At COP15, Sarah Hearne gives an overview of the CGIAR Allele Mining Initiative projects and their potential role in conserving biodiversity and nature. (Photo: Michael Halewood/Alliance of Bioversity International and CIAT)
Prioritizing the protection of biodiversity is an essential part of mitigating and adapting to the effects of climate change and global warming. At the 15th meeting of the Conference of the Parties to the UN Convention on Biological Diversity (CBD) (COP15), held between December 7-19 in Montreal, Canada, emphasis was placed on the important role of nature in meeting the Sustainable Development Goals (SDGs), proposing the adoption of a bold global biodiversity framework that addresses the key drivers of nature loss to secure health and wellbeing for humanity and for the planet.
On December 7, scientists from the International Maize and Wheat Improvement Center (CIMMYT), together with colleagues from CGIAR research centers and the secretariat of the International Treaty on Plant Genetic Resources for Food and Agriculture, presented at a COP15 side event on how Digital sequence information (DSI) is changing the way genetic resources are used in agricultural research and development and implications for new benefit-sharing norms.
The session, organized by the CGIAR Initiative on Genebanks explored the role of DSI to conserve crop and livestock genetic diversity and explore and utilize that diversity in plant and animal breeding programs.
Attendees at the COP15 side event on DSI discover how genetic resources are used in research and development for agriculture. (Photo: Michael Halewood/Alliance of Bioversity International and CIAT)
Carolina Sansaloni, wheat germplasm bank curator and genotyping specialist, illustrated how DSI is being used in the CIMMYT wheat collection to analyze structure, redundancies, and gaps, further detailing how generation and use of DSI to conduct similar analyses within national genebanks in Latin America is being supported through collaborative efforts of CIMMYT and the Alliance of Bioversity and CIAT.
The take-home message was that genetic diversity and germplasm bank collections, when explored at “global scale” with modern tools and diverse partnerships, offer a powerful resource in the efforts to mitigate the impacts of climate change. This potential is only realized through appropriate generation and sharing of DSI generated from collections of many countries of origin.
Farmers gather in a landrace field. Photo: Raqib Lodin/CIMMYT
For thousands of years, farmers in Afghanistan, Turkey and other countries in the region, have been breeding wheat, working closely with the environment to develop traditional wheat varieties known as landraces. Untouched by scientific breeding, landraces were uniquely adapted to their environment and highly nutritious.
As agriculture became more modernised and intensified, it threatened to push these traditional landraces into extinction, resulting in the loss of valuable genetic diversity. Institutions around the world decided to act, forming germplasm collections known as genebanks to safely house these landraces.
In 2009, a team of wheat scientists from the International Maize and Wheat Improvement Center (CIMMYT), the International Center for Agricultural Research in the Dry Areas (ICARDA), the UN Food and Agriculture Organization (FAO), and national partners set off on a five-year expedition across Central Asia to collect as many landraces as they could find. The project, led by FAO Cereal Breeder and former CIMMYT Principal Scientist Alexey Morgunov, was made possible by the International Treaty on Plant Genetic Resources for Food and Agriculture Benefit-Sharing Fund.
The project had two main missions. The first is to preserve landrace cultivation in three countries, Afghanistan, Turkey and other countries in the region by selecting, purifying, and multiplying the landraces and giving them back to farmers. The second is to scientifically evaluate, characterize and use these landrace varieties in ongoing breeding programmes, exchange the information between the countries, and to deposit the seeds in genebanks to safely preserve them for future generations.
The latest results from the project were published in July in the journal Crops. The study, authored by a team of experts from CIMMYT, ICARDA, FAO, and research institutes in Afghanistan, Turkey and other countries in the region, compared the diversity, performance, and adaptation of the collected wheat landraces with modern varieties grown in the regions using a series of field experiments and cutting-edge genomic tools.
“Landraces are very useful from a breeding perspective because they have been cultivated by farmers over thousands of years and are well adapted to climate change, have strong resistance to abiotic stresses and have very good nutritional quality,” said Rajiv Sharma, a CIMMYT senior scientist and co-author of the paper.
“We were interested in seeing how well landraces adapt to certain environments, how they perform agronomically, and whether they are more diverse than modern varieties grown in these regions – as well as give their improved versions back to farmers before they are lost.”
