As staple foods, maize and wheat provide vital nutrients and health benefits, making up close to two-thirds of the worldâs food energy intake, and contributing 55 to 70 percent of the total calories in the diets of people living in developing countries, according to the U.N. Food and Agriculture Organization. CIMMYT scientists tackle food insecurity through improved nutrient-rich, high-yielding varieties and sustainable agronomic practices, ensuring that those who most depend on agriculture have enough to make a living and feed their families. The U.N. projects that the global population will increase to more than 9 billion people by 2050, which means that the successes and failures of wheat and maize farmers will continue to have a crucial impact on food security. Findings by the Intergovernmental Panel on Climate Change, which show heat waves could occur more often and mean global surface temperatures could rise by up to 5 degrees Celsius throughout the century, indicate that increasing yield alone will be insufficient to meet future demand for food.
Achieving widespread food and nutritional security for the worldâs poorest people is more complex than simply boosting production. Biofortification of maize and wheat helps increase the vitamins and minerals in these key crops. CIMMYT helps families grow and eat provitamin A enriched maize, zinc-enhanced maize and wheat varieties, and quality protein maize. CIMMYT also works on improving food health and safety, by reducing mycotoxin levels in the global food chain. Mycotoxins are produced by fungi that colonize in food crops, and cause health problems or even death in humans or animals. Worldwide, CIMMYT helps train food processors to reduce fungal contamination in maize, and promotes affordable technologies and training to detect mycotoxins and reduce exposure.
A seed vendor near Islamabad, Pakistan. For improved crop varieties to reach the farmers who need them, they usually must first reach local vendors, who form an essential link in the chain between researchers, seed producers and farmers. (Photo: M. DeFreese/CIMMYT)
Wheat is not just an essential part of the Pakistani diet, but also absolutely critical to the countryâs economy and to the farmers who cultivate it. The government of Pakistanâs goal to achieve self-sufficiency in wheat production just became more attainable with the release of five new wheat varieties. These new seeds could help the countryâs 8.8 million hectares of wheat-farmed area become more productive, climate-resilient and disease-resistant â a welcome development in a region where new climate change scenarios threaten sustained wheat production.
With multiple years of on-station and on-farm testing, the Wheat Research Institute (WRI) in Faisalabad, the Arid Zone Research Institute (AZRI) in Bhakhar, and the Barani Agricultural Research Institute in Chakwal released five varieties: Subhani 2021, MH-2021, Dilkash-2021, Bhakkar-20 and MA-2020.
The varieties, drawn from germplasm from the International Maize and Wheat Improvement Center (CIMMYT), were developed for different production environments in the Punjab province of Pakistan.
Dilkash-2021 was developed by WRI from a cross with a locally developed wheat line and a CIMMYT wheat line. MH-2021 and MA-2020 were selected from the CIMMYT wheat breeding germplasm through international trials and nurseries.
Subhani-21 and MA-2020 were selected from special trials assembled by CIMMYT for expanded testing, early access and genomic selection under the USAID-funded Feed the Future Innovation Lab for Applied Wheat Genomics at Kansas State University, in partnership with Cornell University and four South Asian countries (Bangladesh, India, Nepal and Pakistan).
Over the course of multiple years and locations, the new varieties exhibited a yield potential that is 5 to 20% higher than current popular varieties such as Faisalabad 2008, in addition to good grain quality and attainable yields of over 7 tons per hectare. They also showed an impressive resistance to leaf and yellow rusts, compatibility with wheat-rice and wheat-cotton farming systems, and resilience to stresses.
âIt is exciting to see new varieties coming out of these collaborative projects between the Pakistani breeding programs, CIMMYT and the university teams,â said Jesse Poland, associate professor at Kansas State University and director of the Wheat Genomics Innovation Lab.
Wheat breeder and WRI director Javed Ahmad (center, wearing a white cap) explains the performance of a new variety and its positive traits to visitors. (Photo: Muhammad Shahbaz Rafiq)
Closing the yield gap between research fields and smallholder fields
Despite all of these encouraging traits, releasing a new variety is just half of the battle. The other half is getting these new, quality seeds to markets quickly so that wheat growers can realize the benefits. A fast-track seed multiplication program for each of these varieties has been designed and implemented.
âPakistan has started to multiply early-generation seeds of rust-resistant varieties. These will be available to seed companies for multiplication and provision to farmers in the shortest possible time,â agreed wheat breeder and WRI Director Javed Ahmad and the National Wheat Coordinator Atiq Rattu.
Wheat breeder and WRI director Javed Ahmad (left) discusses performance of the new varieties with a colleague. (Photo: Muhammad Shahbaz Rafiq)
However, the current seed replacement rate is still low, mainly because new, quality seeds are rarely available at the right time, location, quantity, and price for smallholders. Strengthening and diversifying seed production of newly released varieties can be done by decentralizing seed marketing and distribution systems and engaging both public and private sector actors. Additionally, marketing and training efforts need to be improved for women, who are mostly responsible for household-level seed production and seed care.
In 2020, Pakistan harvested 25.7 million tons of wheat, up from 23.3 million tons a decade ago in 2010, which roughly matches its annual consumption of the crop. Pakistan is coming close to its goal of self-sufficiency, as outlined in the Pakistan Vision 2025, Food Security Policy 2018 and Vision for Agriculture 2030. Research shows that the public sector cannot extensively disseminate seeds alone; new policies must create an attractive environment to private sector partners, so that entrepreneurs are also attracted to the seed business. With continued efforts and a bold distribution and training effort, new releases like these will contribute to narrowing the yield gap between research stations and farmersâ fields.
Wheat infected with the blast fungus in Meherpur, Bangladesh, in 2019. (Photo: PLOS Biology)
As scientists study and learn more about the complicated genetic makeup of the wheat genome, one chromosomal segment has stood out, particularly in efforts to breed high-yielding wheat varieties resistant to devastating and quickly spreading wheat diseases.
Known as the 2NvS translocation, this segment on the wheat genome has been associated with grain yield, tolerance to wheat stems bending over or lodging, and multiple-disease resistance.
Now, thanks to a new multi-institution study led by wheat scientist Liangliang Gao of Kansas State University, we have a clearer picture of the yield advantage and disease resistance conferred by this chromosomal segment for wheat farmers â and more opportunities to capitalize on these benefits for future breeding efforts.
The Aegilops ventricosa 2NvS segment in bread wheat: cytology, genomics and breeding, published in Theoretical and Applied Genetics, summarizes the collaborative effort by scientists from several scientific institutions â including International Maize and Wheat Improvement Center (CIMMYT) head of global wheat improvement Ravi Singh and wheat scientist Philomin Juliana â Â to conduct the first complete cytological characterization of the 2NvS translocation.
A rich background
The 2NvS translocation segment has been very valuable in disease-resistance wheat breeding since the early 1990s. Originally introduced into wheat cultivar VPM1 by the French cytogeneticist Gerard Doussinault in 1983 by crossing with a wild wheat relative called Aegilops ventricosa, the segment has been conferring resistance to diseases like eye spot (Pch1 gene), leaf rust (Lr37 gene), stem rust (Sr38 gene), stripe rust (Yr17 gene), cereal cyst (Cre5 gene), root knot (Rkn3 gene) and wheat blast.
The high-yielding blast-resistant CIMMYT-derived varieties BARI Gom 33 and WMRI#3 (equivalent to Borlaug100),released in Bangladesh to combat a devastating outbreak of wheat blast in the region, carry the 2NvS translocation segment for blast resistance.
