Let’s talk GMOs: Part 2
Earlier this week I posted part one of the “Let’s talk GMOs” and now it is time for part two. Part two will discuss how and why plants are genetically engineered (GE). As mentioned in part one, in the past I had been opposed to GMOs, but now I realize GMO is a very broad term and to say that none are allowed is a little harsh and in the present day agriculture landscape, the term we should be using more is GE as that refers more specifically to what is happening. Much of this post is based on information from an interview with Dr. Pam Ronald, plant geneticist from University of California, Davis.
Reasons for genetic engineering of plants:
Herbicide Tolerant crops- Seeds are bred by transferring a trait that allows the seed to tolerate an herbicide. The most commonly known herbicide that plants are bred to be resistant to is glycophosphate (Round up). According to Dr. Ronald weeds have been the number one problem for farmers. Planting of herbicide tolerant crops has helped control weeds and decreased the use of more toxic herbicides (like paraquat).
Insecticide Resistant crops- These plants express the BT protein from the soil, Bacillus thuringiensis (BT), which is poisonous to certain insects. This allows farmers to reduce or eliminate insecticide sprays. The USDA reports that US farmers planting BT corn have reduced their chemical insecticide sprays 10 fold over the last 15 years. BT is a spray that has been used by organic farmers for over 50 years.
Resistance to environmental stressors- Seeds are engineered with traits that confer tolerance to environmental stress. Some stressors cause the entire crop to be lost, which would mean lost income for the farmer and lost food for some small villages of the world. In the book “Tomorrow’s Table” that Dr. Ronald wrote with her husband, Raoul Adamchak, they discuss how in small villages in South and SE Asia, entire crops of rice can be lost due to flooding. When this happens it may leave a large number of people without a staple food. With the concerns of world hunger and the importance of nutrition as a concern, a flood resistant rice has been developed is now grown by millions of farmers.
Disease Resistance- Plants have been created to fight off disease that can destroy an entire crop. This technology has helped to save the papaya crop in Hawaii. It is difficult to grow organic Papaya because of virus and the use of GE has improved production in Hawaii. According to Dr. Ronald one of the ways that organic papaya can be grown more successfully is when it is grown with GE papaya surrounding it to stop the spread of disease. Therefore, the GE crop can help provide the organic crop that is desired.
Characteristic Promotion- This is when a seed is engineered to create a desired characteristic. An example of this is the non-browning apple (arctic apple). When someone bites into an apple a substance called polyphenol oxidase (PPO) reacts with polyphenolics in another part of the cell. When the PPO and polyphenolics mix the browning process starts. The non-browning apples are made by silencing the genes that promote PPO products so the fruit does not brown. These genes were identified after the mapping of the apple genome. Benefits of the non-browning apple is that it may lead to less food waste, due to the fact many do not like to eat brown apples and they get thrown out. As a pediatric dietitian I see that another benefit is when children are very sensitive to the characteristics of the foods they eat some children may be more willing to eat apples if they know they will not turn brown. Parents may be more able to pack the apples in a lunch box without the worry of browning.
My goal is to not tell you whether you should be for or against GMOs, but to provide you with the education and resources you need to make an informed decision. GMO is a very broad term and stating that they should be eliminated completely may have detrimental consequences for some people, the environment, and the world. It is encouraged that you look for non-biased information to have your questions answered. Below are some resources that are recommended:
American Society of Plant Biologists- https://aspb.org/
United States Department of Agriculture- https://www.usda.gov/
National Academy of Science- http://www.nasonline.org/
“Fair and Balanced take on GMOS” a podcast by Melissa Joy Dobbins- https://www.soundbitesrd.com/podcast-episode-037-fair-balanced-take-gmos-greg-jaffe/
Brochure on GMOs from the Center for Science in the Public Interest- https://www.fmi.org/docs/default-source/gmo-microsite/straight-talk-on-genetically-engineered-foods.pdf?sfvrsn=10