5 Frankenwheat: Has our goal to breed diversity into wheat created unsafe versions of wheat?
Beatrix Haggard; Sara Loss; Tori Booker; and Sarah Mustain
Introduction
Wheat breeding programs have focused on increasing crop diversity by developing greater resilience to biotic (insects, weeds, and diseases) and abiotic stresses (temperature, water, and nutrients) (Chai et al., 2022; Trethowan, 2014). This need for crop resilience is further illustrated by historical precedent, as wheat improvement was a critical aspect of the Green Revolution, which resulted in semi-dwarf wheat varieties that reduced crop losses from lodging (Chai et al., 2022). Lodging occurs when a crop falls over, and grain cannot be harvested from the ground. In the early 1900s, there were multiple outbreaks of stem rust, stripe rust, and leaf rust (Kolmer, 2005; Roelfs, 1989). The outbreak of black stem rust led to the discovery and then development of tolerant varieties, including the selection of Kanred (a Russian variety) and then the development of Thatcher wheat (Coffey, 1936). Recently, there has been an increased focus on water resources across the globe, and breeding efforts have shifted toward drought tolerance in wheat (Chai et al., 2022). Ongoing environmental and climatic changes, along with the potential for a new disease outbreak, create a constant need to develop new wheat varieties and maintain a diverse pool of genetic material to draw from.
While wheat breeding has worked towards resilience through breeding diversity, there are worries that we have gone too far. With increasing rates of gluten intolerance and celiac disease, concerns have grown about the gluten content of modern wheat varieties (Brouns et al., 2022). Studies have evaluated modern (scientific breeding) vs historic (landrace) wheat varieties to determine whether nutritional differences exist between these two breeding periods, but have found that differences in gluten content are more attributable to variety than to the period in which the wheat was bred (Brouns et al., 2022; Shewry & Hey, 2015). However, the rise in scientific wheat breeding correlates with a rise in diagnoses of human diseases, such as Celiac disease and gluten intolerance. People worry that these health issues are due to higher gluten content or the pesticides used to grow these varieties.
In short, people on both sides of the debate have strong opinions about whether crop breeding efforts have helped overcome stagnant yields and crop losses caused by biotic and abiotic stressors, or whether these efforts have created crops that potentially harm human health due to breeding over the past 100 years. In this simulation, you will take one of these sides. In the next section of this chapter, you will learn more about the importance of breeding for crop resilience, changes in “modern” wheat’s gluten and nutritional status, and the important skills you will gain by participating in this simulation.
Key Terms
Celiac Disease – a bodily response to gluten, which can lead to severe injury of the small intestine due to the inability to process gluten, resulting in a reduced ability to absorb nutrients.
Cisgenic – a plant variety with DNA from another plant of a related species.
Gene Editing – a modern breeding technique, which involves the use of CRISPR-Cas9. This is a guide RNA that can allow a specific part of the DNA to be changed without the addition of foreign DNA. (Not transgenic)
Gene Transformation – a modern breeding technique, which involves the use of Agrobacterium and gene guns to introduce new DNA.
Gluten – a protein found in wheat, barley, and rye. It is a mixture of gliadin and glutenin, which is an important part of flour and helps with a dough’s elasticity and ability to rise.
Heirloom – a plant variety that has undergone traditional (open-pollination) plant breeding, and has been passed down in a region or by a family. Sometimes have an age requirement of at least 50 years.
Intragenic – a plant variety with DNA from another plant of the same species.
Landrace – a plant variety that has developed in a specific region over time and shows adaptations to the region.
Transgenic – a plant variety with DNA from another plant species.
Scientific Wheat Breeding (Modern) – a traditional plant breeding technique, whereby the pollen from one variety is used to pollinate a different variety. This is done by hand in a controlled greenhouse environment.
Overview of the Simulation
This simulation engages you in critical discussions about wheat breeding and gluten content in modern wheat varieties. The chapter begins with an opportunity for you to discuss how the themes of the simulation relate to your own lived experience. You will engage with reading, listening, and research activities to help build your knowledge of debates about crop breeding and crop diversity. You will then take a position on wheat breeding and gluten content by adopting a persona in the role-play phase. After reflecting on the role-play, you will either write a letter to the editor, create an infographic, or write an academic essay about this topic.
As shown below, the simulation has five distinct phases.
| How the simulation works | ||
| Phase | Phase Description | Activities |
| 1 | Activation | Discussion 1 & 2
Reading 1 |
| 2 | Comprehension | Listening 1
Reading 2 Role Assignment / Role Preparation |
| 3 | Simulation | Role Play |
| 4 | Reflection | Debriefing Activity
Critical Reflections |
| 5 | Application | Letter to the Editor, Infographic, or Slideshow |
You will gain a number of important skills as you participate in the simulation. These skills are sequenced from simple tasks, such as defining and describing, to more complex tasks such as synthesizing and evaluating.
