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Ravi Singh earns Lifetime Achievement award from BGRI

CIMMYT distinguished scientist Ravi Singh conducts research on a wheat field while. (Photo: BGRI)
CIMMYT distinguished scientist Ravi Singh conducts research on a wheat field while. (Photo: BGRI)

World-renowned plant breeder Ravi Singh, whose elite wheat varieties reduced the risk of a global pandemic and now feed hundreds of millions of people around the world, has been announced as the 2021 Borlaug Global Rust Initiative (BGRI) Lifetime Achievement Award recipient.

Singh, distinguished scientist and head of Global Wheat Improvement at the International Maize and Wheat Improvement Center (CIMMYT), endowed hundreds of modern wheat varieties with durable resistance to fungal pathogens that cause leaf rust, stem rust, stripe rust and other diseases during his career. His scientific efforts protect wheat from new races of some of agriculture’s oldest and most devastating diseases, safeguard the livelihoods of smallholder farmers in the most vulnerable areas in the world, and enhance food security for the billions of people whose daily nutrition depends on wheat consumption.

“Ravi’s innovations as a scientific leader not only made the Cornell University-led Borlaug Global Rust Initiative possible, but his breeding innovations are chiefly responsible for the BGRI’s great success,” said Ronnie Coffman, vice chair of the BGRI and international professor of global development at Cornell’s College of Agriculture and Life Sciences. “Perhaps more than any other individual, Ravi has furthered Norman Borlaug’s and the BGRI’s goal that we maintain the global wheat scientific community and continue the crucial task of working together across international borders for wheat security.”

In the early 2000s, when a highly virulent rust race discovered in East Africa threatened most of the world’s wheat, Singh took a key leadership role in the formation of a global scientific coalition to combat the threat. Along with Borlaug, Coffman and other scientists, he served as a panel member on the pivotal report alerting the international community to the Ug99 outbreak and its potential impacts to global food security. That sounding of the alarm spurred the creation of the BGRI and the collaborative international effort to stop Ug99 before it could take hold on a global scale.

As a scientific objective leader for the BGRI’s Durable Rust Resistance in Wheat and Delivering Genetic Gain in Wheat projects, Singh led efforts to generate and share a series of elite wheat lines featuring durable resistance to all three rusts. The results since 2008 include resistance to the 12 races of the Ug99 lineage and new, high-temperature-tolerant races of stripe rust fungus that had been evolving and spreading worldwide since the beginning of the 21st century.

“Thanks to Ravi Singh’s vision and applied science, the dire global threat of Ug99 and other rusts has been averted, fulfilling Dr. Borlaug’s fervent wishes to sustain wheat productivity growth, and contributing to the economic and environmental benefits from reduced fungicide use,” Coffman said. “Ravi’s innovative research team at CIMMYT offered crucial global resources to stop the spread of Ug99 and the avert the human catastrophe that would have resulted.”

An innovative wheat breeder known for his inexhaustible knowledge and attention to genetic detail, Singh helped establish the practice of “pyramiding” multiple rust-resistance genes into a single variety to confer immunity. This practice of adding complex resistance in a way that makes it difficult for evolving pathogens to overcome new varieties of wheat now forms the backbone of rust resistance breeding at CIMMYT and other national programs.

Ravi Singh (center) with Norman Borlaug (left) and Hans Braun in the wheat fields at CIMMYT’s experimental station in Ciudad Obregón, in Mexico’s Sonora state. (Photo: CIMMYT)
Ravi Singh (center) with Norman Borlaug (left) and Hans Braun in the wheat fields at CIMMYT’s experimental station in Ciudad Obregón, in Mexico’s Sonora state. (Photo: CIMMYT)

The global champion for durable resistance

Ravi joined CIMMYT in 1983 and was tasked by his supervisor, mentor and friend, the late World Food Prize Winner Sanjaya Rajaram, to develop wheat lines with durable resistance, said Hans Braun, former director of CIMMYT’s Global Wheat Program.

“Ravi did this painstaking work — to combine recessive resistance genes — for two decades as a rust geneticist and, as leader of CIMMYT’s Global Spring Wheat Program, he transferred them at large scale into elite lines that are now grown worldwide,” Braun said. “Thanks to Ravi and his colleagues, there has been no major rust epidemic in the Global South for years, a cornerstone for global wheat security.”

