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Notification report


General information

Notification Number
B/GB/17/01

Member State to which the notification was sent
United Kingdom

Date of acknowledgement from the Member State Competent Authority
02/02/2017

Title of the Project
Improving late blight (Phytophthora infestans) resistance in potato using resistance genes from wild potato relatives.

Proposed period of release:
01/05/2017 to 30/11/2020

Name of the Institute(s) or Company(ies)
The Sainsbury Laboratory, John Innes Centre
Colney Lane
Norwich, NR4 7UH;


3. Is the same GMPt release planned elsewhere in the Community?
No

Has the same GMPt been notified elsewhere by the same notifier?
No

Genetically modified plant

Complete name of the recipient or parental plant(s)
Common NameFamily NameGenusSpeciesSubspeciesCultivar/breeding line
potatosolanaceaesolanumsolanum tuberosumtuberosumMaris Piper

2. Description of the traits and characteristics which have been introduced or modified, including marker genes and previous modifications:
- Improved resistance to Phytophthora infestans in most of the lines
- Improved resistance to potato cyst nematodes in some of the lines
- Improved tuber quality in some of the lines (i.e., reduced browning and reduced potential for acrylamide formation and blackening upon cooking)
- Resistance to sulfonylureas and imidazolinones due to the selectable marker gene (only used for the in vitro selection of transformed plant cells).


Genetic modification

3. Type of genetic modification:
Insertion;

In case of insertion of genetic material, give the source and intended function of each constituent fragment of the region to be inserted:
Most of the transgenic lines included in this application contain plant resistance (R) genes (Rpi-vnt1.1, Rpi-amr3i and/or Rpi-amr1e), introduced as single R genes or combined as a 3-R-gene stack. Some of the transgenic lines will carry the Oc-I∆D86 cystatin gene and a gene coding for a repellent peptide. The expression of these genes is targeted to the plant root system and confers resistance against potato cyst nematodes (PCN). The stack conferring resistance against PCN has been introduced on its own, or combined with the 3-R-gene stack against late blight, with or without gene-silencing modules that improve tuber quality. These silencing modules are designed to silence the polyphenol oxidase gene Ppo, the asparagine synthetase-1 gene Ast1 and the vacuolar acid invertase gene Vlnv in a tuber-specific manner. Finally, all the transgenic plants proposed for release in this application will also contain the CSR gene which confers resistance to some herbicides (sulfonylureas and imidazolinones). This trait will be used only for the in vitro selection of transgenic lines during tissue culture and these plants remain sensitive to other herbicides.

Details on the constituent fragments of the regions to be inserted (in different combinations) are listed below:

- T-DNA borders (Agrobacterium tumefaciens) for insertion of genetic material into plant chromosome.
- The CSR gene, which is an allele of the acetolactate synthase (ALS) gene from Solanum lycopersicum that confers resistance to sulfonylureas and imidazolinones in plant material. This gene is used as selectable marker gene only for in vitro selection of transformants and is regulated by its endogenous promoter and terminator sequences.
- Resistance gene Rpi-amr3i (Solanum americanum) with endogenous promoter and terminator sequences for improved resistance to P. infestans.
- Resistance gene Rpi-amr1e (Solanum americanum) with endogenous promoter and terminator sequences for improved resistance to P. infestans.
- Resistance gene Rpi-vnt1.1 (Solanum venturii) with endogenous promoter and terminator sequences for improved resistance to P. infestans.
- The Oc-I∆D86 gene, encoding a variant of the rice (Oryza sativa) cysteine proteinase inhibitor Oc-I for resistance to potato cyst nematodes. This gene is under the control of the root-specific regulatory sequences of the Arabidopsis thaliana ARSK1 gene.
- A gene encoding a repellent peptide of synthetic origin for resistance to potato cyst nematodes. The repellent is fused to a signal sequence from the Nicotiana plumbaginifolia calreticulin gene that favours its release from roots. This gene is under the control of the root-specific regulatory sequences of the Arabidopsis thaliana MDK4-20 gene.
- Sense and anti-sense sequences of the Solanum tuberosum vacuolar acid invertase gene (Vlnv) in between convergent tuber-specific promoters of the Solanum tuberosum ADP-glucose pyrophosphorylase (Agp) and granule-bound starch synthase (Gbss) genes.
- Sense and anti-sense sequences of the Solanum tuberosum polyphenol oxidase gene (Ppo) combined with sense and anti-sense sequences of the Solanum tuberosum asparagine synthetase-1 gene (Ast1), both in between convergent tuber-specific promoters of the Solanum tuberosum ADP-glucose pyrophosphorylase (Agp) and granule-bound starch synthase (Gbss) genes.

Terminator sequences included in this application are not related to any technology that prevents seed propagation of plants.


6. Brief description of the method used for the genetic modification:
Plasmid DNA was introduced into the potato lines by Agrobacterium-mediated gene transfer technology. This is standard technology for potato transformation.

7. If the recipient or parental plant is a forest tree species, describe ways and extent of dissemination and specific factors affecting dissemination:
Not applicable.

