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Crop Wild Relatives for Genetic Diversity and Food Security

Dioscorea esculenta (the lesser yam) is both a wild and a cultivated plant. Some wild yams are in trouble.

Dioscorea esculenta (the lesser yam) is both a wild and a cultivated plant. Some wild yams are in trouble.

An Important Announcement From the IUCN

The International Union for Conservation of Nature (or the IUCN) has announced that more than twenty wild relatives of agricultural crops are in trouble. Some people may wonder why this matters. After all, cultivated crops seem to be all that we need. They have useful features, are abundant in many places, and are a major part of our food supply. Agricultural experts say that we need the wild plants for food security. If cultivated crops are destroyed by a widespread disaster or environmental problem and we have no wild plants to help us, humanity could be in trouble.

It's by no means certain that if a particular disaster kills cultivated crops it will also kill their wild relatives. The wild plants contain a different set of genes, which may be beneficial to them. Although specific genes are vital in order to make a plant useful to humans, genetic diversity can be important with respect to novel features and survival mechanisms. Another advantage offered by wild plants is that they sometimes grow in different areas from the cultivated ones. For these reasons, the wild plants may not be affected by a problem that kills or damages the cultivated crops.

A young Dioscorea villosa (wild yam) growing in the wild in the United States

A young Dioscorea villosa (wild yam) growing in the wild in the United States

Wild relatives of crops are often referred to as crop wild relatives or CWR. They are experiencing problems due to human activity. Habitat for the plants is being destroyed by deforestation and land clearance for agriculture, buildings, and roads.

Wild Wheat, Rice, and Yams Are in Trouble

The IUCN has found that in the wild two types of wheat, three types of rice, and seventeen types of yams are in trouble. The idea of cultivated yams being a staple food may be strange for many North Americans, but they are an important part of the diet in some parts of the world. They feed about a hundred million people in Africa, for example. Wild yams could be important for the health of the cultivated ones.

In much of the world, the word “yam” has a different meaning from its common one in North America. In the grocery stores of Canada and the United States, a yam is an orange-fleshed variety of the sweet potato, or Ipomoea batatas, which is also available as a white-fleshed vegetable. The plant's name is sometimes written as sweetpotato. It belongs to the family Convolvulaceae.

True yams and their wild relatives belong to the family Dioscoreaceae. A few species of wild yams grow in North America, including the Dioscorea villosa shown in the photo above. The plants are vines with heart-shaped leaves. The part that is eaten is a tuber. A tuber (or stem tuber) is a swollen structure in an underground stem that stores starch as food for the plant. The food can also be used by us.

Oryza australiensis is a wild species of rice.

Oryza australiensis is a wild species of rice.

The Problem of Low Genetic Diversity in Crops

Cultivated plants have one feature that could become a major problem: they lack genetic diversity. In general, they have been bred for genes, gene variants, or gene combinations that make them successful crops under current conditions. Less attention has been paid to other characteristics of the plants, including ones that give them resilience to certain problems. The genes in a particular variety of a crop are so similar in different individuals that if an environmental change kills one plant it might kill them all. The stresses might include drought, flooding, fire, pest attacks, diseases, or even sabotage.

Since as a group wild plants have a wider variety of genes, it’s more likely that some members of a species would survive a disaster. These could then be bred for food. It’s also possible that if a stress weakens but doesn’t destroy cultivated plants, breeders could create hybrids between the wild and domesticated plants to provide genes and resilience. Wild plants could act as a reservoir of novel genes for crops. Marie Haga, the executive director of the Crop Trust, says that the wild relatives of crops are "an insurance policy for the world.”

FAO estimates that since the beginning of this (twentieth) century about 75 percent of the genetic diversity of agricultural crops has been lost.

— FAO (Food and Agriculture Organization of the UN)

A Wild and Cultivated Plant Hybrid

Some researchers are already creating hybrids between wild and domesticated crops. It might be possible for hybrids to grow in unusual habitats for cultivated crops, such as deserts or salt marshes. According to the Kew Gardens website, at least one case of hybridization with this result has already occurred.

Helianthus paradoxus is a species of wild sunflower that is classified as threatened in the United States. The plant grows near salt lakes. Researchers have created a hybrid of the wild plant with a cultivated sunflower. This has improved the growth of the cultivated plant in soil containing salt and increased the seed production by the crop growing in that environment.

More Reasons Why Crop Diversity Is Important

Genetic diversity in crops is often referred to as "crop diversity". The goal of the Crop Trust is to preserve and where possible increase crop diversity. The trust is an international nonprofit organization that was established in 2004 by FAO and Biodiversity International. It was once known as the Global Crop Diversity Trust and is sometimes still referred to by this name.

According to the Crop Trust, there are at least six reasons why genetic diversity in crops is important. I've summarized the reasons below.

  1. Providing Food Security: Genetic diversity may help to maintain food security, which is the provision of adequate amounts of safe and nutritious food to an entire population. The food must enable people to lead an active and healthy life.
  2. Adapting to Climate Change: Crops that can grow in a wide variety of climates are needed in order to provide the best chance of maintaining food security in the future.
  3. Decreasing Degradation of the Environment: The growth of suitable plants can reduce environmental degradation in an area. Some varieties of plants may need little or no pesticide treatment, for example, and others may have a deep or widespread root system that reduces soil erosion.
  4. Maintaining the Nutritional Value of Food: Genetic diversity in a crop increases the possibility that some plants will have desirable levels of vitamins, minerals, or other nutrients.
  5. Reducing Poverty: Fighting poverty is a complex topic. Increasing crop diversity may be helpful, however. Farmers who grow desirable crops are more likely to obtain an adequate income. When a food is widely available, it may become more affordable.
  6. Creating Sustainable Agriculture: Successful agricultural techniques resulting from genetic diversity in crops have an increased likelihood of being sustainable.

The Svalbard archipelago is located in the red circle shown in the map above. Norway is the country shaded in red.

The Svalbard Global Seed Vault

Protecting and preserving wild relatives of crops is important. An additional strategy is being used to help humanity recover from a crop disaster, however. The Global Seed Vault in Svalbard, Norway, is a depository for the world's crop seeds. One goal of the depository is to preserve seeds that can produce new crops if the present ones are destroyed by a problem such as climate change, a natural disaster, or a war. Another goal is to store as wide a variety of seeds as possible, thereby preserving the genetic diversity that is still present in cultivated plants.

The seed vault is meant to exist far into the future. Humanity may require specific characteristics in replacement crops at that time. The environment and the required characteristics can't be predicted. Genetic diversity is important in order to increase the likelihood of being able to grow successful and useful crops in the future.

The Seed Vault has the capacity to store 4.5 million varieties of crops. Each variety will contain on average 500 seeds, so a maximum of 2.5 billion seeds may be stored in the Vault.

— The Crop Trust

Location and Creation of the Seed Vault

The Svalbard seed vault was opened by the government of Norway in February, 2008. The building is funded by the Norwegian government and is open to seed deposits from around the world. It's run and/or supported by three organizations: the Norwegian Ministry of Food and Agriculture, the Nordic Gene Resource Centre, and the Global Crop Diversity Trust. The depositors own the seeds and can withdraw them when they wish.

Svalbard is an archipelago located in the Arctic Ocean. It's an unincorporated area but is governed by Norway. The vault is located 1300 km beyond the Arctic Circle in an area containing permafrost. According to the seed vault's website, the vault contains "the seeds of many tens of thousands of varieties of essential food crops".

The seeds of each plant variety in the vault also exist in smaller gene banks around the world. The Svalbard vault has the advantage of being a backup depository located in an isolated area that is protected by the permafrost.

A gene bank stores genetic material. This material may be seeds or frozen cuttings from plants or frozen eggs and sperm from animals. A seed bank stores only seeds, as its name implies.

A Potentially Serious Situation in Svalbard

A potentially serious situation with respect to the Svalbard seed vault occurred in the winter of 2016-2017. Most of the vault is embedded in the ground, as the video above shows. The design of the vault allows the cold ambient temperature to protect the seeds from damage. The winter referred to above was unusually warm, however. Completely unexpectedly, some of the permafrost around the vault melted. As a result, meltwater entered the vault and later froze. Fortunately, the water and ice didn't reach the seeds.

Changes have been made to the vault in order to reduce the risk of damage. The situation is worrying because the Arctic is warming up as the climate changes. The seeds in the vault may one day be very important to humanity. They need to be preserved. In November 2019, Norway's government made the encouraging comment shown below.

The Arctic region is strongly affected by climate change, and with the current upgrade of the vault it will now remain secure even in a warmer and wetter Arctic climate.

— Government of Norway

Seed Banks to Preserve Wild Plants

Since seeds of cultivated plants are being preserved, it might seem logical that those of wild plants should be preserved as well. Some progress has been made in this area.

In Britain, Kew Gardens has published collection guides to help people identify wild plants correctly and gather the seeds. The guides are part of their Crop Wild Relatives Project. The project is run by Kew Gardens and the Crop Trust and is funded by the Norwegian government. It concentrates on crop relatives in the grass family (such as wheat and rice) and those in the legume family (such as peas and lentils).

Collecting the seeds of wild plants could allow cultivated crops to be enhanced in the future. The seeds could also be planted in the wild so that they are exposed to different gene selection processes than the cultivated plants, which would probably be selectively bred by humans.

