Adaptation and acclimation of seed performance
Souza Vidigal, D. De - \ 2015
Wageningen University. Promotor(en): Harro Bouwmeester, co-promotor(en): Leonie Bentsink; Henk Hilhorst. - Wageningen University - ISBN 9789462575943 - 156
zaden - zaadkwaliteit - zaadkieming - klimaatverandering - adaptatie - arabidopsis - kiemrust - klimaatadaptatie - seeds - seed quality - seed germination - climatic change - adaptation - arabidopsis - seed dormancy - climate adaptation
Environmental regulation of seed performance
He, H. - \ 2014
Wageningen University. Promotor(en): Harro Bouwmeester; J.C.M. Smeekens, co-promotor(en): Henk Hilhorst; Leonie Bentsink. - Wageningen University : Wageningen University - ISBN 9789462570337 - 185
arabidopsis - zaden - kiemrust - zaadkieming - milieueffect - genetica - genotypen - temperatuur - arabidopsis - seeds - seed dormancy - seed germination - environmental impact - genetics - genotypes - temperature
The seed stage is an essential episode in the life cycle of higher plants. The environmental cues that seeds experience during their development are important components of their life history. The parental environment, from pre-fertilization until seed dispersal affects performance of the dry mature seed and, therefore, affects the life cycle of the next generation. The evolutionary response to environmental perturbations has resulted in genetic changes in order to increase the fitness of the population, which is called ‘adaptation’. The aims of this study were to increase our understanding of how environments regulate seed performance, both on the long term, i.e. through adaptation of seed performance traits to local conditions and on the short term, i.e. by acclimation of plants to different seed maturation environments.
Seed germination methods for native Caribbean trees and shrubs : with emphasis on species relevant for Bonaire
Burg, W.J. van der; Freitas, J. ; Debrot, A.O. - \ 2014
Wageningen : Plant Research International, Business Unit Agrosystems Research (Report / Plant Research International 551) - 60
zaadkieming - bomen - struiken - zaden - opslag van zaden - zaad verzamelen - kiemrust - bonaire - caribisch gebied - seed germination - trees - shrubs - seeds - seed storage - seed collection - seed dormancy - bonaire - caribbean
This paper is intended as a basis for nature restoration activities using seeds of trees and (larger) shrubs native to Bonaire with the aim of reforestation. It describes the main seed biology issues relevant for species from this region, to facilitate decisions on time and stage of harvesting, safe storage, breaking dormancy and germinating seeds and planting the young trees in the field. The paper also emphasises that natural process of seedling establishment and succession must be observed in order to be successful. The choice of species and method of protection once planted in nature will prove essential. The paper ends with stressing that such a reforestation activity needs to be planned far ahead: seeds must be collected from tree species taking care of genetic diversity and their storage potential. Recalcitrant seeds (see paper) must be treated carefully and in a different way.
Imaging genetics of seed performance
Joosen, R.V.L. - \ 2013
Wageningen University. Promotor(en): Linus van der Plas, co-promotor(en): Henk Hilhorst; Wilco Ligterink. - S.l. : s.n. - ISBN 9789461734976 - 196
zaden - zaadkieming - kiemkracht - genetica - kiemrust - genomica - arabidopsis thaliana - moleculaire genetica - moleculaire biologie - loci voor kwantitatief kenmerk - seeds - seed germination - germinability - genetics - seed dormancy - genomics - arabidopsis thaliana - molecular genetics - molecular biology - quantitative trait loci
The Netherlands has a long history of plant breeding which has resulted in a leading position in the world with respect to the sales of vegetable seeds. Nowadays high-tech methods are used for crop-production which demands high standards for the quality of the starting materials. While breeding has mainly focused on crop yield and disease resistance in the past, it now becomes equally important to create seeds that rapidly and uniformly germinate under a wide range of production environments. A better understanding of the molecular processes that are underlying seed quality is a crucial first step to enable targeted breeding. In this thesis we describe the results of new methods that were used to map the genetics of seed germination.