Earlier research by Juliana and others found that the proportion of lines with the 2NvS translocation had increased by 113.8% over seven years in CIMMYTâs international bread wheat screening nurseries: from 44% in 2012 to 94.1% in 2019. It had also increased by 524.3% in the semi-arid wheat screening nurseries: from 15% in 2012 to 93.7% in 2019. This study validates these findings, further demonstrating an increasing frequency of the 2NvS translocation in spring and winter wheat breeding programs over the past two decades.
New discoveries
The authors of this study completed a novel assembly and functional annotation of the genes in the 2NvS translocation using the winter bread wheat cultivar Jagger. They validated it using the spring wheat cultivar CDC Stanley and estimated the actual size of the segment to be approximately 33 mega base pairs.
Their findings substantiate that the 2NvS region is rich in disease resistance genes, with more thanâ10% of the 535 high-confidence genes annotated in this region belonging to the nucleotide-binding leucine-rich repeat (NLR) gene families known to be associated with disease resistance. This was a higher number of NLRs compared to the wheat segment of the Chinese Spring reference genome that was replaced by this segment, adding further evidence to its multiple-disease resistant nature.
In addition to being an invaluable region for disease resistance, the study makes a strong case that the 2NvS region also confers a yield advantage. Â The authors performed yield association analyses using yield data on lines from the Kansas State University wheat breeding program, the USDA Regional Performance Nursery âcomprising lines from central US winter wheat breeding programs â and the CIMMYT spring bread wheat breeding program, and found a strong association between the presence of the segment and higher yield.
Global benefits
The yield and disease resistance associations of the 2NvS genetic segment have been helping farmers for years, as seen in the high proportion of the segment present in the improved wheat germplasm distributed globally through CIMMYTâs nurseries.
âThe high frequency of the valuable 2NvS translocation in CIMMYTâs internationally distributed germplasm demonstrates well how CIMMYT has served as a key disseminator of lines with this translocation globally that would have likely contributed to a large impact on global wheat production,â said study co-author Juliana.
Through CIMMYTâs distribution efforts, it is likely that national breeding programs have also effectively used this translocation, in addition to releasing many 2NvS-carrying varieties selected directly from CIMMYT distributed nurseries.
With this study, we now know more about why the segment is so ubiquitous and have more tools at our disposal to use it more deliberately to raise yield and combat disease for wheat farmers into the future.
The new interactive map allows visitors to visually explore the milestones that allowed a global network of researchers to fight threats to wheat production.
In 2005, preeminent wheat breeder and Nobel Laureate Norman E. Borlaug sounded the alarm to bring the worldâs attention to the outbreak of a new variant of stem rust, Ug99, that threatened to wipe out 80% of the worldâs wheat.
The result was the Borlaug Global Rust Initiative (BGRI), a global community that pioneered innovative ways for scientists and smallholder farmers around the globe to collaborate on meeting challenges brought about by wheat disease and climate change.
As a founding member of BGRI, the International Maize and Wheat Improvement Center (CIMMYT) and, later, the CGIAR Research Program on Wheat, played a crucial role in the core work of the initiative. They led breeding and large-scale international testing to develop disease resistant wheat varieties, coordinated closely with longstanding national partners to facilitate the release and spread of the varieties to farmers, and contributed to critical disease monitoring and tracking initiatives.
The BGRI has documented these efforts and related resources in a newly released interactive story map: Inside the global network safeguarding the worldâs wheat from disease and climate change. The map highlights the BGRIâs efforts from 2005 to 2020 to introduce climate-resilient, disease-resistant wheat to resource-constrained wheat growers around the world, especially in sub-Saharan Africa and South Asia.
When a disease threatens to destroy the worldâs most important food crop, who do you call?
The map highlights work undertaken by scientists on the front lines of the Durable Rust Resistance in Wheat (DRRW) and Delivering Genetic Gain in Wheat (DGGW) projects from 2005 to 2020. These achievements formed the foundation for the work that continues today under the auspices of the CIMMYT-led  Accelerating Genetic Gains In Maize and Wheat for Improved Livelihoods (AGG) project.
BGRI scientists from more than 22 national and international agricultural research centers infused resilience into wheat and largely staved off large-scale rust epidemics, working with farmers in East Africa, South Asia and other important bread baskets of the world. The BGRI community improved breeding pipelines, created the worldâs most sophisticated pathogen surveillance network, increased capacity in germplasm testing nurseries while conserving and sharing genetic resources, and training new generations of young scientists.
Through videos, photos, interviews, journal articles, blogs, news stories and other resources, the map allows visitors to explore the multifaceted work from hunger fighters in Australia, Canada, China, Ethiopia, India, Kenya, Mexico, Nepal, Russia, the United Kingdom, the United States and other countries.
Written and produced by BGRI cinematographer Chris Knight and associate director for communications Linda McCandless, the map is linked to multimedia and resources from contributors around the world.
The DRRW and DGGW projects received funding from the Bill & Melinda Gates Foundation, the UK Foreign, Commonwealth and Development Office, national research institutes, and Cornell University.
Accelerating Genetic Gains in Maize and Wheat for Improved Livelihoods (AGG) brings together partners in the global science community and in national agricultural research and extension systems to accelerate the development of higher-yielding varieties of maize and wheat â two of the worldâs most important staple crops. Funded by the Bill & Melinda Gates Foundation, the UK Foreign, Commonwealth & Development Office (FCDO), the U.S. Agency for International Development (USAID) and the Foundation for Food and Agriculture Research (FFAR), AGG fuses innovative methods that improve breeding efficiency and precision to produce and deliver high-yielding varieties that are climate-resilient, pest- and disease-resistant, highly nutritious, and targeted to farmersâ specific needs.Â
Research reported in this story was supported by the Foundation for Food and Agriculture Research under award number Grant ID COTF0000000001. The content of this publication is solely the responsibility of the authors and does not necessarily represent the official views of the Foundation for Food and Agriculture Research.
The food security and livelihoods of smallholder farming families in sub-Saharan Africa depend on maize production. The region accounts for up to two-thirds of global maize production, but is facing challenges related to extreme weather events, climate-induced stresses, pests and diseases, and deteriorating soil quality. These require swift interventions and innovations to safeguard maize yields and quality.
In this Q&A, we reflect on the results and impact of the long-term collaborative work on drought-tolerant maize innovations spearheaded by two CGIAR Research Centers: the International Maize and Wheat Improvement Center (CIMMYT) and International Institute of Tropical Agriculture (IITA). This innovative work has changed guises over the years, from the early work of the Drought Tolerant Maize for Africa (DTMA) and Drought Tolerant Maize for Africa Seed Scaling (DTMASS) projects through later iterations such as Stress Tolerant Maize for Africa (STMA) and the newest project, Accelerating Genetic Gains in Maize and Wheat (AGG).
In this Q&A, three leaders of this collaborative research reflect on the challenges their work has faced, the innovations and impact it has generated for smallholder farmers, and possible directions for future research. They are: B.M Prasanna, director of CIMMYTâs Global Maize Program and of the CGIAR Research Program on Maize (MAIZE); Abebe Menkir, a maize breeder and maize improvement lead at IITA; and Cosmos Magorokosho, project lead for AGG-Maize at CIMMYT.