Alison Bentley, Director of CIMMYT’s Global Wheat Program, said that “Building on Ravi’s exceptional work throughout his career, deployment of durable rust resistance in widely adapted wheat germplasm continues to be a foundation of CIMMYT’s wheat breeding strategy.”

Revered for his determination and work ethic throughout his career, Singh has contributed to the development of 649 wheat varieties released in 48 countries, working closely with scientists at national wheat programs in the Global South. Those varieties today are sown on approximately 30 million hectares annually in nearly all wheat growing countries of southern and West Asia, Africa and Latin America. Of these varieties, 224 were developed directly under his leadership and are grown on an estimated 10 million hectares each year.

In his career Singh has authored 328 refereed journal articles and reviews, 32 book chapters and extension publications, and more than 80 symposia presentations. He is regularly ranked in the top 1% of cited researchers. The CIMMYT team that Singh leads identified and designated 22 genes in wheat for resistance or tolerance to stem rust, leaf rust, stripe rust, powdery mildew, barley yellow dwarf virus, spot blotch, and wheat blast, as well as characterizing various other important wheat genome locations contributing to durable resistance in wheat.

Singh’s impact as a plant breeder and steward of genetic resources over the past four decades has been extraordinary, according to Braun: “Ravi Singh can definitely be called the global champion for durable resistance.”

This piece by Matt Hayes was originally posted on the BGRI website.

How do we sustainably manage transboundary diseases and crop pests?

In our hyper-connected world, it should come as no surprise that recent years have shown a major uptick in the spread of transboundary pests and diseases. Integrated approaches have been effective in sustainably managing these border-jumping threats to farmers’ livelihoods and food security.

But a truly integrated approach accounts for not just the “cure,” but also how it can be sustainably incorporated into the agri-food system and social landscape.  For example, how do we know if the farmers who adopt disease- and pest-resistant seed will be able to derive better incomes? And how do we ensure that incentives are aligning with community norms and values to enable better adoption of integrated disease or pest management approaches?

Experts from across the CGIAR research system and its partners weighed in on this topic in the recent webinar on Integrated Pest and Disease Management, the third in the International Year of Plant Health Webinar series. Panelists shared valuable perspectives on the science of outbreaks, the social dimensions of crop pest and disease control, zoonotic disease risk, and how national, regional and global organizations can better coordinate their responses.

“The combination of science, global partnerships and knowledge helps all of us be better prepared to avoid the losses we’ve seen. . . Today, we’re going to see what this looks like in practice,” said Rob Bertram, chief scientist for the Bureau for Resilience and Food Security at USAID, and moderator of the event.

Participants on the webinar on Integrated Pest and Disease Management. (Photo: CIMMYT)
Participants on the webinar on Integrated Pest and Disease Management. (Photo: CIMMYT)

Understanding the sources

Wheat and maize, the key crops studied at the International Maize and Wheat Improvement Center (CIMMYT) are no stranger to destructive  diseases or pests, with fall armyworm, wheat blast, or maize lethal necrosis topping the list. But other staple crops and their respective economies are suffering as well — from infestations of cassava brown streak, potato cyst nematode, taro blight, desert locusts, and fusarium wilt, just to name a few.

What are the reasons for the expansion of these outbreaks? B.M. Prasanna, director of CIMMYT’s Global Maize Program explained that there are several: “Infected seed or planting material, vector movement, strong migratory capacity, contaminated field equipment, improper crop production commercialization practices, and global air and sea traffic” are all major causes.

Prevention and control of diseases and pests requires an integral strategy which mobilizes synergies of multiple institutions. (Graphic: B.M. Prasanna/CIMMYT)
Prevention and control of diseases and pests requires an integral strategy which mobilizes synergies of multiple institutions. (Graphic: B.M. Prasanna/CIMMYT)

Preventing outbreaks is always better than scrambling to find a cure, but as Prasanna pointed out, this requires a holistic, multi-institutional strategy including surveillance and early warning, quarantine and phytosanitary regulations, and technological solutions. Better access to monitoring and surveillance data, and sensitive, easy-to-use and affordable diagnostic equipment are essential, as is the proactive deployment of resistant crop varieties.

