(10g) Genetically-modified plants - pros and contras

Recently, I saw an interesting short video (although, what can you discuss in 5 minutes?) in which a scientist discussed genetically-modified (GM) crops (and food) with someone from UK's Green party. She said she wasn't completely against GM crops but thought it is not good that only a few companies rule the planet concerning GM crops and that larger numbers of crops should be grown. Indeed, she is right that it can't be that a few companies are becoming so powerful they silent everyone who criticises them, not only politicians but even others working in this field of sciences. On the other hand, the professor was very right to say that many scientists not even had a chance to test the safety of GM plants because they are not even allowed to grow and test them, except on a small scale in their own labs (or in some developing countries).

Over the past few months there were a number of occasions when people protested against GM crops from Monsanto and others but I am sure many protested against GM crops in general. Here I will explain why I think these protesters were right and wrong at the same time.

Monsanto claims they developed GM seeds to help farmers getting larger yield of crops in developing countries. It seems they have two main developments: one type of GM seeds are good as they contain a gene from Bacillus thuringiensis (Bt) (a bacterium that produces its own insecticide) and thus these plants become toxic to insects , resulting in the use of fewer insecticides while yields increase. The website even explains how to prevent that too many resistant insects arise (but do farmers follow these guidelines?).

However, they also have plants that are genetically-modified to withstand powerful herbicides. I think this path should change because Monsanto becomes a chemical company that wants to sell pesticides (= substances meant for preventing, destroying or mitigating any pest) and herbicides (commonly known as weedkillers, are pesticides used to kill unwanted plants). I believe them when they say they developed GM plants that can withstand (their) pesticides and resulted in increased yields in countries where crops are often destroyed by insects and diseases and overgrown by weeds.

But the information we receive today shows they now want a return for the money they invested in developing GM seeds by trying to sell their GM seeds to everyone, even when yields are already large and there are hardly any pests. They developed strong pesticides and herbicide that are able to destroy everything except the GM plants Monsanto developed. As a result only edible plants grow while everything else is destroyed, and this should be positive.

However, it seems farmers are not allowed to take seeds from their plants but have to buy them (companies even want to sell 'suicide' seeds which are sterile so farmers have to buy each year new seeds). Thus it seems that for Monsanto it is not enough to sell poisons but they also want that farmers buy their (expensive) patented seeds, even when farmers are poor and have to get loans to be able to buy both seeds and poisons. As a result, according to newspapers (some spreading these stories because they are opposed to GM plants but too many are reporting similar stories), thousands of Indian farmers committed suicide as they were no longer able to pay their debts, although Monsanto claims these suicides started before GM crops were developed. One can indeed imagine farmers who lost whole fields to pests may commit suicide as their livelihood is destroyed and thus Monsanto's and others seeds and pesticides can help (although they may be more useful for big farmers). Still, these poisons are solved in water and thus may increase pressure on water supply where there is a water shortage while as they are water-soluble they can enter ground water.

In addition to the suicides, some weeds and maybe also insects already start to show resistance to the poisons and thus stronger poisons are developed and used to kill the resistant organisms while this may also require the development of new GM plants so they can survive these new poisons. Thus, plants and insects adjust to new challenges and develop resistance (toxins may cause more mutations in the genome and thus the likelihood new species arise becomes more likely), most likely first with the weeds and insects one wants to destroy while farmers are only able to use products from Monsanto because the stronger the poisons and the more these poisons are used, the more toxins in the ground and thus nothing but Monsanto's GM plants will grow until harmful plants and insects will again develop resistance or maybe poisons become so strong nothing except GM plants can survive (and that is called a desert). Recently, even the US government decided an extra year is needed to study the possible harmful effects of the stronger poisons and GM crops before granting a license (but I can't find the link).

