Botrytisvoorspeller in gerbera: Praktijkervaringen met het gebruik van de Botrytisvoorspeller van Wageningen UR Glastuinbouw via LetsGrow.com
Helm, F.P.M. van der; Visser, P.H.B. de - \ 2012
Bleiswijk : Wageningen UR Glastuinbouw (Rapporten GTB 1208) - 54
botrytis - plantenziekteverwekkende schimmels - groeimodellen - gerbera - sierteelt - gewasbescherming - gebruikswaarde - computertechnieken - botrytis - plant pathogenic fungi - growth models - gerbera - ornamental horticulture - plant protection - use value - computer techniques
In het project parapluplan Gerbera is een Botrytisvoorspeller ontwikkeld. Dit model kan op de PC van de kweker draaien, maar dit vereist een installatieprocedure die een grote belemmering blijkt voor toepassen van de voorspeller. Kwekers hebben in een Pilotperiode van een half jaar gestest of de weergave van het model in LetsGrow.com een eenvoudiger alternatief is. LetsGrow.com gebruikt de informatie uit de klimaatcomputer dan automatisch voor het draaien van het model. Gedurende de pilotperiode is weinig Botrytis voorgekomen in de kas. Als dit wel het geval was, dan is dit ook berekend/voorspeld. De voorspelling vooraf bleek lastig te interpreteren. Na uitleg over de grafieken in de tussentijdse bijeenkomst realiseerde de kwekers zich de betekenis van de lijnen beter. Kwekers blijken al snel een veilige strategie te voeren, met hoger energieverbruik dan strict noodzakelijk tot gevolg. Aanbevelingen voor verbetering zijn de voorspelling en de realisatie te combineren zodat van het verleden geleerd kan worden voor de toekomst. Beter begrip van het model en de gevolgen van klimaatinstellingen voor de voorspelling, kan leiden tot een klimaat regeling met lager energieverbruik. Voor de kwekers is het wenselijk dat een bandbreedte van gevoeligheid van het model is in te stellen, zodat zij dit aan hun eigen situatie kunnen tunen. Ten slotte zou een SMS bij hoog infectierisico voor de telers gewenst zijn, omdat zij niet elke dag (kunnen) kijken. De waarde van de Botrytisvoorspeller was voor de deelnemers van de pilotgroep groot genoeg om na de pilotfase verder te gaan tegen betaling. Abstract A predcition model for Botrytis in Gerbera is developped by Wageningen UR greenhouse horticulture. The installation of the software and separate interface from regular climate control evaluation have appeared to be tresholds for adapting the model in everyday practice. A pilotgroup of 10 growers have used the digital platform of LetsGrow.com for data exchange and consulting the model in combination with regular climate control evaluation. Little incidence of Botrytis has occurred during the pilotperiod, although climate was favourable for Botrytis at certain periods during the pilot. One case of Botrytis occurred and was predicted by the model. The interpretation of the data and figures appeared to be more complex than expected. Only after presentation of interpretation of the graphs growers realised how to translate the information to their situation and climate control. Growers tend to use the model to be on the safe side, however it could results in higher use of energy than needed. Growers would like to be able to adjust the sensitivity of the model to tune the model to their specific situation. Also an SMS service when risks are high would is expected to be helpful. Growers still did not use the model on a daily basis, although tresholds were lower. The value was high enough for growers of the pilot to continue using the model and pay for it after the pilotperiod was over.
