical sciences 90 (1987). - ISSN 0023-3374 - p. 51 - 58.
Chrysocharis parksi in commercial greenhouses for the biological control of leafminers, L. trifolii, on tomatoes; case studies and sampling techniques.
Frijter, A.J.M. ; Minkenberg, O.P.J.M. ; Woets, J. ; Ravensberg, W.J. - \ 1986
Mededelingen - Universiteit Gent, Faculteit Landbouwkundige en Toegepaste Biologische Wetenschappen 51 (1986). - ISSN 1373-7503 - p. 987 - 998.
Regulatie van de Floridamineerder, Liriomyza trifolii Burgess (Diptera Agromyzidae) door de Noordamerikaanse parasiet Chrysocharis parksi Crwaford (Hymenoptera; Eulophiadae) in kleine kassen (1983)
Linden, A. van der; Woets, J. - \ 1985
Naaldwijk : Proefstation voor Tuinbouw onder Glas (Intern verslag / Proefstation voor Tuinbouw onder Glas nr. 22) - 6
The use of Encarsia formosa to control the greenhouse whitefly in Europe
Lenteren, J.C. van; Woets, J. - \ 1984
In: Abstract XVIIth Int. Congr. Entomology Hamburg - p. 771 - 771.
Waarnemingen in praktijkkassen met een tomateteelt in veenbalen in 1982 om het verloop te volgen van potentiële gevallen van natuurlijke bestrijding van de tomatemineervlieg, Liriomyza Bryoniae Kalt., door zijn natuurlijke vijanden
Linden, A. van der; Woets, J. - \ 1983
Naaldwijk : Proefstation voor Tuinbouw onder Glas (Intern verslag / Proefstation voor Tuinbouw onder Glas nr. 18) - 3
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.