Briefly describe the challenges confronting small-scale farmers prior to the introduction of drought-tolerant maize and how CIMMYT and IITA responded to these challenges?
B.M.P.: Maize is grown on over 38 million hectares in sub-Saharan Africa, accounting for 40% of cereal production in the region and providing at least 30% of the populationâs total calorie intake. The crop is predominantly grown under rainfed conditions by resource-constrained smallholder farmers who often face erratic rainfall, poor soil fertility, increasing incidence of climatic extremes â especially drought and heat â and the threat of devastating diseases and insect pests.
Around 40% of maize-growing areas in sub-Saharan Africa face occasional drought stress with a yield loss of 10â25%. An additional 25% of the maize crop suffers frequent drought, with yield losses of up to 50%. Climate change is further exacerbating the situation, with devastating effects on the food security and livelihoods of the millions of smallholder farmers and their families who depend on maize in sub-Saharan Africa. Therefore, the improved maize varieties with drought tolerance, disease resistance and other farmer-preferred traits developed and deployed by CIMMYT and IITA over the last ten years in partnership with an array of national partners and seed companies across sub-Saharan Africa are critical in effectively tackling this major challenge.
A.M.: Consumption of maize as food varies considerably across sub-Saharan Africa, exceeding 100 kg per capita per year in many countries in southern Africa. In years when rainfall is adequate, virtually all maize consumed for food is grown in sub-Saharan Africa, with a minimal dependence on imported grain. Maize production, however, is highly variable from year to year due to the occurrence of drought and the dependence of national maize yields on seasonal rainfall. One consequence has been widespread famine occurring every five to ten years in sub-Saharan Africa, accompanied by large volumes of imported maize grain as food aid or direct imports.
This places a significant strain on resources of the World Food Programme and on national foreign exchange. It also disincentivizes local food production and may not prevent or address cyclical famine. It also leaves countries ill-equipped to address famine conditions in the period between the onset of the crisis and the arrival of food aid. Investment in local production, which would strengthen the resilience and self-sufficiency in food production of smallholder farming families, is a far better option to mitigate food shortages than relying on food aid and grain imports.
C.M.: Smallholder farmers in sub-Saharan Africa face innumerable natural and socioeconomic constraints. CIMMYT, in partnership with IITA and national agricultural research system partners, responded by developing and catalyzing the commercialization of new maize varieties that produce reasonable maize yields under unpredictable rainfall-dependent growing season.
Over the life of the partnership, more than 300 new climate-adaptive maize varieties were developed and released in more than 20 countries across sub-Saharan Africa where maize is a major staple food crop. Certified seed of over 100 stress-tolerant improved maize varieties have been produced by seed company partners, reaching more than 110,000 tons in 2019. The seeds of these drought-tolerant maize varieties have benefited more than 8 million households and were estimated to be grown on more than 5 million hectares in eastern, southern and west Africa in 2020.
A farmer in Mozambique stands for a photograph next to her drought-tolerant maize harvest. (Photo: CIMMYT)
In what ways did the drought-tolerant maize innovation transform small-scale farmersâ ability to respond to climate-induced risks? Are there any additional impacts on small scale farmers in addition to climate adaptation?
B.M.P.: The elite drought-tolerant maize varieties can not only provide increased yield in drought-stressed crop seasons, they also offer much needed yield stability. This means better performance than non-drought-tolerant varieties in both good years and bad years to a smallholder farmer.
Drought-tolerant maize varieties developed by CIMMYT and IITA demonstrate at least 25-30% grain yield advantage over non-drought-tolerant maize varieties in sub-Saharan Africa under drought stress at flowering. This translates into at least a 1 ton per hectare enhanced grain yield on average, as well as reduced downside risk in terms of lost income, food insecurity and other risks associated with crop yield variability. In addition to climate adaptation, smallholder farmers benefit from these varieties due to improved resistance to major diseases like maize lethal necrosis and parasitic weeds like Striga. We have also developed drought-tolerant maize varieties with enhanced protein quality â such as Quality Protein Maize or QPM â and provitamin A, which improve nutritional outcomes.
We must also note that drought risk in sub-Saharan Africa has multiple and far-reaching consequences. It reduces incentives for smallholder farmers to intensify maize-based systems and for commercial seed companies to invest and evolve due to a limited seed market.
Drought-tolerant maize is, therefore, a game changer as it reduces the downside risk for both farmers and seed companies and increases demand for improved maize seed, thus strengthening the commercial seed market in sub-Saharan Africa. Extensive public-private partnerships around drought-tolerant maize varieties supported the nascent seed sector in sub-Saharan Africa and has enabled maize-based seed companies to significantly grow over the last decade. Seed companies in turn are investing in marketing drought-tolerant maize varieties and taking the products to scale.
A.M.: The DTMA and STMA projects were jointly implemented by CIMMYT and IITA in partnership with diverse national and private sector partners in major maize producing countries in eastern, southern and western Africa to develop and deploy multiple stress-tolerant and productive maize varieties to help farmers adapt to recurrent droughts and other stresses including climate change.
These projects catalyzed the release and commercialization of numerous stress-resilient new maize varieties in target countries across Africa. Increasing the resilience of farming systems means that smallholder farmers need guaranteed access to good quality stress resilient maize seeds. To this end, the two projects worked with public and private sector partners to produce large quantities of certified seeds with a continual supply of breeder seeds from CIMMYT and IITA. The availability of considerable amount of certified seeds of resilient maize varieties has enabled partners to reach farmers producing maize under stressful conditions, thus contributing to the mitigation of food shortages that affect poor people the most in both rural and urban areas.
C.M.: The drought-tolerant maize innovation stabilized maize production under drought stress conditions in sub-Saharan Africa countries. Recent study results showed that households that grew drought-tolerant maize varieties had at least half a ton more maize harvest than the households that did not grow the drought-tolerant maize varieties, thus curbing food insecurity while simultaneously increasing farmersâ economic benefits. Besides the benefit from drought-tolerant innovation, the new maize varieties developed through the partnership also stabilized farmersâ yields under major diseases, Striga infestation, and poor soil fertility prevalent in sub-Saharan Africa.
How is the project addressing emerging challenges in breeding for drought-tolerant maize and what opportunities are available to address these challenges in the future?Â
Margaret holds an improved ear of drought-tolerant maize. Margaretâs grandmother participated in an on-farm trial in Murewa district, 75 kilometers northeast of Zimbabweâs capital Harare. (Photo: Jill Cairns/CIMMYT)
B.M.P.: A strong pipeline of elite, multiple-stress-tolerant maize varieties â combining other relevant adaptive and farmer-preferred traits â has been built in sub-Saharan Africa through a strong germplasm base, partnerships with national research partners and small- and medium-sized seed companies, an extensive phenotyping and multi-location testing network, and engagement with farming communities through regional on-farm trials for the identification of relevant farmer-preferred products.
CGIAR maize breeding in sub-Saharan Africa continues to evolve in order to more effectively and efficiently create value for the farmers we serve. We are now intensively working on several areas: (a) increasing genetic gains (both on-station and on-farm) through maize breeding in the stress-prone environments of sub-Saharan Africa by optimizing our breeding pipelines and effectively integrating novel tools, technologies and strategies (e.g., doubled haploids, genomics-assisted breeding, high-throughput and precise phenotyping, improved breeding data management system, etc.); (b) targeted replacement of old or obsolete maize varieties in sub-Saharan Africa with climate-adaptive and new varieties; (c) developing next-generation climate-adaptive maize varieties with traits such as native genetic resistance to fall armyworm, and introgressed nutritional quality traits (e.g., provitamin A, high Zinc) to make a positive impact on the nutritional well-being of consumers; and (d) further strengthening the breeding capacity of national partners and small and medium-sized seed companies in sub-Saharan Africa for a sustainable way forward.
