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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    Optimal leaf area leads to higher production and higher income : Don't prune too many tomato leaves
    Heuvelink, E. ; Kierkels, T. - \ 2014
    In Greenhouses : the international magazine for greenhouse growers 3 (2014)2. - ISSN 2215-0633 - p. 52 - 53.
    glastuinbouw - solanum lycopersicum - plantenontwikkeling - bladoppervlakte - ontbladering - assimilatie - netto-assimilatiesnelheid - groenten - greenhouse horticulture - solanum lycopersicum - plant development - leaf area - defoliation - assimilation - net assimilation rate - vegetables
    Good light interception is the first step to good production. For that you need sufficient leaf area in the greenhouse. But it’s difficult for a grower to determine how much leaf surface area is present. Research is shedding new insight into this aspect.
    High level of molecular and phenotypic biodiversity in Jatropha curcas from Central America compared to Africa, Asia and South America
    Montes Osorio, L.R. ; Torres Salvador, A.F. ; Jongschaap, R.E.E. ; Azurdia, C. ; Berduo, J. ; Trindade, L.M. ; Visser, R.G.F. ; Loo, E.N. van - \ 2014
    BMC Plant Biology 14 (2014). - ISSN 1471-2229
    net assimilation rate - relative growth-rate - genetic diversity - leaf-area - germplasm collection - biofuel plant - l. accessions - markers - aflp - variability
    Background The main bottleneck to elevate jatropha (Jatropha curcas L.) from a wild species to a profitable biodiesel crop is the low genetic and phenotypic variation found in different regions of the world, hampering efficient plant breeding for productivity traits. In this study, 182 accessions from Asia (91), Africa (35), South America (9) and Central America (47) were evaluated at genetic and phenotypic level to find genetic variation and important traits for oilseed production. Results Genetic variation was assessed with SSR (Simple Sequence Repeat), TRAP (Target Region Amplification Polymorphism) and AFLP (Amplified fragment length polymorphism) techniques. Phenotypic variation included seed morphological characteristics, seed oil content and fatty acid composition and early growth traits. Jaccard’s similarity and cluster analysis by UPGM (Unweighted Paired Group Method) with arithmetic mean and PCA (Principle Component Analysis) indicated higher variability in Central American accessions compared to Asian, African and South American accessions. Polymorphism Information Content (PIC) values ranged from 0 to 0.65. In the set of Central American accessions. PIC values were higher than in other regions. Accessions from the Central American population contain alleles that were not found in the accessions from other populations. Analysis of Molecular Variance (AMOVA; P¿
    Physiological mechanisms in plant growth models: do we need a supra-cellular systems biology approach?
    Poorter, H. ; Anten, N.P.R. ; Marcelis, L.F.M. - \ 2013
    Plant, Cell & Environment 36 (2013)9. - ISSN 0140-7791 - p. 1673 - 1690.
    nitrogen-use efficiency - net assimilation rate - leaf-area - elevated co2 - carbon gain - tomato plants - gas-exchange - chemical-composition - biomass production - critical-appraisal
    In the first part of this paper, we review the extent to which various types of plant growth models incorporate ecophysiological mechanisms. Many growth models have a central role for the process of photosynthesis; and often implicitly assume C-gain to be the rate-limiting step for biomass accumulation. We subsequently explore the extent to which this assumption actually holds and under what condition constraints on growth due to a limited sink strength are likely to occur. By using generalized dose–response curves for growth with respect to light and CO2, models can be tested against a benchmark for their overall performance. In the final part, a call for a systems approach at the supra-cellular level is made. This will enable a better understanding of feedbacks and trade-offs acting on plant growth and its component processes. Mechanistic growth models form an indispensable element of such an approach and will, in the end, provide the link with the (sub-)cellular approaches that are yet developing. Improved insight will be gained if model output for the various physiological processes and morphological variables (‘virtual profiling’) is compared with measured correlation networks among these processes and variables. Two examples of these correlation networks are presented
    Causes and consequences of variation in leaf mass per area (LMA): a meta-analysis
    Poorter, H. ; Niinemets, U. ; Poorter, L. ; Wright, I.J. ; Villar, H. - \ 2009
    New Phytologist 182 (2009)3. - ISSN 0028-646X - p. 565 - 588.