- make connections between wheat breeding and gluten status
- define key terms relating to wheat breeding and gluten
- describe the central arguments supporting the ethical use of crop improvement
- make predictions about the future of wheat diversity and gluten content
- summarize issues related to the ethical use of crop improvement to maintain diversity
- synthesize knowledge about biases regarding wheat breeding
- evaluate the positions taken in the simulation
Phase 1: Activation
In this phase of the simulation, you will draw on your background knowledge of wheat breeding and gluten. This will help prepare you for the listening, reading, and research activities in Phase 2 of the simulation. It will also allow you to share your experiences and ideas with your classmates.
Discussion Activity 1
Work in a small group. Discuss the following questions and be ready to share your responses with the class.
- Have you ever consumed wheat?
- Do you know someone who is celiac or gluten intolerant?
- Why does scientific breeding aim to create diversity in wheat varieties?
- What are some potential problems if scientists stopped breeding new wheat varieties?
- How can we improve wheat’s resilience to abiotic and biotic stresses?
- How can scientific breeding address gluten intolerance and celiac disease?
Discussion Activity 2
Choose one of the discussion activities below:
Option 1: Watch the short video Gluten – SciShow and discuss gluten. (Additional Source)
- What is gluten?
- What crops contain gluten?
- What is celiac disease?
- What is the difference between a food allergy and an autoimmune disease?
- Should everyone maintain a gluten-free diet?
Option 2: Go to your own pantry, grocery store, or convenience store, either on or off campus. Read through at least 5 labels containing gluten (wheat, barley, or rye), and find 5 items without gluten. When evaluating the labels, look for terms such as wheat protein, bulgur, matzo, maltose, malt extract, seitan, and brewer’s yeast. These are just a few of the possible terms that may indicate a product contains gluten.
- What are the product names for the 5 gluten-containing items?
- What terms did you find showing that gluten was in a product?
- Did you find a food or drink item that you were not expecting to contain gluten?
- What are the product names for the 5 gluten-free items?
- What ingredients do you think were included to replace the gluten? (This could be alternative grain options like sorghum, oat, rice, etc.)
Reading Activity 1
Read Eating Like the Ancients: Heirloom Grains Return (Johannes, L., 2012) and then answer the following questions.
- What is a historic/heirloom or ancient grain?
- Are historic/heirloom wheats safe for someone who has celiac disease?
- What is one of the oldest ancient grains that is being marketed for consumption?
- How likely would you be to purchase a five-pound bag of the historic/heirloom grain flour for $34.95? Why?
- Are the ancient grains more or less nutritious compared to modern grains?
- Are there ancient grains that would be safe for someone with celiac disease to consume? If so, list three other ancient grains.
Phase 2: Comprehension
The purpose of this phase is to help you expand your knowledge of the debates around wheat breeding and gluten content in wheat. You will listen to one presentation and read one text. The presentation will provide you with information about the current wheat trends in Oklahoma and the future of wheat breeding. For Reading 2, you will write a descriptive summary of the text.
Listening Activity 1
Listen to the following podcast from Red Dirt Agronomy and then answer the following questions: Fungicides, old varieties, and new hopes – Red Dirt Agronomy Episode 310
(0:00-1:51)
1. Who is the main person interviewed?
2. Who else talks during the podcast?
(2:20-4:20)
3. What was the range of wheat yield that was harvested around Elk City in western Oklahoma (in bushels/acre)?
4. Were the yields in western Oklahoma good yields?
5. What is test weight? What properties impact test weight according to the podcast?
(10:10-15:30)
6. What was an initial major disease that was found this year in wheat?
7. What does “resistance” mean? What is the difference between reproductive (adult-plant) resistance and all-season resistance?
8. What time of year is Oklahoma wheat prepared for disease infection?
(17:05-19:51)
9. Why is having a heavy disease year important for a breeding program?
10. It was stated that, in a normal year, wheat breeders would advance 40% of a plant nursery, but this year they will be advancing 10% of the nursery. Why does he say that cutting back too much can make the breeding program look like a “utility pole”? What is meant by “they had to do this so that the breeding program does not look like a “utility pole” with regards to diversity in the wheat breeding program?
11. How are high environmental or disease stress helpful to continue working with diversity in a breeding program?
(41:00-46:53)
12. Up to this point, Brett Carver has focused on discussing breeding for disease resistance. What are some other breeding goals he discusses in this section?