Experimental Release

1. Purpose of the release:
Since 2001, we have been working towards identifying, mapping and isolating resistance (R) genes from potato that confer resistance against potato late blight (Phytophthora infestans). This research has been publicly funded. The genes identified are potentially valuable weapons in the fight against potato late blight as they confer resistance against many different isolates of this pathogen, including the strains which are currently responsible for major potato losses in the UK and Europe. Thus, there is a need to test these genes in a ‘real’ environment.

Previously, the gene Rpi-vnt1.1 was isolated from the wild potato relative Solanum venturii. This gene was successfully tested in the field after being introduced into Désirée potato plants (Consent 10/R29/01). Recently, two other genes were isolated from the wild potato relative Solanum americanum: Rpi-amr3i and Rpi-amr1e. These three genes have now been transformed into Maris Piper potato, both as single genes or as a three-gene stack. Some of the plants proposed for release have the three-R-gene stack combined with genes conferring resistance against potato cyst nematodes (PCN), with or without gene-silencing modules conferring increased tuber quality. Plants proposed as negative controls in the field trial will only carry the PCN resistance trait.

The aims of the trial are:
1) to demonstrate that the transferred late blight resistance genes offer a valuable method for controlling late blight of potatoes which does not rely on agricultural inputs (pesticides);
2) to confirm that the transferred resistance genes still function in a ‘real life’ situation (i.e. in a field as opposed to a lab/greenhouse);
3) to evaluate the performance of the three-R-gene stack in comparison to the R genes deployed individually;
4) to expose plants containing the newly identified genes to the local populations of late blight to confirm that they are indeed useful;
5) if infection does result in disease, to isolate the corresponding pathogen race.

Even though some of the plants will also carry genes related to nematode resistance and improvement of tuber quality, none of these traits are within the scope of the proposed trial. Those characteristics will be evaluated independently by our collaborators in the project.


2. Geographical location of the site:
The release site will be located at the John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK (Ordnance Survey map grid reference TG 1707).

3. Size of the site (m2):
Approx. 1000 m2

4. Relevant data regarding previous releases carried out with the same GM-plant, if any, specifically related to the potential environmental and human health impacts from the release:
None of the plants included in this application have been previously released. However, similar potato lines carrying some of the genes and/or gene-silencing modules used in this work have been previously tested in the field in the UK or in the US by us or others. Further, some of those lines have been approved for commercialization in the US.

Désirée potato plants carrying Rpi-vnt1.1 were tested in field trials in the UK (Norwich, 2010-2012) and the results of those experiments are in the public domain (Jones et al, 2014). No unexpected effects on humans, animals or the environment were observed and thus all risk management procedures in place were deemed to have been effective. The field trial is currently in the post-trial monitoring phase, and the same procedures followed for that trial are proposed for the release corresponding to this application.

Désirée plants carrying the Oc-I∆D86 cystatin gene or the repellent-coding gene under the control of the root-specific promoters ARSK1 and MDK4-20 respectively, have also been previously tested in field trials in the UK. Results of those trials have been reported in Lilley et al (2004), Kiezebrink and Atkinson (2004) and Green et al (2012). These and other works performed with similar transgenic lines established considerable advantages of this approach to soil micro-organisms relative to nematicide use, with no detrimental effects on non-target organisms and soil health (Cowgill et al, 2002a, 2002b, 2004; Cowgill and Atkinson, 2003; Celis et al, 2004; Kiezebrink and Atkinson, 2004; Green et al, 2012).

Finally, potato plants carrying silencing constructs targeting Ppo, Ast1 or VInv have been described in Rommens et al (2006), Ye et al (2010) and Chawla et al (2012) and have been the subject of field trials in the US. Plants containing these gene-silencing constructs in different combinations have been approved for commercialization or are in the last steps of the deregulation process in that country. In particular, one of those lines carries modules to silence the three genes mentioned above in combination with the late blight resistance gene Rpi-vnt1 included in this application.


Environmental Impact and Risk Management

Summary of the potential environmental impact from the release of the GMPts:
Neither the resistance genes or gene-silencing modules nor the selectable marker gene confer characteristics to the GM potato that would increase the competitiveness of plants containing the genes in unmanaged ecosystems. Neither would the introduced genes enable plants carrying them to out-compete plants of similar type for space. None of the transferred genes are anticipated to affect pollen production and fertility, seed dispersal or frost tolerance. Seeds and tubers, which might be spread outside cultivated fields, would have no competitive advantage in this environment. Potatoes are not persistent outside the agricultural environment and feral potato plants do not generally occur in the UK.

Through the measures that are taken during the release, distance from or absence of conventionally cultivated potatoes or wild species, the possibility of any gene transfer can be virtually ruled out. Even in the very improbable event that pollen was to be transferred to genetically unmodified potato plants, no consequences are to be expected, since potato propagation conventionally takes place via tubers and not via seeds.

Most of the lines included in this application carry late blight resistance (R) genes. Non-transgenic potato plants also contain many R genes, which are active against a wide range of potential pathogens. Many conventional potato varieties also contain additional R genes against P. infestans that have been introgressed from wild Solanum species. An intended effect of the introduced trait is increased survivability of the genetically modified potatoes exposed to P. infestans. This possible selective advantage, however, is of importance only in the agricultural field, and will not otherwise improve the survivability in the surrounding environment.

