A number of scientists from the International Maize and Wheat Improvement Center (CIMMYT) presented this week at the International Plant and Animal Genome Conference (PAG) in San Diego, USA.
PAG is the largest agricultural genomics meeting in the
world, bringing together over 3,000 leading genetic scientists and researchers
from around the world to present their research and share the latest
developments in plant and animal genome projects. It provides an important
opportunity for CIMMYT scientists to highlight their work translating the
latest molecular research developments
into wheat and maize breeding solutions for better varieties.
Wheat Scientist Philomin Julianashared her findings on successfully identifying significant new chromosomal regions for wheat yield and disease resistance using the full wheat genome map. Juliana and her colleagues have created a freely-available collection of genetic information and markers for more than 40,000 wheat lines which will accelerate efforts to breed superior wheat varieties. She also discussed the value of genomic and high-throughput phenotyping tools for current breeding strategies adopted by CIMMYT to develop climate resilient wheat.
Principal Scientist Sarah Hearne discussed the smarter exploration of germplasm banks for breeding. Genebanks are reserves of native plant variation representing the evolutionary history of the crops we eat. They are a vital source of genetic information, which can accelerate the development of better, more resilient crops. However, it is not easy for breeders and scientists to identify or access the genetic information they need. Using the whole genebank genotypic data, long-term climate data from the origins of the genebank seeds and novel analysis methods, Hearne and her colleagues were able to identify elite genetic breeding material for improved, climate resilient maize varieties. They are now extending this approach to test the value of these data to improve breeding programs and accelerate the development of improved crops.
Distinguished Scientist Jose Crossa discussed the latest models and methods for combining
phenomic and genomic information to accelerate the development of
climate-resilient crop varieties. He highlighted the use of the Artificial
Neural Network — a model inspired by the human brain — to model the
relationship between input signals and output signals in crops. He also
discussed a phenotypic and genomic selection index which can improve response
to selection and expected genetic gains for all of an individual plant’s
genetic traits simultaneously.
Genomic Breeder Umesh Rosyara demonstrated the Genomic selection pipeline and other tools at a workshop on the genomic data management and marker application tool Galaxy. The software, developed by the Excellence in Breeding (EiB) platform, integrates a suite of bioinformatics analysis tools, R-packages – a free software environment for statistical computing and graphics – and visualization tools to manage routine genomic selection (GS) and genome wide association studies (GWAS) analysis. This allows crop breeders and genomic scientists without a programming background to conduct these analyses and create crop-specific workflows.
“PAG is currently the main international meeting touching
both crop and livestock genomics, so it’s an invaluable chance to connect and
share insights with research and breeding colleagues around the world,” said
“It’s also an important forum to highlight how we are
linking upstream and field, and help others do the same.”
This article was originally posted on the CGIAR website.
When the rice harvest season arrives in northwest India, farmers have only ten to twenty days to prepare their fields for the next season’s crop, wheat. For several decades now, this has meant using the fastest, cheapest tool at their disposal – fire – with devastating effects for human and environmental health.
In recent years, burning rice crop residue to clear land for wheat has reached crisis proportions. In November 2016, haze from agricultural burning in India’s northwestern states compounded New Delhi’s pollution problem, making the city’s air quality the worst in the world, and prompting a national emergency.
Innovations in farm machinery now hope to provide a more sustainable solution.
Where typical combine harvester machines leave behind narrow piles of dry residue that need to be cleared before planting can begin, innovative new machines and attachments can chop the leftover rice stalks, spread the residue evenly as mulch, and plant seeds into the soil – all without the need for clearing.
The simple adjustment in technique has the potential to bring transformational benefits for farmers, city-dwellers, and the environment.
“Rice residue burning is responsible for 40 percent of the air pollution in Delhi during the winter months, posing health hazards for several million people, adversely affecting soil health and creating the need for more water for crop production,” says M.L. Jat, a principal scientist at the International Maize and Wheat Improvement Center (CIMMYT), who leads the Center’s contributions to climate-smart villages in South Asia as part of the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS).