    relative growth-rate - net assimilation rate - dry-matter content - chemical-composition - rain-forest - photosynthetic acclimation - construction costs - shade-tolerance - woody-plants - co2 concentration
    Here, we analysed a wide range of literature data on the leaf dry mass per unit area (LMA). In nature, LMA varies more than 100-fold among species. Part of this variation (c. 35%) can be ascribed to differences between functional groups, with evergreen species having the highest LMA, but most of the variation is within groups or biomes. When grown in the same controlled environment, leaf succulents and woody evergreen, perennial or slow-growing species have inherently high LMA. Within most of the functional groups studied, high-LMA species show higher leaf tissue densities. However, differences between evergreen and deciduous species result from larger volumes per area (thickness). Response curves constructed from experiments under controlled conditions showed that LMA varied strongly with light, temperature and submergence, moderately with CO2 concentration and nutrient and water stress, and marginally under most other conditions. Functional groups differed in the plasticity of LMA to these gradients. The physiological regulation is still unclear, but the consequences of variation in LMA and the suite of traits interconnected with it are strong. This trait complex is an important factor determining the fitness of species in their environment and affects various ecosystem processes.
    Relating leaf photosynthetic rate to whole-plant growth: drought and shade effects on seedlings of four Quercus species
    Quero Perez, J.L. ; Villar, R. ; Marañón, T. ; Zamora, R. ; Vega, D. ; Sack, L. - \ 2008
    Functional Plant Biology 35 (2008)8. - ISSN 1445-4408 - p. 725 - 737.
    net assimilation rate - light-dependent changes - biomass allocation - seed-mass - rain-forest - woody seedlings - tree seedlings - gas-exchange - trade-offs - niche differentiation
    Understanding the impacts of combined resource supplies on seedlings is critical to enable prediction of establishment growth, and forest dynamics. We investigated the effects of irradiance and water treatments on absolute growth, and relative growth rate (RGR) and its components, for seedlings of four Quercus species differing in leaf habit and with a wide variation in seed mass. Plants were grown for 6.5 months at three levels of irradiance (100, 27, and 3% daylight), and treated during the last 2.5 months with two watering treatments (frequent watering v. suspended watering). Both shade and drought reduced seedling growth rates, with a significant interaction: under full irradiance the drought treatment had a stronger impact on RGR and final biomass than under deep shade. For three species, seed mass was positively related to absolute growth, with stronger correlations at lower irradiance. The evergreen species grew faster than the deciduous species, though leaf habit accounted for a minor part of the interspecific variation in absolute growth. Seedling biomass was determined positively either byRGRor seed mass;RGRwas positively linked with net assimilation rate (NAR) and leaf mass fraction (LMF), and seed mass was negatively linked with RGR and LMF, but positively linked with NAR. Seedling RGR was not correlated with light-saturated net photosynthetic rate, but was strongly correlated with the net carbon balance estimated, from photosynthetic light-response curves, considering daily variation in irradiance. These findings suggest an approach to applying short-term physiological measurements to predict the RGR and absolute growth rate of seedlings in a wide range of combinations of irradiance and water supplies. Additional keywords: biomass allocation, carbon balance, growth analysis, leaf habit, Mediterranean oak, relative growth rate, seed mass, specific leaf area.
    Verfijnd rekenmodel voor belichting in rozen blijft toekomst muziek : beslissingsondersteunend model geeft 10-15% besparing
    Staalduinen, Jan van; Raaphorst, M.G.M. - \ 2007
    Onder Glas 4 (2007)5. - p. 78 - 79.
    groeimodellen - groei - rozen - belichting - lichtsterkte - efficiëntie - optimalisatie - groeianalyse - plantenfysiologie - netto-assimilatiesnelheid - beslissingsondersteunende systemen - energiebesparing - glastuinbouw - snijbloemen - growth models - growth - roses - illumination - light intensity - efficiency - optimization - growth analysis - plant physiology - net assimilation rate - decision support systems - energy saving - greenhouse horticulture - cut flowers
    In opdracht van het ministerie van LNV en PT onderzocht Wageningen UR Glastuinbouw de behoefte van rozentelers aan een beslissingsondersteunend model om energie-efficiëntie van belichten te optimaliseren. Onderzoeker Raaphorst ervoer dat sommige telers enthousiast zijn. Ondanks een verwacht besparingspotentieel van 10 tot 15% heeft maar een beperkte groep rozentelers interesse in een beslissingsondersteunend rekenmodel voor het optimaliseren van de belichtingsinstellingen. Eisen aan het rekenmodel zijn eenvoudige bediening, bewezen praktijkwaarde, rasafhankelijke instellingen, input vanuit de bedrijfsadministratie en professionele ondersteuning. Voor vervolgonderzoek is dat een te smalle basis. Onderzoekers en telers verwachten wel dat het draagvlak over enkele jaren breder is
    Suiker legt soms een meterslange weg af door de plant
    Arkesteijn, M. ; Dieleman, J.A. - \ 2006
    Onder Glas 3 (2006)11. - p. 27 - 29.