The experiments, which were carried out in 2018 and 2019 in Turkey, and 2019 in Afghanistan, and other countries in the region revealed several physical characteristics in landraces which are no longer present in modern varieties. For example, the team found striking differences in spike and grain colors with landraces more likely to have red spikes and white grains, and modern varieties tending to have white spikes and red grains. This may have adaptive values for high altitudes and dry conditions.
A surprising finding from the study, however, was that landraces were not more genetically diverse than modern landraces.
“Many people thought that when we went from cultivating landraces to modern varieties, we lost a lot of diversity but genetically speaking, that’s not true. When you look at the genomic profile, modern varieties are just as diverse as landraces, maybe even a little bit more so,” said Sharma.
When the team compared landraces and modern varieties on crop performance, the results were mixed with modern wheat varieties outyielding landraces in half of the environments tested. However, they found that the highest yielding landraces were just as good as the best modern varieties – a reassuring finding for farmers concerned about the productivity of their crops.
A new breeding paradigm
The results of the study have important implications for landrace conservation efforts in farmers’ fields and in future breeding strategies. While crossing wheat landraces with modern varieties to develop improved modern varieties is not new, the authors proposed a novel alternative breeding strategy to encourage the continued cultivation of landraces: improving landraces by crossing them with other landraces.
“In order to maintain landraces, we have to make them competitive and satisfy farmers’ needs and requirements. One option is that we breed landraces,” said Sharma.
“For example, you might have a landrace that is very-high yielding but susceptible to disease. By crossing this variety with another landrace with disease-resistant traits you can develop a new landrace better suited to the farmer and the environment. This approach maintains all the features of landraces – we are simply accelerating the evolution process for farmers to replace the very fast disappearance of these traditional varieties.”
This approach has already been used by crop scientists at the University of California, Davis who has successfully developed and registered “heirloom-like varieties” of dry beans. The varieties trace about 98% of their ancestry to landraces but are resistant to the common mosaic virus.
Heirloom food products are becoming increasingly popular with health-conscious consumers who are willing to pay a higher price for the products, garnering even more interest in conserving traditional landraces.
One of the overarching aims of the project was to give wheat landraces back to farmers and let nature take its course. Throughout the mission, the team multiplied and returned landrace seed to over 1500 farmers in communities across Afghanistan, Turkey and other countries in the region. The team also supplied over 500 farmers with improved landrace seed between 2018 and 2019.
Despite the political turmoil facing these countries, particularly Afghanistan, farmers are still growing wheat and the project’s contribution to food security will continue.
These landraces will take their place once more in the farming landscape, ensuring on-farm wheat diversity and food security for future generations.
This research was conducted with the financial assistance of the European Union within the framework of the Benefit-Sharing Fund project “W2B-PR-41-TURKEY” of the FAO’s International Treaty on Plant Genetic Resources for Food and Agriculture.
Denise E. Costich, the recently retired head of the Maize Collection at the Germplasm Bank of the International Maize and Wheat Improvement Center (CIMMYT), sometimes likes to include a Woody Allen quote in her presentations.
“I have no idea what I’m doing,” declares the text over a photo of a befuddled-looking Allen. “But incompetence never stopped me from plunging in with enthusiasm.”
This is perhaps Costich’s tongue-in-cheek way of acknowledging the unusual trajectory that led her to the Germplasm Bank and her zeal for new and interesting challenges. But it is in no way an accurate reflection of the skill, knowledge and humane managerial style she brought to the job.
“CIMMYT requires individuals with a broad set of experiences,” says Tom Payne, head of the Wheat Collection at CIMMYT’s Germplasm Bank. Though she was not trained as a crop scientist, and despite having never worked in a genebank before, Costich’s rich set of professional and life experiences made her an ideal person for the job.
From Ithaca and back again
Born and raised in Westbury, NY, Costich spent much of her childhood on a tree nursery. Her grandfather was the manager, her father became the sales director and eventually her sister also went into the horticulture business. While her experiences on the nursery contributed to an early interest in plants and ecology, the business aspect of the nursery eluded her. “I just can’t sell things. I’m terrible,” Costich says. “But I really do like to study them.”
