3. Blog: Cisgenic apples-an example

Blog 3: Cisgenic apples-an example

Questions for the third blog entry:

1. As they are using genes from apples only – why not produce these plants using classical breeding methods?

2. Is apple scab a major concern for Swiss apple producers? (reference and numbers please)

3. In your opinion, would Swiss farmers grow these plants?

4. Would Swiss consumers buy these apples?

5. These plants are now tested in a field trial in Reckenholz. Think of 2-3 questions you would like to ask the scientists performing these tests.

1. Breeding a new apple cultivar in a classical way is always vegetative. Thereby the genotype of all apple trees of the same cultivar is identical. To bring new genes, e.g. resistance to apple scab, into the genome, cross-breeding with e.g. a wild apple cultivar is a possibility. Through the long juvenile stage of apple trees, this method is very protracted and lasts at least 20-25 years. Moreover through the first cross breeding step the apple cultivar is not the same any more. [4]
Nevertheless different apple cultivars were bred in this way over the last decades. But all this resistant cultivars have different gustatory attributes and are less palatable. [1] 

Figure 1: The nile stalong-lasting cross-breeding process to get a resistant apple
cultivar because of the long juvege. [1]

Furthermore through cross breeding also unwanted genes pass to the next generation, which then have to be eliminated through back-crossing processes. [2]

In the mentioned research paper, the scientists of ETH Zürich wanted to bring only the resistance encoding gene “HcrVf2” with its regulatory sequences into the new apple plant. To save time and probably to keep the gustatory attributes of the apple cultivar “Gala”, the scientists used Agrobacterium mediated transformation to bring the selected apple gene into the genome of the apple tree. [3]

2. Apple scab is the most important fungal disease for apple trees and it is widespread all over the world. [1] [4]
I did not found specific numbers for the situation in Switzerland, but on pflanzen-forschung-ethik.de it is written, that especially “Gala” and “Jonagold”, which are commonly apple cultivars in Switzerland [5], are highly susceptible for the fungal pathogen Venturia inaequalis. [4] In conventional apple production up to 16 treatments with fungicides are necessary in one season. In organic farming copper and sulphuric compounds are used. [4]

Alternatives are needed and e.g. Agroscope do researches about cisgenic possibilities to bring resistance enconding genes into apple tree genomes and keep the positive phenotypic characteristics of the different apple cultivars. [6]

3. Growing this genetically modified plants have a big potential. Besides concerns about negative effects it would be possible to reduce the needed amount of pesticides and lower the impacts on the environment. [7]
The moratorium for the commercial cultivation of genetically modified plants entry into force in 2005 [8] and will last at least till 27. November 2017. [9] Till this date it is forbidden to cultivate genetically modified organisms or rear genetically modified animals, except for research purposes. [10]

I belief that if the moratorium changes and it becomes legal to cultivate genetically modified plants, there will be still mistrust against the new cisgenic plants. If the prizes for seeds and plants are on the same level some famers will jump on the bandwagon and gradually others must go along with it. I would say below average it will become even cheaper to cultivate cisgenic plants, e.g. resistant apple cultivars without the amounts of pesticides or cropper/sulphuric compunds and if the acceptance in society rises there will be more and more cisgenic apple cultivars and plants in general.

4. First, there will be a lot of people who will not buy genetically modified plants as a matter of principle or because of fear of negative health effects or negative changes in the environment. The fact that the inserted gene(s) in cisgenic plants come from organisms sexually compatible with the target crop should rise less environmental concerns and increase consumer's acceptance. [3]

I would say, that after a period of time the acceptance really rises and if there is the possibility to cultivate e.g. totally resistant apple cultivars with the same gustatory attributes and the same prizes like popular apple cultivars today the sales market will grow.

Refereces:

[1]       http://www.naturwissenschaften.ch/topics/green_genetic_engineering/agriculture/
gmo_switzerland/gmo_apples, accessed 20. May 2016

[2]       Schouten, H. J., Krens, F. A., & Jacobsen, E. (2006), Cisgenic plants are similar to traditionally bred plants, International regulations for genetically modified organisms should be altered to exempt cisgenesis. EMBO reports, pp 750-753.

[3]       Vanblaere T., Szankowsk I., Schaart J., Schouten H., Flachowsky H., Broggini G. & Gessler C. (2011), The development of a cisgenic apple plant. Journal of Biotechnology, 154, pp 304-311

[4]       http://www.pflanzen-forschung-ethik.de/konkret/aepfel.htmlv, accessed 20. May 2016

[5]       http://www.swissfruit.ch/de/apfelsorten, accessed 20. May 2016

[6]       http://www.vinquest.ch/, accessed 21. May 2016

[7]       Feldversuch mit cisgenen Apfelbäumen auf der Protected Site in Zürich-Reckenholz, (2015), Agroscope

[8]       Miklau, M., Greiter, A., Eckerstorfer, M., Heissenberger, A., & Gaugitsch, H. (Eds.). (2013). GVO-Anbau und empfindliche Gebiete in der Schweiz, Mögliche Koexistenz- und Schutzmaßnahmen. Umweltbundesamt GmbH, Wien

[9]       http://www.umweltnetz-schweiz.ch/neuigkeiten/aktuelles/1813-gentech-moratorium-wie-geht-es-weiter.html, accessed 21. May 2016, effective 27. März 2015

[10]     Bundesgesetz über die Gentechnik im Ausserhumanbereich (Gentechnikgesetz GTG), 814.91, stand 1. Juni 2014