13. Which one does he think we should work on first? How do you know?
Reading Activity 2
Choose one of the two journal articles to answer the following summary prompt:
- New insights into wheat toxicity (Ribeiro et al., 2016), and then write a summary using the prompt provided.
Summary Prompt: Based on the reading, provide a brief overview of the potential that wheat breeding has resulted in more toxic wheat (word limit: 100-200 words). Then, summarize how wheat diversity could help develop a safer wheat for celiac consumption (word limit: 100-200 words).
Or,
- Relationships between the Contents of Bioactive Components in Grain and the Release Dates of Wheat Lines in the HEALTHGRAIN Diversity Screen (Shewry et al., 2011), and then write a summary using the prompt provided.
Summary Prompt: Based on the reading, provide a brief overview of the potential that wheat breeding has resulted in more toxic wheat due to gluten proteins (word limit: 100-200 words). Then, summarize how other phytochemicals were impacted when the wheat lines were developed (word limit: 100-200 words).
Phase 3: Simulation
In this phase, you will be assigned a role in a simulated discussion event (e.g., a 45-minute panel discussion). It is important that you understand the context and your role to prepare for the role-playing.
The Context
University dining services is currently evaluating its contract for wheat flour used in its facilities. There are people across the university who are concerned about gluten in modern wheat varieties, and they would like the university dining facilities to purchase heirloom or landrace wheat varieties. The university wheat breeder maintains that modern wheat varieties are not more harmful than heirloom or landrace wheat varieties when comparing gluten content.
Agenda
Should dining services only purchase heirloom or landrace wheat flour?
Roles
You will be assigned a role to play in this phase of the simulation. There are five participant roles on each side of the debate and one moderator role.
Moderator: Dining Service Director
Description
- Your task is to introduce the issue at the beginning of the panel discussion, welcome the participants, and moderate the discussion. Allow every participant (role) about 3-5 minutes to talk and make sure that everyone gets a turn to express their opinion. During the presentation, jot down any questions you have. You may ask one to two questions after the presentation to make sure you understand each group’s (for or against) viewpoint. The moderator role can be played by students or the instructor of the course.
In Favor of Only Using Historic Wheat Flour
Role 1. President of a Non-GMO Student Organization
Description
- You are against your university participating in modern wheat breeding programs due to concerns about the long-term consequences for crop genetic diversity. You are worried about the impact of the modern breeding process.
Potential Sources:
- https://www.heritagegraintrust.org/what-are-heritage-grains
- https://sustainablefoodtrust.org/news-views/heritage-grains-climate-resilient-crops/
Role 2. Assistant Professor in Animal Science
Description
- You are against the use of modern wheats. While traveling in Europe, you were able to consume wheat on a daily basis with no stomach issues. This has led you to the conclusion that there is an issue with wheat in the United States.
Potential Sources:
Role 3. Graduate Student Researcher
Description
- You are against the use of modern wheat varieties due to the use of pesticides in wheat production systems.
Potential Source:
Role 4. Concerned Alum
Description
- You are in favor of using historic/heirloom wheat varieties because they can provide healthier options for students on campus.
Potential Source:
Role 5. Local CSA Farmer
Description
- As a local Community Supported Agriculture (CSA) farmer, you see the value that can be found for local farmers in the region. Small-scale farmers are more likely to grow and sell historic/heirloom varieties, and this could be an important opportunity throughout the state.
Potential Sources:
- Opinion | How An Innovative Grain CSA Encourages Sustainable Food Systems (food tank)
- It all started with a jar of ancient wheat (Farm Week now)
Against Only Using Historic Wheat Flour
Role 6. Concerned alum
Description
- You are against your Alma Mater only sourcing heirloom/landrace wheat flour. You would like dining services to showcase wheat that was developed by your university.
Potential Source:
Role 7. Student president of the agronomy club
Description
- You are against the sole use of heirloom/landrace wheat varieties in dining services. You help your parents grow wheat, and you know that modern breeding has not increased the amount of gluten found in current wheat varieties.
Potential Source:
Role 8. Assistant Professor in Crop Science
Description
- You are against the use of historic wheat varieties due to reduced yields compared to modern wheat varieties.
Potential Source:
Role 9. A student concerned with the increased cost of food
Description
- You are against historic wheat flour due to rising food costs. Many students already struggle to afford nutritious food, and introducing more expensive flour options would exacerbate food insecurity on campus.