“Direct seeding of crops using the Happy Seeder helps reduce air pollution, improve soil health, and helps farmers adapt to weather risks, reducing greenhouse gas emissions, saving water and improving their income by US$ 100-150 per hectare per year.”
The approach has been tested and validated through a large number of trials over several years by the partnership as part of their research into climate-smart agriculture, with positive results. It has since been adopted by farmers over nearly 0.7 million hectares in northwest India. Efforts are now looking into even larger-scale adoption of the technology to cut out burning for good.
A burning question
Until recently, up to 84 percent of agricultural burning in India has happened in rotational rice-wheat fields, with farmers seeing it as the cheapest option for clearing between crops. But this ‘low-cost’ option bears many costs later down the track, including for farmers.
Burning is a major cause of air pollution, which poses serious public health risks, particularly for children and the elderly. Smoke from burning can stunt lung development in children, trigger chronic illnesses like asthma, and even cause cancer. India now has the highest rate of death from respiratory disease, at 159 deaths per 100,000 people.
Soil health is also affected by burning. Clearing by fire depletes carbon stocks and nutrients in soil. It also dries the land and contributes to heat stress, which slows crop growth. The result is lower yields and a greater need for irrigation, among other costs for farmers.
Over the long term, burning is also contributing to global climate change, and posing a setback for India’s targets to reduce greenhouse gas emissions.
Burning one ton of rice residue can release up to 13 kilograms of particulate matter into the atmosphere. At the height of burning, up to 30 million tons of rice residue was being cleared by fire in India’s northwestern states every year.
“Burning crop residues, and especially rice, contributes significantly to India’s annual emissions of greenhouse gases like methane, carbon dioxide, carbon mono-oxide, nitrous oxide, sulpher dioxide and so on,” Jat says.
“Using the Happy Seeder instead of burning can reduce greenhouse gas emissions by up to 79 percent.”
States like Haryana and Punjab are now taking action to stop burning, placing strict bans on the practice. But what are the alternatives for farmers, and how realistic are they?
Research shows that in their rush to remove rice residue from the field, farmers could be missing out on the use of a valuable resource.
When collected, leftover rice stalks can be reused as animal feed, and research is ongoing into its potential as a source of biofuel. But even if farmers can’t afford to clear, collect and process the residue, there are yet more benefits to be had by simply leaving it on their fields.
Chopped rice residue can be used as mulch, preparing the soil for the next season’s wheat crop. Using mulch can help farmers better control weeds, prevent waterlogging, lock in important nutrients, and maintain soil moisture, reducing the need for at least one round of irrigation per year. There is also evidence to suggest that mulch assists in carbon sequestration, bringing benefits for efforts on climate change.
The Happy Seeder planter is able to at once chop rice straw, bore through the residue to open a slit, deposit wheat seed and cover the seed. A combine harvester equipped with the Super Straw Management System (Super SMS) attachment can then be used to spread the residue evenly as mulch.
The technology eliminates the need for plowing, giving farmers the option of planting and harvesting their wheat crops up to two weeks earlier, avoiding the pre-monsoon heat. Importantly, it also eliminates the need to clear residue, effectively removing the need for burning.
The latest version of the improved Happy Seeder costs $1,900, which is still beyond the means of many farmers. But the machines are available for hire, and the number of service providers are rapidly growing.
In the northwestern states of Punjab and Haryana adoption of the machines has grown rapidly from 400 in use in 2015 to nearly 11,000 in 2018. In two years, the number of Happy Seeders in use in northwestern India is expected to grow to 35,000, bringing the practice of zero-tillage farming to around 2 million hectares of farmland.
As for the Super SMS attachment, there are now at least 100 manufacturers producing the essential piece, which is used on more than 5,000 combine harvesters. The attachment has been made mandatory for harvesters in Punjab and Haryana states, and is expected to be universally adopted over the next two years.
By avoiding burning, assisting sequestration and keeping carbon stocks in the soil for longer, the new approach to rice-wheat rotations is a win for climate-smart agriculture – a priority for the Government of India. As India’s population continues to grow and global weather patterns change, climate-smart farming will be essential for meeting national targets on emissions reduction and food security.
Ethiopia has huge potential and a suitable agroecology for growing wheat. However, its agriculture sector, dominated by a traditional farming system, is unable to meet the rising demand for wheat from increasing population and urbanization. Wheat consumption in Ethiopia has grown to 6.7 million tons per year, but the country only produces about 5 million tons per year on 1.7 million hectares. As a result, the country pays a huge import bill reaching up to $700 million per year to match supply with demand.
A new initiative is aiming to change this scenario, making Ethiopia wheat self-sufficient by opening new regions to wheat production.
“We have always been traditionally a wheat growing country, but focusing only in the highlands with heavy dependence on rain. Now that is changing and the government of Ethiopia has set a new direction for import substitution by growing wheat in the lowlands through an irrigated production system,” explained Mandefro Nigussie, director general of the Ethiopian Institute of Agricultural Research (EIAR). Nigussie explained that several areas are being considered for this initiative: Awash, in the Oromia and Afar regions; Wabeshebelle, in the Somali Region; and Omo, in the Southern Nations, Nationalities and Peoples Region (SNNPR).
A delegation from the International Maize and Wheat Improvement Center (CIMMYT) recently met Ethiopian researchers and policymakers to discuss CIMMYT’s role in this effort. Ethiopia’s new Minister of Agriculture and Natural Resources, Umar Hussein, attended the meeting.
“We understand that the government of Ethiopia has set an ambitious project but is serious about it, so CIMMYT is ready to support you,” said Hans Braun, director of the Global Wheat Program at CIMMYT.
CIMMYT and the Ethiopian government have identified priority areas that will support the new government initiative. These include testing a large number of advanced lines to identify the right variety for the lowlands; developing disease resistant varieties and multiplying good quality and large quantity early generation initial seed; refining appropriate agronomic practices that improve crop, land and water productivity; organizing exposure visits for farmers and entrepreneurs; implementing training of trainers and researchers; and technical backstopping.
CIMMYT has been providing technical support and resources for wheat and maize production in Ethiopia for decades. As part of this support, CIMMYT has developed lines that are resistant to diseases like stem and yellow rust, stress tolerant and suitable for different wheat agroecologies.
“This year, for example, CIMMYT has developed three lines which are suitable for the lowlands and proposed to be released,” said Bekele Abeyo, wheat breeder and CIMMYT Country Representative for Ethiopia. “In India, the green revolution wouldn’t have happened without the support of CIMMYT and we would also like to see that happen in Ethiopia.”
“With our experience, knowledge and acquired skills, there is much to offer from the CIMMYT side,” Abeyo expressed. He noted that mechanization is one of the areas in which CIMMYT excels. Through a business service providers model, CIMMYT and its partners tested the multipurpose two-wheel tractors in Oromia, Amhara, Tigray and the southern regions. Good evidence for impact was generated particularly in Oromia and the south, where service providers generated income and ensured food security.
“Import versus export depends on a comparative advantage and for Ethiopia it is a total disadvantage to import wheat while having the potential [to grow more],” said Hussein. “The Ministry of Agriculture is thus figuring out what it can do together with partners like CIMMYT on comparative advantages.”
Hussein explained that the private sector has always been on the sidelines when it comes to agriculture. With the new initiative, however, it will be involved, particularly in the lowlands where there is abundant land for development under irrigation and available water resources, with enormous investment potential for the private sector. This, he noted, is a huge shift for the agricultural sector, which was mainly taken care of by the government and smallholder farmers, with support from development partners.
Thinking beyond the local market
As it stands now, Ethiopia is the third largest wheat producing country in Africa and has great market potential for the region. With more production anticipated under the new initiative, Ethiopia plans to expand its market to the world.
“We want our partners to understand that our thinking and plan is not only to support the country but also to contribute to the global effort of food security,” Hussein explained. However, “with the current farming system this is totally impossible,” he added. Mechanization is one of the key drivers to increase labor, land and crop productivity by saving time and ensuring quality. The government is putting forward some incentives for easy import of machinery. “However, it requires support in terms of technical expertise and knowledge transfer,” Hussein concluded.
Researchers present highlights from 40 years of collaboration on wheat genomics, breeding for disease resistance and quality improvement.
This article by Emma Orchardson was originally posted on the CIMMYT website.
Global wheat production is currently facing great challenges, from increasing climate variation to occurrence of various pests and diseases. These factors continue to limit wheat production in a number of countries, including China, where in 2018 unseasonably cold temperatures resulted in yield reduction of more than 10% in major wheat growing regions. Around the same time, Fusarium head blight spread from the Yangtze region to the Yellow and Huai Valleys, and northern China experienced a shortage of irrigated water.
In light of these ongoing challenges, international collaboration, as well as the development of new technologies and their integration with existing ones, has a key role to play in supporting sustainable wheat improvement, especially in developing countries. The International Maize and Wheat Improvement Center (CIMMYT) has been collaborating with China on wheat improvement for over 40 years, driving significant progress in a number of areas.
Notably, a standardized protocol for testing Chinese noodle quality has been established, as has a methodology for breeding adult-plant resistance to yellow rust, leaf rust and powdery mildew. More than 330 cultivars derived from CIMMYT germplasm have been released in the country and are currently grown over 9% of the Chinese wheat production area, while physiological approaches have been used to characterize yield potential and develop high-efficiency phenotyping platforms. The development of climate-resilient cultivars using new technology will be a priority area for future collaboration.
In a special issue of Frontiers of Agricultural Science and Engineering focused on wheat genetics and breeding, CIMMYT researchers present highlights from global progress in wheat genomics, breeding for disease resistance, as well as quality improvement, in a collection of nine review articles and one research article. They emphasize the significance of using new technology for genotyping and phenotyping when developing new cultivars, as well as the importance of global collaboration in responding to ongoing challenges.
In a paper on wheat stem rust, CIMMYT scientists Sridhar Bhavani, David Hodson, Julio Huerta-Espino, Mandeep Randawa and Ravi Singh discuss progress in breeding for resistance to Ug99 and other races of stem rust fungus, complex virulence combinations of which continue to pose a significant threat to global wheat production. The authors detail how effective gene stewardship and new generation breeding materials, complemented by active surveillance and monitoring, have helped to limit major epidemics and increase grain yield potential in key target environments.
In the same issue, an article by Caiyun Lui et al. discusses the application of spectral reflectance indices (SRIs) as proxies to screen for yield potential and heat stress, which is emerging in crop breeding programs. The results of a recent study, which evaluated 287 elite lines, highlight the utility of SRIs as proxies for grain yield. High heritability estimates and the identification of marker-trait associations indicate that SRIs are useful tools for understanding the genetic basis of agronomic and physiological traits.
An ongoing projectwas praised for its swift progress in the
fight against wheat blast in Bangladesh and South Asia
a mid-term review event last month at the BRAC Learning Centre in Dinajpur,
Bangladesh, professionals from the Bangladesh Ministry of Agriculture, the
Bangladesh Wheat and Maize Research Institute (BWMRI), the Bangladesh
Agriculture Research Institute (BARI), the Department of Agriculture Extension
(DAE), the Krishi Gobeshona Foundation (KGF), the Bangladesh Agriculture
Development Corporation (BADC) and the International Maize and Wheat
Improvement Center (CIMMYT) discussed progress made in the battle against wheat
blast in Bangladesh and South Asia.
Wheat blast is a fast-acting and devastating fungal disease that threatens wheat production and food security in South America and South Asia. The disease, which originated in South America and first appeared in Bangladesh in 2016, can by dispersed by wind across large distances and spores can be seed borne. There is deep concern among scientists that the disease could spread further across South Asia. A 2018 ex-ante analysis found that in Bangladesh, India and Pakistan wheat blast could potentially cause losses of 0.89 – 1.77 million tons each year, with 7 million hectares of growing area at risk.
The project, funded by the Australian Centre for International Agricultural Research (ACIAR) addresses wheat blast in Bangladesh and South Asia through the identification of new sources of resistance genes for wheat blast and development of wheat blast resistant varieties. The germplasm, genes and markers, and genetic information developed through the project are shared with South Asian national wheat breeding programs and other researchers, finally ending up in farmers’ fields as resistant varieties.
review meeting was chaired by BWMRI Director General Israil Hossain, and
featured remarks by Bangladesh’s Additional Secretary of the Ministry of
Agriculture Kamala Ranjan Das.
project has over-delivered on its milestones,” said Eric Huttner, ACIAR
Research Program Manager and lead of the review. “It’s very likely that the
project will reduce the risk of blast on wheat production in Bangladesh.”
impacts in terms of research capacity and infrastructure are very clear:
The project-established precision phenotyping platform in Jashore
— the first of its kind in Bangladesh and the region — is running at full capacity, screening for
blast in wheat germplasm materials from as far away as China, the United States
and Europe. The facility currently has
the capacity to evaluate almost 5,000 wheat germplasm materials per season and
there are ongoing plans for expansion and improvement.
Sixty-nine researchers and development professionals, including 9 women,
have benefited from the capacity development activities.
Molecular research is also making progress. Pawan Singh, project
leader and head of Wheat Pathology at CIMMYT, noted that the rapid response was
possible due to collective and collaborative action by research partners in
this project and beyond.
Meeting attendees emphasized the urgency and importance of
the project, which is set to conclude in 2021, in the battle against a
fast-moving and devastating disease.
As Huttner told attendees, “Now the resistant or tolerant
materials need to be efficiently deployed for breeding high-performance wheat
varieties that reach stakeholders as early as possible.”
The world urgently needs a transformation of the global food system, leading to healthier diets for all and a drastic reduction in agriculture’s environmental impact. The major cereal grains must play a central role in this new revolution for the benefit of the world’s poorest people.
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.
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.
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.
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.
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.
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).
The Norman Borlaug International Agricultural Science and Technology Fellowship Program at Washington State University, sponsored by the U.S. Department of Agriculture, facilitates international collaboration to fight soil borne pathogens
Soil borne pathogens (SBPs) are microorganisms that thrive in the soil and attack cereal crops, notably wheat. They cause high yield losses and reduce grain quality and quantity. SBPs include nematodes, a kind of round worm — including the Heterodera species of cereal cyst nematode and Pratylenchus species of root lesion nematodes — and crown rot caused by the Fusarium species, all of which attack roots of cereal crops. Drought and monoculture farming exacerbate this damage.
chemical, biological and other options can be used to keep pathogen population
levels low, the most environmentally friendly and biologically effective method
of control is through a resistant crop variety.
However, up to now, only a few resistance genes have been identified
against the cereal cyst nematode, Heterodera filipjevi, and this resistance
is not yet present in high yielding cultivars.
For nearly 20 years, research to fight these pathogens has benefited from a productive collaboration between the International Maize and Wheat Improvement Program (CIMMYT) in Turkey and Washington State University (WSU) and the U.S. Department of Agriculture’s Agricultural Research Service (USDA-ARS) in the United States through a fellowship program named after CIMMYT founder and Green Revolution pioneer Norman Borlaug. CIMMYT wheat breeders in Turkey have been working with breeders in Pullman, Washington to find stronger resistance genes to cereal cyst nematodes identify pathotypes, and other research areas that strengthen both CIMMYT and WSU wheat breeding programs.
pathologist and Turkey Country Representative Abdelfattah Dababat has been
working with WSU and USDA-ARS since 2010. Dababat, who joined CIMMYT as a
postdoctoral student studying soil borne pathogens (SBPs) in 2009, recently
spent two months in Pullman as a Norman Borlaug International Agricultural
Science and Technology Fellow, sponsored by the U.S. Department of
Agriculture’s Agricultural Research Service (USDA-ARS). There he was able to
share CIMMYT work with members of the WSU Department of Plant Pathology,
USDA-ARS, exchange ideas with well-known pathologists, and even travel to
Cleveland, Ohio to attend the meeting of the American Phytopathological
experience at WSU has been productive and inspiring.” said Dababat. “I have
learned from some of the best minds in plant pathology, and worked on SBP
issues that plague farmers both in my region and theirs.
like to thank CIMMYT, especially Dr. Hans Braun, for the opportunity to obtain
this great fellowship visit to WSU.”
relationship was strengthened when the two institutions collaborated on a proposal
for an Ethiopian PhD student at the University of Ankara, Turkey to work on
SBPs. Through the sponsorship of a Borlaug Leadership Enhancement in
Agriculture Program (LEAP) scholarship, Elfinesh Shikur Gebremariam spent four
months at WSU in 2013-14 to learn about molecular aspects related to crown rot
diseases. She published three peer-reviewed papers in high impact factor
Paulitz, a research plant pathologist with USDA-ARS and an adjunct professor in
WSU’s Department of Plant Pathology has also been an active member in this
collaboration, contributing to two master classes on soil borne pathogens in
cereals at CIMMYT’s Turkey research station.
Paulitz has made tremendous impact in our region,” said Dababat. “He trained
more than 50 young scientists who are now in a high scientific and or
managerial positions and are contributing not only to their own food security
but also to international food security.”
SBP resistance progress and challenges
screens hundreds of wheat germplasm lines each year against SBPs at its
research station in Eskisehir, Turkey, in collaboration with the Grain Research
Development Corporation of Australia. Using association mapping, CIMMYT
researchers have been able to identify new sources of resistance to cereal cyst
nematodes, and many new lines have been approved as moderately resistant to
resistant compared known varieties. As a
result, hundreds of lines of winter and spring wheat germplasm moderately
resistant to SBPs are available.
cyst nematodes (CCN) are a persistent problem, however. Among the most damaging
nematode pests to small grain cereal production, CCN are common from the Middle
East, North Africa and Central Asia to the Pacific Northwest of the U.S. These
nematodes alone are estimated to reduce production of crops by 10% globally. Breeding for resistance is difficult because
breeders must use live nematodes to phenotype, or measure, the lines, and there
are few molecular markers linked to the resistance genes against the major CCN
species to help identify them.
CIMMYT research — involving targeted genetic exploitations, classical
selection breeding of resistant genotypes discovery of quantitative trait loci
(QTLs) associated with resistance genes, as well as recent genome-wide
association studies (GWAS) to associate nematode resistance or susceptibility
with particular regions of the genome — has seen some success. One important
source for disease-resistance genes is found in wheat’s wild relatives. So far, 11 resistance genes have been
reported. Nine of these were transferred into common wheat from its wild
relatives (like Aegilops or goat
grass, and other Triticum species) to
enhance resistance against the H. avenae
species of nematode.
Recently, CIMMYT and the University of Bonn, Germany performed GWAS on 161 winter wheat accessions and identified 11 QTL associated with resistance against the H. filipjevi species of nematode. These QTLs were intercrossed into susceptible winter wheat germplasm and the first generation material (F1) along with the parents were sent to WSU as part of the Borlaug fellowship. CIMMYT and WSU also conducted several surveys in countries including Azerbaijan and Kazakhstan to detect SBPs in cereals.
research will help both institutes to find stronger resistance genes to the
cereal cyst nematodes.
Washington State-based part of Dababat’s Borlaug fellowship is drawing to a
close, but the collaboration and relationship between the two institutions remains.
In June of next year, Paulitz will visit him in Turkey to follow up on his
international collaboration between CIMMYT and WSU shows how much progress we
can make when we work together,” said Dababat. “I look forwarding to continuing
our partnership to help farmers around the world find resistance to SBPs.”
Scientists identified significant new chromosomal regions for wheat yield and disease resistance, which will speed up global breeding efforts.
This story by Mike Listman was originally posted on CIMMYT.org
Using the full wheat genome map published in 2018, combined with data from field testing of wheat breeding lines in multiple countries, an international team of scientists has identified significant new chromosomal regions for wheat yield and disease resistance and created a freely-available collection of genetic information and markers for more than 40,000 wheat lines.
Reported today in Nature Genetics, the results will speed up global efforts to breed more productive and climate-resilient varieties of bread wheat, a critical crop for world food security that is under threat from rising temperatures, rapidly-evolving fungal pathogens, and more frequent droughts, according to Philomin Juliana, wheat scientist at the International Maize and Wheat Improvement Center (CIMMYT) and first author of the new study.
“This work directly connects the wheat genome reference map with wheat lines and extensive field data from CIMMYT’s global wheat breeding network,” said Juliana. “That network in turn links to over 200 breeding programs and research centers worldwide and contributes to yield and other key traits in varieties sown on nearly half the world’s wheat lands.”
The staple food for more than 2.5 billion people, wheat provides 20% of human dietary calories and protein worldwide and is critical for the nutrition and food security of hundreds of millions of poor persons in regions such as North Africa and South Asia.
“Farmers and societies today face new challenges to feed rising and rapidly-urbanizing populations, and wheat epitomizes the issues,” said Ravi Singh, CIMMYT wheat breeder and corresponding author of the study. “Higher temperatures are holding back yields in major wheat-growing areas, extreme weather events are common, crop diseases are spreading and becoming more virulent, and soil and water are being depleted.”
Juliana said the study results help pave the way to apply genomic selection, an approach that has transformed dairy cow husbandry, for more efficient wheat breeding.
“Molecular markers are getting cheaper to use; meanwhile, it’s very costly to do field testing and selection involving many thousands of wheat plants over successive generations,” Juliana said. “Genome-wide marker-based selection can help breeders to precisely identify good lines in early breeding generations and to test plantlets in greenhouses, thereby complementing and streamlining field testing.”
The new study found that genomic selection could be particularly effective in breeding for wheat end-use quality and for resistance to stem rust disease, whose causal pathogen has been evolving and spreading in the form of highly-virulent new races.
The new study also documents the effectiveness of the global public breeding efforts by CIMMYT and partners, showing that improved wheat varieties from this work have accumulated multiple gene variants that favor higher yields, according to Hans-Joachim Braun, director of CIMMYT’s global wheat program.
“This international collaboration, which is the world’s largest publicly-funded wheat breeding program, benefits farmers worldwide and offers high-quality wheat lines that are released directly to farmers in countries, such as Afghanistan, that are unable to run a full-fledged wheat breeding program,” Braun explained.
The study results are expected to support future gene discovery, molecular breeding, and gene editing in wheat, Braun said.
Together with more resource-efficient cropping systems, high-yielding and climate-resilient wheat varieties will constitute a key component of the sustainable intensification of food production described in Strategy 3 of the recent EAT-Lancet Commission recommendations to transform the global food system. Large-scale genomics will play a key role in developing these varieties and staying ahead of climate- and disease-related threats to food security.
Funders of this work include USAID’s Feed the Future Innovation Lab for Applied Wheat Genomics. Contributing to the research described are research teams engaged in wheat improvement at CIMMYT, and the lab of Jesse Poland, Associate Professor at Kansas State University and Director of the USAID Applied Wheat Genomics Innovation Lab.
This story by Matt Hayes was originally posted on the Borlaug Global Rust Initiative website.
In the worst years of the rust disease epidemic that decimated North American wheat fields in the 1950s, fungal spores riding wind currents across the continent reached into the sextillions — that’s a number with 21 zeros.
Severe wheat disease epidemics produce staggering numbers of spores containing incredible genetic diversity — and incalculable risks to global food supplies. If fungal spores encounter even a single susceptible wheat variety, natural selection positions the pathogen to take hold and proliferate, releasing more rounds of spores and spreading its own virulence genes across entire populations.
Wheat breeders face a daunting task trying to defend against such a relentless barrage of evolving pathogens. In the battle, scientific ingenuity confronts biological innovation: wheat varieties that contain single disease-resistant genes can be easily overrun by rapidly evolving spores.
To safeguard food supplies and ensure durable disease resistance in wheat, scientists must embrace a globally integrated strategy that deploys resistant genes in a coordinated way, according to Maricelis Acevedo, associate director of science for the Delivering Genetic Gain in Wheat (DGGW) project.
“We need to be smart about gene deployment,” Acevedo said at the All India Wheat and Barley meeting Aug. 25 in Indore, Madhya Pradesh.
“If we don’t change our mentality, we risk reliving the worst horrors of the past and the widespread hunger that results when rust diseases wipe out the wheat supply,” she said.
Acevedo cautioned that the release of susceptible or vulnerable varieties at a national level weakens wheat resistance on a global scale. Varieties with only one major effective resistance gene, which may appear adequate to withstand disease pressure in a field trial, are at increased risk to disease pressure when released into circulation. Varieties with only a single resistance gene risk tainting an otherwise effective gene for everybody and imperiling the wheat crop around the world.
Varieties with five to six disease-resistance genes make it mathematically unlikely that spores will have the genetic ability to defeat the resistance. Minnesota scientists in 1985 calculated that the probability a pathogen contains virulence to all six major genes is more than four times greater than the number of spores released in a single year in the US under stem rust epidemic levels.
To reduce the chances of selection in pathogen populations, often caused by major genes, breeders exploit combinations of genes that may provide partial resistance to a broader number of races.
While only releasing varieties with stacked genes is the most prudent breeding strategy, there are factors that incentivize shortcuts, according to Acevedo. Plant breeders in some countries are often promoted based on the numbers of varieties released — not for their long-term usefulness. And, in some countries, there are political incentives to provide farmers with new varieties year after year rather than release fewer, but more durable varieties.
Teams of plant breeders employed by National Agricultural Research Systems in countries around the world develop improved crop varieties. Many wheat breeders receive lines from CIMMYT, the International Maize and Wheat Improvement Center, which national scientists then cross with local varieties to adapt to local conditions. National scientists also breed their own from existing local varieties. The process to develop and release any new variety can take up to ten years and up to 15 years to make it to farmers fields.
“A way to make varieties more durable for resistance to rusts is to use marker-assisted introgression of multiple resistance genes using speed breeding in recent varieties or promising varietal candidates, which also possess some of the known durable adult-plant resistance genes,” said Ravi Singh, distinguished scientist and head of Global Wheat Improvement at CIMMYT. The All India Wheat and Barley meeting was co-sponsored by CIMMYT and the International Center for Agricultural Research in the Dry Areas (ICARDA).
The Borlaug Global Rust Initiative (BGRI) was established at Cornell to reduce the world’s vulnerability to stem, yellow and leaf rusts of wheat. Acevedo said the BGRI’s main impacts have resulted from scientific collaboration, commitment to pathogen monitoring, and development and deployment of rust resistant varieties. The BGRI established a Gene Stewardship Award in 2012 to encourage the release of varieties with complex and diverse disease resistance.
In 2018, the Indian Council of Agricultural Research (ICAR), in New Delhi, India, and associated institutions, received the BGRI Gene Stewardship Award in part for replacing susceptible wheat varieties with resistant varieties.
Those efforts have proven successful: on Aug. 24, in a reported delivered at the All India Wheat and Barley meeting, ICAR announced that India for the first time produced more than 100 million tons of wheat in a year.
DGGW is funded by the Bill & Melinda Gates Foundation and UK Aid by the British people.
In February 2019 filmmaker Chris Knight of International Programs at Cornell University’s College of Agriculture and Life Sciences visited the Kenya Agricultural and Livestock Research Organization – Food Crops Research Institute (KALRO – FCRI) research station in Njoro, Kenya. Wanting to visually capture how Cornell is working with CIMMYT and a global partnership of more than 25 countries to protect the world’s wheat from diseases and the stress of climate change, he produced the short film Protecting the World’s Wheat – Delivering Genetic Gain in Kenya .
The film features East Africa, a center of genetic diversity for wheat stem rust, a fungal pathogen that causes significant yield losses worldwide. To combat this, partner countries test more than 50,000 experimental wheat lines against stem rust in Kenya every year at the Njoro research station to ensure that newly released wheat varieties will be resistant to emerging virulent races of the stem rust fungus as they evolve and spread.
Farmers and scientists have been fighting stem rust since the domestication of wheat thousands of years ago. This brilliant dance between humans and nature will likely never stop, but by working together we can stay one step ahead of this pesky pathogen. As Ruth Wanyera, Principal Research Scientist at KALRO stated, “(Stem rust) is running, and we’re also running. It’s running, and we’re also running. We have to do something to make sure there’s food in the table. That is where my motivation is. Let’s do something. Let’s feed the world. Let there be food for people to eat, or for people to survive.”