This studiousness took her to Cornell University in Ithaca, NY, where she initially declared as a wildlife biology major. Her notion of what it meant to “study things” was influenced by her early heroes, primatologists and field biologists Dian Fossey and Jane Goodall. It involved travel. Fieldwork in faraway places. So, when the opportunity arose at the end of her sophomore year to travel to Kenya with Friends World College, Costich didn’t hesitate.
Costich eventually spent four years in Kenya, studying baboons. When she finally returned to Ithaca, she knew two things. Fieldwork was absolutely her thing, and she wanted to pursue a doctorate.
A chance conversation with her housemates in her last semester led to a post-graduation fieldwork stint in the Brazilian Amazon under the supervision of the legendary tropical and conservation biologist, Thomas Lovejoy. But instead of a dissertation topic, she stumbled across a parasite, a case of leishmaniasis and the realization that the rainforest was not the work environment for her.
Unexpected influences and outcomes continued to mark Costich’s career throughout her graduate studies at the University of Iowa. She found her plant not in the field, but while reading a dusty review paper as an exchange student at the University of Wisconsin. Her study of Ecballium elaterium (a wild species in the Cucurbitaceae, or squash, family) did not take her back to the tropics — where most of her peers were working and where she expected to be headed as a grad student — but rather to Spain where, incidentally, she first learned Spanish.
Several years after defending, Costich landed a tenure-track position in the Biology Department at The College of New Jersey. She continued to publish on Ecballium elaterium. Her career appeared to be settling into a predictable, recognizable academic trajectory — one with no obvious intersection with CIMMYT.
Then Costich saw an ad in the Ecological Society of America bulletin for a managing editor position for all of the Society’s journals. Her husband, a fellow biology Ph.D., had been working as an academic journal editor for several years. When Costich saw the ad she immediately drove over to her husband’s office. “I slapped the thing on his desk and said, ‘Here’s your job!’” she recalls.
Costich was right. Soon after, she was on her way back to Ithaca — where the Society’s offices were located — with a family that now included three children. While it was the right move for her family, it came at the cost of her budding academic career. In Ithaca, she soon found herself stuck in the role of itinerant postdoc.
Denise Costich in Spain in 1986, doing fieldwork on Ecballium elaterium with her daughter Mara.
An amazing turn of events
Costich admits that, especially the beginning, the return to Ithaca was tough, even depressing. Her recollections of these years can sound a bit like a game of musical chairs played with research laboratories. As one post-doc or research project wound down, she’d find herself scanning the campus for her next perch. She became very adept at it. “In ten years, I never missed a paycheck,” Costich says.
The turn of the millennium found Costich scanning the horizon yet again. As the days wound down at her latest post, a maize geneticist moved into the lab next door. What started as hallway jokes about Costich jumping ship and joining the maize lab soon turned into an interview, then a job offer.
The job introduced her to nearly everyone at Cornell working in maize genetics. Costich soon found herself managing the Buckler Lab’s work on maize population genetics. Meanwhile, she dabbled in side projects on Tripsacum, a perennial grass genus that is closely related to maize, and managed a major project on switchgrass. At the end of her postdoc, Buckler set to work trying to create a permanent position for her. Once again, Costich’s trajectory was beginning to take a stable, predictable form.
Then CIMMYT scientist Sarah Hearne showed up. “I’d heard through the grapevine — or maybe through the corn field — that the position of manager of the Maize Collection of CIMMYT’s Germplasm Bank was open… and that they were having a hard time trying to find a person for the position,” Costich recalls. She had met Hearne previously and personally knew and had worked with Suketoshi Taba, the pioneering longtime director of the germplasm bank. Naturally the topic emerged as she and Hearne caught up in Ithaca.
Hearne admitted that the search hadn’t yet been successful. “But I know the perfect person for the job,” she added.
“Yeah, who’s that?” Costich asked, not getting the setup.
Denise Costich, the maize collection manager at CIMMYT’s Maize and Wheat Germplasm Bank, shows one of the genebank’s more than 28,000 accessions of maize. (Photo: Luis Salazar/Crop Trust)
A stranger in a strangely familiar land
Costich was not a little surprised by the suggestion. She had never worked at a germplasm bank before. She was finally finding some stability at Cornell.
