Training Course: Collecting & Long-Term Conservation of Crop Wild Relative Seeds

In the following Q&A, Dr Eastwood, Crop Wild Relative (CWR) Project Coordinator from Kew’s Millennium Seed Bank (MSB) talks to us about the collecting, protecting and selecting CWR “with the aim of ensuring our major crops can be adapted to grow in our changing climates.”

The “Adapting Agriculture to Climate Change” project is a ten-year project divided into three phases.  In Phase I a Gap Analysis was carried out to indicate where CWR still needed to be collected. In Phase II, the current phase, project leaders – Crop Trust and MSB –work with partners from around the globe to secure high-quality seed collections. Phase III will see the use of CWR material.

1. Following the Gap Analysis results and the successful Training Course in Vietnam, the CWR Project is getting ready for a new capacity building effort — this time in Africa. Please tell us more about this.

Our job now is to work with partners to secure high quality seed-collections across the globe.

We are holding a training course on collecting and conserving crop wild relatives (CWR) in Kampala, Uganda in collaboration with the National Agricultural Research Organisation.  Interest in receiving training was very high and participants will be joining us from 8 African countries.

The week-long training course will take place during the week beginning 11th August and kicks off the African regional work in the project.”

It is important that the skills of seed collecting and storage can be shared. The use of material to plant breeders and farmers depends on the quality of collection and storage. For Kew and the Crop Trust it is wonderful to be strengthening ties with the participant institutions.

2. Tell us about the actual day-to-day training course activities.

The course is a mix of fundamental theory and applied hands-on training.  It is led by experienced experts from the MSB. Participants will learn how to plan collecting trips, assess populations for collection, collect field passport data, and use a drum drying kit and store collections safely, among many other things.

Participants will become familiar with the national Collecting Guides, which the project is providing to all national programs. These include identification tips, fruiting time data and suggested methods for collection.

Field activities will put the knowledge directly into practise. For example: participants will carry out cut tests on seeds to assess whether they are healthy.

3. Once the training week is over, what happens next? 

We are already working with African partner organisations to plan how they will collect their national CWR.

CWR collecting gaps in Africa for the CWR of project priority crops

CWR collecting gaps in Africa for the CWR of project priority crops

The collecting ambition of each country program depends on the number of species in the country and how well they have been collected to date. In total the project aims to collect over 6,000 accessions.

When the participants attending the course return to their countries, they will be directly involved in implementing these national programs.  It is envisaged that the first collecting expeditions will start in the autumn.

4. Once the collecting is done, what then?

The collected and cleaned material will be stored in the national genebank and a sample will be sent to the MSB for long-term safely duplication and for distribution to researchers and pre-breeders.

5. Looking at the bigger picture, please tell us why is it important to go after CWR?

“Food security in the light of climate change is one of the greatest challenges the world faces.” 

We don’t yet understand all the effects this will have so we need to have all options secured. One tool which has been show to contribute is improving crops using CWR.

CWRs have not gone through the domestication bottlenecks that have contributed to the limited genetic diversity within our crops. What’s more, they have continued to evolve in varied environments and climates. And it is known that they hold adaptive traits, some of which are unexpected and can only be discovered through breeding programs.

There is urgency to this work not only because the effects of climate change are already starting to be seen, but because the vital building blocks to allow us to adapt – the CWR – are threatened in their natural environments.

“There is huge pressure on use of land for agriculture, housing and recreation, all of which impacts negatively on biodiversity.”

6. Effects of climate change are predicted to be felt most strongly in sub-Saharan Africa.

Yes, and CWR of Aubergine, Finger Millet, Pearl Millet, Rice and Sorghum – all of which are found in Africa — could be used to adapt agriculture.

Food security is a global issue and no country is self-sufficient for its food.  Thus the CWR project is not just working in Africa, it has a global outlook.  CWR from other regions of the world could also help to improve African agriculture.

7. Can you tell us what other efforts that have been carried out by the CWR project?

Last December a similar training course was carried out for Asian partners in Viet Nam and from this project plans for collecting are well-developed.

Collecting has already started in Portugal, Cyprus and Italy.

The first 100 collections have already been received at the MSB and many more are expected in the autumn.

8. Any last words?

“This project is unusual in its scope. It will not only secure CWR but will start to unlock their potential through pre-breeding programs.”