A.M.:Â The DTMA and STMA projects established effective product pipelines integrating cutting-edge phenotyping and molecular tools to develop stress-resilient maize varieties that are also resistant or tolerant to MLN disease and fall armyworm. These new varieties are awaiting release and commercialization. Increased investment in strengthening public and private sector partnerships is needed to speed up the uptake and commercialization of new multiple stress-resilient maize varieties that can replace the old ones in farmersâ fields and help achieve higher yield gains.
Farmersâ access to new multiple-stress-tolerant maize varieties will have a significant impact on productivity at the farm level. This will largely be due to new varietiesâ improved response to fertilizer and favorable growing environments as well as their resilience to stressful production conditions. Studies show that the adoption of drought-tolerant maize varieties increased maize productivity, reduced exposure to farming risk among adopters and led to a decline in poverty among adopters. The availability of enough grain from highly productive and stress-resilient maize varieties can be the cheapest source of food and release land to expand the cultivation of other crops to facilitate increased access to diversified and healthy diets.
C.M.: Â The project is tackling emerging challenges posed by new diseases and pests by building upon the successful genetic base of drought-tolerant maize. This is being done by breeding new varieties that add tolerance to the emerging disease and pest challenges onto the existing drought-tolerant maize backgrounds. Successes have already been registered in breeding new varieties that have high levels of resistance to MLN disease and the fall armyworm pest.
Opportunities are also available to address new challenges including: pre-emptively breeding for threats to maize production challenges that exist in other regions of the world before these threats reach sub-Saharan Africa; enhancing the capacity of national partners to build strong breeding programs that can address new threats once they emerge in sub-Saharan Africa; and sharing knowledge and novel high-value breeding materials across different geographies to immediately address new threats once they emerge.
Cover photo: Alice Nasiyimu stands in front of a drought-tolerant maize plot at her family farm in Bungoma County, in western Kenya. (Photo: Joshua Masinde/CIMMYT)
Sanjaya Rajaram at the Centro de Investigaciones AgrĂcolas del Noroeste (CIANO) in Ciudad ObregĂłn, in Mexicoâs Sonora state. (Photo: Gil Olmos/CIMMYT)
With great sorrow, we report the passing of Sanjaya Rajaram, former Wheat Program director and distinguished scientist at the International Maize and Wheat Improvement Center (CIMMYT), in Mexico on February 17, 2021, at the age of 78. Rajaram was one of the most successful and influential wheat breeders ever, and was distinguished with the World Food Prize in 2014.
As leader of bread wheat breeding and later director of CIMMYTâs Global Wheat Program, Rajaram â affectionately known by his colleagues as âRajâ â personally oversaw the development of more than 480 high-yielding, disease-resistant varieties sown on 58 million hectares in 51 countries, increasing global wheat production by more than 200 million tons during his lifetime in diverse regions across the globe.
âAt CIMMYT, we all remember Raj as a great and humble colleague helping the team to perform at the highest levels of science with impact. Many of us within CIMMYT, as well in national programs worldwide, have been inspired by him,â said Martin Kropff, CIMMYT Director General. âWe will also remember him as a friend who cared for others and treated all people alike.â
âDr. Rajaram built a generation of wheat breeders at CIMMYT, ICARDA and national research institutions, who are carrying on his legacy and ensuring that new wheat varieties continue to reach farmers. We will deeply miss his presence and encouragement,â said Ravi Singh, head of the Wheat Improvement program once led by Rajaram.
Norman Borlaug (right) in the field with Sanjaya Rajaram, his successor as head of CIMMYT’s wheat program. (Photo: Gene Hettel/CIMMYT)
Hans Braun (center), Sanjaya Rajaram (third from right), Ravi Singh (first from right) and other colleagues stand for a photograph during a field day at CIMMYTâs experimental station in Ciudad ObregĂłn, Sonora, Mexico. (Photo: CIMMYT)
Sanjaya Rajaram (right) speaks during a field day for scientists and staff at the CIMMYT experimental station in Toluca, Mexico, in 2013. (Photo: CIMMYT)
The World Food Prize 2014 was awarded to Sanjaya Rajaram for his achievements in plant research and food production. (Photo: RajaramS, CC BY-SA 4.0, via Wikimedia Commons)
Sanjaya Rajaram speaks at the 2015 BGRI Workshop in Sydney, Australia. (Photo: Christopher Knight/CIMMYT)
Sanjaya Rajaram speaks at the event to celebrate CIMMYTâs 50th anniversary in 2014. (Photo: Gerardo MejĂa/CIMMYT)
A life devoted to wheat breeding
Born on a small farm in India in 1943, Rajaram studied genetics and plant breeding at the Indian Agricultural Research Institute in New Delhi. After receiving his Ph.D. from the University of Sydney, he joined CIMMYT in 1969, diligently working as a wheat breeder alongside Nobel Prize Laureate and scientist Norman Borlaug in Mexico. Recognizing his talent and initiative, Borlaug appointed Rajaram as head of CIMMYTâs wheat breeding program at just 29 years of age.
Borlaug described Rajaram as âa scientist of great vision who made a significant contribution to the improvement of world wheat production, working for the benefit of hundreds of thousands of farmers in countries across the globe.â
Among Rajaramâs many accomplishments include being awarded the prestigious World Food Prize in 2014 for his role in increasing global wheat production and alleviating world hunger. His crossing of spring and winter wheat varieties led to new advances in wheat varieties that were stable across a wide range of environments, as well as featuring high yields and resistance to wheat diseases, particularly rust and foliar blight.
In 2015, he was awarded the Pravasi Bharatiya Samman award, the highest honor conferred on Indians overseas. He also received the highly prestigious Padma Shri award from the government of India in 2001, the Friendship Award from the government of China in 1998, numerous fellowships from scientific societies and doctorates from various universities.
Rajaram recognized the importance of sharing his knowledge and cultivating the talents of the next generation of plant scientists, training and mentoring more than 700 scientists from developing countries worldwide.
Rajaram also served as Director of the Integrated Gene Management Program at the International Center for Agricultural Research in the Dry Areas (ICARDA) before formally retiring in 2008. In his retirement, he continued as a special scientific advisor to CIMMYT and ICARDA, residing in his home of Mexico.
In addition to his successful career as a plant scientist, Rajaram launched and operated Resource Seeds International, a company to study and market seed of improved wheat varieties.
The CIMMYT community sends our deepest condolences to Rajaramâs family during this period.
A maize ear harvested from a “milpa,” the maize-based intercrop that is a critical source of food and nutritional security for smallholder farming communities in remote areas such as the Western Highlands of Guatemala. (Photo: Cristian Reyna)
The traditional milpa intercrop â in which maize is grown together with beans, squash, or other vegetable crops â can furnish a vital supply of food and nutrients for marginalized, resource-poor communities in the Americas, according to a study published today in Nature Scientific Reports.
