Wheat blast is a fast-acting and devastating fungal disease that threatens food safety and security in tropical areas in South America and South Asia. Directly striking the wheat ear, wheat blast can shrivel and deform the grain in less than a week from the first symptoms, leaving farmers no time to act.
The disease, caused by the fungus Magnaporthe oryzae pathotype triticum (MoT), can spread through infected seeds and survives on crop residues, as well as by spores that can travel long distances in the air.
Magnaporthe oryzae can infect many grasses, including barley, lolium, rice, and wheat, but specific isolates of this pathogen generally infect limited species; that is, wheat isolates infect preferably wheat plants but can use several more cereal and grass species as alternate hosts. The Bangladesh wheat blast isolate is being studied to determine its host range. The Magnaporthe oryzae genome is well-studied but major gaps remain in knowledge about its epidemiology.
The pathogen can infect all aerial wheat plant parts, but maximum damage is done when it infects the wheat ear. It can shrivel and deform the grain in less than a week from first symptoms, leaving farmers no time to act.
Where is wheat blast found?
First officially identified in Brazil in 1985, the disease is widespread in South American wheat fields, affecting as much as 3 million hectares in the early 1990s. It continues to seriously threaten the potential for wheat cropping in the region.
In 2016, wheat blast spread to Bangladesh, which suffered a severe outbreak. It has impacted around 15,000 hectares of land in eight districts, reducing yield on average by as much as 51% in the affected fields.
Wheat-producing countries and presence of wheat blast.
How does blast infect a wheat crop?
Wheat blast spreads through infected seeds, crop residues as well as by spores that can travel long distances in the air.
Blast appears sporadically on wheat and grows well on numerous other plants and crops, so rotations do not control it. The irregular frequency of outbreaks also makes it hard to understand or predict the precise conditions for disease development, or to methodically select resistant wheat lines.
At present blast requires concurrent heat and humidity to develop and is confined to areas with those conditions. However, crop fungi are known to mutate and adapt to new conditions, which should be considered in management efforts.
How can farmers prevent and manage wheat blast?
There are no widely available resistant varieties, and fungicides are expensive and provide only a partial defense. They are also often hard to obtain or use in the regions where blast occurs, and must be applied well before any symptoms appear — a prohibitive expense for many farmers.
The Magnaporthe oryzae fungus is physiologically and genetically complex, so even after more than three decades, scientists do not fully understand how it interacts with wheat or which genes in wheat confer durable resistance.
Researchers from the International Maize and Wheat Improvement Center (CIMMYT) are partnering with national researchers and meteorological agencies on ways to work towards solutions to mitigate the threat of wheat blast and increase the resilience of smallholder farmers in the region. Through the USAID-supported Cereal Systems Initiative for South Asia (CSISA) and Climate Services for Resilient Development (CSRD) projects, CIMMYT and its partners are developing agronomic methods and early warning systems so farmers can prepare for and reduce the impact of wheat blast.
CIMMYT works in a global collaboration to mitigate the threat of wheat blast, funded by the Australian Centre for International Agricultural Research (ACIAR), the CGIAR Research Program on Wheat (WHEAT), the Indian Council of Agricultural Research (ICAR) and the Swedish Research Council (Vetenskapsrådet). Some of the partners who collaborate include the Bangladesh Wheat and Maize Research Institute (BWMRI), Bolivia’s Instituto Nacional de Innovación Agropecuaria y Forestal (INIAF), Kansas State University and the Agricultural Research Service of the US (USDA-ARS).
More than 11,000 scientists signed on to a recent report showing that planet Earth is facing a climate emergency and the United Nations warned that the world is on course for a 3.2 degree spike by 2100, even if 2015 Paris Agreement commitments are met.
Agriculture, forestry, and land-use change are implicated in roughly a quarter of global greenhouse gas emissions.
Agriculture also offers opportunities to mitigate climate change and to help farmers — particularly smallholders in developing and emerging economies who have been hardest hit by hot weather and reduced, more erratic rainfall.
Most of CIMMYT’s work relates to climate change, helping farmers adapt to shocks while meeting the rising demand for food and, where possible, reducing emissions.
Family farmer Geofrey Kurgat (center) with his mother Elice Tole (left) and his nephew Ronny Kiprotich in their 1-acre field of Korongo wheat near Belbur, Nukuru, Kenya. (Photo: Peter Lowe/CIMMYT)
Climate-resilient crops and farming practices
53 million people are benefiting from drought-tolerant maize. Drought-tolerant maize varieties developed using conventional breeding provide at least 25% more grain than other varieties in dry conditions in sub-Saharan Africa — this represents as much as 1 ton per hectare more grain on average. These varieties are now grown on nearly 2.5 million hectares, benefiting an estimated 6 million households or 53 million people in the continent. One study shows that drought-tolerant maize can provide farming families in Zimbabwe an extra 9 months of food at no additional cost. The greatest productivity results when these varieties are used with reduced or zero tillage and keeping crop residues on the soil, as was demonstrated in southern Africa during the 2015-16 El Niño drought. Finally, tolerance in maize to high temperatures in combination with drought tolerance has a benefit at least twice that of either trait alone.
Wheat yields rise in difficult environments. Nearly two decades of data from 740 locations in more than 60 countries shows that CIMMYT breeding is pushing up wheat yields by almost 2% each year — that’s some 38 kilograms per hectare more annually over almost 20 years — under dry or otherwise challenging conditions. This is partly through use of drought-tolerant lines and crosses with wild grasses that boost wheat’s resilience. An international consortium is applying cutting-edge science to develop climate-resilient wheat. Three widely-adopted heat and drought-tolerant wheat lines from this work are helping farmers in Pakistan, a wheat powerhouse facing rising temperatures and drier conditions; the most popular was grown on an estimated 40,000 hectares in 2018.
Climate-smart soil and fertilizer management. Rice-wheat rotations are the predominant farming system on more than 13 million hectares in the Indo-Gangetic Plains of South Asia, providing food and livelihoods for hundreds of millions. If farmers in India alone fine-tuned crop fertilizer dosages using available technologies such as cellphones and photosynthesis sensors, each year they could produce nearly 14 million tons more grain, save 1.4 million tons of fertilizer, and cut CO2-equivalent greenhouse gas emissions by 5.3 million tons. Scientists have been studying and widely promoting such practices, as well as the use of direct seeding without tillage and keeping crop residues on the soil, farming methods that help capture and hold carbon and can save up to a ton of CO2 emissions per hectare, each crop cycle. Informed by CIMMYT researchers, India state officials seeking to reduce seasonal pollution in New Delhi and other cities have implemented policy measures to curb the burning of rice straw in northern India through widespread use of zero tillage.
Farmers going home for breakfast in Motoko district, Zimbabwe. (Photo: Peter Lowe/CIMMYT)
Measuring climate change impacts and savings
In a landmark study involving CIMMYT wheat physiologists and underlining nutritional impacts of climate change, it was found that increased atmospheric CO2 reduces wheat grain protein content. Given wheat’s role as a key source of protein in the diets of millions of the poor, the results show the need for breeding and other measures to address this effect.
CIMMYT scientists are devising approaches to gauge organic carbon stocks in soils. The stored carbon improves soil resilience and fertility and reduces its emissions of greenhouse gases. Their research also provides the basis for a new global soil information system and to assess the effectiveness of resource-conserving crop management practices.