Potential Source:
Role 10. Dining services purchasing staff
Description
- You are against the sole use of historic wheat flour due to the lack of availability in the supply chain. You can source whole-grain products, but you cannot guarantee the source of the flour used in the products. The average cost of general wheat flour is $0.51/pound, while the average price for historic wheat is $2.50/pound.
Potential Sources:
Phase 4: Reflection
In this phase, you should evaluate the positions taken in Phase 3. In a small group, complete the debriefing and critical reflection activities found below. This phase provides time and space to further reflect on the topics discussed, the way the arguments were framed, and how you can expand on certain aspects.
Debriefing Activity: In small groups, discuss the following questions. Be prepared to share your thoughts with the whole class.
- What did you think about the topic for this simulation? Were you already familiar with it?
- Was it easy or difficult to create an argument for your side of the issue? Why?
- What did you think of your role in the simulation? Did you personally agree or disagree with your role’s required stance on the issue?
Critical Reflection Activity
In small groups, discuss the following questions. Be prepared to share your thoughts with the whole class.
- Did any of the participants/ groups make particularly persuasive arguments? If so, which one/s? What made the arguments more persuasive?
- Did any of the participants/groups make arguments that you thought were weak? If so, what were the arguments? What made them weak?
- Which individual participant did you find the most knowledgeable / most persuasive in the role play? Why?
- Which group did you find most persuasive? Why?
Phase 5: Application
The purpose of this phase is to showcase your ability to expand on what you have learned through the chapter. When developing one of the options below, you are showcasing your ability to take a stance on a topic and persuade a group to your side of the argument.
OPTION 1: Letter to Editor
You will write an opinion letter to the editor of your university newspaper after hearing both sides of the arguments for and against the sole use of historic/heirloom wheat in dining services.
Prompt: Write an opinion letter to the university newspaper editor either in favor of or against the exclusive use of historic or heirloom wheat in dining services. Your letter should persuade students, faculty, and administrators to support your perspective, drawing on evidence from the simulation roles and outside sources. Your letter should be 300–500 words.
OPTION 2: Infographic
You are trying to raise awareness of this topic and want to create infographics or posters to place on your campus to help people better understand your side of the wheat debate.
Prompt: Using a graphic design tool such as Canva or Adobe Express, create an infographic or poster that incorporates images, graphics, and text to support your position in the wheat debate.
OPTION 3: Short Presentation
You are trying to persuade your student club about this topic. This presentation will be delivered at your next student club meeting.
Prompt: Using Microsoft PowerPoint or another presentation software, develop a five-slide argumentative presentation on your position in the Frankenwheat debate, presenting evidence and reasoning to support your side of the debate.
References
Brouns, F., Geisslitz, S., Guzman, C., Ikeda, T. M., Arzani, A., Latella, G., … & Shewry, P. R. (2022). Do ancient wheats contain less gluten than modern bread wheat, in favour of better health?. Nutrition bulletin, 47(2), 157-167.
Chai, Y., Pardey, P.G., Silverstein, K.A.T. (2022). Scientific selection: A century of increasing crop varietal diversity in US wheat. PNAS, 119(51), e2210773119. https://doi.org/10.1073/pnas.2210773119
Coffey, W.C. (1936). Thatcher Wheat. University of Minnesota, Bulletin 325.
Dempewolf, H., Krishnan, S., & Guarino, L. (2023). Our shared global responsibility: Safeguarding crop diversity for future generations. Proceedings of the National Academy of Sciences of the United States of America, 120(14), e2205768119. https://doi.org/10.1073/pnas.2205768119
Khoury, C.K., Brush, S., Costich, D.E., Curry, H.A., de Haan, S., Engels, J.M.M., Guarino, L., Hoban, S., Mercer, K.L., Miller, A.J., Nabhan, G.P., Perales, H.R., Richards, C., Riggins, C. and Thormann, I. (2022). Crop genetic erosion: understanding and responding to loss of crop diversity. New Phytol, 233: 84-118. https://doi.org/10.1111/nph.17733O
Kolmer, J. A. (2005). Tracking wheat rust on a continental scale. Current opinion in plant biology, 8(4), 441-449.
Roelfs, A.P. (1989). Epidemiology of the Cereal Rusts in North America. Canadian Journal of Plant Pathology, 11:1, 86-90, DOI: 10.1080/07060668909501153
Shewry, P. R., & Hey, S. J. (2015). The contribution of wheat to human diet and health. Food and energy security, 4(3), 178-202.
Trethowan, R.M. (2014). Delivering drought tolerance to those who need it: from genetic resource to cultivar. Crop & Pasture Science, 65, 645-654. http://dx.doi.org/10.1071/CP13401