Further, I agree with the argument of the Green party against the use of mono-culture because we know that growing each year one type of plant in the same field will exhaust the soil and thus probably after a few years yields may decline. Even growing different GM crops to prevent depleting the soil but using the same poisons will result in the development of resistance by weeds and insects, as discussed above. In addition, the ground may contain so much toxins that, after soils are depleted for the GM crop, it may be impossible to grow other crops for a number of years until the poisons are washed away, resulting in less yield. People also need a varied diet and this can only be when many different plant species are grown in a certain area. This will also slowdown the occurrence of pests as mostly diseases and insects prefer a few specific plant species and not others. Insects even developed resistance against plants containing the Bt gene in one area of the world (as a consequence a stronger seed was introduced worldwide so that in future if resistance arises there is no stronger seed available, or they may become poisonous). When only a few crops are cultured, all insects are forced to eat the ones that grow or die while if also weeds grow (= many plant species), insects may prefer the weeds instead of the crops. The Amazonian forest is an example where many insects live together without pests destroying the forest, although that too becomes a mono-culture as we replace the forest with certain plants that are more profitable and thus pests will emerge. Even drinking water may become dangerous if the poisons are washed away into rivers and groundwater that people use for drinking. We know from the past that the use of strong poisons to control pest (such as DDT) is bad for the environment as well as for us. Progress in science is good but this should not ignore the lessons we learnt from the past.

Thus, as we know from the past, the use of poisons such as pesticides and herbicides should be limited to the strictest minimum (and the most dangerous one only used when absolutely necessary) and this for the shortest possible time. To prevent that an insect has each year its preferred food so their numbers can increase until they become a pest, different crops should be grown each year so insects need to invest energy in adjusting to changes in their environment and remain small in numbers. When poisons are used, different poisons (not at ones) should be used to prevent that resistance to one poison can develop over time. Thus, change each year the crops that are grown and use poisons only when necessary.

Thus, although Monsanto's intentions may be good and sometimes poisons are necessary when there is a major pest, I think its technique is not the preferred one because poisons are dangerous and can kill while people become dependent on their products as nothing else can grow, not even (GM) seeds sold by other companies because those plants will die too. And as patents protect Monsanto's invention, other companies may not be allowed to develop GM plants that survive Monsanto's toxins (the same is true for other companies that follow the same path) and thus competition between companies is further reduced and seed, pesticide and herbicide prices can go up. However, I am not against GM plants perse because indeed it can result in increased yields or have other benefits (see below).

GM crops should result in the use of less pesticides. That is one of the reasons why I am sceptical about the seeds produced by Monsanto that withstand strong poisons to kill everything except Monsanto's GM plants. Even when Monsanto's products allow the use of fewer chemicals, are farmers sufficiently educated to use less (even none when not necessary) or are they using as much as in the past to be sure weeds and pests are killed as they don't trust small amounts? Still, Monsanto (and others) may use their knowledge to develop other GM plants that may be much more acceptable.

GM crops that I think may be very useful - while others may be less

The above shows that I am not in favour of the development of GM crops that survive chemicals as this will probably result in overuse of pesticides and herbicides that are dangerous for the environment and kill non-discriminatory (sometimes even humans) while resistance can occur so that even stronger poisons need to be used. These toxins also destroy beneficial insects that are needed. Nevertheless, they may be useful when there is a pest so growing food can continue while the pest gets destroyed. But I think these seeds should not be used to prevent possible pests that may not arise.


In addition, GM plants that produce molecules against pests should be very well checked before allowing them to be eaten by humans so we can be sure they will not kill us although they may be good use in for instance cotton plants. There are indeed molecules that are harmful for insects and diseases while not for humans, at least when present in small quantities but this needs thorough investigation. Even the molecules produced by GM plants that protect them against insects need very well investigation to be sure they are not dangerous for humans, and if they are not, this should be clearly communicated with documents proving it. Therefore, as the professor mentioned in the video, it is very important scientists are able to test the plants they developed to be sure they are save and thus people should allow that scientists test GM crops while scientists should be as open as possible about the results they get, good or bad.

Three varieties of geraniums. After I found holes in the leaves of the two plants on the right, I discovered two caterpillars. The plant on the left was much less eaten by these caterpillars. I let the caterpillars survive in the hope they would butterflies (the two animals didn't kill the plants). I'm not sure whether the plant on the left is genetically modified, but the diversity made sure not all were eaten.

However, I can imagine other uses of GM plants that may probably much easier be accepted (although some people will always resist) such as GM plants designed to survive difficult environments (e.g. drought or heat or great heights). E.g. some GM plants may be easier to grow in dry environments with higher yields as a result than the original plants and thus more people can be fed. But then I think one should not only study the safety but maybe also whether there may not be negative effects in the longer term such as a faster depletion of the soil (and if so, how to prevent that).

Another positive development can be when GM plants produce more nutritious food although here I think we should also be careful because too much of something can be harmful. Still, when original plants are very nutrient-poor because they grow in a certain environment, then one can imaging that modified plants that can grow in these regions but produce more nutrients will be beneficial (although again we should be careful these modified plants will not result in further depletion of the soil). But greed may also be a problem when one wants to sell these products over the whole planet, even at places where they may not be needed. For instance, Golden Rice has been developed, a rice variety that originally produced three times more beta-carotene (important for the formation of vitamin A) than the original rice and this is important in areas where people suffer from vitamin A shortages. But it seems that the second generation produces up to 23 times more beta-carotene than the original rice and then I wonder whether one day we may see people with illnesses as a result of an overdose of vitamin A. And thus this needs to be investigated. Further, I also wonder why people suffer from vitamin A shortage: look at the map and you notice it is a problem of poor countries, probably because people have a poor diet because they can't buy food and thus Golden Rice may not be a solution if people can't afford the rice, certainly not when it can be sold one day in developed countries where it probably will be advertised as good against vitamin A shortages (that hardly occur here). Thus, I don't suggest Golden Rice should not be used but it should be very well investigated to be sure doses are not too high while people should be able to afford it ones it becomes available. Maybe a vitamin tablet may be better suited to reverse vitamin shortages than eating on a daily basis plants that produce larger amounts of vitamin A that can damage the liver. Plants may also produce variable amounts and thus one can never be sure about the dosage that people receive while tablets can be carefully given according to the individual person and for as long as necessary. The plant producing the lower amount of vitamin A may be used to prevent a shortage of vitamin A. This leads us to the next use.

GM plants that produce medicines will be great but maybe they should be grown under controlled conditions and not freely distributed unless their safety is well established. These may include plants producing large amounts of (pro-)vitamins that can be isolated so their amount can be determined correctly and people can receive a well-known doses in the form of a tablet (unless it is well established the plants are save for which research is needed). Today already molecules are isolated from plants to cure illnesses but the quantities are very small; therefore genetically modifying these plants that have already the mechanisms to produce the molecules may result in larger yields and thus cheaper drugs or drugs available for more people.

GM plants may also be used to increase biodiversity (indeed, the opposite of mono-culture). While the destruction of nature leads more and more towards fewer and fewer plants and animals, genetically-modified plants and even animals can result in an increased number of species. We can end up with flowers that are larger, more colourful and/or smell stronger (and the opposite for other people). During the past centuries people tried to achieve this by fertilising plants (and animals) so we got a larger variety of plants. These new plants can then multiply and be used to replace the large numbers of plants (and animals) we destroy today and thus genetic engineering may one day be used to increase biodiversity, even maybe bringing back from the past some species that are now extinct (although I would not include T. rex because too dangerous). An increase in biodiversity also includes an increase in different food products, although I think we should not design food that taste too differently from its original (e.g. when a tomato tastes like cucumbers, people who don't like cucumbers may also stop eating tomatoes). Therefore, people should know what they buy so if they prefer the plants that originated from nature they can distinguish them from GM crops. This will also prevent that people are angry because they have no choice.

By the way, I think a more elegant method to reduce numbers of pests is to release infertile male and female insects that will mate with the one living in nature. As a result there will be less off-spring of a specific species while species that cause no harm do not suffer (although maybe one day insects may recognise fertile from infertile insects?). Of course, this method should in general not exterminate all insects except the worst ones because we don't want a planet without for instance butterflies, even when many farmers consider their larvae to be a pest. Therefore, there also needs to be some space for nature.

Independent assessment

Probably people will only accept that GM food is save when it has been assessed and considered safe by independent scientists from institutions such as universities or government agencies that receive little if any funding from industry. And as universities today are forced to work together with industry (if not scientists are labelled out-of-touch and living in an ivory tower and receive less funding while people are less likely to believe scientists who work close with industry; indeed scientists often can't win), people will remain sceptical.

Therefore, probably the best solution is that government agencies set criteria that need to be fulfilled before GM products can be considered safe, as is already in place for medicines. Government agencies then approve products based on the data provided by the universities and industries. If this is already done then it should be communicated much better so people understand better what is being done to protect their health (although there will always be those who only trust themselves).