For this research we have used the leading plant science model species Arabidopsis thaliana which has a short generation time and a fully sequenced genome. Further, the large scientific community working on this model species is providing a wealth of resources ranging from large collections of worldwide accessions, genetic mapping populations, mutants and knowledge about gene, protein and metabolite action. A disadvantage of using Arabidopsis is the small size of the seeds, which requires evaluation of the germination of individual seeds with the use of magnifying glasses. This problem has been solved by using image analysis to create an automated procedure to obtain detailed information for parameters such as rate, uniformity and maximum germination. This procedure, called ‘the Germinator’, is described in Chapter 2 and has been enthusiastically adopted by the seed community.
Plants cannot walk away from the environment at which the seed is dispersed. To survive and to enable reproduction, plants adapt to the prevailing environment which results in considerable genetic variation. This ‘natural variation’ is a great resource to study the mechanisms of adaptation. In Chapter 3 we have used two distinct Arabidopsis accessions, one originating from Germany (Bayreuth) and the other from high altitude in the Pamiro-Alay Mountains in Tadjikistan (Shahdara). In contrast to the Bayreuth accession, the Shahdara accession is well adapted to survive harsh conditions and is known to be stress tolerant to a range of environments. A genetic mapping (recombinant inbred line; RIL) population, consisting of 165 lines, that was derived from these two accessions is therefore particularly suitable to locate the genomic regions with genetic differences that influence seed germination. Such genomic regions are commonly referred to as quantitative trait loci (QTL). With help of the Germinator system we were able to evaluate germination of this RIL population under many different conditions. This resulted in a description of the ‘genetic landscape of seed performance’ in which we identified many QTLs for Arabidopsis seed germination.
QTL regions are often large and identification of the causal gene requires intensive follow up research. We therefore aimed for a high throughput analysis using modern ‘omics’ techniques to analyze differences in metabolite levels and gene expression between the lines. A method to classify and visualize the vast amount of data derived from such an approach is described in Chapter 4. The so called genetical ‘omics’ experiments are expensive and therefore often force researchers to limit their study to a single developmental stage or environment only. A novel generalized setup overcomes this limitation and was tested for metabolite level changes in Chapter 5. This setup offers a unique reduction of experimental load with minimal effect on statistical power and is of great potential in the field of system genetics. Four different developmental stages of seed germination were tested in the RIL population. This approach resulted in a large dataset for which efficient analytical procedures were lacking. Thus, Chapter 5 also includes a description of a newly developed statistical procedure to analyze this type of data. The same approach and material were used in Chapter 6 to evaluate the genetics of genome wide gene expression.
Another approach to zoom in on the molecular mechanisms underlying seed performance is described in Chapter 7. Here, the genetic diversity was maximized by using 360 different Arabidopsis accessions which had been subjected to ultra-high density genotyping. In potential, such a genome wide association (GWA) study can provide high resolution mapping of genetic variation resulting in only a few candidate genes per association for the phenotype under study. Although we were able to replicate experiments over two years with a high level of heritability, no significant associations were found. This emphasizes the need to critically review the power of such an approach for traits that are expected to be determined by many small effect loci.
Finally, closing in on the molecular mechanisms underlying the seed traits that we studied might be possible by a full integration of the datasets that were described in the different chapters. Two examples that show the potential and the complexity of such integration are described in the General Discussion (Chapter 8). Research focused on seed quality does not end here but has gained an impulse by the described new methods and hypotheses to continue on both the fundamental and applied level in the coming years.
