Tuesday, May 7, 2013

A transgenic plant for the Swiss agriculture


1.       Define which problem – in your opinion - will be the greatest challenge for Swiss agriculture in the future.

In Switzerland we have the privilege to have very fertile soil at our disposal and it will probably still take a very long time until a shortage of water will limit our agricultural production. Even though extreme climate events are becoming more frequent and the weather more unpredictable, I think climate change is currently not the main problem for the Swiss agriculture. The bigger concerns nowadays are about pests, about suitable pest management/control and pest monitoring. Not only newly introduced pests are causing huge problems but also the pests we’ve had in Switzerland for a long time are still threatening crop yields today and the application of many pesticides is often necessary.

2.       What kind of plants would be needed to address this problem?

The best way to combat pests is to achieve resistances in crops against the pests which threaten them. Many resistance genes can still be found in old wild types of the cultured plants and with conventional breeding methods these resistance genes can often be successfully reintroduced into the culture by crossbreeding. But these techniques are very complicated, uncertain and take a lot of time. Therefore there are many attempts to achieve such resistances by genetic engineering. In doing so, it is best if the resistance to the pest organism  is generated by several genes, so that the pest organism will not adapt and become resistant to the transgenic plant. Thus, the GM plant might not be fully, but permanently protected.

Since I focussed on viruses in my last blog entry, I first thought of addressing this problem again. Virus resistances have already been achieved in various plants, also in potatoes. Potatoes are a very important crop in Switzerland but are affected by a lot of pests, not only by viruses. A much more problematic, epidemically spreading pest in the cultivation of potatoes is Phytophthora infestans, the fungus which causes the disease called potato blight.  This pest is so very versatile so that the pest control methods always start to become ineffective again. This is why, in the end, I chose this topic.

3.       What gene would you need in your plant? Can this gene be found in the gene bank (maybe from a different species)? Please provide some details.

In order to attain Phytophthora resistant potatoes, not only one single gene is needed, but the resistance is sought to be constituted by several genes since Phytophthora is such a versatile pest. There are wild type potatoes which show resistance characteristics, but by crossing there are also the bad traits of the wild potato which come along. One has to get rid of these unwanted traits afterwards by a long backcrossing procedure with the cultured potato. With genetic engineering it is much easier and the first resistant variety Fortuna had been achieved in 2006 by BASF Plant Science, introducing two resistance genes from the wild type Solanum bulbocastanum. (Early in 2013 the company stopped the admission procedure in Europe due to the strong refusal of the population).
The University of Wageningen is still working on a research project (DuRPh) aiming to develop potato cultivars with a durable and a high level resistance against late blight (Phytophthora). They found that also other wild types can serve as resistance source, such as Solanum demissum. Among the 11 R gene differentials, which were introduced from S. demissum, especially R8 and R9 differentials showed broad spectrum resistance both under laboratory and under field conditions.
Since these resistances come from related species, the “modified” plants are called cisgenic instead of transgenic.

4.       The Swiss National Foundation finances scientific projects developing genetically modified plants for the Swiss agriculture.  State two main arguments, why your project should be financed too.

-          The conventional pest control agents to combat Phytophthora are very expensive. The potato production costs could be decreased.
-          A conventional field with potatoes is treated with fungicides around 10 times a season. These pesticides are very harmful for the environment and the numerous applications are not climate friendly at all.

5.       If you would be the person responsible for grants at the Swiss National Foundation – would you finance your project? Explain in two sentences.

I still stick to my denial of transgenic crops and would therefore not finance the project. I do not believe that genetic engineering will ever come up with ultimate solutions, but would only temporarily facilitate the work of farmers. In the long run, it is not the right approach.  

References:

www.wageningenur.nl. (2012). Von http://www.wageningenur.nl/en/Expertise-Services/Research-Institutes/plant-research-international/DuRPh.htm abgerufen
www.transgen.de. (30. Januar 2013). Abgerufen am 7. Mai 2013 von http://www.transgen.de/pflanzenforschung/anbaueigenschaften/845.doku.html
ETH Zürich. (19. April 2011). www.path.ethz.ch. Abgerufen am 7. Mai 2013 von http://www.path.ethz.ch/education/courses/online_skripte/diagnostik/kartoffel/index
Kim HJ, L. H. (23. November 2011). Broad spectrum late blight resistance in potato differential set plants MaR8 and MaR9 is conferred by multiple stacked R genes. Wageningen.
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Friday, April 12, 2013

GM plants in the pipeline – what has already been tried


1.       Which paper did you choose as your first step? Why did you choose this paper? Please give a short summary (2-3 sentences) of this paper.