RNA interference silencing of chalcone synthase, the first step in the flavonoid biosynthesis pathway, leads to parthenocarpic tomato fruits
Schijlen, E.G.W.M. ; Vos, C.H. de; Martens, S. ; Jonker, H.H. ; Rosin, F.M.A. ; Molthoff, J.W. ; Tikunov, Y.M. ; Angenent, G.C. ; Tunen, A.J. van; Bovy, A.G. - \ 2007
Plant Physiology 144 (2007)3. - ISSN 0032-0889 - p. 1520 - 1530.
transcription factor - male-sterility - arabidopsis-thaliana - male-fertility - flower color - tube growth - gene - pollen - petunia - expression
Parthenocarpy, the formation of seedless fruits in the absence of functional fertilization, is a desirable trait for several important crop plants, including tomato (Solanum lycopersicum). Seedless fruits can be of great value for consumers, the processing industry, and breeding companies. In this article, we propose a novel strategy to obtain parthenocarpic tomatoes by down-regulation of the flavonoid biosynthesis pathway using RNA interference (RNAi)-mediated suppression of chalcone synthase (CHS), the first gene in the flavonoid pathway. In CHS RNAi plants, total flavonoid levels, transcript levels of both Chs1 and Chs2, as well as CHS enzyme activity were reduced by up to a few percent of the corresponding wild-type values. Surprisingly, all strong Chs-silenced tomato lines developed parthenocarpic fruits. Although a relation between flavonoids and parthenocarpic fruit development has never been described, it is well known that flavonoids are essential for pollen development and pollen tube growth and, hence, play an essential role in plant reproduction. The observed parthenocarpic fruit development appeared to be pollination dependent, and Chs RNAi fruits displayed impaired pollen tube growth. Our results lead to novel insight in the mechanisms underlying parthenocarpic fruit development. The potential of this technology for applications in plant breeding and biotechnology will be discussed.
Genetic engineering of flavonoid biosynthesis in tomato
Schijlen, E.G.W.M. - \ 2007
University of Amsterdam. Promotor(en): A.J. van Tunen, co-promotor(en): Arnaud Bovy. - Amsterdam : - 160
genetische modificatie - biosynthese - flavonoïden - tomaten - solanum lycopersicum - genetic engineering - biosynthesis - flavonoids - tomatoes
Planten beschikken over een enorme capaciteit om een breed scala aan secundaire metabolieten te produceren waarmee ze kunnen reageren op hun continu veranderende omgeving. Flavonoïden, een van de meest voorkomende soort secundaire metabolieten, zijn laagmoleculaire stoffen die van nature in vrijwel alle planten voorkomen. Ze zijn bij uiteenlopende natuurlijke processen betrokken. Zo ontstaat bijvoorbeeld de rode, blauwe en paarse kleur van veel bloemen door de aanwezigheid van anthocyanen, een specifieke klasse van flavonoïdpigmenten. Ook rijpe vruchten danken hun kleur vaak aan deze klasse van flavonoïden. Daarnaast spelen flavonoïden een rol bij processen zoals bescherming van planten tegen schadelijke UV-straling, afweer tegen infecties, pollenvorming en fertiliteit. Omdat flavonoïden wijdverspreid voorkomen in het plantenrijk, vormen deze stoffen een permanent onderdeel van ons plantaardig voedsel. Een deel van de gezondheidsbevorderende effecten van groenten en fruit wordt toegeschreven aan de aanwezigheid van bepaalde flavonoïden. Hoewel flavonoïden in vrijwel alle planten voorkomen, zijn sommige klassen specifiek voor een bepaalde plantensoort, terwijl deze ondervertegenwoordigd of geheel afwezig kunnen zijn in andere plantensoorten. Vanuit dit oogpunt kan het wenselijk zijn om te selecteren voor gewassen met bepaalde (hoeveelheden van) flavonoïden, dan wel de samenstelling daarvan aan te passen. Onderzoek naar de mogelijkheden om de productie van flavonoïden in planten te veranderen wordt veelal uitgevoerd om de aantrekkelijkheid van sierteeltgewassen óf de voedingswaarde van bepaalde gewassen te verhogen. Elio Schijlen onderzocht de genetische modificatie van de biosyntheseroute van flavonoïden in tomaat. Hiermee wil hij meer inzicht geven in de endogene flavonoïdbiosynthese én de mogelijkheden onderzoeken om nieuwe flavonoïden te produceren die van nature niet voorkomen in tomaten.
