GMO as a mean to reduce late blight Blog entry 2

GMO as a mean to reduce late blight

There are different mechanical ways of reducing phytophthora infestans, such as controlling volunteer plants and destruction of potatoes wastes in waste heaps. The destruction of infested plants is of course crucial but means generally that it is already too late. Keeping a slow cultivation shift is also a way to avoid spreading through oospores. Chemical control through spraying of fungicides is one of the main control method in conventional agriculture. However this has a heavy impact on the environment. In organic farming, biological control could be a good way to avoid fungal infections as mentionned by Pal and McSpadden [1]. Finally growing resistant varieties is of course a good way to control the disease pressure of P. infestans.  

Among the different methods for conferring fungal resistance, or any kind of genes, in GM plants, one happens by the mean of soil bacterias, namely the Agrobacterium tumefaciens. A lot of different studies, such as the one by Fillatti et al. shows that A. tumefaciens is a good vector for gene transmission [2]. The fungal resistance is first inserted into the DNA of this bacteria. The DNA of the bacteria is then naturally transmitted to the plant DNA during plant infection, leading to the integration of the fungal resistance gene in plant tissue. Since not all the cells are infected by the bacteria, different selections are possible to isolate resistant cells. Another method is the high speed bombardment method where the specific gene is directly “bombarded” into the plant cells. This method was used for the papaya gene mutation.

One of the advantage of using the gene of the close relative Solanum bulbocastanum is that those are cisgenes, which mean that they come from a relative with which the potato can naturally crossbreed. Also you don’t have to tamper them, the gene can come along with its native promoter and terminator [3]. Fortuna was genetically modified because with classical breeding it would have taken much more longer to develop the resistance and it would have come with other undesirable characteristics, such as poor agronomical properties (coming from the wild potato species). Bridge cross would also have benn needed, making crossbreeding challenging [3].

Apparently, BASF encountered a wide public opposition to their project of growing Fortuna in Europe. They had asked cultivation and marketing approval from the EFSA in Europe in October 2011 but they stopped GMO development in Europe in 2012 and moved to US, due to the tougher opposition and regulation in the EU. The fields were destroyed by activists and public opinion feared that it would harm health and biodiversity.

The swiss moratorium forbids to cultivate GMO in Switzerland until 2021 [4]. However if it was possible I’m still not sure I would cultivate Fortuna. Basically I find it good to avoid having to spray fungicides over potato cultivations and I’m aware that Fortuna is not a threat for the environment since potato plants don’t grow naturally here. However for ethical reasons and my unwillingness to share the patenting of life allong with the binding costs that I would have to pay to the agricultural industry I would refuse to build such potato.

References

[1]	K. K. Pal et B. McSpadden, «Biological Control of Plant Pathogens,» The plant health instructor, Ohio State University, 2006.
[2]	J. J. Fillatti, J. Kiser, R. Rose et L. Comai, «Efficient Transfer of a Glyphosate Tolerance Gene into Tomato Using a Binary Agrobacterium Tumefaciens Vector,» Nature Biotechnology, n° 15, pp. 726-730, 1987.
[3]	T. STORCK, T. BÖHME et H. SCHULTHEISS, «Fortuna et al. Status and perspectives of GM approaches to fight late blight,» Editor H.T.A.M Schepers, St. Petersburg, 2011.
[4]	O. f. d. l. OFAG, «Rapport sur les résultats de la procédure de consultation relative à la modification de la loi fédérale sur le génie génétique (Intégration des résultats du PNR 59 et des régions sans OGM) et à l’ordonnance sur la coexistence.,» Confédération suisse, Berne, 2015.