    komkommers - assimilatie - netto-assimilatiesnelheid - plantenfysiologie - teelt onder bescherming - glastuinbouw - groenten - cucumbers - assimilation - net assimilation rate - plant physiology - protected cultivation - greenhouse horticulture - vegetables
    Verslag van onderzoek door PRI naar de verdeling van assimilaten in komkommer. De meeste assimilaten gaan naar de grootste vruchten. Uit weeg- en telonderzoek blijkt dat de afstand tussen de vruchten en het fotosynthetiserende blad niet te groot mag worden om productieverlies te voorkomen. Gegevens in bijgaande figuur: De procentuele verdeling van de hoeveelheid 13C in de plant over de verschillende organen, 24 uur na de start van de behandeling op 9 maart
    Optimaal bladoppervlak levert geld op : voorzichtig zijn met teveel blad plukken bij tomaat
    Heuvelink, E. ; Kierkels, T. - \ 2005
    Onder Glas 2 (2005)2. - p. 14 - 15.
    tomaten - solanum lycopersicum - plantenontwikkeling - bladoppervlakte - bladoppervlakte-index - ontbladering - assimilatie - netto-assimilatiesnelheid - glastuinbouw - groenten - tomatoes - solanum lycopersicum - plant development - leaf area - leaf area index - defoliation - assimilation - net assimilation rate - greenhouse horticulture - vegetables
    Uit onderzoek blijkt dat sommige tomatentelers tot 10% meer licht weten te vangen dan andere telers. In principe betekent dat ook een 10% hogere productie. Het onderzoek bewijst: zorg voor een hoge lichtonderschepping door het gewas. Dat zorgt voor een optimale productie en optimale benutting van duur assimilatielicht. Gegevens in bijgaande grafiek: De hoeveelheid licht die het gewas onderschept loopt op naarmate het aantal vierkante meters blad per grondoppervlak groter is, tot een bepaalt maximum is bereikt
    A genetic analysis of relative growth rate and underlying components in Hordeum spontaneum
    Poorter, H. ; Rijn, C.P.E. ; Vanhala, T. ; Verhoeven, K.J.F. ; Jong, Y.E.M. de; Stam, P. ; Lambers, H. - \ 2005
    Oecologia 142 (2005)3. - ISSN 0029-8549 - p. 360 - 377.
    carbon-isotope discrimination - net assimilation rate - trait locus analysis - wild barley - seed size - leaf-area - dioxide concentration - quantitative traits - aflp markers - qtl analysis
    Species from productive and unproductive habitats differ inherently in their relative growth rate (RGR) and a wide range of correlated quantitative traits. We investigated the genetic basis of this trait complex, and specifically assessed whether it is under the control of just one or a few genes that can act as 'master switches` by simultaneously affecting a range of traits in the complex. To address this problem, we crossed two Hordeum spontaneum lines originating from two habitats that differ in productivity. The F-3 offspring, in which parental alleles are present in different combinations due to recombination and segregation, was analysed for RGR and its underlying components ( leaf area ratio, unit leaf rate, photosynthesis, respiration), as well as a number of other physiological and morphological parameters. For this intra-specific comparison, we found a complex of positively and negatively correlated traits, which was quite similar to what is generally observed across species. A quantitative trait loci (QTL) analysis showed three major and one minor QTL for RGR. Most other variables of the growth-trait complex showed fewer QTLs that were typically scattered over various locations on the genome. Thus, at least in H. spontaneum, we found no evidence for regulation of the trait complex by one or two master switches.
    Teelthandleiding zetmeelaardappelen: : factoren die de productiesnelheid beïnvloeden
    Veerman, A. - \ 2003 2003 (2003)15 dec..
    aardappelen - pootknollen - droge stof - productie - fotosynthese - netto-assimilatiesnelheid - fabrieksaardappelen - akkerbouw - teelthandleidingen - potatoes - seed tubers - dry matter - production - photosynthesis - net assimilation rate - starch potatoes - arable farming - cultivation manuals
    De droge stofproductie van een gewas wordt gevormd door de productie per dag maal het aantal groeidagen. Voor de knolopbrengst zijn de snelheid van fotosynthese en ademhaling, de verdeling van de droge stof over loof, wortels en knollen en het droge stofgehalte van de knollen van belang. In dit hoofdstuk wordt besproken welke factoren van invloed zijn op de productiesnelheid van de aardappelplant.
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