Building awareness about integrated disease and pest management is just as important, he told the attendees. “We must remember that IPM is not just Integrated Pest Management, but also ‘Integrating People’s Mindsets.’ That remains a major challenge. We need to think beyond our narrow disciplines and institutions and really come together to put IPM solutions into farmers’ fields,” Prasanna said.

Not all outbreaks are the same, but lessons can be shared

Regina Eddy, coordinator for the Fall Armyworm Interagency Task Force at USAID, works closely with the complex issue of scaling when it comes to disaster response and the roles of national, regional and global organizations.

“We need to develop inclusive partner stakeholder platforms, not designed ‘for them,’ but ‘with them,’” said Eddy. “We cannot tackle food security issues alone. Full stop.”

Closing the gap between social and biophysical science

Nozomi Kawarazuka, social anthropologist at the International Potato Center (CIP) explained how researchers can improve the uptake of their new seed, innovation, or agronomic practice by involving social scientists to understand the gender norms and social landscape at the beginning of the project — in the initial assessment phase.

Kawarazuka highlighted how involving women experts and extension workers in sectors that are typically male-dominated helps reduce bias and works towards changing perceptions.

“In South Asia, women farmers hesitate to engage with male government extension workers,” she said. “Women experts and extension workers reduce this barrier. Gender and social diversity in the plant health sector is an entry point to develop innovations that are acceptable to women as well as men and helps scale up adoption of innovations in the community.

Gender and social dimensions of pest and disease control: a call for collaboration (Graphic: Nozomi Kawarazuka/CIP)
Gender and social dimensions of pest and disease control: a call for collaboration (Graphic: Nozomi Kawarazuka/CIP)

The world is watching agriculture and livestock

Zoonotic diseases, or zoonoses, are caused by pathogens spread between animals and people. Understanding zoonotic disease risk is an essential and timely topic in the discussion of integrated pest management. Poor livestock management practices, lack of general knowledge on diseases and unsafe yet common food handling practices put populations at risk.

“It’s especially timely, [to have this] zoonosis discussion in our COVID-plagued planet. The whole world is going to be looking to the food and agricultural sectors to do better,” Bertram said.

Annet Mulema, a gender and social scientist at the International Livestock Research Institute (ILRI) described results of a study showing how community conversations transformed gender relations and zoonotic disease risk in rural Ethiopia, where 80% of the population depends on agriculture and has direct contact with livestock.

“There were noticeable changes in attitude and practices among men and women regarding unsafe handling of animals and consumption of animal-source foods,” Mulema explained. “Community conversations give men and women involved a voice, it allows for a variety of ideas to be expressed and discussed, leads to community ownership of conclusions and action plans, and opens communication channels among local service providers and community members.”

Proportion of women and men practicing safe handling of livestock and animal source foods, before and after community conversation intervention. (Graphic: Annet Mulema/ILRI)
Proportion of women and men practicing safe handling of livestock and animal source foods, before and after community conversation intervention. (Graphic: Annet Mulema/ILRI)

Local to global, and global to local

Panelists agreed that improving capacity is the most powerful lever to advance approaches for integrated pest management and plant health, while connected and inclusive partnerships along the value chain make the whole system more resilient. The amount of scientific knowledge on ways to combat plant pests and diseases is increasing, and we have new tools to connect the global with the local and bring this knowledge to the community level.

The fourth and final CGIAR webinar on plant health is scheduled for March 31 and will focus on a the intersectional health of people, animals, plants and their environments in a “One Health” approach.

CGIAR webinar unleashes multidisciplinary approach to climate change and plant health

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.

Mindful of this, the first event in Unleashing the Potential of Plant Health, a CGIAR webinar series in celebration of the UN-designated International Year of Plant Health, tackled the complicated nexus between climate change and plant health. The webinar, titled “Climate change and plant health: impact, implications and the role of research for adaptation and mitigation,” convened a diverse panel of researchers from across the CGIAR system and over 900 audience members and participants.

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. “Because 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,” 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. “One of the things we have evidence of is that in times of crises, women’s assets are often first to be sold and it takes even longer for them to be recovered,” 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)
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 “one of our big challenges is to understand where risk will change,” 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 “unprecedented and massive outbreak” of desert locusts in 2020. The pest — known since biblical times — 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.

“The international research community needs to transform the way it does research,” said Ana María Loboguerrero, research director for Climate Action at the Alliance of Bioversity International and CIAT. “We’re 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.”