At the same time, her early dreams of exploring new places through her work, especially the tropics, beckoned. Her youngest son was nearly college-aged. Against the advice of some who had watched her work so hard to establish herself at Cornell, she took the plunge.
By the time she reached the CIMMYT campus in Texcoco, Costich had crisscrossed a good part of the globe, picking up Spanish here, management skills there, a deep knowledge of maize and its biological and cultural evolution yonder. During this life journey, she developed a deep humanism that is all her own.
It all seemed like happenstance, perhaps, until she reached Mexico and — suddenly, counterintuitively — found herself in the field she was perfectly adapted for. “It turned out that being a germplasm bank manager was the perfect job for me, and I didn’t even know it!” Costich says. “I ended up using everything I learned in my entire career.”
That isn’t to say that it was easy, especially at first. Taba, her predecessor, had occupied the post for decades, was a trained crop scientist, and had grown the bank from a regionally-focused collection with 12,000 accessions to the preeminent maize germplasm bank globally with 28,000 accessions, a state-of-the-art storage facility, and a slew of pioneering practices.
Not only had Taba left enormous shoes to fill, during his tenure — as is common in the expansionary phase of many projects — it had been difficult for the bank to keep a full accounting and understanding of all the new material that had been added. According to germplasm bank coordinator Cristian Zavala, by the time Costich joined CIMMYT “we knew very little about the material in our vaults.”
“Taba was primarily a breeder,” Costich says. “I actually think this oscillation between a focus on breeding and a focus on conservation and curation is good for the bank.”
Visiting a newly-built community seed reserve in Chanchimil, Todos Santos Cuchumatanes, Huehuetenango, Guatemala, in 2016. From left to right: Mario Fuentes (collaborator), a member of the community seed reserve staff, Denise Costich, Carolina Camacho (CIMMYT), Miriam Yaneth Ramos (Buena Milpa) and Esvin López (local collaborator).
Visiting one of the oldest community seed reserves in the region, Quilinco, Huehuetenango, Guatemala, in 2016. From left to right: Pedro Bello (UC Davis), Esvin López (local collaborator), Denise Costich, José Luis Galicia (Buena Milpa), Ariel Rivers (CIMMYT) and Miriam Yaneth Ramos (Buena Milpa).
Costich with the winners of the Second Harvest Fair and Largest Mature Ear of Jala Maize Contest in Coapa, in Mexico’s Nayarit state.
Costich (left) measures ears of corn for the Second Harvest Fair and Largest Mature Ear of Jala Maize Contest in Coapa, in Mexico’s Nayarit state in 2019.
Costich (center) shares some comments from the stage at the Second Harvest Fair and Largest Mature Ear of Jala Maize Contest in Coapa, in Mexico’s Nayarit state. To her left is Angel Perez, a participating farmer from La Cofradía, and to her right, Rafael Mier, Director of the Fundación Tortillas de Maíz Mexicana.
A bank for farmers
However, according to Zavala, because of the limited knowledge of much material they were working with, many in the bank’s rank-and-file didn’t fully understand the importance of their work. Morale was mixed. Moreover, despite an assumption that her new job would see her working closely with local smallholders, Costich found that the institution was poorly known by everyday farmers in its host country. Where it was known, associate scientist on innovation and social inclusion, Carolina Camacho, notes, there was an assumption that CIMMYT only worked with hybrid varieties of maize and not the native landraces many smallholders in Mexico depend on.
These became the principal axes of Costich’s work at the bank: curation of backlogged material, staff development, and community outreach.
Thus, when Costich realized that records were being kept in a combination of paper and rudimentary digital formats, she sent Zavala, a promising young research assistant at the time, to an internship at the USDA’s Maize Germplasm Bank Collection in Ames, Iowa, to workshops at CGIAR germplasm banks in Colombia (CIAT) and Ethiopia (ILRI), and to meetings on specialized topics in Germany and Portugal.
