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Cisgenic plants are genetically modified plants that do not contain foreign genes. The plants have been enriched with genes from sexually compatible plants. 1,2,3,4,5 The introduced genes are flanked by their native promoters and terminators in natural orientation, and contain their native introns. The Netherlands Commission on Genetic Modification (COGEM) has discussed the safety of cisgenic plants, and has concluded that the risks of cisgenic plants are similar to the risks of conventionally bred plants. However, in view of food and feed safety, the COGEM recommended investigating whether T-DNA borders from Agrobacterium tumefaciens may lead to allergenicity or toxicity.6 When A. tumefaciens is used for genetic modification, so-called T-DNA borders repeats may co-insert with the cisgenes. Remnants of the T-DNA borders are found back as two short DNA sequences of at maximum only three and 22 basepairs, respectively, which flank the cisgene in the cisgenic plant. The COGEM experts are of the opinion that it is very unlikely that these short DNA sequences will lead to a risk, for three reasons. Firstly, it is very unlikely that this border insertion will give rise to a new functional protein. Secondly, the chance is negligibly small that, if a functional protein would be produced, that this protein would lead to an ecological advantage of the plant. Thirdly, the genomes of plants are dynamic, and in nature numerous small or larger rearrangements of the genome occur. Potential risks of insertion of short ‘foreign’ DNA sequences therefore do not exceed the risks of naturally occurring risks or risks 2 of conventional breeding. For these reasons, the very unlikely risks are, according to the COGEM, within the baseline of conventional breeding.7 The COGEM discussed this in a meeting with two experts from RIKILT and SIR, working in the field of feed and food safety. These experts did neither falsify nor confirm the scientific reasoning of the COGEM experts, but instead pr

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Presentation about plant breeding techniques (NPBT)

Presentation about coexistence of GM and non-GM cultivations, consumers' preference.

Presentatie over GG en niet-GG gewassen, consumentenvoorkeuren en manieren om beide gewassen naast elkaar te kunnen telen.

Video recording about breeding and genetics

Video about breeding and genetics

Presentatie over de voor- en nadelen van hybride rassen

Presentatie over regelgeving rondom GG planten, met toelichting.

Background: Crambe abyssinica (crambe) is a non-food oil seed crop. Its seed oil is widely used in the chemical industry because of the high erucic acid content. Furthermore, it is a potential platform for various feedstock oils for industrial uses based on genetic modification. Here, we describe the development of a series of protocols for all steps required in the process of generating genetically modified crambe. Results: Different explant types from crambe seedlings were tested for shoot regeneration using different hormone-combinations. Cotyledonary nodes on basic medium with 0.5 µM NAA and 2.2 µM BAP gave the highest regeneration percentages. For propagation by tissue culture, explants of stems, petioles, leaves and axillary buds of in vitro plantlets were tested using the optimized medium. Axillary buds showed the highest shoot proliferation efficiency. Cotyledonary nodes were used to test the proper concentration of kanamycin for selection of transformation events, and 10 to 25 mg · L-1 were identified as effective. The cotyledonary nodes and cotyledons from 7-day-old seedlings were used in Agrobacterium-mediated transformations with two kinds of selection strategies, shifting or consistent. Using the shifting selection method (10 mg · L-1 kanamycin, 25 mg · L-1, then back to 10 mg · L-1) cotyledonary nodes gave 10% transformation frequency, and cotyledons 4%, while with the consistent method (25 mg · L-1) lower frequencies were found, 1% for cotyledonary nodes and 0% for cotyledons). Later, in vitro plant axillary buds were tried as explants for transformation, however, transformation frequency was low ranging from 0.5 to 2%. Overall, testing six different vectors and two kinds of Agrobacterium strains, the average transformation frequency using the shifting method was 4.4%. Determining T-DNA insertion numbers by Southern blotting showed that approximately 50% of the transgenic lines had a single-copy insertion. Conclusions: Present research revealed the po