Promoter activity of a putative pollen monosaccharide transporter in Petunia hybrida and characterisation of a transposon insertion mutant
Garrido, D. ; Busscher-Lange, J. ; Tunen, A.J. van - \ 2006
Protoplasma 228 (2006)1-3. - ISSN 0033-183X - p. 3 - 11.
male-sterility - heterologous expression - arabidopsis-thaliana - beta-glucuronidase - h+-cotransporter - nicotiana-alata - tube growth - gene family - invertase - plants
For the growth of the male reproductive cells of plants, the pollen, the presence of sufficient sucrose or monosaccharides is of vital importance. From Petunia hybrida a pollen-specific putative monosaccharide transporter designated PMT1 (for petunia monosaccharide transporter) has been identified previously. The present work provides an in-depth analysis and characterisation of PMT1 in the context of pollen development with the GUS reporter gene and an insertion mutant. The promoter of the pollen-specific putative PMT1 gene has been isolated by inverse PCR and sequenced. Analysis of plants transformed with the promoter-GUS fusion confirmed the specificity of this gene, belonging to the late pollen-specific expressed genes. GUS activity was detected even after 24 h of in vitro pollen germination, at the pollen tube tip. To elucidate the importance of PMT1 for gametophyte development and fertilisation, we isolated a mutant plant containing a transposon insertion in the PMT1 gene by the dTph1 transposon-tagging PCR-based assay. The PMT1 mutant contained a dTph1 insertion in position 1474 bp of the transcribing part of the gene, before the last two transmembrane-spanning domains. Analysis of the progeny of the heterozygous mutant after selfing revealed no alterations in pollen viability and fertility. Mature pollen grains of a plant homozygous for the transposon insertion were able to germinate in vitro in a medium containing sucrose, glucose, or fructose, which indicates that PMT1 is not essential for pollen survival. Several explanations for these results are discussed in the present work.
Pathway engineering for healthy phytochemicals leading to the production of novel flavonoids in tomato fruit
Schijlen, E.G.W.M. ; Vos, C.H. de; Jonker, H.H. ; Broeck, H.C. van den; Molthoff, J.W. ; Tunen, A.J. van; Martens, S. ; Bovy, A.G. - \ 2006
Plant Biotechnology Journal 4 (2006)4. - ISSN 1467-7644 - p. 433 - 444.
signal-transduction pathways - stilbene synthase gene - carcinoma cell-lines - heart-disease - biosynthetic-pathway - antioxidant activity - dietary flavonoids - petunia-hybrida - french paradox - male-sterility
Flavonoids are a large family of plant polyphenolic secondary metabolites. Although they are widespread throughout the plant kingdom, some flavonoid classes are specific for only a few plant species. Due to their presumed health benefits there is growing interest in the development of food crops with tailor-made levels and composition of flavonoids, designed to exert an optimal biological effect. In order to explore the possibilities of flavonoid engineering in tomato fruits, we have targeted this pathway towards classes of potentially healthy flavonoids which are novel for tomato. Using structural flavonoid genes (encoding stilbene synthase, chalcone synthase, chalcone reductase, chalcone isomerase and flavone synthase) from different plant sources, we were able to produce transgenic tomatoes accumulating new phytochemicals. Biochemical analysis showed that the fruit peel contained high levels of stilbenes (resveratrol and piceid), deoxychalcones (butein and isoliquiritigenin), flavones (luteolin-7-glucoside and luteolin aglycon) and flavonols (quercetin glycosides and kaempferol glycosides). Using an online high-performance liquid chromatography (HPLC) antioxidant detection system, we demonstrated that, due to the presence of the novel flavonoids, the transgenic tomato fruits displayed altered antioxidant profiles. In addition, total antioxidant capacity of tomato fruit peel with high levels of flavones and flavonols increased more than threefold. These results on genetic engineering of flavonoids in tomato fruit demonstrate the possibilities to change the levels and composition of health-related polyphenols in a crop plant and provide more insight in the genetic and biochemical regulation of the flavonoid pathway within this worldwide important vegetable.