I first thought about subjects other than drought which we defined as the major challenges for the Swiss agriculture. I decided that I wanted to know more about resistances which scientists had already tried to achieve in plants. I therefore thought to address the challenge of new pests arriving in Switzerland.

I found the very general and long article “Engineering Pathogen Resistance in Crop Plants: Current Trends and Future Prospects” (accessible when connected to the ZHAW) http://www.annualreviews.org/doi/pdf/10.1146/annurev-phyto-073009-114430

The article explains the huge potential of different genetically modified plants with new resistances against fungal diseases, bacteria and viruses. It also explores the reasons, why so few new crops have been introduced to the global market. It gives an overview (the charts) of the plants that have been produced with resistances so far and then highlights some of the more recent promising strategies.

I limited myself to the introduction and summary points and decided to mainly focus on virus resistances. There are several viruses also causing damage in Switzerland. What is more, biocontrol is not possible with viruses and in contrast to bacterial of fungal diseases there are also no other possibilities to free the crops from them. This is why I found it particularly interesting to focus on virus resistant GM plants.

2.       What kinds of plants have been genetically modified addressing your chosen future challenge in Swiss agriculture?

Many plants have already been genetically modified in order to be resistant to viruses. Here a few examples:

-          Squash: resistant to the Cucumber mosaic virus, Watermelon mosaic virus 2 and Zucchini Yellow mosaic virus
-          Papaya: resistant to Papaya Ringspot-Virus
-          Melon: resistant to Papaya Ringspot-Virus and Zucchini Yellow mosaic virus
-          Wheat and other cereals: resistant to e.g. Barley Yellow dwarf virus
-          Tomato: resistant to the Tomato yellow leaf curl virus
-          Tobacco: resistant to the Tobacco mosaic virus
-          Potato: resistant to the Potato leaf roll virus or Potato spindle tuber viroid and many more
-          Chrysanthemum: resistant to the Chrysanthemum stunt viroid
-          Plum: resistant to the Plum pox potyvirus (PPV)

Most of those plants, except for tobacco, melon and papaya, are grown in Switzerland and therefore the efforts of genetic engineering to make these plants resistant to detrimental viruses could be relevant for us, too. I will focus on the Plum pox potyvirus later.

3.       Which genes were used?

All viral molecules, including genomes, represent potential targets for a genetically modified resistance strategy, since these molecules are not separated from the plant cell by any physical barrier. Viral coat protein (CP) genes and viral non-structural protein genes, as well as antisense DNA and DNA for viral satellite RNA, have all been used to produce virus-resistant plants, but CP’s are most commonly used.

Almost all viruses express proteins of the following three types: coat proteins (CPs), movement proteins, and proteins involved in genome replication. Natural defence mechanisms in plants are known to target these proteins as well as the viral genomes.

The strategy is the pathogen mimicry or pathogen-derived resistance (PDR), where the plant is designed to express important, recognizable features of the pathogen.  

4.       Which of the transgenic plants you studied do you find most useful? What other solutions could you think of to achieve the same effect?

I especially studied the paper “Genetically engineered resistance to Plum pox virus infection in herbaceous and stone fruit hosts”. 

http://www.landesbioscience.com/journals/gmcrops/IlardiGMC2-1.pdf

The Plum pox virus infects plum, apricot, peach and also wild Prunus species and is the causal agent of Sharka, the most detrimental viral disease affecting stone fruit trees.

I know that the Plum pox virus is again a problem in Switzerland at the moment and that all the measures are taken in order to eradicate this virus. It is a quarantine organism which means that strict controlling is compulsory and the contaminated trees have to be reported and destroyed. These measures are the present solution to the problem. GM trees would offer an alternative in the future.

http://www.agroscope.admin.ch/index_phytosanitaire/02224/02239/02241/index.html?lang=de

But there are also naturally tolerant species and it might also be an option to try and make trees Sharka tolerant with conventional breeding methods, though this is often difficult for trees and takes longer.


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Thursday, March 21, 2013

GM plants in Switzerland - pros and cons


The transgenic plants grown today are cotton, soybean, corn, canola, alfalfa, sugar beets and some squash and papaya. They contain mostly genes that confer resistance against an herbicide, against insects or viruses. Newer plants contain more than one additional gene, leading to a plant with more than one resistance (‘stacked-traits’).