Zavala had never left the country before, spoke little English, and remembers being “rebellious” at work. “I needed more responsibility,” he says. “Dr. Denise saw that and helped me grow.” Upon returning from an early trip, Zavala helped implement up-to-date traceability and data management processes, including migrating the genebank’s data onto the USDA’s GRIN-Global platform.
But as Payne points out, Costich’s tenure was never about simple bean — or, in this case, grain — counting. “She sees a more human aspect of the importance of the collections,” he says. The main tasks she set for the bank came to be subsumed into the overarching goal of a fuller understanding of the contents of the bank’s vaults, one that encompassed both their biological and sociocultural importance.
When Costich came across a collection of maize landraces from Morelos state assembled by Ángel Kato in the mid 1960s that conserved the name of the farmer who had donated each sample, she worked with Camacho and graduate student Denisse McLean-Rodriguez to design a study involving the donor families and their communities. McLean-Rodriguez, Camacho and Costich set out to compare the effects of ex-situ versus in-situ landrace conservation in both genetic and socioeconomic terms.
Similarly, when a colleague at INIFAP invited Costich to be a judge at a yearly contest for largest ear of Jala landrace maize in Mexico’s Nayarit state, they soon began discussing how they could contribute more than just their participation as judges to the community. Starting in 2016 Costich was a co-lead on a study of the landrace’s genetic diversity as well as an initiative to rematriate Jala seeds conserved at CIMMYT for over 60 years.
Costich and members of the Maize Collection team hosting Pedro Bello from UC Davis (center, glasses) at the CIMMYT Germplasm Bank in Texcoco, Mexico, for a workshop on seed longevity and conservation techniques.
A genebank is not an island
Genebanks are bulwarks against genetic erosion. But, as Camacho explains, this mission can be understood in both very narrow and very broad senses. The narrow sense focuses on genetic processes per se: the loss of alleles. The broad sense includes the loss of cultural practices and knowledge built and sustained around the cultivation of a given landrace. Through the initiatives the bank has undertaken during her tenure, Costich has tried to demonstrate, both scientifically and in practice, how germplasm collections such as CIMMYT’s can complement, reinforce, and be enriched by the work of smallholders — de facto germplasm conservators in their own right — while contributing to the difficult task of combating genetic erosion in the broad sense.
One gets the sense that in Costich’s view this isn’t about a one-way process of big institutions “helping” smallholders. Rather it’s about collaboration among all the participants in an interdependent web of conservation. As she argued at her recent exit seminar, Costich views germplasm banks as one link in a chain of food security backups that begins at the farm level.
Indeed, Costich’s most recent initiative demonstrated how innovations intended for one link in the chain can travel upwards and find applications at bigger institutions.
Costich recently led an initiative with community seed banks in the Cuchumatanes mountain range of Guatemala to study the use of DryChain technology in post-harvest storage of maize. This experiment showed the enormous benefits that incorporating such technologies could yield for energy-insecure or low-tech family and community seed reserves.
Ultimately, however, the study led to a second experiment at CIMMYT’s tropical-climate station at Agua Fría in Mexico. With advice from collaborators at UC Davis and an industry partner (Dry Chain America), the seed conditioning team retrofitted an old drying cabinet at the station to dry maize without using heat, but rather by forcing air to circulate through sacks of drying beads. Under the direction of Filippo Guzzon, a postdoc and seed biologist working with Costich, the long-term viability of seeds dried using the accelerated technique versus traditional, slower techniques was tested. The study showed no loss in long-term viability using the accelerated drying technique.
Denise Costich, CIMMYT director general Martin Kropff, and the Maize Collection team confer certificates of participation to two visiting interns, Jiang Li (to the left of Kropff), a doctoral student from CAAS, Beijing, China, and Afeez Saka Opeyemi (to the right of Costich), a staff member of the IITA Germplasm Bank in Nigeria.
Costich and the Maize Collection team at the 2018 CIMMYT Christmas party. Filippo Guzzon, seated to the right of Costich, had just been offered a postdoc with the team.
Costich and the Maize Collection team at the 2018 CIMMYT Christmas party.
A very busy retirement
At her exit seminar, Costich was presented a plaque in appreciation of her service at CIMMYT by Kevin Pixley, director of the genetic resources program. Terence Molnar, maize breeder with the Genetic Resources Team, has succeeded Costich as the Maize Germplasm Bank Head.
For some of her close colleagues, however, Costich’s departure is not the end of the road. “This is not a forever goodbye,” Guzzon says. “I will continue to be in touch with my cuatita,” says Camacho, who has also left CIMMYT.
For her part, Costich echoes that this is not a forever goodbye at all. Not to her friends and colleagues, and certainly not to her work. At a socially-distanced, maize-based farewell lunch Costich held just days before her departure, she was still busy weaving social connections and furthering collaborations among maize fanatics of all stripes — from chefs and designers to scientists and policy advocates.
She is already considering taking a part time position at her old lab at Cornell and a return to Tripsacum research. At the same time, she will be a visiting scientist at Mexico’s National Center for Genetic Resources (CNRG), where officially she will be heading up part of an international switchgrass study. Costich is hoping to leverage her tenure at CIMMYT by getting involved in a push to help improve the Mexican national system for plant genetic resources. Additionally, she has recently accepted an invitation from Seed Savers Exchange to join their board and she is looking forward to volunteering her time and expertise to various seed-saving initiatives within that organization and their many collaborators.
Asked what she’s looking forward to tackling in her retirement that isn’t work related, Costich betrays her deep allegiance to the plant world. “I don’t know,” she says, “I’m thinking of starting a big vegetable garden.”
Cover photo: Denise Costich stands for a photo during the inauguration of the CIMMYT Genebank museum in 2019. (Photo: Alfonso Cortés/CIMMYT)
On February 27, 2020, the International Maize and Wheat Improvement Center (CIMMYT) opened a new greenhouse at its research station in Tlaltizapán, in Mexico’s state of Morelos. The Garrison Wilkes Center for Maize Wild Relatives is named after a pioneering scientist in the field of maize genetics.
“The name teosinte refers to a group of wild relatives of maize,” said Denise Costich, manager of the maize germplasm collection at CIMMYT. “The seven members of this group — all in the genus Zea — are more grass-like than maize, produce hard-shelled seeds that are virtually inedible, and are capable of enduring biotic and abiotic stressors better than their crop relative.” Teosintes must be protected, Costich explained, as they possess some desirable qualities that could help improve maize resilience in difficult conditions. Since CIMMYT’s Germplasm Bank is the global source for teosinte seed, the new greenhouse, designed exclusively for the regeneration of teosinte accessions from the bank collection, will ensure that there will always be seed available for research and breeding.
Garrison Wilkes was one of the first scientists to emphasize the importance of the teosintes and their close biological relationship to maize. He spent more than 50 years working on maize conservation in collaboration with CIMMYT. Together with scientists such as Angel Kato, a former CIMMYT research assistant and longtime professor, Suketoshi Taba, former head of CIMMYT’s Germplasm Bank, and Jesus Sanchez, as researchers at the University of Guadalajara, he contributed to the development of the global maize collection of CIMMYT’s Germplasm Bank as it exists today.
(From left to right) Garrison Wilkes, Angel Kato and Jesus Sanchez, study a teosinte population in Los Reyes, near Texcoco, Mexico, in 1992. (Photo: Mike Listman/CIMMYT)
Keeping seeds alive
Teosintes are the wild plants from which maize was domesticated about 7,000 years ago. They are durable, with natural resistance to disease and unfavorable weather, and grow primarily in Mexico, Guatemala, Honduras and Nicaragua. “What makes [teosinte] a wild plant is its seed dispersal. Corn doesn’t disperse its seed — it’s stuck on the cob. To be a wild plant means they can sow their own seed and survive,” explained Wilkes. Keeping these seeds alive could be the key to developing resilient modern maize with the potential to feed millions.
One of the difficulties in growing maize and teosinte in Tlaltizapán to produce seed for global distribution is that the station is surrounded by sugarcane fields. Sugarcane carries a disease called the Sugarcane Mosaic Virus (SCMV), to which maize and teosinte are susceptible, and SCMV-positive seed cannot be distributed outside of Mexico. Additionally, if teosinte and maize are grown in close proximity to one another, it becomes very difficult to control gene flow between them via airborne pollen. Several experiments, ranging from growing the teosinte in pots to monitoring that the maize and teosinte flower at different times, could not fully guarantee that there was no cross-contamination. Therefore, in order to continue to cultivate maize and teosinte within the same station, the CIMMYT Germplasm Bank needed to create an isolated environment.
Garrison Wilkes describes characteristic features of the teosinte grown in the greenhouse. (Photo: Alfonso Cortés/CIMMYT)
On average, the teosinte seed collections in the germplasm bank were nearly 19 years old, and 29% were not available for distribution due to low seed numbers. Researchers needed to find a way to produce more high-quality seed and get started as soon as possible. “My staff and I visited Jesus Sanchez, a world-renowned teosinte expert, and learned as much as we could about how to cultivate teosinte in greenhouses,” explained Costich “We realized that this could be the solution to our teosinte regeneration problem.”
Construction of the new greenhouse began in late 2017, with funding received from the 2016 Save a Seed Campaign — a crowdfunding initiative which raised more than $50,000. Donations contributed to activities such as seed storage, tours and educational sessions, seed collection, seed repatriation and regeneration of depleted seeds. With the new greenhouse, CIMMYT scientists can now breed teosinte without worrying about maize contamination, and prevent the extinction of these valuable species.
CIMMYT holds most of the world’s publically accessible collections of teosinte. “The wild relatives are a small part of our collection, but also a very important part, as they are theoretically the future of genetic diversity,” said Costich.“They have been important in the evolution of the crop. If we lose them, we can’t learn anything more from them, which would be a shame.”
Garrison Wilkes (left) poses with maize producer Ventura Garcia and her family. (Photo: Alfonso Cortés/CIMMYT)
In the early 20th century, Aaron Aaronsohn, a prominent agronomist best known for identifying the progenitor of wheat, began looking for durum wheat landraces in Israel. He traveled to villages across the country, carefully collecting and recording details of the local varieties used in each area.
This task was not without purpose. Aaronsohn recognized that as increasing numbers of settlers like himself came to the territory, the varietal change from the introduction of new and competitive wheat varieties and the rapid intensification of agriculture would soon cause all the traditional structures he had identified to disappear.
Aaronsohn was one of the first to begin collecting germplasm in the region, but others saw the importance of collecting before large-scale change occurred. For example, Russian botanist Nikolai Vavilov gathered samples from Israel on one of his expeditions through the Middle East. By the end of the century, a number of collections had been established, but overall efforts at conservation were fragmented.
“That’s why we say the collection was on the verge of extinction,” explains Roi Ben-David, a researcher at the Volcani Center, Israel’s Agricultural Research Institute (ARO). “There were single accessions in genebanks around the world but no one really gave them special treatment or saw their value. Many were in private collections; others were simply lost.”
When Ben-David and his colleagues began looking for landraces six years ago, even the collection housed at the Israeli Genebank (IGB) was disappointing, with many samples stored in unmarked boxes in sub-optimal conditions. “When we came in nobody was really trying to study what we had and put it together to represent the area’s wheat landscape as it was 100 years ago.”
Long-term efforts to restore and conserve a collection of Israeli and Palestinian wheat landraces (IPLR) have led to the restoration of 930 lines so far, but there are many varieties that cannot be recovered. Therefore, it came as a great surprise to Ben-David when he arrived at the International Maize and Wheat Improvement Center (CIMMYT) headquarters in Mexico and stumbled upon one of the collections presumed lost. “I think it was actually my first week at CIMMYT when I spotted a demonstration plot growing one of the lost varieties — a subset of the Ephrat-Blum collection — and I couldn’t believe it.”
He had heard about this collection from the late Abraham Blum, but had never been able to locate it. “Someone might have moved the seeds, or maybe the box was not well labelled and thrown out. We don’t know, but needless to say it was a very good surprise to rediscover 64 of our missing lines.”
What prompted you and your colleagues to start looking for landraces in Israel?
We began because we recognized local landraces are good genetic resources but unfortunately, we couldn’t find any. It wasn’t so much that they didn’t exist, but the accessions were scattered across the world, mostly in private collections in countries like the USA or Australia. The Israeli Genebank, which sits only two floors above my office, had a few buckets of germplasm but nobody really knew what was inside.
The Middle East and the Fertile Crescent are centers of diversity, not only for wheat but for all crops that were part of the Neolithic revolution 10,000 years ago. They started here – the exact point of origin was probably in what is now southeast Turkey – so we have had thousands of years of evolution in which those landraces dominated the agricultural landscape and adapted to different environments.
Why do you think so much of the collection was lost?
The lines from Israel were lost because their conservation simply wasn’t prioritized. Losses happen everywhere but what was missing in this case was the urgency and understanding of just how important these collections are. Luckily, the current manager of the IGB, who is a fundamental partner in building the IPLR, understood the need to prioritize this and allocated a budget to conserve it as one collection.
What is the value of conserving landraces and why should it be prioritized?
Landraces are an extremely important genetic resource. Wild relatives are the biggest treasure, but breeders are usually reluctant to use them because they are so very different from modern varieties. So landraces form the link between these two, having already been domesticated and developed within farming systems while remaining genetically distinct from the modern. In wheat, they’re quite easy to spot because of how tall they are compared to the semi-dwarf varieties that replaced them in the 20th century.
There are two main reasons why we need to prioritize conservation. First, we believe that the evolution under domestication in this region is important to the community as a whole. Second, it is now a critical time, as we’re getting further from the time in which those traditional lines were in use. The last collection was carried out in the 1980s, when people were still able to collect authentic landraces from farmers but this is just not possible any more. We travelled all over the country but the samples we collected were not authentic – most were modern varieties that farmers thought were traditional. Not everybody knows exactly what they’re growing.
The time factor is critical. If we were to wake up 50 years from now and decide that it’s important to start looking for landraces, I don’t know how much we could actually save.
Are there any farmers still growing landraces in Israel?
When we started looking for farmers who are still growing landraces we only found one farm. It is quite small – only about ten acres shared between two brothers. They grow a variety which is typically used to make a traditional food called kube, a kind of meat ball covered in flour and then then either fried or boiled. If you boil it using regular flour it falls apart, so people prefer to use a landrace variety, which is what the brothers grow and are able to sell for up to six times as much as regular durum wheat in the market. However, they’re not really interested in getting rich; they’re just trying to keep their traditions alive.
How are you and your colleagues working to conserve the existing collection?
There are two approaches. We want to develop is ex-situ conservations to preserve the diversity. As landraces are not always easy to conserve in a genebank, we also want to support in-situ conservation in the field, like traditional farmers have done. Together with the IGB we’ve distributed seed to botanical gardens and other actors in the hope that at least some of them will propagate it in their fields.
Having established the collection, we’re also trying to utilize it for research and breeding as much as possible. So far we’ve characterized it genetically, tested for drought tolerance and other agronomic traits and we’re in talks to start testing the quality profile of the lines.
Did you continue working on this while you were based at CIMMYT?
Yes, this was an additional project I brought with me during my sabbatical. The main success was working with Carolina Sansaloni and the team at the Genetic Resources program to carry out the genotyping. If it were left to my own resources, I don’t think we could have done it as the collection contains 930 plant genotypes and we only had the budget to do 90.
Luckily, CIMMYT also has an interest in the material so we could collaborate. We brought the material, CIMMYT provided technical support and we were able to genotype it all, which is a huge boost for the project. We had already been measuring phenotypes in Israel, but now that we have all the genetic data as well we can study the collection more deeply and start looking for specific genes of interest.
What will happen to the lines you discovered at CIMMYT?
They’ve been sent back to Israel to be reintegrated into the collection. I want to continue collaborating with people in CIMMYT’s Genetic Resources program and genebank to do some comparative genomics and assess how much diversity we have in the IPLR collection compared with what CIMMYT has. Is there any additional genetic diversity? How does it compare to other landraces collections? That is what we want to find out next.
Roi Ben-David is based at Israel’s Agricultural Research Organization (ARO). He works in the Plant Institute, where his lab focuses on breeding winter cereals such as wheat. He has recently completed a one-year sabbatical placement at the International Maize and Wheat Improvement Center (CIMMYT).
CIMMYT’s germplasm banks contain the largest and most diverse collections of maize and wheat in the world. Improved and conserved seed is available to any research institution worldwide.