Modification of flavonoid biosynthesis in crop plants
Schijlen, E.G.W.M. ; Vos, C.H. de; Tunen, A.J. van; Bovy, A.G. - \ 2004
Phytochemistry 65 (2004)19. - ISSN 0031-9422 - p. 2631 - 2648.
stilbene synthase gene - signal-transduction pathways - lc regulatory gene - vitis-vinifera l. - flower color - chalcone synthase - anthocyanin biosynthesis - petunia-hybrida - male-sterility - maize lc
Flavonoids comprise the most common group of polyphenolic plant secondary metabolites. In plants, flavonoids play an important role in biological processes. Beside their function as pigments in flowers and fruits, to attract pollinators and seed dispersers, flavonoids are involved in UV-scavenging, fertility and disease resistance. Since they are present in a wide range of fruits and vegetables, flavonoids form an integral part of the human diet. Currently there is broad interest in the effects of dietary polyphenols on human health. In addition to the potent antioxidant activity of many of these compounds in vitro, an inverse correlation between the intake of certain polyphenols and the risk of cardiovascular disease, cancer and other age related diseases has been observed in epidemiological studies. The potential nutritional effects of these molecules make them an attractive target for genetic engineering strategies aimed at producing plants with increased nutritional value. This review describes the current knowledge of the molecular regulation of the flavonoid pathway and the state of the art with respect to metabolic engineering of this pathway in crop plants. Keywords: Flavonoids; Genetic modification; Crop; Plant species
|Flavonoid pathway engineering for improved food quality
Schijlen, E.G.W.M. ; Vos, C.H. de; Jonker, H.H. ; Molthoff, J.W. ; Tunen, A.J. van; Bovy, A.G. - \ 2004
In: Book of abstracts of the 10th Netherlands Biotechnology Congress, Ede, The Netherlands, 11-12 March 2004. - - p. 88 - 88.
The use of floral homeotic mutants as a novel way to obtain durable resistance to insect pests
Kater, M.M. ; Franken, J. ; Inggamer, H. ; Gretenkort, M. ; Tunen, A.J. van; Mollema, C. ; Angenent, G.C. - \ 2003
Plant Biotechnology Journal 1 (2003)2. - ISSN 1467-7644 - p. 123 - 127.
mads box gene - arabidopsis-thaliana - frankliniella-occidentalis - life-history - cucumber - plants - thripidae - petunia
We have developed a novel strategy for the introduction of durable insect resistance in crops. This strategy was based on intervention in the natural relationship between plants and insects. For many insects, including pests such as thrips (Frankliniella occidentalis), the flower is an important factor in their life cycle, serving either as a food source or as a place for mating. The insects are attracted to the flower by scent, which is mainly produced by the petals, and by the bright colour of these floral organs. We therefore anticipated that removal or changing the identity of the petals would significantly reduce the attractiveness of the flower to thrips. To test this hypothesis, we used cucumber as a model species because most modern varieties are parthenocarpic, in which the fruit develops without fertilization. The cucumber mutant green petals, in which the petals are homeotically transformed into green sepals, was particularly useful for this study. The susceptibility of the cucumber plants to damage by thrips was determined by recording thrip numbers and by measuring leaf damage. Large differences were observed when greenhouse compartments with either wild-type or green petal mutant plants were compared. The rate of population growth of the insects on the mutant plants was significantly reduced and the leaves were almost undamaged. These results demonstrate that alterations in the structure of flowers may interfere with the life cycle of insects, providing the means for a novel and natural strategy for obtaining insect resistance.
Domain swapping of Citrus limon monoterpene synthases: impact on enzymatic activity and product specifity.
Tamer, M.K. el; Lucker, J. ; Bosch, D. ; Verhoeven, H.A. ; Verstappen, F.W.A. ; Schwab, W. ; Tunen, A.J. van; Voragen, A.G.J. ; Maagd, R.A. de; Bouwmeester, H.J. - \ 2003
Archives of Biochemistry and Biophysics 411 (2003). - ISSN 0003-9861 - p. 196 - 203.
site-directed mutagenesis - 5-epi-aristolochene synthase - trichodiene synthase - linalool synthase - germacrene-a - biosynthesis - expression - biology
Monoterpene cyclases are the key enzymes in the monoterpene biosynthetic pathway, as they catalyze the cyclization of the ubiquitous geranyl diphosphate (GDP) to the specific monoterpene skeletons. From Citrus limon, four monoterpene synthase-encoding cDNAs for a P-pinene synthase named Cl(-)betaPINS, a gamma-terpinene synthase named ClgammaTS, and two limonene synthases named Cl(+)LIMS1 and Cl(+)LIMS2 were recently isolated [J. Lucker et al., Eur. J. Biochem. 269 (2002) 3160]. The aim of our work in this study was to identify domains within these monoterpene synthase enzymes determining the product specificity. Domain swapping experiments between Cl(-)betaPINS and ClgammaTS and between Cl(+)LIMS2 and ClyTS were conducted. We found that within the C-terminal domain of these monoterpene synthases, a region comprising 200 amino acids, of which 41 are different between Cl(-)betaPINS and ClgammaTS, determines the specificity for the formation of P-pinene or gamma-terpinene, respectively, while another region localized further downstream is required for a chimeric enzyme to yield products in the same ratio as in the wild-type ClgammaTS. For Cl(+)LIMS2, the two domains together appear to be sufficient for its enzyme specificity, but many chimeras were inactive probably due to the low homology with ClyTS. Molecular modeling was used to further pinpoint the amino acids responsible for the differences in product specificity of ClyTS and Cl(-)betaPINS. (C) 2003 Elsevier Science (USA). All rights reserved.
Regulation of floral scent production in petunia revealed by targeted metabolomics
Verdonk, J.C. ; Vos, C.H. de; Verhoeven, H.A. ; Haring, M.A. ; Tunen, A.J. van; Schuurink, R.C. - \ 2003
Phytochemistry 62 (2003). - ISSN 0031-9422 - p. 997 - 1008.
solid-phase microextraction - snapdragon flowers - linalool synthase - rosa-hybrida - in-situ - emission - volatiles - biosynthesis - expression - gene
Petunia hybrida line W115 (Mitchell) has large white flowers that produce a pleasant fragrance. By applying solid phase micro extraction (SPME) techniques coupled to GC-MS analysis, volatile emission was monitored in vivo using a targeted metabolomics approach. Mature flowers released predominantly benzenoid compounds of which benzaldehyde, phenylacetaldehyde, methylbenzoate, phenylethylalcohol, iso-eugenol and benzylbenzoate were most abundant. This emission had a circadian rhythm reaching its maximum at dusk. During petal limb expansion two sesquiterpenes were emitted by the petunia flowers, tentatively identified as germacrene D and cadina-3,9-diene. In vitro analysis showed that the petal limbs and stigma were the main producers of the benzenoids and sesquiterpenes, respectively. Moreover, comparison of in vivo and in vitro analysis indicated that volatiles were not stored during periods of low emission but rather were synthesized de novo. DNA-microarray analysis revealed that genes of the pathways leading to the production of volatile benzenoids were upregulated late during the day, preceding the increase of volatile emission. RNA-gel blot analyses confirmed that the levels of phenylalanine ammonia lyase (PAL) and S-adenosyl methionine (SAM) synthase transcripts increased towards the evening. Our results suggest that the circadian production of volatile benzenoids in petunia W115 is, at least partly, regulated at the transcript level.
High-Flavonol Tomatoes Through Heterologous Expression of the Maize Transcription Factor Genes LC and C1
Bovy, A. ; Vos, R. de; Kemper, M. ; Schijlen, E. ; Almenar Pertejo, M. ; Muir, S. ; Collins, G. ; Robinson, S. ; Verhoeyen, M. ; Hughes, S. ; Santos-Buelga, C. ; Tunen, A. van - \ 2002
The Plant Cell 14 (2002). - ISSN 1040-4651 - p. 2509 - 2526.
Flavonoids are a group of polyphenolic plant secondary metabolites important for plant biology and human nutrition. In particular flavonols are potent antioxidants, and their dietary intake is correlated with a reduced risk of cardiovascular diseases. Tomato fruit contain only in their peel small amounts of flavonoids, mainly naringenin chalcone and the flavonol rutin, a quercetin glycoside. To increase flavonoid levels in tomato, we expressed the maize transcription factor genes LC and C1 in the fruit of genetically modified tomato plants. Expression of both genes was required and sufficient to upregulate the flavonoid pathway in tomato fruit flesh, a tissue that normally does not produce any flavonoids. These fruit accumulated high levels of the flavonol kaempferol and, to a lesser extent, the flavanone naringenin in their flesh. All flavonoids detected were present as glycosides. Anthocyanins, previously reported to accumulate upon LC expression in several plant species, were present in LC/C1 tomato leaves but could not be detected in ripe LC/C1 fruit. RNA expression analysis of ripening fruit revealed that, with the exception of chalcone isomerase, all of the structural genes required for the production of kaempferol-type flavonols and pelargonidin-type anthocyanins were induced strongly by the LC/C1 transcription factors. Expression of the genes encoding flavanone-3'-hydroxylase and flavanone-3'5'-hydroxylase, which are required for the modification of B-ring hydroxylation patterns, was not affected by LC/C1. Comparison of flavonoid profiles and gene expression data between tomato leaves and fruit indicates that the absence of anthocyanins in LC/C1 fruit is attributable primarily to an insufficient expression of the gene encoding flavanone-3'5'-hydroxylase, in combination with a strong preference of the tomato dihydroflavonol reductase enzyme to use the flavanone-3'5'-hydroxylase reaction product dihydromyricetin as a substrate.
Overexpression of petunia chalcone isomerase in tomato results in fruit containing increased levels of flavonols
Muir, S.R. ; Collins, G.J. ; Robinson, S. ; Hughes, S.G. ; Bovy, A.G. ; Vos, C.H.R. de; Tunen, A.J. van; Verhoeven, M.E. - \ 2001
Nature Biotechnology 19 (2001). - ISSN 1087-0156 - p. 470 - 474.
Tomatoes are an excellent source of the carotenoid lycopene, a compound that is thought to be protective against prostate cancer. They also contain small amounts of flavonoids in their peel (|[sim]|5–10 mg/kg fresh weight), mainly naringenin chalcone and the flavonol rutin, a quercetin glycoside. Flavonols are very potent antioxidants, and an increasing body of epidemiological data suggests that high flavonoid intake is correlated with a decreased risk for cardiovascular disease. We have upregulated flavonol biosynthesis in the tomato in order to generate fruit with increased antioxidant capacity and a wider range of potential health benefit properties. This involved transformation of tomato with the Petunia chi-a gene encoding chalcone isomerase. Resulting transgenic tomato lines produced an increase of up to 78 fold in fruit peel flavonols, mainly due to an accumulation of rutin. No gross phenotypical differences were observed between high-flavonol transgenic and control lines. The phenotype segregated with the transgene and demonstrated a stable inheritance pattern over four subsequent generations tested thus far. Whole-fruit flavonol levels in the best of these lines are similar to those found in onions, a crop with naturally high levels of flavonol compounds. Processing of high-flavonol tomatoes demonstrated that 65% of flavonols present in the fresh fruit were retained in the processed paste, supporting their potential as raw materials for tomato-based functional food products.