1. Could one of these plants be useful in Swiss agriculture?

Corn, canola, alfalfa, sugar beets and squash are plants, which are commonly grown on Swiss farming fields. All these plants would in transgenic form offer new possibilities and promise higher crop yields.  

Corn: Especially now that the western corn rootworm (Diabrotica virgifera virgifera) reached Swiss ground and occurs occasionally, it might seem tempting to cultivate BT-corn. This transgenic corn is (supposed to be) vermin- resistant and would therefore prevent the spread of the corn rootworm. But up to now, the corn rootworm has caused no damage in Switzerland, thanks to a well-managed crop rotation. This technique will not lose its effectiveness in the future, considering a wide spectrum of animal pests, and it is the best thing to do for soil fertility and structure anyway (managing the nutrients in the soil instead of using mineral fertilizers is also sustainable and climate friendly). Thus, there isn’t any necessity for Swiss BT- corn at present. What is more, in the USA the corn rootworm already starts to develop a BT- resistance so that even supporters of genetic engineering are now saying, that one should not only plant BT crops (listen broadcast).
Canola: Transgenic canola is usually herbicide resistant (“roundup-ready”, meaning resistant to Roundup, which is glyphosate, a broad-spectrum systemic herbicide) and often also modified in other traits, namely in its components, for instance containing less trans-fats and more omega-3 fatty acids. A lot of these qualities were also successfully achieved by conventional breeding methods. Nevertheless, canola is still highly susceptible to animal pests and diseases and a really strict crop rotation is essential. In conventional farming herbicides, insecticides, fungicides etc. are applied. In organic farming there is almost nothing that can be done to protect canola crops apart from crop rotation. But also transgenic canola does not solve this problem. There’s only the advantage that the applications of herbicides can be reduced by using the broad-spectrum herbicide glyphosate instead of specific herbicides, which ideally also reduces some of the costs.
Alfalfa: Roundup-ready alfalfa is also resistant to the broad-spectrum herbicide Roundup which therefore also simplifies weed control in cultivations and may reduce herbicide applications and costs. However, I do not see why a strict weed control is necessary for this plant. Alfalfa is primarily grown in big fields as forage plant. Cattle or other animals do not care if they feed on some other plants along with it. (The inappropriate forage of cattle is another huge problem itself)
Sugar beet: Sugar beet is a root crop which demands a good preparation of the soil. Deep ploughing and a mechanical (and chemical) weed control are necessary procedures. Here, cultivating glyphosate-resistant transgenic sugar beets would be more convenient, too. Weed control could be easily done with the application of glyphosate. But growing sugar beets has a long tradition in Switzerland and I believe that the methods and equipment for weed control have been optimised and crop yields cannot be increased significantly growing transgenic sugar beet.
Squash: Transgenic squash is resistant to infections of two specific viruses. Since there is not much information available on this subject, I am not sure, if the cultivation of transgenic squash had really proved successful and if those viruses have actually caused problems in Switzerland.

Considering all species, I disagree with the introduction of transgenic plants. Genetic engineering does not offer the right approach to solving the problems which, from my point of view, arose from industrial monocultures and intensive agriculture. In my opinion genetic engineering tries to combat the symptoms but does not solve the real causes!
Furthermore, with the widespread cultivation of Roundup- resistant Monsanto products the development of similar resistances in some weed species is emerging as a (costly) problem. The same is the case for BT crops as we hear in the broadcast.
And if we eliminate one pest animal, the next one already starts to invade.
I also do not believe that genetic engineering can solve the problem of hunger and the global food crisis.

Transgenic canola:

Organic canola cultivation:

Transgenic alfalfa:

Broadcast on BT- resistant Corn Rootworm (Diabrotica virgifera virgifera):

Articles on transgenic food and hunger: 

2. Today, the safety of GM plants in not an issue in the public discussion anymore. Social, economic and ethical arguments are more important. 

A lot of the following arguments are also valid arguments against conventional monoculture systems!

Social:

Cons:
-        Dependency on multinational companies such as Monsanto
-        Dependency on world market
-        Farmers have little to no relation to the plants they grow and loose the knowledge about natural interactions etc.
-        Do farmers in third world countries have a real option or choice?
-        Higher production rates rarely empower farmers of third world countries and do not guarantee a better life for them (-> dependency). The distribution of food is the problem, not the quantities that are produced worldwide. (Or as some see it, there are too many people on this planet)
Pros:
-        Higher production rates augment food security (?)
-        Higher salary for farmers (?)
-        Side-effect: According to the NFP results BT-corn is healthier because it contains less mycotoxins.