Dormancy cycling in seeds: mechanisms and regulation
Claessens, S.M.C. - \ 2012
Wageningen University. Promotor(en): Linus van der Plas, co-promotor(en): Henk Hilhorst; P.E. Toorop. - S.l. : s.n. - ISBN 9789461731906 - 161
sisymbrium officinale - arabidopsis thaliana - kiemrust - zaden - genen - levenscyclus - slaaptoestand - membranen - metabolisme - sisymbrium officinale - arabidopsis thaliana - seed dormancy - seeds - genes - life cycle - dormancy - membranes - metabolism
The life cycle of most plants starts, and ends, at the seed stage. In most species mature seeds are shed and dispersed on the ground. At this stage of its life cycle the seed may be dormant and will, by definition, not germinate under favourable conditions (Bewley, 1997).
Seasonal dormancy cycling is a characteristic found in plant seeds. Being able to cycle in and out of dormancy allows the seed to survive decades or even centuries, allowing germination to be spread over time, but only when optimal conditions are available, not only for germination but especially for seedling establishment. In this thesis we have attempted to further elucidate the mechanisms behind dormancy, germination and dormancy cycling.
Sisymbrium officinale seeds need nitrate and light to start germination (Chapter 2, 3, 4, 6). Nitrate acts in part by reducing the abscisic acid (ABA) levels (a plant hormone that elevates dormancy levels). The action of light and nitrate can also be reached by applying gibberellins (GAs) to the seeds (Chapter 2, 3, 4, 6). GAs are capable of inducing enzymes that hydrolyze the ensdosperm walls (Debeaujon and Koornneef, 2000; Chen and Bradford, 2000; Nonogaki et al., 2000; Manz et al., 2005) In this way GAs could be involved in lowering the physical restrictions imposed by the resistance of the seed coat and the endosperm. On the other hand, GAs may also increase the embryo growth potential.
For successful survival of the dormant seed, metabolic activity is reduced to avoid rapid depletion of reserves. The metabolic activity of the seed was measured using electron paramagnetic resonance (EPR), with TEMPONE as a spin probe, and the respiratory activity was measured with the Q2-test (Chapter 2).We showed that primary dormancy was accompanied by hardly any metabolic or respiratory activity, and this increased considerably when dormancy was broken by nitrate. However, when the light pulse was not given and the seeds had become secondary dormant the metabolic activity slowed down.
Regulation of dormancy is tightly linked with abiotic stress factors from the environment. The regulation and survival of the seed under stress conditions is largely dependent on the composition of the cytoplasm. We tested this by EPR, using carboxyl-proxyl (CP) spin probe (Chapter 4). The primary dormant and sub-dormant seeds possessed a higher viscosity than the germinating seeds. The viscosity of secondary dormant seeds appeared intermediate; however, the ease at which the vitrified water melted was similar to that of primary dormant seeds. As a result of the differences in viscosity, the temperature of vitrified water melting differed between the different dormancy states. The changes in cytoplasmic viscosity and vitrified water melting may be linked to changes in metabolism and the content of high molecular weight compounds.
As membranes are the primary target for temperature perception, they are often implicated in regulating dormancy. Therefore, Hilhorst (1998) put forward a hypothesis in which changes in responsiveness to dormancy breaking factors like nitrate and light was a function of cellular membrane fluidity. In Chapter 3 we indeed showed that dormancy is a function of membrane fluidity. Primary dormant seeds of Sisymbrium officinale appeared to have very rigid membranes, whereas breaking dormancy increased membrane fluidity considerably. However, when sub-dormant seeds became secondary dormant membrane fluidity decreased again, but not to the rigidity seen in primary dormant seeds. One of the most common ways in which cells control membrane fluidity is by homeoviscous adaptation with the help of desaturases. Desaturase involvement in changes in membrane fluidity due to changes in dormancy was tested in Chapter 3 (using Sisymbrium officinale) and Chapter 5 (using Arabidopsis thaliana). Here we found that although desaturase activity may change the membrane fluidity or influence the germination/dormancy phenotype, the two are not linked, unless the effects of these enzymes are very local within the seed. Finally, in Chapter 7, we presented a new model in which a membrane anchored dormancy related protein/transcription factor is activated by changes in membrane fluidity. The activated form is transported to the nucleus, where it starts the germination process, which includes changes in metabolism and mobilization of storage reserves.