CIMMYT scientist Francisco Pinto operates a drone over wheat plots at CIMMYT’s experimental station in Ciudad Obregon, Mexico. (Photo: Alfonso Cortés/CIMMYT)
Managing pests and diseases
Rising temperatures and shifting precipitation are causing the emergence and spread of deadly new crop diseases and insect pests. Research partners worldwide are helping farmers to gain an upper hand by monitoring and sharing information about pathogen and pest movements, by spreading control measures and fostering timely access to fungicides and pesticides, and by developing maize and wheat varieties that feature genetic resistance to these organisms.
Viruses and moth larvae assail maize. Rapid and coordinated action among public and private institutions across sub-Saharan Africa has averted a food security disaster by containing the spread of maize lethal necrosis, a viral disease which appeared in Kenya in 2011 and quickly moved to maize fields regionwide. Measures have included capacity development with seed companies, extension workers, and farmers the development of new disease-resilient maize hybrids.
The insect known as fall armyworm hit Africa in 2016, quickly ranged across nearly all the continent’s maize lands and is now spreading in Asia. Regional and international consortia are combating the pest with guidance on integrated pest management, organized trainings and videos to support smallholder farmers, and breeding maize varieties that can at least partly resist fall armyworm.
New fungal diseases threaten world wheat harvests. The Ug99 race of wheat stem rust emerged in eastern Africa in the late 1990s and spawned 13 new strains that eventually appeared in 13 countries of Africa and beyond. Adding to wheat’s adversity, a devastating malady from the Americas known as “wheat blast” suddenly appeared in Bangladesh in 2016, causing wheat crop losses as high as 30% on a large area and threatening to move quickly throughout South Asia’s vast wheat lands.
A community volunteer of an agricultural cooperative (left) uses the Plantix smartphone app to help a farmer diagnose pests in his maize field in Bardiya district, Nepal. (Photo: Bandana Pradhan/CIMMYT)
Partners and funders of CIMMYT’s climate research
A global leader in publicly-funded maize and wheat research and related farming systems, CIMMYT is a member of CGIAR and leads the South Asia Regional Program of the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS).
CIMMYT receives support for research relating to climate change from national governments, foundations, development banks and other public and private agencies. Top funders include CGIAR Research Programs and Platforms, the Bill & Melinda Gates Foundation, Mexico’s Secretary of Agriculture and Rural Development (SADER), the United States Agency for International Development (USAID), the UK Department for International Development (DFID), the Australian Centre for International Agricultural Research (ACIAR), Cornell University, the German aid agency GIZ, the UK Biotechnology and Biological Sciences Research Council (BBSRC), and CGIAR Trust Fund Contributors to Window 1 &2.
The US delegation stands for a group photo next to the sculpture of Norman Borlaug at the global headquarters of CIMMYT. (Photo: Eleusis Llanderal/CIMMYT)
The existence of the International Maize and Wheat Improvement Center (CIMMYT) marks one of the longest and strongest bilateral relationships between Mexico and the United States of America. Beginning with a pilot program sponsored by the Mexican government and the Rockefeller Foundation in the 1940s, it would officially become CIMMYT in 1966, with many examples of strong collaboration between both countries throughout over 50 years of history.
United States Under Secretary of Agriculture for Trade and Foreign Agricultural Affairs Ted McKinney and dozens of other U.S representatives were officially introduced to this legacy when they visited CIMMYT on November 8, 2019.
The director of the Genetic Resources program, Kevin Pixley (left), gives a tour of the recently remodelled Germplasm Bank museum to US Under Secretary McKinney (second from left). (Photo: Eleusis Llanderal/CIMMYT)
“This is a place I’ve wanted to visit for a very long time,” McKinney stated as he first laid eyes on the CIMMYT offices, “the historical CIMMYT.”
After photos and a quick tour of the museum, McKinney talked to CIMMYT Director General Martin Kropff over Skype. They bonded over their respect for Norman Borlaug and his legacy, especially as McKinney had known him and later his granddaughter Julie personally while the two men worked at Dow Agrosciences.
Kropff gave a presentation on CIMMYT’s impact on agriculture in the United States. McKinney was amazed at how much of CIMMYT’s wheat research benefits farmers in the United States, and expressed enthusiasm for further cooperation. “We’re ready, willing and able to help in any way,” he stated.
The director of the Integrated Development program and regional representative for the Americas, Bram Govaerts, presented on CIMMYT’s work with the United States. Mark Rhoda-Reis, Bureau Director of the Wisconsin Department of Agriculture, was pleased to learn that CIMMYT has been working with the University of Wisconsin-Madison on drought-tolerant maize.
The US Under Secretary of Agriculture for Trade and Foreign Agricultural Affairs, Ted McKinney (center), speaks during one of the sessions at CIMMYT. (Photo: Eleusis Llanderal/CIMMYT)
The group then split off into two groups for tours of the wheat fields and the CIMMYT germplasm bank. The delegation participated in a series of roundtable discussions on various topics such as climate change, sustainable agri-food systems, and the delegates’ objectives and needs related to agriculture in their respective states. A frequent topic was the dilemma of a public with a growing fear of technology, though technology is indispensable in the growth of the science of agriculture. “Research and education is the future of agriculture,” said one of the representatives.
The director of the Genetic Resources program, Kevin Pixley (center), shows some of the genetic materials at CIMMYT’s Germplasm Bank to US Under Secretary McKinney (top-left). (Photo: Eleusis Llanderal/CIMMYT)
At the closing of their visit, the delegation was eager to spread their newfound knowledge about CIMMYT’s work and legacy. “I’m just so impressed with the work done here… the representation of all the countries in this facility is outstanding!,” said Chris Chin, Director of the Missouri Department of Agriculture.
“I was blown away. [CIMMYT] is so valuable to every country in the world,” stated Ignacio Marquez, a representative from the Washington State Department of Agriculture.
Kanwarpal S. Dhugga, a Principal Scientist at the International Maize and Wheat Improvement Center (CIMMYT) who specializes in biotechnology, has been elected a Fellow of the American Association for the Advancement of Science (AAAS), Section on Biological Sciences, in recognition of his invaluable contributions to science and technology.
Announced by AAAS on November 26, 2019, the honor acknowledges among other things Dhugga’s leading research on plant cell wall formation, with applications including their role in lodging resistance and in producing high-value industrial polymers in maize and soybean, and the assimilation, transport, and metabolism of nitrogen in plants.
“I consider this a special honor,” said Dhugga, who leads CIMMYT’s research in biotechnology with a focus on editing genes for disease resistance in maize and wheat. He has published in high-impact scientific journals including Science, the Proceedings of the National Academy of Sciences (USA), Plant Cell, Molecular Plant, Plant Biotechnology Journal, Plant Physiology and others.
AAAS Fellows are elected each year by their peers serving on the Council of AAAS, the organization’s member-run governing body. Scientists who have received this recognition include the inventor Thomas Edison (1878), anthropologist Margaret Mead (1934), and popular science author Jared Diamond (2000), as well as numerous Nobel laureates. The election of Dhugga doubles the tally of AAAS fellows at CIMMYT, the other one being Ravi P. Singh, Distinguished Scientist and Head of Global Wheat Improvement.