CWR hold solutions for the future and through the support of the Norwegian government the Royal Botanic Gardens, Kew and the Global Crop Diversity Trust are able to work with partners to leave a legacy of potential for the next generations.

Related Links

Video: Ruth on CWR

Video: Jonas on Collecting

Video: En Español: Nora Castañeda

Video: beyond the gardens

Blog post: seed collecting training in Asia

Blog post: seed drying

Seed Drying for the Successful Long-term Storage of Crop Wild Relatives

Keeping seeds for generations to come

Crop wild relative Vicia hyaeniscyamus may useful traits to make faba bean more resilient (Photo: Colin Khoury)

Crop wild relative Vicia hyaeniscyamus may have useful traits to make faba bean more resilient (Photo: Colin Khoury)

Crop wild relatives are a powerful tool we have to adapt agriculture to climate change and worryingly, many of them are currently threatened and in need of conservation. Crop wild relatives can be credited for traits that make our crops resistant to diseases such as grassy stunt virus in rice and black sigatoka in banana. Crop wild relatives have also been used to increase the yield of wheat and breed drought and salinity tolerance in barley. (See examples here and here).

Crops such as potato, rice, lentil and banana are major food sources for millions of people all over the world and by increasing their genetic diversity and resilience, through the use of crop wild relatives, more people will have access to the food they need. That is why the Global Crop Diversity Trust and Kew’s Millennium Seed Bank are collecting the seeds of crop wild relatives. This 10-year project is aptly called Adapting Agriculture to Climate Change.


Global gap richness of high priority species for all crop gene pools combined (Photo: CIAT).

Global gap richness of high priority species for all crop gene pools combined (Photo: CIAT).

Using the results of a gap-analysis generated by CIAT, partners of the project are collecting crop wild relatives of 29 of most globally important food crops and making them available to breeders so that more resilient varieties will be created.

The project is in the thick of the collecting phase and before long we should have an impressive portfolio of crop wild relatives collected, protected and prepared for the development of new, better adapted, crop varieties. Proper handling of the seeds is important for maximising their longevity in storage. When subjected to certain conditions, seeds can remain in storage for tens and sometimes hundreds of years and still be able to germinate into a living plant. Luckily this means that the seeds can come to our aid against the unforeseen challenges of future.

There are two crucial components to successful seed storage: drying and freezing. If you want to store seeds and delay their germination, you need to keep them dry. Freezing them increases their longevity even further by slowing down metabolic reactions in the cells of the seed.

Seed storage and agriculture

Humans use this adaptation of seed dormancy to their advantage. Since the dawn of agriculture farmers have been safeguarding seeds to ensure the harvest for the following year. Conservation of plant genetic resources, including crop wild relatives, also allows breeders to develop new crop varieties that are tastier or more resistant to disease.

Seed drying

Once seeds have been collected keeping them dry is the number one priority for every seed collector. There are a few tricks of the trade that every good seed collector keeps with them.

1. Bag it up

Seed collectors think carefully about the kind of bag they choose to keep their collections in. Cloth, paper or plastic bags – it depends on what seeds you are collecting. (Read more here)

Image of spiky crop wild relative of oats, Avena sterilis, being put into a paper bag

Spiky crop wild relative of oats, Avena sterilis, being put into a paper bag (Photo: RBG Kew)

2. Keep an eye on the weather

Besides checking to see whether you need sunscreen or your waterproofs, looking up the climate of the region, and even the weather forecast for the day is an essential part of the planning for a successful seed collecting trip. E.g. Some seeds are particularly susceptible to deterioration from moist air conditions, such as those collected during the rainy season. These ‘wet seeds’ need to be dried as soon as possible and this can be done by:

  • spreading them out in a thin layer on some newspaper in the shade
  • raising them off the ground to allow air to circulate beneath
  • repacking them before nightfall to minimise moisture absorption as the
    ambient humidity rises

Every seed counts so we cannot afford to be cavalier with our post-harvest handling!

3. The big blue drum

One way that the Millennium Seed Bank helps partner countries to make high quality seed collections when there is no dry-room nearby is to send them a large, 60 litre, blue drum containing sachets filled with dried-out silica gel.