Seed quality in genetic resources conservation : a case study at the Centre for Genetic Resources, the Netherlands
Groot, S.P.C. ; Groot, E.C. de - \ 2008
Wageningen : Centre for genetic resources (CGN) (Report / Centre for Genetic Resources 2008/11) - 47
zaden - kiemrust - zaadlevensduur - zaadkieming - zaadkwaliteit - zaadveroudering - zaadleeftijd - genenbanken - gewassen - zaad verzamelen - aardappelen - uien - spinazie - slasoorten - erwten - vicia faba - bonen - meloenen - komkommers - tomaten - vlas - graansoorten - akkerbouw - zaadproductie - ex-situ conservering - opslag van zaden - seeds - seed dormancy - seed longevity - seed germination - seed quality - seed aging - seed age - gene banks - crops - seed collection - potatoes - onions - spinach - lettuces - peas - vicia faba - beans - melons - cucumbers - tomatoes - flax - cereals - arable farming - seed production - ex situ conservation - seed storage
This report describes an analysis of the impact of workflow and storage conditions at the Centre for Genetic Resources the Netherlands (CGN) on the quality of seed samples in their genebank collection which is maintained under low temperature and low relative humidity conditions. Emphasis is placed on seed longevity and health.
Kieming van zaad: een nogal ingewikkeld proces, hormonen belangrijk bij ontstaan en doorbreken van kiemrust
Kierkels, T. ; Heuvelink, E. - \ 2006
Onder Glas 3 (2006)12. - p. 48 - 49.
zaadkieming - kiemrust - plantenfysiologie - temperatuur - klimaatfactoren - glastuinbouw - seed germination - seed dormancy - plant physiology - temperature - climatic factors - greenhouse horticulture
Beschrijving van kiemprocessen van groentegewassen (kiemrust, kiemrustdoorbreking, hormonen en kiemrust, fasen van het kiemproces)
Europese bedrijven professionaliseren geconditioneerde stratificatie
Derkx, M.P.M. ; Jensen, M. - \ 2005
De Boomkwekerij 18 (2005)2. - ISSN 0923-2443 - p. 14 - 16.
houtachtige planten als sierplanten - zaden - stratificatie (zaden) - voorkieming - kiemrust - zaadvochtigheid - boomteelt - onderzoeksprojecten - europa - ornamental woody plants - seeds - stratification - pregermination - seed dormancy - seed moisture - arboriculture - research projects - europe
Boomkwekerijen, onderzoeksinstituten en zaadbedrijven uit heel Europa werken samen om het geconditioneerde stratificeren van boomzaden in de vingers te krijgen. Bij veel zaadsoorten lukt dat inmiddels heel goed
Dormancy, germination and emergence of weed seeds, with emphasis on the influence of light : results of a literature survey
Riemens, M.M. ; Scheepens, P.C. ; Weide, R.Y. van der - \ 2004
Wageningen : Plant Research International (Note / Plant Research International 302) - 40
onkruidbestrijding - biologische landbouw - zaadkieming - kiemrust - zaadopkomst - weed control - organic farming - seed germination - seed dormancy - seedling emergence
This note reports the results of an inventory study about the influence of the external factors temperature, light, nitrate, gaseous environment of seeds and moisture on the dormancy, germination and emergence of weed seeds. The inventory was made as a guideline for research aiming at the development of weed control methods that make use of these factors to prevent or stimulate germination of weeds in Dutch organic agriculture. Using the available techniques there is still a notable amount of weeds left in the row that has to be removed by hand. Bottlenecks concerning labour are mainly caused by the need to remove these weeds, especially in slowly growing crops. Focus in this study was on the effects of light on the germination and emergence of weeds (seeds) since this factor is relatively easy to alter in the field and is important for germination of seeds for many species
|Teelthandleiding consumptieaardappelen : pootgoedbehandeling
Veerman, A. - \ 2003
Kennisakker.nl 2003 (2003)15 sept.