One hectare of a milpa comprising maize, common beans, and potatoes can provide the annual carbohydrate needs of more than 13 adults, enough protein for nearly 10 adults, and adequate supplies of many vitamins and minerals, according to the study. The research was based on data from nearly 1,000 households across 59 villages of the Western Highlands of Guatemala and is the first to relate milpa intercropping diversity with nutritional capacity, using multiple plots and crop combinations.
âThe milpa was the backbone of pre-Columbian agriculture in North America, Mexico, and Central America,â said Santiago LĂłpez-Ridaura, specialist in agricultural systems and climate change adaptation at the International Maize and Wheat Improvement Center (CIMMYT) and lead author of the article.
âMilpa production anchored around locally-adapted maize is still an essential food and nutritional lifeline for isolated, often indigenous communities throughout Mexico and Central America, and can be tailored to improve their food and nutritional security, along with that of small-scale farmers in similar settings,â he added.
Maize for feed or food and nutrition?
In modern times, some 1 billion tons of maize are harvested yearly from about 200 million hectares worldwide. Much of this output results from intensive monocropping of hybrids that yield an average 10 tons per hectare, in places like the U.S.
This massive world harvest goes chiefly for animal feed, corn starch, corn syrup, ethanol, and myriad industrial products, but in sub-Saharan Africa, Latin America, and parts of Asia, maize remains a critical food staple, often grown by smallholder farmers with yields averaging around 1.5 tons per hectare.
The Western Highlands of Guatemala is among the worldâs poorest regions â a mountainous area ill-served by markets and where communities battered by food insecurity and malnutrition sow crops at altitudes of up to 3,200 meters, according to Cristian A. Reyna-RamĂrez, a co-author of the study from the Universidad AutĂłnoma Metropolitana-Xochimilco, Mexico.
âFully two-thirds of farmers in this region grow milpas based on maize but varying the intercrops with potatoes, faba bean, and even fruit trees,â Reyna-RamĂrez said. âOur study showed that combinations such as maize-common bean-faba bean, maize-potatoes, and maize-common bean-potatoes provided the most carbohydrates, proteins, zinc, iron, calcium, potassium, folate, thiamin, riboflavin, vitamin B6, niacin and vitamin C.â
The classic âmilpaâ intercrop comprises maize, beans, and squash. The bean plant climbs the maize stalk to reach sunlight and its roots add nitrogen to the soil; the squash leaves shade the soil, conserving moisture and inhibiting weed growth. Milpa systems are often grown on steep hillsides at a wide range of altitudes. (Photo: Cristian Reyna)
Better diets and routes out of poverty?
With typical landholdings of less than a quarter hectare and households averaging six members, Guatemalaâs Western Highlands inhabitants cannot depend on the milpa alone to satisfy their needs, LĂłpez-Ridaura cautioned.
âAs with many smallholder farm communities, lack of land and general marginalization traps them in a vicious circle of poverty and malnutrition, forcing them to experiment with risky cash crops or for working-age members to undertake dangerous and heartbreaking migrations to find work and send back remittances,â he explains.
According to LĂłpez-Ridaura, this study points the way for tailoring milpa systems to help communities that still rely on that intercrop or others that could benefit from its use.
Looking forward
Natalia Palacios Rojas, CIMMYT maize quality and nutrition expert and a co-author of this article, notes that calculations of this and other milpa studies consider raw nutrients and that research is needed on the nutritional contributions of cooked food and non-milpa foods such as poultry, livestock, home-garden produce, and purchased food.
âFurther work should also address the effects of storing milpa produce on its nutrient stability and how the seasonal availability of milpa crops impacts diets and nutrition,â Palacios said.
The authors are grateful for funding from the United States Agency for International Development (USAID) as part of Feed the Future, the U.S. Governmentâs global hunger and food security initiative, under the Buena Milpa project, as well as the support of the CGIAR Research Program on Maize.
The Heat and Drought Wheat Improvement Consortium (HeDWIC) is a global research and capacity building network that takes wheat research from the theoretical to the practical by incorporating the best science into real-life breeding scenarios.
By harnessing the latest technologies in crop physiology, genetics and breeding, HeDWIC makes it easier for wheat scientists to work together on solutions to the complex problems of heat and drought adaptation, contributing to the development of new, climate-resilient wheat varieties for farmers. HeDWIC-associated scientists examine current breeding material and collections held in germplasm banks and apply genomic and phenomic tools to identify novel diversity for heat, drought adaptative traits. This results in novel pre-bred lines in terms of genetic diversity for key stress-adaptive traits suitable for use in breeding programs and/or re-selection as cultivars.
The consortium delivers these lines to public and private wheat programs worldwide via the International Wheat Improvement Network (IWIN) â coordinated for more than half a century by the International Maize and Wheat Improvement Center (CIMMYT) â as international public goods whose global impacts are well documented. Through PhD sponsorships and other opportunities for involvement in research, HeDWIC also provides hands-on training to young scientists, preparing a new generation of crop experts to tackle the pressing issues of crop adaptation under future climate scenarios.
HeDWIC adds value to developing more climate-resilient wheat varieties by:
Facilitating global coordination of wheat research related to heat and drought stress in partnership with the Wheat Initiative.
Developing research and breeding technologies in response to the priorities of stakeholders: researchers, breeders, farmers, seed companies, national programs, and funding organizations.
Connecting geographically and agro-climatically diverse sites for rigorous testing of promising concepts.
Curating data resources for use by the global wheat research community.
Accelerating the deployment of new knowledge and strategies for developing more climate resilient wheat.
Preparing a new generation of promising young scientists from climate-affected regions to tackle crop improvement challenges faced by their own countries.
Building additional scientific capacity of wheat researchers in a coordinated fashion that enables a faster response to productivity threats associated with climate change.
Enabling farmers to adapt to wheat production in a hotter and drier climate faster due to the coordinated effort and synergy lent by HeDWIC.
HeDWIC is directly funded by the Foundation for Food and Agriculture Research (FFAR) and is supported by in-kind contributions from IWIN, the Bill & Melinda Gates Foundation/UK Foreign, Commonwealth and Development Office (FCDO)-funded Accelerating Genetic Gains in Maize and Wheat for Improved Livelihoods (AGG) project, the CGIAR Research Program on Wheat (WHEAT), the International Wheat Yield Partnership, the Wheat Initiativeâs AHEAD, and many international partners who support research and capacity building activities through ongoing collaboration.
It also builds on decades of breeding and collaborative research under abiotic stress coordinated by CIMMYT, with support from agencies including Mexicoâs Secretariat of Agriculture and Rural Development (SADER), the CGIAR Trust Fund âin particular the Australian Centre for International Agricultural Research (ACIAR), the UK Foreign, Commonwealth and Development Office (FCDO), and the US Agency for International Development (USAID) â Australia’s Grains Research Development Corporation (GRDC), Germanyâs Ministry of Agriculture (BMEL), the Bill & Melinda Gates Foundation, the US Department of Agriculture (USDA), and others.
Evidence of enormity and immediacy of the challenges climate change poses for life on earth seems to pour in daily. But important gaps in our knowledge of all the downstream effects of this complex process remain. And the global response to these challenges is still far from adequate to the job ahead. Bold, multi-stakeholder, multidisciplinary action is urgent.
In addition to exploring the important challenges climate changes poses for plant health, the event explored the implications for the wellbeing and livelihoods of smallholder farming communities in low- and middle- income countries, paying special attention to the gender dimension of both the challenges and proposed solutions.