Image of a Low tech seed drying drum

Low tech seed drying drum (Photo: RBG Kew)

Shipped to partners of the Adapting Agriculture to Climate Change project, it is part of a ready-to-go tool kit for the perfect seed collecting expedition. Dissection kits, hand lenses, herbarium presses, collecting guides, GPS, and a first aid kit are among some of the goodies you will find inside. To find out more about how silica is used to dry seeds read here.


Image of a Collecting guide for the crop wild relatives in Mozambique

Collecting guide for the crop wild relatives in Mozambique (Photo: RBG Kew)





Back at the Seed Bank

Seeds can spend up to 6 months in the dry room, only taken out for the brief time it takes for them to be cleaned and counted. Only when the seeds have reached 15% relative humidity are they ready to go into cold storage in the -20°C seed vault.


Image of the dry room at the Millennium Seed Bank

The dry room at the Millennium Seed Bank (Photo: RBG Kew)


A final word on rebel recalcitrant seeds

Some seeds, such as mango and Coco de Mer, cannot survive the drying and freezing process and are therefore difficult to store. These seeds are known as recalcitrant or unorthodox seeds and at the moment their only hope (for ex situ seed conservation) is cryopreservation in liquid nitrogen.

Related Links

The importance of seed drying for long-term seed storage

The wonders of silica for seed drying

Global Crop Diversity Trust

International Center for Tropical Agriculture

post by Sarah Cody, Millennium Seed Bank Partnership, Kew

Banding together: A global community committed to biodiversity and food security

Written by: Melissa Reichwage and reposted from CIAT

“The challenges for agriculture are vast, but we do have a basic structure to build on in order to find solutions. We do have a functioning global partnership,” said Marie Haga in a presentation to the General Assembly and the Economic and Social Council of the United Nations earlier this month.

Haga leads the Global Crop Diversity Trust, an essential funding mechanism to ensure the long-term conservation and use of crop diversity for food security worldwide. In short, the Trust protects one of the world’s least recognized but most valuable resources: crop diversity, the raw material for improving and adapting crops.


Partners for resilience

The formidable challenge is to ensure food security for a growing population in a more sustainable manner, under the pressures expected due to climate change.

Humanity must develop a resilient agricultural system that can tolerate changing weather conditions, that can deal with new pests and diseases, that does not exacerbate climate change and environmental degradation, and which sustainably produces sufficient and nutritious food.

This entails adapting crops to climate change. To adapt crops researchers utilize the genetic diversity in old crop varieties as well as wild plants related to crops (crop wild relatives) which contain important traits, such as drought tolerance or disease resistance that can be hard to find in modern cultivated varieties.

Achieving resilience requires major research partnership coordination to combine the collective knowledge we have of the types of traits different crops will need under climate change – such as heat, drought, or salinity tolerance – as well as where these traits may be found in diverse genetic resources.

Crop breeders require information and germplasm from multiple sources and countries in order to locate and use these traits to improve crops. No country is self-sufficient in this regard, so global exchange of genetic resources is vital.

The crown jewels of international agriculture

The Center for International Tropical Agriculture (CIAT) maintains a genebank at its headquarters in Colombia. With a total of more than 65,000 plant samples, this facility safeguards the world’s largest collections of beans and cassava along with their wild relatives, as well as tropical forages. These collections conserve a great wealth of the world’s agrobiodiversity and make this diversity available to the global community.

ciat genebank

“Today, thousands of improved crop varieties are growing in farmers’ fields that can trace their roots to CGIAR genebanks,” Haga noted.

Norway – where the Svalbard Global Seed Vault protects the world’s seed samples deep inside a mountain on a remote island – is an important investor in CIAT’s efforts to collect, conserve, and enhance the use of crop wild relatives.

Thanks to contributions from the Government of Norway (MOFA), administered by the Millennium Seed Bank Partnership of the Royal Botanic Garden Kew and the Crop Trust, CIAT is helping to advance a synergistic endeavor – the Crop Wild Relatives project to adapt agriculture to climate change. The project is entering a new phase to build upon existing research, capitalize extensive relationships created with experts worldwide, and to maximize the impact of these resources.

“It’s an honor for CIAT to be a part of this colossal global partnership. Seeds, crops, information, and tools established at the Center are being used all around the world for the benefit of our collective future,” said Colin Khoury, Crop Wild Relatives project staff at CIAT.