“Kanwarpal merits CIMMYT’s wholehearted congratulations for this prestigious recognition of his standing in science,” said Kevin Pixley, director of CIMMYT’s Genetics Resources program, to which Dhugga belongs. “I’m humbled and grateful to count him as a member of our team.”
Dhugga identified the gene for an enzyme that propels the chemical reactions to produce guar gum, a cell wall polymer that is a dominant component of the edible kernel of the coconut. (Photo: Allen Wen/CIMMYT)
A native of Punjab in India, Dhugga has a M.Sc. in Plant Breeding from Punjab Agricultural University and a Ph.D. in Botany (Plant Genetics) from the University of California, Riverside. He was introduced to membrane protein biochemistry and cell wall synthesis during his postdoctoral research at Stanford University in the laboratory of Peter Ray. Prior to joining CIMMYT in 2015, Dhugga worked at DuPont Pioneer (now Corteva) from 1996 to 2014.
In addition to scientific excellence, Dhugga counts among his achievements prominent international, public-private partnerships, such as the one he led between DuPont Pioneer and the Australian Centre for Plant Functional Genomics to explore new avenues to improve plant nitrogen use efficiency and reduce culm (stalk) lodging in cereals from 2004 to 2014. He continues to explore opportunities to secure funds for undertaking joint work with the collaborators from that period, thanks to the relationships fostered then. One of the scientists in his current group actually completed his Ph.D. under that collaboration.
As part of science outreach he has guided the research of many graduate students in Australia, Canada, India, and the US, a country of which he is also a citizen, and helped make high-quality education accessible to the underprivileged, including establishing a private school in his ancestral village in the state of Punjab in India.
The 2019 Fellows will receive rosette pins in gold and blue, colors symbolizing science and engineering. (Photo: AAAS)
Dhugga has also been successful as a principal or co-principal investigator in attracting significant funding for scientific research from public agencies such as the US Department of Energy, the US National Science Foundation, USAID, and the Australian Research Council. Part of his current research is supported by a grant from the Bill & Melinda Gates Foundation. At DuPont Pioneer he was the recipient of two separate, highly competitive research grants to carry out high-risk, discovery research outside of the area of the assigned company goals.
Among his research endeavors, Dhugga highlights a breakthrough he made in the area of cell wall biosynthesis under a discovery research grant from DuPont Pioneer. He identified the gene for an enzyme that propels the chemical reactions to produce guar gum, a cell wall polymer that is also used in industrial products from shampoos to ice cream and is a dominant component of the coconut kernel. The results were published in Science. On a basic level, this provided biochemical evidence for the first time for the involvement of any of the genes from the large plant cellulose synthase gene family in the formation of a cell wall polymer. Dhugga also confides that whenever he flies over coconut plantations anywhere, he gets butterflies in his stomach at the thought that he was the first one to know how simple molecules made a complex matrix that became the edible kernel of the coconut.
“That study constituted a prime example of the power of cross-disciplinary research in answering a longstanding fundamental question in plant biology,” he said. “Assaying enzymes involved in the formation of cell wall polymers is extremely difficult. The approach we used — identify a candidate gene by combining genomics with biochemistry and then express it in a related species lacking the product of the resulting enzyme to demonstrate its function — was subsequently applied by other scientists to identify genes involved in the formation of other key plant cell wall polymers.”
Dhugga will receive a pin as a token of his election as Fellow in an AAAS ceremony in Seattle, Washington, USA, on February 15, 2020.
Akshaya Biswal is a scientist specialized in plant transformation and tissue culture, working with CIMMYT’s Genetic Resources Program. His current work focuses on application of gene editing to improve host-plant resistance.
CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats)/Cas9-mediated genome editing has revolutionized our ability to study gene function and alter it to improve biotic and abiotic stress tolerance, increase yield potential of crop plants or even to improve the quality of grains. Various plant diseases cause up to 30% yield loss in cereals. Polyploidy in maize and wheat poses additional difficulty to breeders for developing and deploying resistant lines to pathogens. Some these can be solved by biotechnological intervention with relative ease. Biswal’s team uses gene editing to: control Maize Lethal Necrosis (MLN) in Africa for improved grain harvests; improve stem rust and powdery mildew resistance in wheat; and discover and validate the function of candidate genes underpinning large effect QTLs.
Prior to joining CIMMYT, Biswal completed postdoctoral placements at the International Rice Research Institute (IRRI) and the University of North Carolina. He earned a PhD in Biotechnology at Jawaharlal Technological University, an MSc from Banaras Hindu University, and a BSc from Utkal University, India.
Participants of the EBS DevOps Hackathon stand for a group photo at CIMMYT’s global headquarters in Texcoco, Mexico. (Photo: Eleusis Llanderal Arango/CIMMYT)
From October 21 to November 1, 2019, software developers and administrators from several breeding software projects met at the global headquarters of the International Maize and Wheat Improvement Center (CIMMYT) in Mexico to work on delivering an integrated solution to crop breeders.
Efforts to improve crop breeding for lower- and middle-income countries involves delivering better varieties to farmers faster and for less cost. These efforts rely on a mastery of data and technology throughout the breeding process.
To realize this potential, the CGIAR Excellence in Breeding Platform (EiB) is developing an Enterprise Breeding System (EBS) as a single solution for breeders. EBS will integrate the disparate software projects developed by different institutions over the years. This will free breeders from the onerous task of managing their data through different apps and allow them to rapidly optimize their breeding schemes based on sound data and advanced analytics.
“None of us can do everything,” said Tom Hagen, CIMMYT-EiB breeding software product manager, “so what breeding programs are experiencing is in fact fragmented IT. How do we come together as IT experts to create a system through our collective efforts?”
For the EBS to succeed, it is essential that the system is both low-cost and easy to deploy. “The cost of the operating environment is absolutely key,” said Jens Riis-Jacobson, international systems and IT director at CIMMYT. “We are trying to serve developing country institutions that have very little hard currency to pay for breeding program operations.”
Stacked software
During the hackathon, twelve experts from software projects across CGIAR and public sector institutions used a technology called Docker to automatically stack the latest versions of their applications into a single configuration file. This file can be loaded into any operating environment in less than four minutes — whether it be a laptop, local server or in the cloud. Quickly loading the complete system into a cloud environment means EBS can eventually be available as a one-click, Software-as-a-Service solution. This means that institutions will not need sophisticated IT infrastructure or support staff to maintain the software.
Behind the scenes, different applications are replicated in a single software solution, the Enterprise Breeding System. (Photo: CIMMYT)
“If everything goes as planned, the end users won’t know that we exist,” said Peter Selby, coordinator of the Breeding API (BrAPI) project, an online collective working on a common language for breeding applications to communicate with each other. Updates to individual apps will be automatically loaded, tested and pushed out to users.
As well as the benefits to breeders, this automated deployment pipeline should also result in better software. “We have too little time for development because we spend too much time in deployment and testing,” said Riis-Jacobson.
A cross-institution DevOps culture
Though important technical obstacles were overcome, the cultural aspect was perhaps the most significant outcome of the hackathon. The participants found that they shared the same goals, language and were able to define the common operating environment for their apps to work together in.
“It’s really important to keep the collaboration open,” said Roy Petrie, DevOps engineer at the Genomic and Open-Source Breeding Informatics Initiative (GOBii) based at the Boyce Thompson Institute, Cornell University. “Having a communications platform was the first thing.”
In the future, this could mean that teams synchronize their development timeline to consistently release updates with new versions of the EBS, suggested Franjel Consolacion, systems admin at CIMMYT.
“They are the next generation,” remarked Hagen. “This is the first time that this has happened in CGIAR informatics and it validated a key aspect of our strategy: that we can work together to assemble parts of a system and then deploy it as needed to different institutions.”
By early 2020, selected CIMMYT and International Rice Research Institute (IRRI) breeding teams will have access to a “minimal viable implementation” of the EBS, in which they can conduct all basic breeding tasks through a simple user interface. More functionality, breeding programs and crops from other institutions including national agricultural research programs will be added in phases over three years.
Four scientists from the CIMMYT community have been included in the Highly Cited Researchers list for 2019, Published by the Web of Science Group, a Clarivate Analytics company.
The list identifies scientists and social scientists who have demonstrated significant influence through publication of multiple papers, highly cited by their peers, during the last decade. For the 2019 list, analysts surveyed papers published and cited during 2008-2018 which ranked in the top 1% by citations for their ESI field and year.
Researchers are selected for their exceptional research performance in one of 21 fields, or across several fields.
This year’s recipients affiliated with CIMMYT include:
José Crossa: Cross-field category. CIMMYT Distinguished Scientist at the Biometrics and Statistics Unit with the Genetic Resources Program.
Julio Huerta: Cross-field category. CIMMYT-seconded INIFAP wheat breeder and rust geneticist.
Ravi Prakash Singh: Agricultural Sciences category. CIMMYT Distinguished Scientist and Head of Bread Wheat Improvement.
It is a significant honor to be part of this list, as it indicates that their peers have consistently acknowledged the influence of their research contributions in their publications and citations.
“Congratulations and thanks to these colleagues for effectively communicating their excellent science, multiplying CIMMYT’s impact by influencing thousands of readers in the international research community,” said CIMMYT Genetic Resources Program Director Kevin Pixley.
The Frank N. Meyer Medal for Plant Genetic Resources. (Photo: Kevin Pixley/CIMMYT)
Thomas Payne, head of the Wheat Germplasm Bank at the International Maize and Wheat Improvement Center (CIMMYT), was awarded the Frank N. Meyer Medal for Plant Genetic Resources this morning at the annual meeting of the American Society of Agronomy, the Crop Science Society of America, and the Soil Science Society of America, held in San Antonio, Texas.
The Frank N. Meyer Medal recognizes contributions to plant germplasm collection and use, as well as dedication and service to humanity through the collection, evaluation or conservation of earth’s genetic resources. The award was presented by Clare Clarice Coyne, U.S. Department of Agriculture (USDA) research geneticist.
As an award recipient, Payne delivered a lecture that touched on the philosophy, history and culture surrounding plant genetic diversity and its collectors, and CIMMYT’s important role in conserving and sharing crop diversity.
The scientist has focused his career on wheat improvement and conservation. In addition to leading CIMMYT’s Wellhausen-Anderson Wheat Genetic Resources Collection, one of the world’s largest collection of wheat and maize germplasm, he manages the CIMMYT International Wheat Improvement Network. He is the current Chair of the Article 15 Group of CGIAR Genebank Managers, and has served as Secretary to the CIMMYT Board of Trustees. His association with CIMMYT began immediately after obtaining a PhD at the University of Nebraska–Lincoln in 1988, and he has held positions for CIMMYT in Ethiopia, Mexico, Syria, Turkey and Zimbabwe.
Thomas Payne delivers a presentation at the Crop Science Society of America’s annual Genetic Resources breakfast, where he received the award. (Photo: Kevin Pixley/CIMMYT)
“CIMMYT is the largest distributor of maize and wheat germplasm worldwide, with materials emanating from its research and breeding programs, as well as held in-trust in the germplasm bank. The Meyer Medal is a reflection of the impact CIMMYT makes in the international research community — and in farmers’ fields throughout the developing world,” Payne said.
Located at CIMMYT headquarters outside Mexico City, the CIMMYT Wheat Germplasm Bank contains nearly 150,000 collections of seed of wheat and related species from more than 100 countries. Collections preserve the diversity of unique native varieties and wild relatives of wheat and are held under long-term storage for the benefit of humanity, in accordance with the 2007 International Treaty on Plant Genetic Resources for Food and Agriculture. The collections are also studied and used as a source of diversity to breed for crucial traits such as heat and drought tolerance, resistance to crop diseases and pests, grain yield productivity, and grain quality. Seed is freely shared on request to researchers, students, and academic and development institutions worldwide.
In his remarks, Payne also highlighted the story of Frank N. Meyer, after whom the award is named. Meyer, an agricultural explorer for the USDA in the 1900s, spent a decade traveling under harsh conditions through China to collect new plant species suitable for production on the United States’s expanding farmland. Among more than 2,500 plants that he introduced to the U.S. — including varieties of soybeans, oats, wild pears, and asparagus — the Meyer lemon was named in his honor. As he pointed out, Meyer worked during a historical period of great scientific discoveries, including those by his contemporaries Marie Curie and the Wright brothers.
Among those attending the ceremony were Payne’s sister, Susan Payne, and CIMMYT colleagues Kevin Pixley, director of Genetic Resources; Denise Costich, head of the CIMMYT Maize Germplasm Bank; and Alexey Morgunov, head of the Turkey-based International Winter Wheat Improvement Program.
The head of CIMMYT’s Global Wheat Program Hans-Joachim Braun and CIMMYT scientist Alexey Morgunov are also receiving honors or awards this week at the annual meeting of the American Society of Agronomy, the Crop Science Society of America, and the Soil Science Society of America. The meeting convenes around 4,000 scientists, professionals, educators, and students to share knowledge and recognition of achievements in the field.
Thomas Payne (right) celebrates the award with his sister Susan Payne (center) and CIMMYT scientist Alexey Morgunov. (Photo: Kevin Pixley/CIMMYT)
Thomas Payne (left) stands for a photo with CIMMYT’s Director of Genetic Resources Kevin Pixley.
Thomas Payne (left) with Head of CIMMYT’s Maize Germplasm Bank Denise Costich. (Photo: Kevin Pixley/CIMMYT)
Visitors from the Embassy of Vietnam in Mexico and members of CIMMYT senior management stand for a group photograph next to the Norman Borlaug statue at CIMMYT’s global headquarters. (Photo: Jose Luis Olin Martinez for CIMMYT)
Vietnamese officials expressed interest in increased future cooperation with the International Maize and Wheat Improvement Center (CIMMYT). A delegation from the Embassy of Vietnam in Mexico visited CIMMYT’s global headquarters in Texcoco, Mexico, on October 21, 2019. The delegation was composed of Hien Do Tat, First Secretary of Technology Science, and translator Cuc Doan Thi Thu.
CIMMYT sends germplasm to Vietnam and has previously collaborated with the country through several projects. More than twenty Vietnamese scientists have received training from CIMMYT.
The Vietnamese delegation was particularly interested in CIMMYT’s work with drought-tolerant maize and requested expert help with fall armyworm, which has appeared in Vietnam for the first time earlier this year. They also expressed surprise at the range of CIMMYT activities, as they were under the impression that the organization’s sole purpose was plant breeding.
CIMMYT Director General Martin Kropff reinforced interest in further cooperation with Vietnam, emphasizing the importance of appropriate mechanization and sustainable intensification in agricultural development.
Vietnam produced 5.1 million tons of maize a year, grown on more than one million hectares, according to the latest available figures.
Partnerships and how to increase impact were two of the key issues discussed by the Board of Trustees of the International Maize and Wheat Improvement Center (CIMMYT) during their meeting in Kenya in October 6-10, 2019. Management and strategy discussions were combined with field trips and interactions with CIMMYT researchers and partners. Board members visited the research stations in Kiboko and Naivasha, as well as two partner seed companies in Machakos and Nairobi.
“To ensure CIMMYT’s crop breeding research benefits smallholder farmers, it is important for us to better understand how partnerships between CIMMYT and seed companies work on the ground, to know how seeds move from our research stations to the farmers,” said Marianne Bänziger, CIMMYT’s deputy director general for research and partnership.
CIMMYT board members and staff stand for a group photo outside the offices of East African Seed. (Photo: Jerome Bossuet/CIMMYT)
East African Seed, a family-owned seed business established in Nairobi in the 1970s, sells over 300 products, from maize and vegetable seeds to phytosanitary solutions. The company works through a large network of stockists and distributors across Burundi, the Democratic Republic of Congo, Kenya, Rwanda, South Sudan, Tanzania and Uganda.
Rogers Mugambi, chief business manager of East African Seed, underlined the successful partnership with CIMMYT, getting access to high-yielding disease-resistant germplasm and receiving technical support for the company’s breeding team. Mugambi highlighted CIMMYT’s contribution to contain the devastating maize lethal necrosis (MLN) outbreak since 2011. Most commercial varieties on the market fared badly against this new viral disease, but in 2020 East African Seed will launch two new MLN-tolerant varieties on the market thanks to CIMMYT’s breeding work.
Dryland Seed, another partner seed company, was established in 2005 in Kenya’s Machakos County. It commercializes the drought-tolerant SAWA maize hybrid, based on CIMMYT lines. Featured recently on Bill Gates’s blog, this hybrid is a success among farmers, thanks to earliness, nitrogen use efficiency and good yield potential in water-stressed regions. Dryland Seed’s production grew from 25 to 500 tons of seed per year, reaching out 42,000 farmers a year.
General view of the East African Seed warehouse. (Photo: Jerome Bossuet/CIMMYT)
Keeping seeds in business
When asked about the uniqueness of East African Seed, Mugambi highlighted trust and consistency in quality. They nurture their agrodealer network by investing in extension services and organizing evening meetings with stockists to discuss how to farm and be profitable. “Knowing and supporting the agrodealers selling your products is crucial, to make sure the stockists sell the right seeds and inputs, and store them well,” Mugambi explained.
Marianne Banziger (right), CIMMYT’s deputy director for research and partnership, listens to a Dryland Seed sales manager during a visit to a farm supplies shop in Machakos, Kenya. (Photo: Jerome Bossuet/CIMMYT)
“Many seed companies could learn from you. Quality control is crucial for any seed business as you sell genetics and any crop failure at farm level will jeopardize farmers’ trust in the company’ seeds,” said Bill Angus, CIMMYT Board member.
Ngila Kimotho, managing director of Dryland Seed, pointed out the financial challenges for a small local seed company to grow in this risky but important agribusiness. The company has to pay out-growers, sometimes face default payment by some agrodealers, while low-interest credit offers are scarce as “banks and microfinance institutions target short-term reliable businesses, not climate-risky rainfed farming,” Kimotho explained. Combining drought-tolerant crops with insurance products could lower business risks for banks.
Bringing top-notch research to farmers
“I am worried about the mutating stem rust which seems to break down the resistance of some popular wheat varieties,” stressed Joseph Nalang’u, a farmer in Narok with 600 acres dedicated to wheat and 100 to maize. “The unpredictable weather is another major concern. When I started farming, we knew exactly when the planting season would start, and this helped us in our planning. That is no longer the case.”
African farmers need agricultural research. A research that is responsive to develop rapidly scalable and affordable solutions against numerous emerging pests and diseases like wheat rusts, MLN or fall armyworm. They need advice on how to adapt to unpredictable climate.
While visiting the MLN Quarantine and Screening Facility in Naivasha, CIMMYT’s Board members discussed research priorities and delivery pathways with farmers, seed and input companies, and representatives of Kenya Agricultural and Livestock Research Organization (KALRO), Kenya Plant Health Inspectorate Service (KEPHIS) and the Ministry of Agriculture.
CIMMYT board members, staff, partners and farmers listen to a researcher at the MLN Screening Facility in Naivasha, Kenya. (Photo: Joshua Masinde/CIMMYT)
“When you visit Naivasha MLN research facility or Njoro wheat rust phenotyping platform, both co-managed by CIMMYT and KALRO, you see a partnership that works very well,” said Zachary Kinyua, the assistant director for crop health research at KALRO. “These facilities are open to public-private collaboration, they generate important public goods for farmers, large and small.”
“If we develop or co-develop wonderful technologies but they don’t reach the farmers, that would be a fun and wonderful experience but with no impact,” said Kevin Pixley, CIMMYT’s director of the Genetic Resources program. “We depend on partners in the national agricultural research systems, seed companies and other private and public partners to realize the desired impact.”
“It is always so inspiring to see on the ground the results of years of research, to hear some of our partners talking about the real impact this research makes. The multiplier effect of what we do never ceases to amaze me,” expressed Nicole Birell, chair of CIMMYT’s Board of Trustees.
Cover image: CIMMYT board members and staff visited Riziki Farm Supplies, one of the agrodealers in Machakos which sells SAWA hybrid maize. (Photo: Jerome Bossuet/CIMMYT)
Norman Borlaug was awarded the Nobel Peace Prize in 1970 in recognition of his contributions to world peace through increasing food production. In the latest episode of the BBC radio show Witness History, Rebecca Kesby interviews Ronnie Coffman, student and friend of Norman Borlaug.
Among other stories, Coffman recalls the moment when Borlaug was notified about the Nobel Prize — while working in the wheat fields in Mexico — and explores what motivated Borlaug to bring the Green Revolution to India.
Pioneering research on our three most important cereal grains — maize, rice, and wheat — has contributed enormously to global food security over the last half century, chiefly by boosting the yields of these crops and by making them more resilient in the face of drought, flood, pests and diseases. But with more than 800 million people still living in chronic hunger and many more suffering from inadequate diets, much remains to be done. The challenges are complicated by climate change, rampant degradation of the ecosystems that sustain food production, rapid population growth and unequal access to resources that are vital for improved livelihoods.
In recent years, a consensus has emerged among agricultural researchers and development experts around the need to transform global food systems, so they can provide healthy diets while drastically reducing negative environmental impacts. Certainly, this is a central aim of CGIAR — the world’s largest global agricultural research network — which views enhanced nutrition and sustainability as essential for achieving the Sustainable Development Goals. CGIAR scientists and their many partners contribute by developing technological and social innovations for the world’s key crop production systems, with a sharp focus on reducing hunger and poverty in low- and middle-income countries of Africa, Asia and Latin America.
The importance of transforming food systems is also the message of the influential EAT-Lancet Commission report, launched in early 2019. Based on the views of 37 leading experts from diverse research disciplines, the report defines specific actions to achieve a “planetary health diet,” which enhances human nutrition and keeps the resource use of food systems within planetary boundaries. While including all food groups — grains, roots and tubers, pulses, vegetables, fruits, tree nuts, meat, fish, and dairy products — this diet reflects important shifts in their consumption. The major cereals, for example, would supply about one-third of the required calories but with increased emphasis on whole grains to curb the negative health effects of cheap and abundant supplies of refined cereals.
This proportion of calories corresponds roughly to the proportion of its funding that CGIAR currently invests in the major cereals. These crops are already vital in diets, cultures, and economies across the developing world, and the way they are produced, processed and consumed must be a central focus of global efforts to transform food systems. There are four main reasons for this imperative.
Aneli Zárate Vásquez (left), in Mexico’s state of Oaxaca, sells maize tortillas for a living. (Photo: P. Lowe/CIMMYT)
1. Scale and economic importance
The sheer extent of major cereal production and its enormous value, especially for the poor, account in large part for the critical importance of these crops in global food systems. According to 2017 figures, maize is grown on 197 million hectares and rice on more than 167 million hectares, mainly in Asia and Africa. Wheat covers 218 million hectares, an area larger than France, Germany, Italy, Spain and the UK combined. The total annual harvest of these crops amounts to about 2.5 billion tons of grain.
Worldwide production had an estimated annual value averaging more than $500 billion in 2014-2016. The prices of the major cereals are especially important for poor consumers. In recent years, the rising cost of bread in North Africa and tortillas in Mexico, as well as the rice price crisis in Southeast Asia, imposed great hardship on urban populations in particular, triggering major demonstrations and social unrest. To avoid such troubles by reducing dependence on cereal imports, many countries in Africa, Asia and Latin America have made staple crop self-sufficiency a central element of national agriculture policy.
Women make roti, an unleavened flatbread made with wheat flour and eaten as a staple food, at their home in the Dinajpur district, Bangladesh. (Photo: S. Mojumder/Drik/CIMMYT)
2. Critical role in human diets
Cereals have a significant role to play in food system transformation because of their vital importance in human diets. In developing countries, maize, rice, and wheat together provide 48% of the total calories and 42% of the total protein. In every developing region except Latin America, cereals provide people with more protein than meat, fish, milk and eggs combined, making them an important protein source for over half the world’s population.
Yellow maize, a key source of livestock feed, also contributes indirectly to more protein-rich diets, as does animal fodder derived from cereal crop residues. As consumption of meat, fish and dairy products continues to expand in the developing world, demand for cereals for food and feed must rise, increasing the pressure to optimize cereal production.
In addition to supplying starch and protein, the cereals serve as a rich source of dietary fiber and nutrients. CGIAR research has documented the important contribution of wheat to healthy diets, linking the crop to reduced risk of type 2 diabetes, cardiovascular disease, and colorectal cancer. The nutritional value of brown rice compared to white rice is also well known. Moreover, the recent discovery of certain genetic traits in milled rice has created the opportunity to breed varieties that show a low glycemic index without compromising grain quality.
Golden Rice grain (left) compared to white rice grain. Golden Rice is unique because it contains beta carotene, giving it a golden color. (Photo: IRRI)
The major cereals have undergone further improvement in nutritional quality during recent years through a crop breeding approach called “biofortification,” which boosts the content of essential vitamins or micronutrients. Dietary deficiencies of this kind harm children’s physical and cognitive development, and leave them more vulnerable to disease. Sometimes called “hidden hunger,” this condition is believed to cause about one-third of the 3.1 million annual child deaths attributed to malnutrition. Diverse diets are the preferred remedy, but the world’s poorest consumers often cannot afford more nutritious foods. The problem is especially acute for women and adolescent girls, who have unequal access to food, healthcare and resources.
It will take many years of focused effort before diverse diets become a reality in the lives of the people who need them most. Diversified farming systems such as rice-fish rotations that improve nutritional value, livelihoods and resilience are a step in that direction. In the meantime, “biofortified” cereal and other crop varieties developed by CGIAR help address hidden hunger by providing higher levels of zinc, iron and provitamin A carotenoids as well as better protein quality. Farmers in many developing countries are already growing these varieties.
A 2018 study in India found that young children who ate zinc-biofortified wheat in flatbread or porridge became ill less frequently. Other studies have shown that consumption of provitamin A maize improves the body’s total stores of this vitamin as effectively as vitamin supplementation. Biofortified crop varieties are not a substitute for food fortification (adding micronutrients and vitamins during industrial food processing). But these varieties can offer an immediate solution to hidden hunger for the many subsistence farmers and other rural consumers who depend on locally produced foods and lack access to fortified products.
Ruth Andrea (left) and Maliamu Joni harvest cobs of drought-tolerant maize in Idakumbi, Mbeya, Tanzania. (Photo: Peter Lowe/CIMMYT)
4. Wide scope for more sustainable production
Cereal crops show much potential not only for enhancing human heath but that of the environment as well. Compared to other crops, the production of cereals has relatively low environmental impact, as noted in the EAT-Lancet report. Still, it is both necessary and feasible to further enhance the sustainability of cereal cropping systems. Many new practices have a proven ability to conserve water as well as soil and land, and to use purchased inputs (pesticides and fertilizers) far more efficiently. With innovations already available, the amount of water used in current rice cultivation techniques, for example, can be significantly reduced from its present high level.
Irrigation scheduling, laser land leveling, drip irrigation, conservation tillage, precision nitrogen fertilization, and cereal varieties tolerant to drought, flooding and heat are among the most promising options. In northwest India, scientists recently determined that optimal practices can reduce water use by 40%, while maintaining yields in rice-wheat rotations. There and in many other places, the adoption of new practices to improve cereal production in the wet season not only leads to more efficient resource use but also creates opportunities to diversify crop production in the dry season. Improvements to increase cereal crop yields also reduces their environmental footprint; using less land, enhancing carbon sequestration and biodiversity and, for rice, reducing methane emissions per kilo of rice produced. Given the enormous extent of cereals cultivation, any improvement in resource use efficiency will have major impact, while also freeing up vast amounts of land for other crops or natural vegetation.
A major challenge now is to improve access to the knowledge and inputs that will enable millions of farmers to adopt new techniques, making it possible both to diversify production and grow more with less. Another key requirement consists of clear signals from policymakers, especially where land and water are limited, about the priority use of these resources — for example, irrigating low-value cereals to bolster food security versus applying the water to higher value crops and importing staple cereals.
Morning dew on a wheat spike. (Photo: Vadim Ganeyev/CIMMYT)
Toward a sustainable dietary revolution
Future-proofing the global food system requires bold steps. Policy and research need to support a double transformation, centered on nutrition and sustainability.
CGIAR works toward nutritional transformation of our food system through numerous global partnerships. We give high priority to improving cereal crop systems and food products, because of their crucial importance for a growing world population. Recognizing that this alone will not suffice for healthy diets, we also strongly promote greater dietary diversity through our research on various staple crops and production systems and by raising public awareness of more balanced and nutritious diets.
To help achieve a sustainability transformation, CGIAR researchers and partners have developed a wide array of techniques that use resources more efficiently, enhance the resilience of food production in the face of climate change and reduce greenhouse gas emissions, while achieving sustainable increases in crop yields. At the same time, we are generating new evidence on which techniques work best under what conditions to target the implementation of these solutions more effectively.
The ultimate impact of our work depends crucially on the growing resolve of developing countries to promote better diets and more sustainable food production through strong policies and programs. CGIAR is well prepared to help strengthen these measures through research for development, and we are confident that our work on cereals, with continued donor support, will have high relevance, generating a wealth of innovations that help drive the transformation of global food systems.
Martin Kropff is the Director General of the International Maize and Wheat Improvement Center (CIMMYT).
Matthew Morell is the Director General of the International Rice Research Institute (IRRI).
As the calendar turns to October 16, it is time to celebrate World Food Day. At the International Maize and Wheat Improvement Center (CIMMYT), we are bringing you a few facts you should know about maize and wheat, two of the world’s most important crops.
According to 2017 figures, maize is grown on 197 million hectares. Wheat covers 218 million hectares, an area larger than France, Germany, Italy, Spain and the UK combined. The total annual harvest of these two crops amounts to about 1.9 billion tons of grain.
A little girl eats a freshly-made roti while the women of her family prepare more, at her home in the village of Chapor, in the district of Dinajpur, Bangladesh. (Photo: S. Mojumder/Drik/CIMMYT)
2. Of the 300,000 known edible plant species, only 3 account for around 60% of our calories and proteins: maize, wheat and rice.
Farmers Kanchimaya Pakhrin and her neighbor Phulmaya Lobshan weed rice seedling bed sown by machine in Purnabas, Kanchanpur, Nepal. (Photo: P. Lowe/CIMMYT)
3. CIMMYT manages humankind’s most diverse maize and wheat collections.
The organization’s germplasm bank, also known as a seed bank, is at the center of its crop-breeding research. This remarkable, living catalog of genetic diversity is comprised of over 28,000 unique seed collections of maize and 150,000 of wheat.
From its breeding programs, CIMMYT sends half a million seed packages to 800 partners in 100 countries each year. With researchers and farmers, the center also develops and promotes more productive and precise maize and wheat farming methods and tools that save money and resources such as soil, water, and fertilizer.
Shelves filled with maize seed samples make up the maize active collection in the Wellhausen-Anderson Plant Genetic Resources Center at CIMMYT’s global headquarters in Texcoco, Mexico. Disaster-proof features of the bank include thick concrete walls and back-up power systems. (Photo: Xochiquetzal Fonseca/CIMMYT)
4. Maize and wheat are critical to a global food system makeover.
High-yield and climate-resilient maize and wheat varieties, together with a more efficient use of resources, are a key component of the sustainable intensification of food production needed to transform the global food system.
Miguel Ku Balam (left), from Mexico’s Quintana Roo state, cultivates the traditional Mesoamerican milpa system. “My family name Ku Balam means ‘Jaguar God’. I come from the Mayan culture,” he explains. “We the Mayans cultivate the milpa for subsistence. We don’t do it as a business, but rather as part of our culture — something we inherited from our parents.” (Photo: Peter Lowe/CIMMYT)
5. We must increase maize and wheat yields to keep feeding the world.
By the year 2050, there will be some 9.7 billion people living on Earth. To meet the growing demand from an increasing population and changing diets, maize yields must go up at least 18% and wheat yields 15% by 2030, despite hotter climates and more erratic precipitation.
Farmers walk through a wheat field in Lemo district, Ethiopia. (Photo: P. Lowe/CIMMYT)
6. Climate-smart farming allows higher yields with fewer greenhouse gas emissions.
Decades of research and application by scientists, extension workers, machinery specialists, and farmers have perfected practices that conserve soil and water resources, improve yields under hotter and dryer conditions, and reduce the greenhouse gas emissions and pollution associated with maize and wheat farming in Africa, Asia, and Latin America.
Kumbirai Chimbadzwa (left) and Lilian Chimbadzwa stand on their field growing green manure cover crops. (Photo: Shiela Chikulo/CIMMYT)
7. Wholegrain wheat is good for your health.
An exhaustive review of research on cereal grains and health has shown that eating whole grains, such as whole-wheat bread and other exceptional sources of dietary fiber, is beneficial for human health and associated with a reduced risk of cancer and other non-communicable diseases.
According to this study, consumption of whole grains is associated with a lower risk of coronary disease, diabetes, hypertension, obesity and overall mortality. Eating whole and refined grains is beneficial for brain health and associated with reduced risk for diverse types of cancer. Evidence also shows that, for the general population, gluten- or wheat-free diets are not inherently healthier and may actually put individuals at risk of dietary deficiencies.
8. Biofortified maize and wheat are combating “hidden hunger.”
“Hidden hunger” is a lack of vitamins and minerals. More than 2 billion people worldwide are too poor to afford diverse diets and cannot obtain enough critical nutrients from their staple foods.
To help address this, CIMMYT — along with HarvestPlus and partners in 18 countries — is promoting more than 60 maize and wheat varieties whose grain contains more of the essential micronutrients zinc and provitamin A. These biofortified varieties are essential in the fight against “hidden hunger.”
A 2015 study published in The Journal of Nutrition found that vitamin A-biofortified orange maize significantly improves visual functions in children, like night vision. (Photo: Libby Edwards/HarvestPlus)
9. 53 million people are benefiting from drought-tolerant maize.
Drought-tolerant maize developed by CIMMYT and partners using conventional breeding provides at least 25% more grain than conventional varieties in dry conditions in sub-Saharan Africa — this represents as much as 1 ton per hectare more grain on average.
These varieties are now grown on nearly 2.5 million hectares, benefiting an estimated 6 million households or 53 million people.
One study shows that drought-tolerant maize varieties can provide farming families in Zimbabwe an extra 9 months of food at no additional cost.
10. Quality protein maize is helping reduce child malnutrition.
Guillermo Garcia Barrios, a co-author of the study and student at Colegio de Postgraduados in Montecillo, Mexico, with a PHERAstar machine used to validate genetic markers. (Photo: Marcia MacNeil/CIMMYT)
To meet the demand for wheat from a rising and quickly urbanizing population, wheat yields in farmers’ fields must increase by an estimated 1.5% each year through 2030.
Of all the factors that influence yield, grain weight is the trait that is most stable and heritable for use in breeding improved wheat varieties. Breeders measure this by thousand grain weight (TGW).
Over the years, molecular scientists have made efforts to identify genes related to increased TGW, in order to speed up breeding through marker-assisted selection (MAS). Using MAS, breeders can select parents that contain genes related to the traits they are looking for, increasing the likelihood they will be passed on and incorporated in a new variety.
There have been some limited successes in these efforts: in the past years, a few genes related to increased TGW have been cloned, and a set of genetic markers have been determined to be used for MAS. However, the effects of most of these candidate genes have not yet been validated in diverse sets of wheat germplasm throughout the world that represent the full range of global wheat growing environments.
A group of wheat geneticists and molecular breeders from the International Maize and Wheat Improvement Center (CIMMYT) has recently conducted a thorough study to confirm the effects of the favorable alleles reported for these genes on TGW in CIMMYT wheat, and to identify new genetic determinants of this desired trait.
They found some good news and some bad news.
First, the good news: focusing on more than 4,000 lines of CIMMYT wheat germplasm they found 15 haplotype blocks significantly associated with TGW. Four haplotype blocks associated with TGW were also associated with grain yield — a grand prize for breeders, because in general the positive association of grain yield with TGW is less profound and sometimes even negative. However, of the 14 genes that had been previously reported to increase TGW, only one in CIMMYT’s 2015-2016 Elite Yield Trial and two in Wheat Associative Mapping Initiative panel were shown to have significant TGW associations.
Wheat grains prepared for placement in a Thousand Grain Weight machine. (Photo: Marcia MacNeil/CIMMYT)
The scientists also found that the alleles — pairs of genes on a chromosome that determine heredity — that were supposedly favorable to TGW actually decreased it. These candidate genes also appear to vary in their TGW effects with genetic background and/or environment.
Thus, these findings also provide a foundation for more detailed investigations, opening the door for more studies on the genetic background dependence and environment sensitivity of the known candidate genes for TGW.
“Our findings indicate that it will be challenging to use MAS based on these existing markers across individual breeding programs,” said Deepmala Sehgal, CIMMYT wheat geneticist and the primary author of the study.
However, efforts to identify new genetic determinants of TGW were promising. The authors’ study of CIMMYT germplasm found one locus on chromosome 6A that showed increases of up to 2.60 grams in TGW and up to 258 kilograms per hectare in grain yield.
Thousand Grain Weight is measured in this machine at CIMMYT’s global headquarters in Texcoco, Mexico. (Photo: Marcia MacNeil/CIMMYT)
This discovery expands opportunities for developing diagnostic markers to assist in multi-gene pyramiding — a process that can derive new and complementary allele combinations for enhanced wheat TGW and grain yield.
Most of all, the study highlights the strong need for better and more validation of the genes related to this and other traits, so that breeders can be sure they are using material that is confirmed to increase wheat grain weight and genetic yield.
“Our findings are very promising for future efforts to efficiently develop more productive wheat in both grain weight and grain yield,” said Sehgal. “This ultimately means more bread on household tables throughout the world.”
“Validation of Candidate Gene-Based Markers and Identification of Novel Loci for Thousand-Grain Weight in Spring Bread Wheat” in Frontiers in Plant Science by Deepmala Sehgal, Suchismita Mondal, Carlos Guzman, Guillermo Garcia Barrios, Carolina Franco, Ravi Singh and Susanne Dreisigacker was supported by funding from the CGIAR Research Program on Wheat (WHEAT), the Delivering Genetic Gain in Wheat (DGGW) project funded by the Bill & Melinda Gates Foundation and the UK Department for International Development (DFID), and the US Agency for International Development (USAID) Feed the Future Innovation Lab for Applied Wheat Genomics.
Mexican and international researchers have joined with farmers and specialists from Jala, a scenic valley near the Pacific Coast of Mexico’s state of Nayarit, in a critical strategy to save and study an endangered, legendary maize race whose ears once grew longer than a man’s forearm.
Specialists from the International Maize and Wheat Improvement Center (CIMMYT) are analyzing the race’s genetic diversity, in hopes of preserving its qualities and, in concert with Jala farmers, safeguarding its future and merits.
Efforts include a new maize festival that reprises a yearly contest begun in 1981 to honor the community’s largest maize ear, but the outsize Jala maize race faces myriad hurdles to survive, according to Carolina Camacho, CIMMYT socioeconomics researcher and festival collaborator.
“The Jala maize landrace is unsuited to mechanization due to its size and agronomic requirements,” said Camacho. “It must be sown by hand and, because the plant can grow to several meters or taller, the ears must be harvested on horseback.”
Jala maize is also losing out to more competitive and profitable improved varieties, Camacho added. It is prized locally for its floury texture, but many farmers favor varieties more suited to milling and which yield more husks — in high demand as tamale wraps — as well as fodder and feed. The floury texture also means the grain is less dense and so fetches a lower price on external markets, where grain is sold by weight.
Youth panel discussion at the Feria de la Mazorca del Maize Nativo with Carolina Camacho, CIMMYT (third from right). (Photo: Denise Costich/CIMMYT)
A fair fight for preservation
The most recent “Feria de la Mazorca del Maíz Nativo,” or Landrace Maize Ear Festival, was held in December 2018. Under the boughs of a giant guanacaste tree in the town square of Coapan, Jala Valley, children, elders, cooks and dancers celebrated maize and its associated traditions. The festival culminated in the contest for the largest maize ear, with the winning farmer’s submission measuring nearly 38 centimeters in length.
The competition typically takes place in August as part of Jala’s two-week “Feria del Elote,” or green ear festival, first established to foster the appreciation and preservation of the native maize.
CIMMYT scientists helped the community set up a local genebank to store Jala landrace seed, according to Denise Costich, head of the CIMMYT maize germplasm bank and festival collaborator.
“This enhances the community’s role as custodians of landrace diversity and their access to the seed,” said Costich, adding that Jala seed from as far back as the early 1980s forms part of CIMMYT’s maize collections, which comprise 28,000 unique samples.
Under CIMMYT’s Seeds of Discovery project, scientists are analyzing the remaining genetic potential in the Jala maize population, particularly to understand the extent and effects of both inbreeding and outcrossing.
On the one hand, Costich said, Jala’s unique genetic pedigree appears to be diluted from mixing with other varieties in the valley whose pollen lands on Jala silks. At the same time, she worries about possible inbreeding in some small and isolated valley pockets where Jala is grown.
Finally, the yearly contest, for which maize ears are harvested in the green stage before maturity, precludes use of the grain as seed and so may also remove inheritable potential for large ears from the local maize gene pool.
Farewell to small-scale farmers?
Setting up the contest entries in Coapan: (l-r) Cristian Zavala of the CIMMYT maize genebank recording data; Rafael Mier from Fundacion Tortillas de Maiz Mexicana; Victor Vidal, INIFAP collaborator and judge of the contest; and Alfredo Segundo of the CIMMYT maize genebank. (Photo: Denise Costich/CIMMYT)
Whatever the causes, Jala maize isn’t what it used to be. In 1924, a visiting scientist observed maize plants over 6 meters in height and with ears more than 60 centimeters long — far longer than today’s samples.
One grave challenge to the landrace’s continued existence is the steady disappearance of older farmers who grow it. As throughout rural Mexico, many youths are leaving farm communities like Jala in search of better opportunities and livelihoods in cities.
Camacho believes the festival and contest encourage farmers to continue growing Jala maize but cannot alone ensure the landrace’s preservation.
“The solutions need to encompass all aspects of Jala maize and be supported by the entire community, particularly young people,” said Camacho.
The festival in Coapan included a panel discussion with local youths, among them graduate students from the Autonomous University of Nayarit.
“The panelists highlighted the lack of opportunities in rural areas and the need for an economically secure future; things that Jala maize doesn’t offer,” Camacho said.
The festival is a collaboration among Costich, Camacho, Victor Vidal of INIFAP-Nayarit, and local partners including Gilberto González, Ricardo Cambero, Alondra Maldonado, Ismael Elías, Renato Olmedo (CIMMYT), and Miguel González Lomelí.
Blast appears sporadically on wheat and grows well on numerous other plants and crops, so rotations do not control it. The irregular frequency of outbreaks also makes it hard to understand or predict the precise conditions for disease development, or to methodically select resistant wheat lines.
The Magnaporthe oryzae fungus is physiologically and genetically complex, so even after more than three decades, scientists do not fully understand how it interacts with wheat or which genes in wheat confer durable resistance.
Four scientists from the CIMMYT community have been included in the 