Crop wild relative seeds are a largely untapped resource for crop improvement, but their potential is immense.

— Laura Jennings, Kew Gardens

Preparing for the Future

All sources of genetic diversity in crops could be vital in the future. The future could be nearer than we think. There has already been one withdrawal from the Svalbard seed vault. Syrian researchers have been unable to continue their research at a gene bank in their country due to the war. In 2015, they used their preserved seeds to set up research stations in other countries. In 2017, they made a new deposit to the seed vault.

In 2020, some significant deposits were made in the seed vault. According to the Minister of Agriculture and Food for Norway, in February, 2020, “representatives from 28 gene banks from around the world braved -20 ºC weather to deposit new seed samples in the Seed Vault”. In addition, the Cherokee Nation in the United States donated “seeds of indigenous maize, bean and squash varieties – crops that make up part of the Cherokees’ cultural heritage.”

We need to think about maintaining, collecting, and preserving crop diversity now. The future is unknown, but there are troubling signs in the present. Climate is changing, and the world's population is increasing. Crops have already died in some parts of the world. It’s important to be prepared for further problems that may occur.

References and Resources

© 2018 Linda Crampton


Linda Crampton (author) from British Columbia, Canada on May 04, 2018:

Hi, Peggy. I hope genetic diversity is preserved. It could be very important for our future.

Peggy Woods from Houston, Texas on May 04, 2018:

I have actually heard about this seed vault. Biodiversity is very important for all the reasons you mentioned in your article. Wild crops are equally important. Hopefully these seeds will be preserved long into the future should they ever be needed.

Linda Crampton (author) from British Columbia, Canada on March 30, 2018:

Thanks for the interesting comment, Natalie. There are definitely a lot of things to think about in the attempt to change genes.

Natalie Frank from Chicago, IL on March 30, 2018:

It seems like when you alter the genes of anything, people, animals or plants, you risk doing something that could destroy them. I think there is a reason that genes play out the way they do in any type of population, plants included, so getting rid of certain characteristics or increasing others can ultimately have very negative effects in the long run. The only example I can think of is roses which are bred for things like appearance, long life when cut, no thorns etc. and not aroma. But their scent is what attracts bees which allows for pollination and reproduction. So hypothetically, if wild roses were destroyed then it seems like cultivated roses would not be far behind unless at least some could be genetically altered back to having a scent or pollination was carried out manually without the help of bees. Maybe I lack enough of a biology background to fully be able to make an accurate analogy but thanks for the education. It was a great read.

Linda Crampton (author) from British Columbia, Canada on January 23, 2018:

Hi, Nadine. I think that heritage seeds are wonderful. I wish they were used more widely. Thanks for the visit.

Nadine May from Cape Town, Western Cape, South Africa on January 23, 2018:

What an interesting article about seed vaults. Learned something about Norway. I only buy what we call heritage seeds for planting herbs and other veggies. They come from people who have inherited these from a family member and they painstakingly collected these seeds. The packets that are for sale in plant nurseries are all genetically modified and I do NOT trust them.

Linda Crampton (author) from British Columbia, Canada on January 23, 2018:

I agree with your opinions, Alex. Gene banks, research, and funding are all very important. As you say, there could be irreparable consequences from genetic erosion in the future.

Alex Anghel from Romania on January 23, 2018:

Gene banks should be a priority for all the countries. Wild relatives don't have the same production potential but they are far more resistant. There are research projects that have as main objectives sustainable conservation of genetic diversity. In my opinion there should be more financing in this area. Genetic erosion is a huge problem and unfortunately could have irreparable consequences.

Linda Crampton (author) from British Columbia, Canada on January 20, 2018:

Thank you very much, Genna. I agree—the relationships in nature are very important.

Genna East from Massachusetts, USA on January 20, 2018:

Fascinating hub, Alicia -- beautifully researched and written. And one that also brings up a favorite theme of mine in nature -- how all things exist in relationship. Humanity needs to become more acclimated with nature, and not so far removed.

Linda Crampton (author) from British Columbia, Canada on January 17, 2018:

Thank you very much for the visit and the comment, Larry.

Larry Rankin from Oklahoma on January 17, 2018:

People just look for biggest yield and don't understand the importance of diversifying crop and animal strain.

Very educational!

Linda Crampton (author) from British Columbia, Canada on January 15, 2018:

Hi, Manatita. Yes, we definitely need to prepare for the future. New problems may appear sooner than we think. Thanks for the visit.

manatita44 from london on January 15, 2018:

We may very well need to go this way big time in 30 years. Perhaps we may be able to preserve human organs too, for many years.

I wonder if you do not have enough feed now to feed all humans.

You tend to show some endless possibilities in your work. Peace.