Some of the transgenic lines included in this application will carry genes coding for a cystatin and for a repellent peptide. The expression of these genes is targeted to the plant root system and confers resistance against potato cyst nematodes (PCN). Cystatins are present in many foods, e.g. rice seeds, maize kernels and chicken egg white, and the repellent to be used is not lethal to animals, but merely prevents plant parasitic species from invading roots. Resistance to PCN is not a characteristic that would enhance the invasiveness of potatoes. Further, there’s no evidence of PCN contamination in the soil of our experimental field as well as no evidence that PCN limit the distribution or abundance of wild Solanaceae in the UK.

The resistance traits to be expressed are predicted to affect only the target pathogens, Phytophthora infestans and PCN (if present). The expected environmental impact is negligible and will reduce the level of other agricultural inputs such as use of fungicides or nematicides to control late blight or potato cyst nematodes in potato crops.

The gene-silencing modules present in some of the plants are designed to modify tuber quality traits that are important in post-harvest management and processing of the potato tubers. They are not expected to affect the fitness of the plants in field conditions.

All the plasmids used to generate the plants included in this application carry an allele of the tomato acetolactate synthase (ALS) gene encoding a variant of the ALS enzyme that is resistant to inhibition by sulfonylureas and imidazolinones. Resistance to ALS-inhibiting herbicides is present in several commercially-available crops. This trait will be used only for the in vitro selection of transgenic lines during tissue culture. The plants remain sensitive to other herbicides such as glyphosate or glufosinate, which could readily be used to eliminate them in the field. In addition, sulfonylureas and imidazolinones will not be used in the context of this trial, so no selective advantage will be conferred to this plants.

Finally, in the unlikely event of backbone integration, no detrimental effect is expected from any of the elements in the vector backbone and no other emergent advantages or disadvantages are expected from the proposed combinations of genes and traits.

The interactions of the genetically modified potato lines with non-target organisms and the effects resulting from this will be comparable to those of conventional potato varieties. Due to a reduced need for fungal treatments, an increase in the populations of those non-target organisms that respond to fungal treatments might be expected. Similarly, the nematode resistance trait has been previously tested in the field. Works performed with similar transgenic lines established considerable advantages of this approach to soil micro-organisms relative to nematicide use, with no detrimental effects on non-target organisms and soil health.

No toxic or allergenic effects are expected from any of the additional proteins expressed in the transgenic lines proposed for release. Measures which are taken under current release practice will both protect the trial against damage by wild animals, and also ensure that seed stock and plant material are harvested, transported and disposed in a way that minimises or prevents contact with people or animals. No effects on biogeochemical processes are expected, other than those that apply also to non-genetically modified potatoes.


Brief description of any measures taken for the management of risks:
An isolation distance of 20 m to other potato varieties will be observed.

The release site will be visited by trained laboratory personnel at no less than weekly intervals during May-November (the potato growing season) of each year of the trial. Visits will usually occur more frequently. Any unexpected occurrences that could potentially result in adverse environmental effects or the possibility of adverse effects on human health will be notified to the national inspectorate immediately. Should the need arise to terminate the release at any point the emergency plans detailed below will be followed.

At the end of each season, all harvested material (plant tops and tubers) will be placed in sealed bags or containers and removed from site to an authorised waste disposal facility. Disposal will be carried out by incineration through our contractor SRCL. The plot will be left fallow and monitored for groundkeepers during the remainder of the year. Any volunteers identified will be immediately destroyed either by application of a systemic broadleaf herbicide or by hand pulling plants and digging out tubers/root systems. These will then be autoclaved within the Sainsbury Laboratory. The monitoring of the plot for groundkeepers will be continued at monthly intervals for the duration of the four-year trial by walking the trial site.

Following completion of the four-year trial the release site will remain fallow to enable easy identification of volunteers. The site will be inspected monthly between April and November (the growing season of potato) and any volunteers identified will be immediately destroyed either by hand pulling plants and digging out tubers/root systems followed by autoclaving within the Sainsbury Laboratory. If volunteers are found at the end of the two-year period, DEFRA recommendations will be followed for the management of the release site. Both raw data and reports of inspections of groundkeepers and volunteers will be maintained and provided to DEFRA. The cultivation of the release site after the monitoring programme has concluded will be according to local crop rotation practice for potatoes.

Emergency procedures: At any time point post planting, should the release need to be terminated, any plant material will be sprayed with an appropriate systemic broadleaf herbicide and tubers dug up by fork and hand and transferred to an authorised waste facility for disposal by deep burying or incineration. Should the release site be subject to vandalism, care will be taken to ensure that all uprooted plant material within and outside of the trial site is identified and destroyed accordingly as described above.


Summary of foreseen field trial studies focused to gain new data on environmental and human health impact from the release:
Not applicable.

Final report
-

European Commission administrative information

Consent given by the Member State Competent Authority:
Yes
27/04/2017 00:00:00
Remarks: