Non-GMO labels are frequently found on processed foods as well as fruits and vegetables in the grocery store. However, these labels are fairly arbitrary because they single out specific crop modification techniques with no good reason. In this article, I aim to explore why crops are modified, to provide an overview of crop modification techniques, and to address some common concerns about the modification of crops.
Why do we need modified crops?
Crops are modified so that they have new features, known as traits. These include:
- New tastes and flavor: of course we want more flavorful tomatoes, but also sweeter strawberries, pineapples that have less acidity, etc.
- Modifications for environmental reasons: farmers may want crops that are more tolerant of environmental stresses such as extreme weather or drought
- Pest resistance: whether the pest is an insect, a virus, or a fungus, farmers need crops that can resist these so that they can have higher yields and use fewer resources.
- Modifications for large scale production: for example, fruit that are more resistant to bruising or have improved shape to deal with the challenges of transportation may be desired by producers so that there’s less damage in transit.
- Cosmetic reasons: imagine an avocado that browns more slowly when cut or pineapples that are easier to peel. The development of a crop for such purposes should not be considered frivolous: think of all the guacamole that we waste because it no longer seems appealing.
How are crops modified?
There are many different ways that crops are modified. Some of these methods have been used for centuries, others are more recent. The graphic below, which was coauthored together with Karl Haro von Mogel at Biology Fortified, highlights several of these methods. Each technique is further explained here.
The focus of the “GMO debate” has been largely centered on crops developed by transgenesis.
Different crop modification techniques can have the same end result. For example, the Opal Apple is non-browning and the enzyme which causes browning was decreased using traditional cross-breeding. The Arctic Apple is also non-browning and the browning enzyme was silenced using transgenesis. Recently, a non-browning mushroom was developed where the same browning enzyme was silenced by editing the gene using CRISPR-Cas9. Yet each of these is regulated and labeled differently.
Transgenesis has generated safe products for decades. Yet groups such as GMO Free USA and Moms Across America single out the method and consider it to be harmful despite the absence of evidence to support their claims.
Can there be unforeseen consequences?
It is often claimed that the method of transgenesis can have unforeseen consequences. However, studies that have examined and compared crops developed by transgenesis to crops developed by other methods have consistently found fewer undesired changes in transgenic crops. Examples of such studies can be found in this blog post.
All crop modification techniques have risk, including crops developed by traditional breeding. Plant scientists take measures to minimize these risks. Transgenic crops undergo thorough testing to ensure that possible risks have been considered and addressed.
It is often pointed out that transgenic crops may be safe, but the harm lies in a different factor, such as big corporations/patents/pesticides/etc. Therefore, it bears noting that:
- New crop varieties developed using any of these techniques can be patented.
- Agricultural companies can use any of these techniques when they develop varieties with new traits.
- Crops made to resist pesticides can be developed using other techniques.
Crop modification techniques are different tools that plant scientists have at their disposal. Sometimes, traditional crossbreeding may do the job. But other times, mutagenesis may be needed. Other times, transgenesis will be required. But fearing a method or thinking that a technique should be banned is neither logical nor scientifically sound. As we face challenges including a changing climate and new pests, scientists need all these tools at their disposal to help develop a safe and efficient food supply.