Linda Crampton (author) from British Columbia, Canada on January 15, 2018:

Hi, Heidi. I hope the seed vault stays safe. It could play a very important role in our future. I hope you have a great week, too.

Linda Crampton (author) from British Columbia, Canada on January 15, 2018:

Hi, Dora. I appreciate the work of the IUCN, too. I hope lots of people pay attention to their news.

Linda Crampton (author) from British Columbia, Canada on January 15, 2018:

Thanks for the comment, Alyssa. I appreciate your visit.

Heidi Thorne from Chicago Area on January 15, 2018:

The seed vault is quite an undertaking! But so needed. I hope they figure out a way to preserve this preservation project, in spite of climate change.

When I was more active in green marketing initiatives with organic, fair trade, and recyclable products, I learned a lot about over-farming issues. Glad you included discussion on those topics.

Thanks for sharing your insight, as always! Have a great week!

Dora Weithers from The Caribbean on January 15, 2018:

Thanks for sharing these important facts, and thanks to the IUCN and other agencies and individuals for paying attention to our food threats and food needs. You encourage us to become aware and not take these provisions for granted.

Alyssa from Ohio on January 15, 2018:

This is such an interesting and important topic. I knew of the seed bank in Norway, but didn't realize there were others around the globe. Thank you for sharing this information!

Linda Crampton (author) from British Columbia, Canada on January 14, 2018:

Hi, Flourish. I agree. The lack of crop diversity worries me not only because of situations that seem likely in the future but also because of situations that we may not be able to predict. Thanks for the visit.

FlourishAnyway from USA on January 14, 2018:

I didn't know there was a seed bank but do recognize how important it is for the future. I'm worried about the impacts of land use and reduced diversity. Some day I think we'll need that seed bank for purposes we may not foresee now.

Linda Crampton (author) from British Columbia, Canada on January 14, 2018:

I agree, Devika. Nature does have many surprises for us! It's always interesting to explore the natural world.

Linda Crampton (author) from British Columbia, Canada on January 14, 2018:

Thank you, Chitrangada. I think it's a matter of concern, too. I hope genetic diversity in crops is preserved.

Devika Primić from Dubrovnik, Croatia on January 14, 2018:

The wild has many surprises for us. I often observe while walking and find many interesting herbs on the way. Your discoveries are unique.

Chitrangada Sharan from New Delhi, India on January 13, 2018:

Great informative article!

It’s good that you have brought attention to this important topic. It’s a matter of concern and good to know that more research is being done regarding this.

Well written and well researched topic. Thanks for sharing!

Linda Crampton (author) from British Columbia, Canada on January 13, 2018:

Hi, Suhail. Thank you for the comment. I enjoy observing wild relatives of crops, too. They could be very useful for us.

Svalbard sounds like an interesting place. I've read about it in relation to the reindeer that live there. I'm very happy that it also contains a seed vault.

Linda Crampton (author) from British Columbia, Canada on January 13, 2018:

I appreciate your comment, Bill. As you say, the ramifications of the problem may affect many people in the future. Some people of today may not realize that the problem exists.

Linda Crampton (author) from British Columbia, Canada on January 13, 2018:

Hi, Mary. The situation seems to be a problem in many places. I think it's vital that we maintain variety in our food crop characteristics or at least have a method to increase its diversity.

Suhail Zubaid aka Clark Kent from Mississauga, ON on January 13, 2018:

When I am hiking with my dog, I take particular interest in the wild cousins of our cultivated crops for their conservation in natural environment. It never occurred to me that we need to save them from the potential danger you have highlighted in this article.

It was good to read about Svalbard as a location in a different context (wild seed vault) that I am used to reading (polar bears).

Very nicely written informative article!


Suhail and my dog.

Bill Holland from Olympia, WA on January 13, 2018:

I actually know quite a bit about this topic. This is one of those things that is vitally important for all of us, but because of ignorance or just a lack of caring, most people know nothing about it...or they know about it but don't do anything about it...but the ramifications of it will hurt generations to come. Thank you for writing about this, Linda. Great job!

Mary Norton from Ontario, Canada on January 13, 2018:

This is interesting that you bring this up. Now, that most of the seeds used before by farmers have been replaced by the more fast yielding cultures variety, this problem comes up. I remembered this with rice. We used to have so many varieties until the seed bank came. It was a help then, but now it is becoming a problem.

Linda Crampton (author) from British Columbia, Canada on January 12, 2018:

I appreciate your comment, Jackie. I hope that more researchers are working on this problem, too. I wish more people were aware of the situation.

Jackie Lynnley from the beautiful south on January 12, 2018:

Disturbing! I sure hope there are more out there working on this problem than we know about, Linda.

You brought to attention something we would never imagine. Important problems to consider.