solanum tuberosum - aardappelen - teeltsystemen - plantenfysiologie - kieming - kiemrust - groeifactoren - consumptieaardappelen - akkerbouw - teelthandleidingen - potatoes - cropping systems - plant physiology - germination - seed dormancy - growth factors - table potatoes - arable farming - cultivation manuals
In deze teelthandleiding wordt ingegaan op de fysiologie van de knol, factoren die de lengte van de kiemrust bepalen en de kiemgroei beinvloeden. De fysiologische leeftijd van de knol en groeiverloop van het gewas, en de pootgoedbehandeling.
|Teelthandleiding zetmeelaardappelen: pootgoedbehandeling
Veerman, A. - \ 2003
Kennisakker.nl 2003 (2003)15 dec..
pootaardappelen - vermeerderingsmateriaal - voorbehandeling - kiemrust - kiemvorming - kieming - fabrieksaardappelen - akkerbouw - teelthandleidingen - seed potatoes - propagation materials - pretreatment - seed dormancy - nucleation - germination - starch potatoes - arable farming - cultivation manuals
In dit deel van de teelthandleiding zetmeelaardappelen wordt ingegaan op de pootgoedbehandeling bij de teelt van zetmeelaardappelen.
Genetic analysis of seed dormancy and seed composition in Arabidopsis thaliana using natural variation
Bentsink, L. - \ 2002
Wageningen University. Promotor(en): M. Koornneef. - S.l. : S.n. - ISBN 9789058087058 - 159
arabidopsis thaliana - kiemrust - zaden - bladeren - plantensamenstelling - zaadkieming - zaadnarijping - genetische analyse - genetische variatie - genetische regulatie - plantenfysiologie - arabidopsis thaliana - seed dormancy - seeds - leaves - plant composition - seed germination - seed maturation - genetic analysis - genetic variation - genetic regulation - plant physiology
The model plant Arabidopsis thaliana has a broad natural distribution throughout the Northern Hemisphere therefor many different accessions could be collected from natural populations and are available for experimental analysis. These accessions provide an alternative source of genetic variation that can be used to study the function of genes.
The main aim of the work presented in this thesis is to increase the knowledge about the genetic control of seed dormancy. Therefore the natural variation present between two Arabidopsis accessions; Landsberg erecta and Cape Verde Islands has been analysed for this character. This analyses revealed several loci involved in seed dormancy, one of them has been further characterised and fine-mapped. In addition other seed traits that might be related to seed dormancy and germination have been analysed. These traits are seed oligosaccharide content, seed storability and seed phytate and phosphate content.
Seed dormancy and germination
Bentsink, L. ; Koornneef, M. - \ 2002
In: Unknown - p. 1 - 18.
arabidopsis thaliana - kiemrust - zaadkieming - zaadontwikkeling - seed dormancy - seed germination - seed development
Arabidopsis possesses dormancy, as is the case for many other plant species, which is controlled by environmental factors such as light, temperature and time of dry storage as well as by genetic factors. The use of genetics and molecular genetics in Arabidopsis is starting to shed light on some aspects of the mechanism of dormancy and germination by the identification of mutants and genes that control these processes. This review provides an overview of current knowledge of factors and genes controlling seed dormancy and germination in Arabidopsis
Germination and dormancy of single tomato seeds : a study using non-invasive molecular and biophysical techniques
Spoelstra, P. - \ 2002
Wageningen University. Promotor(en): L.H.W. van der Plas; H.W.M. Hilhorst. - S.l. : S.n. - ISBN 9789058086556 - 134
solanum lycopersicum - kiemrust - zaadkieming - zaden - technieken - histonen - solanum lycopersicum - seed dormancy - seed germination - seeds - techniques - histones
Formation , germination and dormancy of seeds are important steps in the life cycle of higher plants. The seed is the generative dispersal unit, which enables plants to spread and survive through periods or seasons of less favourable conditions. In agriculture tomato is an important crop and seed companies go through big efforts to deliver uniformly germinating seed batches. Uniform germination of a seed lot does not often come naturally. Seed to seed variation in timing of germination and also dormancy cause non-uniform germination of seed batches. This variation and dormancy of tomato seeds is the subject of the experimental work presented in this thesis. Several molecular and biophysical techniques have been used to expand our knowledge of tomato seed physiology.