In addition, universities should be able to investigate GM crops developed by the industry and other universities and thus not only during collaborations. This means: companies and universities can't claim a patent prevents universities from investigating the safety of their GM plants. As long as people can't be sure that research is done on GM plants and GM food to determine their safety by independent institutions, we will have a continuous fight against this kind of products. If developers want to sell their products, they will need safety approval by independent institutions or sell nothing because resisting this means they do not thrust their product will be declared save. Of course, this also means that scientists can test the products and thus people shouldn't destroy the experiments. Even then, products should be labelled as organic or normal or GM. This way, people will be able to see that people who eat GM food are as healthy as those eating organic, and fear will disappear. But as long as companies are afraid that their products are labelled as GM food, people will continue to question their honesty. Indeed, first sales may be low but in the longer run they may go up.

Another possibility is that all none-GM food are removed from supermarkets so people have no choice. Although then I fear resistance will continue to grow for some time and if one accident may happen, there will be a major setback for this kind of products.

No sterile seeds

Today, often people argue that GM plants should be sterile because many people believe we should prevent that a GM plant can produce seeds and spread them in nature as this will prevent them from mixing with or even replacing the original plants. Many companies agree with this because then they can sell sterile seeds that people will need to buy.

However, as we prefer fewer (no) insects on our plants, we may prefer GM flowering plants that are avoided by pests such as plant lice or caterpillars (there are roses where plant lice die after a few days) and thus GM plants will replace the original plants if only for the convenience. But, when these GM plants don't produce many if any seeds while we may prefer them instead of the original plants (of which the few remaining original seed-producing plants may be eaten by insects if we don't use insecticides), we may end with plants that can't reproduce as they don't produce seeds while those that can reproduce disappear because they are eaten or no longer wanted in our gardens. Then we only need a disaster such as a resistant pest and we may have few plants left.

Therefore, I think we need to produce GM plants that are able to reproduce while, as often in nature, they may probably not really mix because each strain has a (slightly) different genome that doesn't mix well with genomes from other strains (e.g. many GM plants have extra genes and thus their DNA is larger than the original (although only a little)). Certainly when the flowers differ (e.g. they are larger) it is less likely DNA gets mixed as this may attract different kind of insects. But when these GM plants are allowed to reproduce, if the original species disappears, the other can still spread their seeds.

In addition, by growing different varieties together, insects are able to eat the plants they prefer most while it is less likely they spread to other surrounding plants if there are a few in between they don't like (e.g. the smell keeps them away).

Finally, it will also allow farmers to harvest their own seeds, resulting in lower seed prices in shops so that farmers continue buying the seeds while if seed prices are too high, farmers will take their own seeds even when that means not all crop can be used to sell and even when it takes more time.

... But of course, nothing in life is straight-forward, thus science isn't either. Indeed, if a plant is used to produce a very poisonous molecule that can be used in the treatment of for instance cancer, or a plant is very beneficial but will overgrow all other plants, then it may be better to have a plant that can't reproduce and thus not spread in nature. Therefore, scientists have to establish the safety profile so it can be determined what can be grown safely and what is best grown in a lab or sterile, if necessary, sterile in nature.

In conclusion, it is good scientists start to develop new plants (even animals) but the safety profile should be well checked and products should be approved before being allowed on the markets. Mainly products that can result in fewer pesticides should be used and those that are to the advantage of all farmers, not only the big ones. Also customers can benefit from these products in the garden but also on their plate when diversity increases, unless some major players want to protect their own markets by blocking others. And in contrast to the past, the newly developed products will be thoroughly checked before they are released on the markets so we may have the safest food ever available. Even people with allergies for some food may benefit if some companies focus attention to developing crops without the allergens.

Those who really believe in GM crops, try to convince the people by talking to them but also by listening because some of their worries may be real and thus should be solved. In doing so, the best and safest products can be produced. But when something is done in a hurry or little is explained, one can be certain that protests will continue to increase, certainly when things go wrong, causing a setback for many years. Even imported natural occurring plants can cause harm, still we continue importing plants because most are harmless; similarly, we will continue making GM plants and this under much stricter safety checks than the import of foreign plants. Therefore in future, safe and beneficial GM plants and food will become available.

I think this article is a good summary.



Please, when you think I made some mistake, let me know so I can decide to correct it as science is about discussions to make corrections or argue against them. In addition, if you know other uses of GM plants and insects let the world know, but question first why you think it has more benefits than negatives (and don't come with the argument it has only positives because each positive will probably has a negative until only benefits are proven). Intelligence wonders about the advantages and disadvantages, then reaches a conclusion and may even change its own conclusion if arguments are strong enough against it so strategies can change to bring something better that is more likely to survive in the future.