Related stories:
CGIAR Consortium partners with Global Crop Diversity Trust to revitalize genebanks
Study on human diets whets the appetite of global media
Just warming up: Cassava isn’t afraid of a changing climate
This crazy world

Photos by Neil Palmer (CIAT).

We’re becoming more similar: trends in global diet and the consequences for food production and health

A study published today in the Proceedings of the National Academy of Sciences of the USA (PNAS) examined how national food supplies have changed over the past 50 years for 98% of the world’s population. The authors find that diets worldwide have become much more similar in composition over the past five decades, relying increasingly on a limited set of major crops for the majority of dietary calories, protein, fat, and weight.

Overall people are consuming more food, and a greater proportion of the diet is comprised of energy dense food (plant and animal sources high in fats, oils, and sugars). The crops that provide a dominant proportion of this diet are major staple cereals such as wheat, rice, and maize, as well as a suite of globally important oil crop commodities, particularly soybean, palm, rapeseed, and sunflower oil. The contribution of these oil crops in particular has risen disproportionately over the past half century.

Crops showing large relative increases or decreases in the global diet. Khoury et al. 2014

Crops showing large relative increases or decreases in the global diet. Khoury et al. 2014

As a result of these dietary changes, regionally important crops have suffered. The study shows significant decreases in the importance of cereals such as sorghum, millets, and rye and root crops such as cassava, sweet potato, and yam. Locally important crops that are not measured on the global scale have suffered the same fate. Without concerted conservation, research and advocacy efforts, the world is in danger of losing a wealth of diverse, adapted alternative crops.

Although changes in diet have occurred worldwide, the areas where food supplies have departed the most significantly from 50 years ago are in Sub-Saharan Africa and in Asia. On average, global diets have increased in similarity by an average of 36%.

The expansion of the global diet and its accompanying production systems has simultaneously increased efficiency and decreased the resiliency of the global food system. Similarities within the food system facilitate technology transfer and food production, which allow for centralized research to impact larger portions of the world. Simultaneously though, these similarities make the global food supply more susceptible to widespread problems such as pests, disease, and climate change, as a greater uniformity of crops are grown over larger areas.

While the availability of more energy dense food has improved food security in some regions in the form of both sufficient quantities and increased nutrients, the increasing homogeneity of contributing crops may contribute further to the occurrence worldwide of diseases associated with over nutrition such as diabetes, heart disease, and some forms of cancer. As over nutrition becomes as important as under nutrition for global public health, maintaining diverse diets could be a key strategy to help the fight against diet related diseases.

Change in dietary composition similarity over time. Khoury et al. 2014

Change in dietary composition similarity over time. Khoury et al. 2014

Addressing the challenges and vulnerabilities created by greater homogeneity in global food supplies will require a combination of scientific research, advocacy, political agreements, and changes in agricultural production. Key steps include: 1) ensure the genetic diversity of major crops through developing and growing a wide range of locally adapted varieties with distinct characteristics, 2) increase the conservation and utilization of diverse genetic resources- including crop wild relatives- that underpin crop diversification, 3) enhance the nutritional quality of major staples for micronutrients, and/or provide micronutrient supplements, 4) encourage a wider range of alternative crops through promotion of the benefits of such crops in the diet and via research in crop development in order to enhance competitiveness, and 5) publicly show the links between crop diversity, diet diversity, and health.

Read the article here.

Khoury CK, Bjorkman AD, Dempewolf H, Ramírez-Villegas J, Guarino L, Jarvis A, Rieseberg LH and Struik PC (2014) Increasing homogeneity in global food supplies and the implications for food security. Proceedings of the National Academy of Sciences of the USA. doi: 10.1073/pnas.1313490111. Available online at:

Project set to improve the resilience of agriculture under climate change with the help of wild genes – new paper released

Plant collectors and crop breeders from around the world have teamed up to collect, protect and prepare the wild relatives of our most important food crops in a form that can be used to create new varieties that are resilient to climate change. The project, jointly run by the Global Crop Diversity Trust and Kew’s Millennium Seed Bank with support from the Government of Norway, is called Adapting Agriculture to Climate Change and focuses on 29 crops; including globally important crops such as wheat, rice and potato as well as crops of major regional importance in the developing world, such as finger millet, sweet potato, cowpea and sorghum.

sweet potatoes. credit: Credit: Tumwegamire, S., International Potato Center (CIP)

sweet potatoes. credit: Credit: Tumwegamire, S., International Potato Center (CIP)

Scientists working on the project released a paper earlier this week emphasising the relevance of the work for food security and outlining the main phases which will lead to the development of these new varieties. Climate change is acknowledged to be one of the biggest threats to food security in the 21st century. Many decades of modern selective breeding, while greatly improving  yield in major crops,  has unfortunately left them low in genetic diversity and therefore vulnerable to stresses such as rising temperatures, drought, and diseases.  One way to introduce genetic diversity, and therefore resilience, in our crops is to include their wild relatives in breeding programs so that the useful traits they contain (e.g. higher yield, disease resistance, drought tolerance) can be passed onto our crops.

The main phases of the project are as follows

  1. identify those crop wild relatives (CWR) that are missing from existing gene bank collections, are most likely to contain diversity of value to adapting agriculture to climate change, and are most endangered;
  2. collect them from the wild and conserve them in gene banks for conservation;
  3. evaluate these and other CWR materials already in collections for useful traits and prepare them for use in crop improvement; and
  4. make the resulting products and information widely available.
bean research. credit: N. Palmer, CIAT

bean research. credit: N. Palmer, CIAT

With the first phase of the project already completed, and the second phase well underway, we will soon have a more comprehensive collection of CWR stored in seed banks as well as more active breeding programs to develop new adapted varieties.

To read the paper in full, click here.

Collecting crop wild relatives- lessons from the field in Vietnam

Elinor Breman, Species Collections Support Officer at Kew’s Millennium Seed Bank (MSB), reports on a training workshop that brought partners from across Asia together to learn about collecting, handling and banking the seeds of their crop wild relatives.

Global food security

Global food security is of growing concern in light of population expansion and climate change predictions. There are around 7,000 plant species used as food crops globally, but only 12 of these account for roughly 80% of global consumption.

Conserving the genetic diversity of the most important food plants is vital for breeding crop plants that are able to face future environmental challenges. The Millennium Seed Bank of the Royal Botanic Gardens, Kew and the Global Crop Diversity Trust have joined forces in a project to collect, conserve and make available for use the genetic diversity in the wild species related to major food crops. The Decision and Policy Analysis group at CIAT is partnering on providing information on collecting priorities.

This project – ‘Adapting Agriculture to Climate Change: Collecting, Protecting and Preparing Crop Wild Relatives’ (CWR Project)- supports national institutes around the world in collecting and safeguarding priority crop wild relatives. Seed Collecting Guides have been developed to provide collectors in the field with as much information as possible about these wild plants, so that they are able to find them and collect their seeds. The Vietnam Seed Collecting Guide contains information for 17 different Crop Wild Relatives, including distant cousins of banana, apple, pigeonpea, aubergine, rice and sweet potato. The collecting guide contains a description of what the target plants look like, when they are going to have ripe seeds, where they are found, and also has some photos to help identification.

Vietnam Seed Collecting Guide: page for banana relative Musa itinerans.
This wild relative of banana is found in evergreen forests and ravines. Unlike cultivated bananas, it has large seeds (up to 7mm) and the skin of the fruit is pink rather than yellow.

Training in Vietnam

Members of RGB Kew’s Seed Conservation Department together with representatives of the Global Crop Diversity Trust headed to Hanoi in Vietnam to lead a training course for delegates from Indonesia, Malaysia, Nepal and Vietnam.

The week-long training course on collecting, handling and long-term conservation of seeds of wild species related to crops was hosted by the Vietnamese Plant Resources Center and funded through the Sfumato Foundation. It provided a thoroughly enjoyable and educational introduction to the world of wild species seed conservation, highlighting the particular challenges that wild species pose, compared to crops, but also how crop and wild species conservation can learn from each other.

In the lecture room, the science behind long-term seed conservation was explained, enabling participants to understand how factors such as temperature, seed moisture and seed development would affect the longevity of seeds in storage. Fieldwork planning was outlined, detailing how to target species and areas for collection, the genetic basis of sampling strategies, and how to use Seed Collecting Guides.

In the field

We then moved from the lecture room to the field to put the theory into practice. In the Ba Vi Mountains National Park, to the west of Hanoi, participants were able to
• assess the quality of potential seed collections
• choose appropriate sampling strategies
• make collections of seeds, herbarium specimens and associated data
• choose appropriate post-harvest seed handling methods

Putting theory into practice – fieldwork in the Ba Vi Mountains National Park: negotiating the terrain; making a herbarium voucher; collecting target species.

The many challenges facing seed collectors in the field soon became apparent. Finding a target species when it was growing in inhospitable terrain or widely dispersed is not always that easy. When you have found it, a plant may have many fruits on it, but how many seeds are in that fruit, and how many of those seeds are fully developed and likely to germinate? The importance of checking seed viability using a seed cut test was demonstrated, together with seed number calculations which determine whether an adequate sample can be collected from the target population without impacting on the wild population’s survival.

The practical session continued the following day when the material collected in the field was cleaned and counted at the Plant Resources Center. Here a variety of species requiring different cleaning techniques were used, and different winnowing methods were shared by participants.

Seed cleaning at the Plant Resources Center, Hanoi

Local Culture

Whilst in Vietnam our hosts from the Plant Resources Center ensured that the course ran smoothly, that everyone was looked after and that we sampled Vietnamese culture. This included introducing participants to the wonders of Vietnamese cuisine and the organisation of an optional excursion after the course had finished to the World Heritage site, Halong Bay. Meal times and the excursion proved an invaluable time for networking among participants. At the end of the week, they left not only with their newly-acquired knowledge of seed collecting, handling and long-term conservation for wild species, but also with new friendships and an air of excitement about participating in the Crop Wild Relatives Project.


Participants and trainers on the training course, Hanoi, Vietnam (Photo: Plant Resources Center, Vietnam)

Agricultural Research Service develops National Inventory of Crop Wild Relatives

An estimated one of every five plant species worldwide is threatened by habitat loss, climate change, invasive species, and other threats. In the United States 30 percent of native plant species are threatened and some of these native species are closely related to crop plants we eat every day.

Through crop breeding, these crop wild relatives (CWR) can provide critical sources of genetic diversity that can provide crops with an array of economically important traits–such as resistance to emerging pests and diseases, increased yield, and better drought tolerance. The use of CWR for these purposes has been expanding in recent decades, and is thought to only continue to grow as breeders tackle the myriad challenges of future crop improvement.

Tripsacum dactyloides, CWR of maize, in Florida

Tripsacum dactyloides, CWR of maize, in Florida

In the U.S. the Agricultural Research Service and collaborating scientists have created a first-of-its-kind inventory for U.S. wild and weedy crop relatives that prioritizes the species by their breeding importance for important food and fiber crops. The Inventory lists the species and their related crops, and gives indications regarding the conservation status as well as the availability of accessions of these species in national genebanks.

Read more about the National Inventory in the January 2014 edition of Agricultural Research.

Filling in the gaps: seed collecting for the future

Sarah Cody explains how gap analysis is helping our partners collect the seed of crop wild relatives (CWR) for a project called ‘Adapting Agriculture to Climate Change’, run jointly by Kew’s Millennium Seed Bank and the Global Crop Diversity Trust.

Climate change is one of the biggest challenges facing modern agriculture and the predictions for increasing temperatures and changes in rainfall pose a big threat to global food security. In response to this global threat, Kew’s Millennium Seed Bank Partnership has joined with the Global Crop Diversity Trust to launch ‘Adapting Agriculture to Climate Change: Collecting, Protecting, and Preparing Crop Wild Relatives’.
This project aims to safeguard the wild relatives of important crop species so that important characteristics are conserved and can be used to improve our crops, breeding in new characteristics to make them more suited to future climates.

Crop plants are especially vulnerable to rising temperatures and climatic change. Unlike animals, they cannot get up and walk away from a stressful environment. They are rooted to the ground and, for the most part, are dependent on humans to collect and sow their seed to complete their life cycles. Because of the domestication process many of our crops are low in genetic diversity and in great danger of being wiped out by pests, diseases and environmental stresses such as drought, flooding and higher temperatures.
Crop wild relatives (plant species that are genetically related to crop species but that have not been domesticated) can contain far greater diversity than their domestic cousins and so may hold increased potential to adapt to crop pests and diseases, adverse weather conditions and longer term changes in climate.

Wild sunflower, Helianthus annuus, brightening up a gloomy sky (Photo: Kasia Stepien)

Wild sunflower, Helianthus annuus, brightening up a gloomy sky (Photo: Kasia Stepien)

One way to improve the resilience of our crop plants is to harness the genetic diversity found in their wild cousins. By introducing CWR into breeding programs, the useful traits they contain, such as high yield and disease resistance, can be passed onto our crops.
Teaming up with the Global Crop Diversity Trust, Kew scientists are supporting countries around the globe in the collection of seeds from the wild relatives of 29 of the most important crop plants, including banana, apple, sunflower and sweet potato as well as crops like sorghum, cowpea and millet, which are staple foods for many people in the poorer parts of the world.

The project focuses on collecting the seeds of plants which are not too distantly related to the crop, ie wild cousins that have retained their genetic diversity and which have a good chance of being successfully crossed with the crop to produce fertile progeny. For the 29 crops in this project the inventory of close crop wild relatives stands at ~450 species.
The first generation of a cross between a crop and its wild relative is unlikely to lead to the perfect supermarket-ready crop. The progeny may have inherited disease resistance or other valuable characteristics from its wild parent, but it will have also inherited many undesirable traits that can only be tamed though repeated back-crossing with the cultivated parent.
This can take years, which is why we need to collect these seeds as soon as possible so we can pass them onto specialist plant breeders (pre-breeders) to start the process of creating new crop varieties that are adapted to climate change.

In order to make quality seed collections we need to know the geographical distribution of the target species and where the gaps in our seed collections occur. To achieve this another project partner, the International Center for Tropical Agriculture (CIAT), is employing a powerful method called gap analysis. This uses location data on herbarium specimens coupled with knowledge of current seed bank holdings to help us prioritise the species and locations of crop wild relatives that are in most need of collection.
Kew’s collections include over 7 million herbarium specimens, such as the specimen of cowpea below, and 5 billion seeds collected from over 40,000 species. The data associated with these collections have been combined with data from other herbaria, genebanks and experts worldwide, and this information is vital to the gap analysis.

Herbarium specimen of Vigna unguiculata (cowpea)

Herbarium specimen of Vigna unguiculata (cowpea)

Herbarium specimens are a valuable record of a plant species in time and space. Fortunately for us, botanists since the 1700s have fastidiously noted down information about their specimens, such as the collection location, the soil type, the climate of the area, the altitude, and other potentially useful information, such as the local name of the plant and how the plant is used by the surrounding community. Today, with the benefit of technology we can use this information in many useful ways and gap analysis is just one of them.
The scientists at CIAT used location data from the herbarium specimens of crop wild relatives to map the places where these plants were originally collected. Then, through climate modelling they were able to extrapolate the data to make predictions of where other populations of the same species are likely to grow. This tells us the expected geographic range of the species and this is then compared with global seed collection data, including that stored in Kew’s Millennium Seed Bank, so we can identify priority locations for seed collection.

The map shows the gap richness of all the high priority species for all crop gene pools combined, and shows which geographic regions around the world are in the greatest need of collecting. South Africa, the Mediterranean, the Near East and Southeast Asia are areas which have high numbers of priority species that we still need to collect. The full results of the gap analysis can be found on the Crop Wild Relatives Global Atlas on the Adapting Agriculture to Climate project website.

Global gap richness of high priority species for all crop genepools combined (Image: CIAT).

Global gap richness of high priority species for all crop gene pools combined (Image: CIAT).

The reality is that many crop wild relatives are poorly collected, and in almost all instances the collections held in gene banks across the world do not represent the full geographic range of the species. This puts crop wild relatives, and therefore our major food crops, in a very vulnerable position, especially since many are threatened in the wild and in danger of going extinct.
The good news is we are now supporting partners across the world to collect their CWR, and thanks to the use of gap analysis we can now focus our resources on the highest priority species and where to collect them in order to fill in the gaps.

Post by Sarah Cody, Kew’s Millennium Seed Bank

Conservation concerns for endemic potato species in Bolivia

Potato is one of the most important food crops in the world, particularly in Bolivia, where the crop is a primary source of nutrition and food security for a population of 10.5 million. Although not commonly served on the dinner table nor grown on farm, the wild relatives of potato are equally important – carrying an array of traits that continually adapt to changing climates.

Bolivia also has many potato wild relatives, of which 21 are endemic to the country. Out of these, at least 16 have shown to have important traits for plant breeding, such as resistance to late blight (Phytophthora infestans), one of the main diseases affecting potato cultivation in Bolivia; resistance to cyst nematodes (Globodera spp.) that attack the roots of the plant; as well as tolerance to various climatic factors such as extreme heat, drought or frost.

But crop wild relatives are increasingly threatened. After collecting new samples, and applying geographic analysis, Bioversity International and PROINPA found that more than 70% of these endemic species could be considered as vulnerable or worse according to the International Union for Conservation of Nature (IUCN) Red List criteria. Many of the locations, where these wild relatives grow, are threatened by habitat destruction, fires and livestock pressure. Threat maps developed by the International Center for Tropical Agriculture (CIAT) helped to identify which areas and which species are endangered by human disturbance.

Bioversity and PROINPA’s study found four endangered species that require special conservation efforts. Their conservation in genebanks is highly varied and some are not conserved at all or with only a few accessions. Conserving these species in genebanks might not suffice anyway – they should also be conserved in situ, in their natural habitat. These are among the species that have demonstrated resistance to several crippling pests and diseases, hence the need to prioritize their conservation.

The study also indicates several areas in the country as target areas to collect potato wild relative germplasm. This information will be of great use to the Bolivian National Institute of Agricultural and Forestry Innovation (INIAF), which currently coordinates the country’s genebanks and germplasm collections.

PROINPA will also be disseminating this information in a national biocultural program that works on the conservation of crop wild relatives. The existing national protected area network has a poor understanding of the distribution of potato wild relatives. The study therefore recommends that national parks and reserves start inventories to keep track of these endemic species, especially where ecological modeling predicts a high number of species to occur.

Read more about the conservation status of endemic wild potato in Bolivia in our recent publication: Endemic wild potato (Solanum spp.) biodiversity status in Bolivia: reasons for conservation concerns’.

Bioversity International is actively involved in the research on Crop Wild Relatives. The national program that our partner PROINPA is involved in, is the ‘Programa Nacional de Biocultura’, led by Vice ministry of Environment, Biodiversity, Climate Change and Forest Development, with financial support of the Swiss Development Cooperation.

Post by Camilla Zanzanaini, Bioversity International

CWR gap analysis results presented at international conference

Earlier this month, the CIAT Crop Wild Relative (CWR) team presented oral papers as part of the American Society of Agronomy (ASA), Crop Science Society of America (CSSA), and Soil Science Society of America (SSSA) International Annual Meetings, Nov. 3-6 in Tampa, Florida, USA.

Our first presentation reported on our research to gather and analyze data on the distributions of the wild relatives of 80 important food crops worldwide. After identifying hotspots of CWR diversity globally and comparing these against what has already been collected and preserved in gene banks, we generated a list of CWR taxa in critical need of future collection for conservation. The information generated is part of the ‘Adapting Agriculture to Climate Change: collecting, protecting, and preparing crop wild relatives’ project led by the Global Crop Diversity Trust in partnership with the Millennium Seed Bank at Kew.

We also presented on a recently completed inventory of CWR in the United States, as well as plans for protecting these plants both in gene banks and in the wild. Although North America isn’t known as a hotspot for crop plant diversity, the inventory uncovered nearly 4,600 CWR in the United States, including close relatives of globally important food crops such as sunflower, bean, sweet potato, and strawberry.

Presenting at the ASA, CSSA, and SSSA meetings was a great opportunity to meet and discuss our most recent results with colleagues from around the world. The presentations sparked questions about the next stages of the project and interest in future participation.

The Crop Science Society of America (CSSA), founded in 1955, is an international scientific society comprised of 6,000+ members with its headquarters in Madison, WI. Members advance the discipline of crop science by acquiring and disseminating information about crop breeding and genetics; crop physiology; crop ecology, management, and quality; seed physiology, production, and technology; turfgrass science; forage and grazinglands; genomics, molecular genetics, and biotechnology; and biomedical and enhanced plants.

CSSA Press Release: Protecting the weedy and wild kin of globally important crops

Blog post prepared by Vivian Bernau, Visiting Researcher (CIAT)


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