The firefly luciferase-luciferin system has been used in two distinct techniques to study single tomato seeds. A reporter gene construct consisting of a CaMV 35S promoter and the luciferase gene was introduced in tomato by Agrobacterium mediated transformation (Chapter 2). Transgenic seeds were obtained and imbibed in 0.1 mM luciferin solutions. The expression of the luciferase gene was linked with photon emission from the seeds during germination. Luciferase was expressed in a developmental pattern during germination in all germinating seeds. Luciferase expression increased during germination. Although the expression pattern of luciferase was intrinsically linked with the completion of germination, the luciferase activity of a single seed could not be used as a prediction of the time point of visible germination or of the germination rate of a single seed. This was due to the combination of both a time component and an intrinsic variation in the level of expression.
Both primarily and secondarily dormant tomato seeds did not show luciferase activity. This enabled us to distinguish, non destructively, dormant from germinating tomato seeds prior to radicle protrusion and, hence, separation of those seeds for future experiments.
Luciferase was also used to visualize distribution of ATP in sections of tomato seeds during dormancy and germination (Chapter 3). It was shown that not the overall ATP level or concentration of a seed was related to germination or dormancy per se , but merely the localised increase of ATP levels in the radicle. Dormant tomato seeds did not show an increase in the level of ATP in the radicle.
Germination of seeds starts with the uptake of water and finishes by water uptake by the radicle at the initiation of seedling growth. Water uptake by tomato seeds was studied with the use of NMR-imaging (Chapter 4) . Water uptake resulted in an uneven distribution of water over the seed tissues. The endosperm had higher water content during germination. Radicle protrusion was accompanied by an uptake of extra water, thereby stretching the endosperm outward which resulted in rupture of the endosperm cap, which marked the end of germination. In contrast with the commonly adopted model in which seeds take up extra water only after germination, tomato seeds showed this extra water uptake prior to germination.
Linker histones play an important role in the regulation of gene expression by remodelling DNA architecture. Distinct linker histones are thereby under control of different developmental processes in plants. With this in mind we have studied the expression of two different linker histones in tomato, which were originally believed to be under control of either GA or ABA, by the use of reverse-transciptase PCR. ABA and GA are antagonists in the regulation of seed germination and this makes both linker histones excellent candidates to play a role in the regulation of germination and dormancy of tomato seeds (Chapter 5). It was shown that the two different linker histones were differentially expressed in seeds, in relation with dormancy or germination. The linker histones also appeared not to be necessarily under direct control of either GA or ABA. A model is presented in which dormancy and germination are controlled by the linker histones, which, on their turn, are under direct control of phytochrome signal transduction. Expression of the histones may be stimulated or accompanied by ABA or GA.
Geconditioneerde stratificatie opent deuren voor bewaring van zaad
Derkx, R. - \ 2001
De Boomkwekerij 14 (2001)17. - ISSN 0923-2443 - p. 16 - 18.
houtachtige planten als sierplanten - zaden - opslag - stratificatie (zaden) - kiemrust - zaadkieming - plantenvermeerdering - ornamental woody plants - seeds - storage - stratification - seed dormancy - seed germination - propagation
Onderzoek naar de bewaarmogelijkheden van zeven zaadsoorten na een geconditioneerde stratificatie in relatie tot de stratificatieduur
Europees bos- en haagplantsoen pakt samen zaadtraject aan
Derkx, R. - \ 2001
De Boomkwekerij 14 (2001)43. - ISSN 0923-2443 - p. 22 - 23.
plantenvermeerdering - bosbouw - boomkwekerijen - zaden - zaadkieming - zaadbehandeling - stratificatie (zaden) - kiemrust - opslag - bewaartijd - landen van de europese unie - bos- en haagplantsoen - propagation - forestry - forest nurseries - seeds - seed germination - seed treatment - stratification - seed dormancy - storage - storage life - european union countries - woody nursery stock
Kwekers en zaadspecialisten binnen de EU willen in een tweejarig project de hele keten van zaadoogst tot uitzaai van bos en haagplantsoen verbeteren. Het belangrijkste doel is het realiseren van een betere, meer voorspelbare zaadopkomst. Belangrijke items daarbij zijn zaadkwaliteit, betere kiemrustopheffing en bewaring van gestratificeerd zaad
|Wees alert op spruitremming van uw aardappelen
Hak, P. - \ 2000
Aardappelwereld 54 (2000)1. - ISSN 0169-653X - p. 23 - 25.
aardappelen - solanum tuberosum - kiemremmers - kiemremming - opslag - behoud - bestraling - kiemrust - groeivertraging - vegetatieve organen van de plant - potatoes - germination inhibitors - sprout inhibition - storage - preservation - irradiation - seed dormancy - growth retardation - plant vegetative organs
Het voorkomen van kieming bij bewaaraardappelen. Denk daarbij vooral aan: kiembeheersing bij consumptieaardappelen; kiemrust; beheersing van de kiemrust tijdens de bewaring; chemisch remmen van de kieming; natuurlijke kiemremmers
Geconditioneerd stratificeren van boomzaden wint terrein
Derkx, R. - \ 1999
De Boomkwekerij 12 (1999)42. - ISSN 0923-2443 - p. 13 - 15.
zaden - houtachtige planten als sierplanten - kiemrust - zaadkieming - stratificatie (zaden) - kieming - temperatuur - bomen - seeds - ornamental woody plants - seed dormancy - seed germination - stratification - germination - temperature - trees
Verslag van onderzoek op bedrijfsniveau: invloed van geconditioneerd stratificeren bij Acer-, Fraxinus- en Tilia- en Prunus-cultivars op opkomstpercentage
Tilia cordata profiteert van goede condities tijdens stratificatie
Derkx, M.P.M. - \ 1999
De Boomkwekerij 12 (1999)15. - ISSN 0923-2443 - p. 19 - 21.
houtachtige planten als sierplanten - tilia - zaden - kieming - kiemrust - zaadkieming - stratificatie (zaden) - ornamental woody plants - tilia - seeds - germination - seed dormancy - seed germination - stratification
De kieming van Tilia cordata. De juiste tijdsduur van stratificatie, de juiste temperatuur en vochtgehalte van het zaad zorgen voor een snelle kimeing na uitzaai
Geconditioneerd stratificerem verbetert opkomst Acer - soorten
Derkx, R. - \ 1999
De Boomkwekerij 12 (1999)11. - ISSN 0923-2443 - p. 19 - 21.
houtachtige planten als sierplanten - zaden - stratificatie (zaden) - kieming - zaadkieming - kiemrust - temperatuur - ornamental woody plants - seeds - stratification - germination - seed germination - seed dormancy - temperature
Tips voor het stratificeren van Acer platanoides en Acer pseudoplatanus. In de tabellen en figuren gegevens over: 1) uitzaai buiten van Acer platanoides; 2) uitzaai buiten van Acer pseudoplatanus; 3) het effect van de stratificatieduur op de opheffing van de kiemrust van Acer platanoides-zaden; 4) het effect van vochtgehalte van Acer platanoides-zaad op de kieming tijdens en na de stratificatie