The application of DNA microarrays in gene expression analysis
Hal, N.L.W. van; Vorst, O. ; Houwelingen, A.M.M.L. van; Kok, E.J. ; Peijnenburg, A.A.C.M. ; Aharoni, A. ; Tunen, A.J. van; Keijer, J. - \ 2000
Journal of Biotechnology 78 (2000)3. - ISSN 0168-1656 - p. 271 - 280.
DNA microarray technology is a new and powerful technology that will substantially increase the speed of molecular biological research. This paper gives a survey of DNA microarray technology and its use in gene expression studies. The technical aspects and their potential improvements are discussed. These comprise array manufacturing and design, array hybridisation, scanning, and data handling. Furthermore, it is discussed how DNA microarrays can be applied in the working fields of: safety, functionality and health of food and gene discovery and pathway engineering in plants.
|Identification of the SAAT gene involved in strawberry flavor biogenesis by use of DNA micro-arrays
Aharoni, A. ; Keizer, L.C.P. ; Bouwmeester, H.J. ; Sun, Z. ; Alvarez-Huerta, M. ; Verhoeven, H.A. ; Blaas, J. ; Houwelingen, A.M.M.L. van; Vos, R.C.H. de; Voet, H. van der; Jansen, R.C. ; Guis, M. ; Davis, R.W. ; Schena, M. ; Tunen, A.J. van; O'Connel, A.P. - \ 2000
The Plant Cell 12 (2000). - ISSN 1040-4651 - p. 647 - 661.
Methods and composition for modulating flavonoid content (II)
Verhoeyen, M. ; Hughes, S. ; Muir, S. ; Vos, R. de; Bovy, A. ; Tunen, A.J. van - \ 1999
Octrooinummer: WO0004175, gepubliceerd: 1999.
A method for manipulating the production of flavonoids in tomatoes by manipulating gene activity in the flavonoid biosynthetic pathway by expressing genes encoding chalcone isomerase, compositions for use in such a method and tomato plants having altered flavonoid levels are disclosed.
Pollen tubes of flavonol-deficient Petunia show striking alterations in wall structure leading to tube disruption
Derksen, J. ; Wezel, R. van; Knuiman, B. ; Ylstra, B. ; Tunen, A.J. van - \ 1999
Planta 207 (1999). - ISSN 0032-0935 - p. 575 - 581.
|High level fructan accumulation in a transgenic beet
Sévenier, R. ; Hall, R.D. ; Meer, I.M. van der; Hakkert, J.C. ; Tunen, A.J. van; Koops, A.J. - \ 1998
Nature Biotechnology 16 (1998). - ISSN 1087-0156 - p. 843 - 846.
|Cloning of the fructan biosynthesis pathways of Jerusalem artichoke; plant fructan genes are members of the invertase gene family
Meer, I.M. van der; Koops, A.J. ; Hakkert, J.C. ; Tunen, A.J. van - \ 1998
The Plant Journal 15 (1998). - ISSN 0960-7412 - p. 489 - 500.
|Genetic modification of flavour and fragrance production in plants
Verhoeven, H.A. ; Aharoni, A. ; Wein, M. ; Blaas, J. ; Bouwer, R. ; Tunen, A.J. van - \ 1998
In: Natural product analysis / Schreier, P., Herderich, M., Humpf, H.U., Schwab, W., - p. 311 - 312.
The use of an automated cell tracking system to identify specific cell types competent for regeneration and transformation
Krens, F.A. ; Verhoeven, H.A. ; Tunen, A.J. van; Hall, R.D. - \ 1998
In Vitro Cellular and Developmental Biology. Plant 34 (1998). - ISSN 1054-5476 - p. 81 - 86.