The event was co-organized by researchers at the International Rice Research Institute (IRRI) and the International Centre of Insect Physiology and Ecology (icipe).
The overall webinar series is hosted by the International Maize and Wheat Improvement Center (CIMMYT), the International Potato Center (CIP), the International Food Policy Research Institute (IFPRI), the International Institute of Tropical Agriculture (IITA) and the International Rice Research Institute (IRRI). It is sponsored by the CGIAR Research Program on Agriculture for Nutrition (A4NH), the CGIAR Gender Platform and the CGIAR Research Program on Roots, Tubers and Bananas (RTB).
This is important
The stakes for the conversation were forcefully articulated by Shenggen Fan, chair professor and dean of the Academy of Global Food Economics and Policy at China Agricultural University and member of the CGIAR System Board. âBecause of diseases and pests, we lose about 20-40% of our food crops. Can you imagine how much food we have lost? How many people we could feed with that lost food? Climate change will make this even worse,â Fan said.
Such impacts, of course, will not be evenly felt across geographic and social divides, notably gender. According to Jemimah Njuki, director for Africa at IFPRI, gender and household relationships shape how people respond to and are impacted by climate change. âOne of the things we have evidence of is that in times of crises, womenâs assets are often first to be sold and it takes even longer for them to be recovered,â Njuki said.
The desert locust has been around since biblical times. Climate change has contributed to its reemergence as a major pest. (Photo: David Nunn)
Shifting risks
When it comes to understanding the impact of climate change on plant health âone of our big challenges is to understand where risk will change,â said Karen Garrett, preeminent professor of plant pathology at the University of Florida,
This point was powerfully exemplified by Henri Tonnang, head of Data Management, Modelling and Geo-information Unit at icipe, who referred to the âunprecedented and massive outbreakâ of desert locusts in 2020. The pest â known since biblical times â has reemerged as a major threat due to extreme weather events driven by sea level rise.
Researchers highlighted exciting advancements in mapping, modelling and big data techniques that can help us understand these evolving risks. At the same time, they stressed the need to strengthen cooperation not only among the research community, but among all the stakeholders for any given research agenda.
âThe international research community needs to transform the way it does research,â said Ana MarĂa Loboguerrero, research director for Climate Action at the Alliance of Bioversity International and CIAT. âWeâre working in a very fragmented way, sometime inefficiently and with duplications, sometimes acting under silos⊠It is difficult to deliver end-to-end sustainable and scalable solutions.â
Time for a new strategy
Such injunctions are timely and reaffirm CGIARâs new strategic orientation. According to Sonja Vermeulen, the event moderator and the director of programs for the CGIAR System Management Organization, this strategy recognizes that stand-alone solutions â however brilliant â arenât enough to make food systems resilient. We need whole system solutions that consider plants, animals, ecosystems and people together.
Echoing Fanâs earlier rallying cry, Vermeulen said, âThis is important. Unless we do something fast and ambitious, we are not going to meet the Sustainable Development Goals.â
Cover photo: All farmers are susceptible to extreme weather events, and many are already feeling the effects of climate change. (Photo: N. Palmer/CIAT)
Australiaâs High Commissioner to India, Barry Oâ Farrell (left), observes the use of drone technology at the BISA experimental station in Ludhiana, India. (Photo: Uttam Kumar/CIMMYT).
Australiaâs High Commissioner to India, Barry OâFarrell, visited the Borlaug Institute for South Asia (BISA) in Ludhiana, India, on January 20, 2021 along with his delegation.
OâFarrell acknowledged the historic role of the International Maize and Wheat Improvement Center (CIMMYT) sharing the seeds of the most recent, climate-resilient, high-yielding, and disease-resistant wheat genotypes. He also appreciated that this work is being continued with even greater vigor by BISA for the benefit of India and the whole of South Asia.
The High Commissioner was happy to note that wheat germplasm is freely shared with public and private sector national partners under constant guidance and collaboration with the Indian Council of Agricultural Research (ICAR) and the Department of Agriculture Research and Education (DARE).
OâFarrell emphasized the strong collaboration between Indian and Australian research institutes. He called for even more cross-learning between scientists and other stakeholders for research, policy and capacity development in the areas of land, water, climatic resilience, environmental sustainability and germplasm enhancement for the benefit of farmers of both countries.
Witnessing science in action
Arun Kumar Joshi, CIMMYT Regional Representative for Asia and Managing Director of BISA, welcomed the group and briefed the visitors on CIMMYT and BISAâs collaboration with ICAR and DARE.
H.S. Sidhu, Principal Research Engineer at BISA, and M.L. Jat, Principal Scientist and Systems Agronomist at CIMMYT, presented the major challenges and research outputs related to climate change, the food-energy-water nexus and the overall agricultural sustainability challenges faced by India.
One of the successful examples of collaboration between Australia and India is the Happy Seeder, which addresses these challenges through conservation agriculture and sustainable intensification. OâFarrell saw the expansive wheat fields sown with the Happy Seeder and was impressed by the technology.
The group also discussed the evidence-based policy changes that have taken place, as well as future strategies for accelerated impact through new approaches, like carbon farming. A detailed discussion took place on climate-smart agriculture research, with a focus on precision water and nutrient management using digital agriculture technologies and their complementarity for boosting Happy Seeder uptake.
The High Commissioner and his delegation also visited the wheat breeding program, where CIMMYT researcher Uttam Kumar explained the development of wheat genotypes â in collaboration with ICAR-DARE and the national agriculture research system â for a range of environments, management conditions, and against various stresses, with the ultimate objective of serving the needs of smallholder farmers.
OâFarrell also appreciated the BISA-designed Phenocart for high-throughput precision phenotyping in wheat improvement. OâFarrell highlighted and appreciated that this season, BISA is conducting the largest wheat breeding trial in South Asia: currently more than 60,000 plots are planted at the BISA station in Ludhiana alone.
The International Maize and Wheat Improvement Center (CIMMYT) is offering a new set of elite, improved maize hybrids to partners in eastern Africa and similar agro-ecological zones. National agricultural research systems (NARS) and seed companies are invited to apply for licenses to pursue national release of, and subsequently commercialize, these new hybrids, in order to bring the benefits of the improved seed to farming communities.
The deadline to submit applications to be considered during the first round of allocations is 9 February 2021. Applications received after that deadline will be considered during the following round of product allocations.
Information about the newly available CIMMYT maize hybrids from Eastern Africa breeding program, application instructions and other relevant material is available below.
To apply, please fill out the CIMMYT Improved Maize Product Allocation Application Forms, available for download at the links below. Each applicant will need to complete one copy of Form A for their organization, then for each hybrid being requested a separate copy of Form B. (Please be sure to use these current versions of the application forms.)
Researchers from the International Maize and Wheat Improvement Center (CIMMYT) and the International Livestock Research Institute (ILRI) have identified new genomic regions associated with maize stover quality, an important by-product of maize which can be used in animal feed.
The results of the study, published this month in Nature Scientific Reports, will allow maize breeders to select for stover quality traits more quickly and cost-effectively, and to develop new dual purpose maize varieties without sacrificing grain yield.
The researchers screened diverse Asia-adapted CIMMYT maize lines from breedersâ working germplasm for animal feed quality traits. They then used these as a reference set to predict the breeding values of over a thousand doubled haploid lines derived from abiotic stress breeding programs based on genetic information. Based on these breeding values, the scientists further selected 100 of these double haploid lines and validated the performance of stover quality traits through field-based phenotyping.