Ethical:

Cons:
-        Modifying the gene of any living organism is an interference that goes further than any breeding method or selection that has been done so far. Genes of different organisms are mixed up. The gene-cocktails we produce show how little respect we have towards life.
-        Are patents on plants (and animals) or on DNA-sequences ethical?
-        The latest research showed that plants are able to communicate and even to remember. Therefore we should treat plants accordingly and even speak about and respect the dignity of plants.
-        Is the way pesticides function and attack the metabolism of plants and animals and eradicate them at once ethically correct? It is a tightrope walk how much influence humans should exert. Alternative methods are crop rotation and biocontrol.
-        Weeds are living beings! Pest animals are living beings! The web of life is very complex and we cannot compensate the loss of species. Humans rely on the diversity of life!
Pros:
-        We bear responsibility for the wellbeing of human beings we rely on. So food security in third world countries should be increased or rather guaranteed (though really with GMO’s?)
-        Plants can be modified to cover the needs of humans, e.g. golden rice. (-> Attempt to combat symptoms? Will this ensure a balanced nutrition? Farmers should not only be producing for the world market, but for a diverse self-supply)

Economic:

Cons:
-        According to the results of the NFP 59 the acceptance of GMO’s is not given among the Swiss people. The attitude is rather sceptical and seems to be durable. Therefore the farmers’ Union doesn’t see much potential for products from GMO’s at present.
-         The results of the NFP also show, that a lot of costs would arise, if GMO’s were to be cultivated in Switzerland next to conventional and organic crops. Profitability is not given.
-        On an international basis:  Will the costs really drop? Will third world countries really be on the winning side? (I assume multinational companies will make sure to increase profits…)
Pros:
-        Lower costs due to fewer applications of pesticides (but won’t the expenses stay high through the dependency on products from those huge companies?)
-        Higher salary for farmers thanks to higher crop yields (will farmers really be the ones that profit?)


Results from the national research program NFP 59:

Opinion of the farmer’s union:


The rights of plants:

Ethics and plants:

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Friday, February 22, 2013

What are the most demanding current issues and future challenges in Swiss agriculture?

The Swiss population calls for an agricultural sector which meets market demands and operates in an environmentally friendly way. Meadows and pasture make up a full three quarters of Swiss farmland, with cereals and vegetables being confined to the lowlands. About one third of farms are involved in crop production. While many Swiss people still have a romantic image of what agriculture in Switzerland should look like, changes that have occurred within and outside the country have had a great impact on Swiss agricultural. Today famers have to compete on the market and protection against international competition has been reduced. Small fields – high cost, what other challenges is Swiss Agriculture facing? 


One of the biggest issues in Swiss agriculture will be to face and to deal with the consequences of climate change. Even though the scenarios vary according to the different climate models, climate change is now accepted as a fact and the discussion is now centred on strategies and solutions to adapt.
Until 2030 an average increase of +2°C in temperature is expected. This would not yet cause big problems for the Swiss agriculture, since we’re in a rather cold climate zone. The growing season would even be prolonged by a couple of days and cultures with a greater potential yield could be grown. But there are other expected changes, too. There will be less precipitation in summer, which would mostly affect the areas that are already very dry, such as the Wallis. What could make it problematic for the whole of Switzerland is, if there will be high fluctuations. And this is what we have witnessed over the last few years.

The probability of extremely high temperatures and drought in summer is rising. By differing the date of sowing and choosing other species/breeds for cultivation, some adjustment can be done. But the risk of crop losses due to heat damage is increasing. Also other extreme climate events became more frequent. Increased erosion, the loss of fertile soil and storms are other demanding issues.

Furthermore the production costs will increase through augmented irrigation, pest and weed control. And this is another great challenge for Swiss agriculture:
In Switzerland, insects (pests) and weeds (pest plants) are profiting from the climate change, mainly when winters become milder. In addition to that, globalisation entailed the exchange and introduction of organisms. As a consequence, a growing number of newly introduced pests and diseases are now also threatening the crop yields in Swiss agriculture.
New solutions have to be found to combat these pests and diseases, and an even greater challenge arises, when these organisms develop resistances to the applied pesticides.

At the same time, as was mentioned in the introduction, Swiss farmers, as well as all the farmers of industrial countries, are under the pressure to reduce CO2  emissions caused by the modern production methods and to help preserve biodiversity.

Swiss agriculture and climate change:

Swiss agriculture and ecology:



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