BACKGROUND: Our previous study on ripe apples from a progeny of a cross between the apple cultivars 'Prima' and 'Fiesta' showed a hotspot of mQTLs for phenolic compounds at the top of LG16, both in peel and in flesh tissues. In order to find the underlying gene(s) of this mQTL hotspot, we investigated the expression profiles of structural and putative transcription factor genes of the phenylpropanoid and flavonoid pathways during different stages of fruit development in progeny genotypes. RESULTS: Only the structural gene leucoanthocyanidin reductase (MdLAR1) showed a significant correlation between transcript abundance and content of metabolites that mapped on the mQTL hotspot. This gene is located on LG16 in the mQTL hotspot. Progeny that had inherited one or two copies of the dominant MdLAR1 alleles (Mm, MM) showed a 4.4- and 11.8-fold higher expression level of MdLAR1 respectively, compared to the progeny that had inherited the recessive alleles (mm). This higher expression was associated with a four-fold increase of procyanidin dimer II as one representative metabolite that mapped in the mQTL hotspot. Although expression level of several structural genes were correlated with expression of other structural genes and with some MYB and bHLH transcription factor genes, only expression of MdLAR1 was correlated with metabolites that mapped at the mQTL hotspot.MdLAR1 is the only candidate gene that can explain the mQTL for procyanidins and flavan-3-ols. However, mQTLs for other phenylpropanoids such as phenolic esters, dihydrochalcones and flavonols, that appear to map at the same locus, have so far not been considered to be dependent on LAR, as their biosynthesis does not involve LAR activity. An explanation for this phenomenon is discussed. CONCLUSIONS: Transcript abundances and genomic positions indicate that the mQTL hotspot for phenolic compounds at the top of LG16 is controlled by the MdLAR1 gene. The dominant allele of the MdLAR1 gene, causing increased content

Apple scab resistance genes, HcrVf1 and HcrVf2, were isolated including their native promoter, coding and terminator sequences. Two fragment lengths (short and long) of the native gene promoters and the strong apple rubisco gene promoter (PMdRbc) were used for both HcrVf genes to test their effect on expression and phenotype. The scab susceptible cultivar ‘Gala’ was used for plant transformations and after selection of transformants, they were micrografted onto apple seedling rootstocks for scab disease tests. Apple transformants were also tested for HcrVf expression by quantitative RT-PCR (qRTPCR). For HcrVf1 the long native promoter gave significantly higher expression that the short one; in case of HcrVf2 the difference between the two was not significant. The apple rubisco gene promoter proved to give the highest expression of both HcrVf1 and HcrVf2. The top four expanding leaves were used initially for inoculation with monoconidial isolate EU-B05 which belongs to race 1 of V. inaequalis. Later six other V. inaequalis isolates were used to study the resistance spectra of the individual HcrVf genes. The scab disease assays showed that HcrVf1 did not give resistance against any of the isolates tested regardless of the expression level. The HcrVf2 gene appeared to be the only functional gene for resistance against Vf avirulent isolates of V. inaequalis. HcrVf2 did not provide any resistance to Vf virulent strains, even not in case of overexpression. In conclusion, transformants carrying the apple-derived HcrVf2 gene in a cisgenic as well as in an intragenic configuration were able to reach scab resistance levels comparable to the Vf resistant control cultivar obtained by classical breeding, cv. ‘Santana’.

In verband met het onderzoek naar de eventuele gevolgen voor wat betreft de sedimentatie van het Noordelijk Bekken, dat zal ontstaan na voltooing van de bochtafsnijding in de Westerschelde nabij Bath, is in het onderhavige onderzoek een berekeningsmethode ontwikkeld waarmee zand- en slibconcentraties in getijstromen kunnen worden berekend. In het onderzoek zijn een aantal berekeningen uitgevoerd waarmee een indruk, verkregen kan worden van de sedimentatie van slibrijk water dat gedurende de eb het Noordelijk Bekken binnenstroomt via een overlaat die gesitueerd is in het huidige vaarwater boven Bath. Naast bovengenoemde toepassingsmogelijkheid heeft de berekeningsmethode nog een aantal andere toepassings mogelijkheden: 1) het berekenen van instationaire snelheidsvertikalen in estuaria (in getijstromen met een horizontale zout-zoetgradiënt. 2) het berekenen van wrijvingscoëfficiënten in instationaire stromen. 3) het berekenen van instationaire zand- en slibconcentratievertikalen met andere randvoorwaarden aan de bodem dan in het onderhavige onderzoek gebruikt zijn., Hydraulic Engineering, Civil Engineering and Geosciences