The results demonstrate the feasibility of incorporating genomic prediction as a tool to improve stover traits, circumventing the need for field or lab-based phenotyping. The findings significantly reduce the need for additional testing resources â a major hindrance in breeding dual-purpose maize varieties.
Interestingly, the researchers found that increased animal feed quality in maize stover had no impact on grain yield, a concern raised by scientists in the past.
âThe main purpose of this study and overall purpose of this CIMMYT and ILRI collaboration was to optimize the potential of maize crops for farm families, increase income, improve livelihoods and sustainably manage the crop livestock system, within limited resources,â said P.H. Zaidi, a maize physiologist at CIMMYT and co-author of the study.
âMore than 70% of the farmers in the tropics are smallholders so they donât have a lot of land to grow crops for grain purposes and separate stover for animal feed, so this is a very sustainable model if they grow dual purpose maize.â
By growing maize simultaneously for both human consumption and animal feed, farmers can get the most out of their crops and conserve natural resources like land and water.
A farmer works in a maize field close to the Pusa site of the Borlaug Institute for South Asia (BISA), in the Indian state of Bihar. (Photo: M. DeFreese/CIMMYT)
Fodder for thought
The findings from this study also validate the use of genomic prediction as an important breeding tool to accelerate the development and improvement of dual-purpose maize varieties, according to CIMMYT Maize Breeder and first author of the study, M.T. Vinayan.
With the demand for animal feed increasing around the world, crop scientists and breeders have been exploring more efficient ways to improve animal feed quality in cereals without compromising grain yields for human consumption.
âNot all maize varieties have good stover quality, which is what we realized when we started working on this project. However, we discovered that there are a few which offer just as good quality as sorghum stover â a major source of livestock fodder particularly in countries such as India,â said Zaidi.
The publication of the study is a fitting tribute to the late Michael Blummel, who was a principal scientist and deputy program leader in the feed and forage development program at ILRI and co-author of this study.
âA couple of years back Dr Blummel relocated from the Hyderabad office at ILRI to its headquarters at Addis Ababa, but he used to frequently visit Hyderabad, and without fail met with us on each visit to discuss updates, especially about dual-purpose maize work. He was very passionate about dual-purpose maize research with a strong belief that the additional income from maize stover at no additional cost will significantly improve the income of maize farmers,â Zaidi said. âMichael was following this publication very closely because it was the first of its kind in terms of molecular breeding for dual purpose maize. He would have been very excited to see this published.â
A handful of improved maize seed from the drought-tolerant variety TAN 250, developed and registered for sale in Tanzania through CIMMYT’s Drought Tolerant Maize for Africa (DTMA) project, in partnership with Tanzanian seed company Tanseed International Limited. It is based on material from CIMMYT-Zimbabwe, CIMMYT-Mexico, and Tanzania. (Photo: Anne Wangalachi/CIMMYT)
The CGIAR Research Program on Maize (MAIZE) âuniquely fills a gap at the global and regional level, positioning it to continue catalyzing good science across borders,â according to a new report.
In addition to the exceptional quality of the programâs scientific inputs and the overall quality of its outputs, the reviewers note the programâs capacity to mobilize âstakeholders, resources and knowledge to rapidly deliver valuable solutions for a critical need.â The review authors specifically note MAIZEâs efforts towards halting the spread of maize lethal necrosis (MLN).
While, like all CGIAR Research Programs, MAIZE is due to conclude at the end of 2021, much of the programâs pioneering work will continue under new guises, such as the Accelerating Genetic Gains in Maize and Wheat for Improved Livelihoods (AGG) project.
MAIZE â led by CIMMYT in partnership with the International Institute of Tropical Agriculture (IITA) â spearheads international, multi-stakeholder research for development to improve the livelihoods and food security of poor maize producers and consumers. It simultaneously seeks to strengthen the sustainability of maize-based agri-food systems. The program focuses on maize production in low- to middle-income countries â accounting for approximately two-thirds of global maize production â where the crop is âkey to the food security and livelihoods of millions of poor famers,â according to the report.
âMAIZE provides a very robust platform for collaboration with our national partners, including private companies, community seed produces and other stakeholders. Through projects such as Drought Tolerant Maize for Africa (DTMA) and STMA, research has been able to provide innovative solutions to challenges that smallholder farmers face in their daily lives, such as drought, poor soils, and pests and diseases,â says Nteranya Sanginga, IITAâs Director General.
The review concludes that MAIZE âgood management and governance practice are a strong foundation for the remainder of [the programâs] running.â The reviewers also recommend that the âexcellent,â participatory application of theory of change thinking in the second phase of MAIZE be mainstreamed at the CGIAR system level moving forward. Key recommendations for the programâs final phase include:
Building on MAIZEâs âstrong network of partnersâ by deepening these relationships into âmultidirectional partnerships.â
Building on existing cross-cutting work on capacity development, climate change, gender and youth.
Diversifying and expanding MAIZEâs knowledge dissemination efforts to more deeply engage with include multiple and non-scientific audiences.
A new publication in Virus Research shows that these second-generation MLN-resistant hybrids developed by the International Maize and Wheat Improvement Center (CIMMYT) offer better yields and increased resilience against MLN and other stresses.
Scientists are calling for accelerated adoption of new hybrid maize varieties with resistance to maize lethal necrosis (MLN) disease in sub-Saharan Africa. In combination with recommended integrated pest management practices, adopting these new varieties is an important step towards safeguarding smallholder farmers against this devastating viral disease.
A new publication in Virus Research shows that these second-generation MLN-resistant hybrids developed by the International Maize and Wheat Improvement Center (CIMMYT) offer better yields and increased resilience against MLN and other stresses. The report warns that the disease remains a key threat to food security in eastern Africa and that, should containment efforts slacken, it could yet spread to new regions in sub-Saharan Africa.
The publication was co-authored by researchers at the International Maize and Wheat Improvement Center (CIMMYT), Kenya Agricultural and Livestock Research Organization (KALRO), the Alliance for a Green Revolution in Africa (AGRA), the African Agricultural Technology Foundation (AATF) and Aarhus University in Denmark.
CIMMYT technician Janet Kimunye (right) shows visitors a plant with MLN symptoms at the MLN screening facility in Naivasha, Kenya. (Photo: CIMMYT)
Stemming the panic
The first reported outbreak of MLN in Bomet County, Kenya in 2011 threw the maize sector into a panic. The disease caused up to 100% yield loss. Nearly all elite commercial maize varieties on the market at the time were susceptible, whether under natural of artificial conditions. Since 2012, CIMMYT, in partnership with KALRO, national plant protection organizations and commercial seed companies, has led multi-stakeholder, multi-disciplinary efforts to curb MLNâs spread across sub-Saharan Africa. Other partners in this endeavor include the International Institute of Tropical Agriculture (IITA), non-government organizations such as AGRA and AATF, and advanced research institutions in the United States and Europe.
In 2013 CIMMYT established an MLN screening facility in Naivasha. Researchers developed an MLN-severity scale, ranging from 1 to 9, to compare varietiesâ resistance or susceptibility to the disease. A score of 1 represents a highly resistant variety with no visible symptoms of the disease, while a score of 9 signifies extreme susceptibility. Trials at this facility demonstrated that some of CIMMYTâs pre-commercial hybrids exhibited moderate MLN-tolerance, with a score of 5 on the MLN-severity scale. CIMMYT then provided seed and detailed information to partners for evaluation under accelerated National Performance Trials (NPTs) for varietal release and commercialization in Kenya, Tanzania and Uganda.
Between 2013 and 2014, four CIMMYT-derived MLN-tolerant hybrid varieties were released by public and private sector partners in East Africa. With an average MLN severity score of 5-6, these varieties outperformed commercial MLN-sensitive hybrids, which averaged MLN severity scores above 7. Later, CIMMYT breeders developed second-generation MLN-resistant hybrids with MLN severity scores of 3â4. These second-generation hybrids were evaluated under national performance trials. This led to the release of several hybrids, especially in Kenya, over the course of a five-year period starting in 2013. They were earmarked for commercialization in East Africa beginning in 2020.
Maize Lethal Necrosis (MLN) sensitive and resistant hybrid demo plots in Naivashaâs quarantine & screening facility (Photo: KIPENZ/CIMMYT)
Widespread adoption critical
The last known outbreak of MLN was reported in 2014 in Ethiopia, marking an important break in the virusâs spread across the continent. Up to that point, the virus had affected the Democratic Republic of the Congo, Kenya, Rwanda, Tanzania and Uganda. However, much remains to be done to minimize the possibility of future outbreaks.
âDue to its complex and multi-faceted nature, effectively combating the incidence, spread and adverse effects of MLN in Africa requires vigorous and well-coordinated efforts by multiple institutions,â said B.M. Prasanna, primary author of the report and director of the Global Maize Program at CIMMYT and of the CGIAR Research Program on Maize (MAIZE). Prasanna also warns that most commercial maize varieties being cultivated in eastern Africa are still MLN-susceptible. They also serve as âreservoirsâ for MLN-causing viruses, especially the maize chlorotic mottle virus (MCMV), which combines with other viruses from the Potyviridae family to cause MLN.
âThis is why it is very important to adopt an integrated disease management approach, which encompasses extensive adoption of improved MLN-resistant maize varieties, especially second-generation, not just in MLN-prevalent countries but also in the non-endemic ones in sub-Saharan Africa,â Prasanna noted.
The report outlines other important prevention and control measures including: the production and exchange of âcleanâ commercial maize seed with no contamination by MLN-causing viruses; avoiding maize monocultures and continuous maize cropping; practicing maize crop rotation with compatible crops, especially legumes, which do not serve as hosts for MCMV; and continued MLN disease monitoring and surveillance.
L.M. Suresh (center-right), Maize Pathologist at CIMMYT and Head of the MLN Screening Facility, facilitates a training on MLN with national partners. (Photo: CIMMYT)
Noteworthy wins
In addition to the development of MLN-resistant varieties, the fight against MLN has delivered important wins for both farmers and their families and for seed companies. In the early years of the outbreak, most local and regional seed companies did not understand the disease well enough to produce MLN-pathogen free seed. Since then, CIMMYT and its partners developed standard operating procedures and checklists for MLN pathogen-free seed production along the seed value chain. Today over 30 seed companies in Ethiopia, Kenya, Uganda, Rwanda and Tanzania are implementing these protocols on a voluntary basis.
âMLN represents a good example where a successful, large-scale surveillance system for an emerging transboundary disease has been developed as part of a rapid response mechanism led by a CGIAR center,â Prasanna said.
Yet, he noted, significant effort and resources are still required to keep the maize fields of endemic countries free of MLN-causing viruses. Sustaining these efforts is critical to the âfood security, income and livelihoods of resource-poor smallholder farmers.
To keep up with the diseaseâs changing dynamics, CIMMYT and its partners are moving ahead with novel techniques to achieve MLN resistance more quickly and cheaply. Some of these innovative techniques include genomic selection, molecular markers, marker-assisted backcrossing, and gene editing. These techniques will be instrumental in developing elite hybrids equipped not only to resist MLN but also to tolerate rapidly changing climatic conditions.
Cover photo: Researchers and visitors listen to explanations during a tour of infected maize fields at the MLN screening facility in Naivasha, Kenya. (Photo: CIMMYT)
Byrd C. Curtis, director of CIMMYT’s Global Wheat Program from 1982 to 1988. (Photo: CIMMYT)
The International Maize and Wheat Improvement Center (CIMMYT) sadly notes the passing of Byrd C. Curtis, former Director of the Global Wheat Program, on January 7. He was 95 years old and lived in Fort Collins, Colorado, USA, with his wife Eloise Curtis.
From his studies at Oklahoma State University to retiring after a fruitful international career with Colorado State University, Cargill Inc. and CIMMYT, he never got weary of sharing his passion for breeding better, tastier and sturdier wheat to improve peoplesâ livelihoods.
He was an innovator at heart and his legacy will live on through Colorado State Universityâs wheat breeding program and the many wheat varieties he developed. Not only did he start Colorado State Universityâs wheat breeding program in 1963, but he also ensured that the varieties that were bred by his team reflected the needs of humanity for decades to come, such as the hard, red winter wheat variety named after himself.
Curtis worked at CIMMYT from 1982 and 1988 as Director of the Global Wheat Program. Together with his team, he worked to position CIMMYT as the leading international research-for-development and breeding organization for wheat for years to come.
âByrd was very keen to build oral communication skills of scientists, which has been very helpful to me,â said Ravi Singh, Head of Global Wheat Improvement at CIMMYT. âHe also initiated the Turkey-CIMMYT-ICARDA International Winter Wheat Improvement Partnershipâs (IWWIP) winter wheat breeding program and even worked there in Turkey in his final year with CIMMYT to ensure it would take off well.â
Byrd was instrumental and showed tremendous foresight. IWWIPâs establishment in Turkey became first major breeding program within CGIAR that was hosted by a national program. He strongly supported the creation of the Wide Crossing Program. The synthetic wheat varieties developed in this program have had global impact on wheat improvement.
Aside from his remarkable technical legacy, Byrd had a knack for choosing the right people for the job. In the six years as Director of the Global Wheat Program, he hired scientists who held major roles in global wheat improvement: Ravi Singh, Distinguished Scientist and Head of Global Wheat Improvement; Wolfgang Pfeiffer, former leader of spring bread wheat, durum wheat, and triticale crop improvement; and Hans Braun, Director of the Global Wheat Program from 2004 to 2020.
âByrd not only initiated the winter wheat program,â said former Global Wheat Program Director Hans Braun, who was hired by Byrd in 1983. âHe was also director when the tropical wheat program was implemented in Thailand.â This programâs work increased yields up to 1.5 tons per hectare but ultimately did not convince Thai farmers. Nevertheless, Braun said, âOne of the oddest experiences Iâve had was to see our winter wheat material from Turkey grown in the Thai jungle!â
After retiring from his professional life in 1991, Curtis and his wife Eloise moved back to Fort Collins, where his career started in the 1960s and where he will be remembered by his townspeople â and fellow athletes and gym-goers â for his determination and active lifestyle.
The CIMMYT community sends its deepest sympathies and wishes for peace to the Curtis family.
The International Maize and Wheat Improvement Center (CIMMYT) is offering a new set of elite, improved maize hybrids to partners in eastern Africa and similar agro-ecological zones. National agricultural research systems (NARS) and seed companies are invited to apply for licenses to pursue national release of, and subsequently commercialize, these new hybrids, in order to bring the benefits of the improved seed to farming communities.