Time for a new strategy

Such injunctions are timely and reaffirm CGIAR’s 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 — however brilliant — aren’t enough to make food systems resilient. We need whole system solutions that consider plants, animals, ecosystems and people together.

Echoing Fan’s earlier rallying cry, Vermeulen said, “This is important. Unless we do something fast and ambitious, we are not going to meet the Sustainable Development Goals.”

Register for the other webinars in the series

Cover photo: All farmers are susceptible to extreme weather events, and many are already feeling the effects of climate change. (Photo: N. Palmer/CIAT)

Fast-tracked adoption of second-generation resistant maize varieties key to managing maize lethal necrosis in Africa

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)
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 MLN’s 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 varieties’ 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 CIMMYT’s 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 3–4. 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 Naivasha’s quarantine & screening facility (Photo: KIPENZ/CIMMYT)
Maize Lethal Necrosis (MLN) sensitive and resistant hybrid demo plots in Naivasha’s 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 virus’s 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.

“Due 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,” 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 “reservoirs” for MLN-causing viruses, especially the maize chlorotic mottle virus (MCMV), which combines with other viruses from the Potyviridae family to cause MLN.

“This 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,” Prasanna noted.

The report outlines other important prevention and control measures including: the production and exchange of “clean” 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)
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.

“MLN 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,” 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 “food security, income and livelihoods of resource-poor smallholder farmers.

To keep up with the disease’s 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.

Read the full report on Virus Research:
Maize lethal necrosis (MLN): Efforts toward containing the spread and impact of a devastating transboundary disease in sub-Saharan Africa

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)

“Let there be food to eat”

“We want to feed the people, we don’t want them to go hungry. We have to do something to make sure there is food on the table. That is where my motivation is… Let there be food to eat.”

— Ruth Wanyera, 2019

The International Maize and Wheat Improvement Center (CIMMYT) has long attributed its widespread impact and reach to strong collaborations with national agricultural research systems (NARS) around the world. Today, CIMMYT — and especially the Global Wheat Program and the CGIAR Research Program on Wheat — wish to honor one long-term collaborator whose work and dedication to wheat research has had abiding positive effects beyond her home region of sub-Saharan Africa.

Ruth Wanyera, national wheat research program coordinator at the Kenya Agricultural and Livestock Research Organization (KALRO), has spent her more than 30-year career dedicated to plant protection research, fueled by her motivation to “feed the people.” She was one of the first scientists to recognize stem rust in east Africa and has been one of CIMMYT’s strongest allies in fighting the devastating wheat disease, stem rust Ug99.

Wanyera recently won both the Norman Borlaug Lifetime Achievement Award from the Borlaug Global Rust Initiative and the Kenya Agricultural Research (KARA) Award at the High Panel Conference on Agricultural Research in Kenya. Wanyera’s team at KALRO has also been recognized with the prestigious Borlaug Global Rust Initiative (BGRI) Gene Stewardship Award.

National Wheat Coordinator Ruth Wanyera (third from right) gives a lesson to pathology interns in the field of a fungicide efficiency trial at KALRO Njoro Research Station, Nakuru, Kenya.
National Wheat Coordinator Ruth Wanyera (third from right) gives a lesson to pathology interns in the field of a fungicide efficiency trial at KALRO Njoro Research Station, Nakuru, Kenya. (Photo:CIMMYT)

A long-term relationship with CIMMYT

Sridhar Bhavani, senior scientist and head of Rust Pathology and Molecular Genetics at CIMMYT has worked closely with Wanyera and her team since the mid-2000s.

“Ruth is a passionate researcher who has tirelessly dedicated her entire career to cereal pathology, and as a team, we coordinated the stem rust phenotyping platform for over a decade and had great successes on multiple international projects,” he said.

CIMMYT’s relationship with Wanyera’s team strengthened when Nobel Prize Laureate Norman Borlaug visited the Kenyan research facility to observe the emerging threat of stem rust. Upon witnessing how serious the outbreak had become, Borlaug organized an emergency summit in Nairobi in 2005, famously “sounding the alarm” for swift and concerted action on stem rust, and ultimately leading to the establishment of the BGRI.

“Ruth and her team of dedicated scientists from KALRO have not only made Kenya proud but have also made a remarkable contribution to the global wheat community in mitigating the threat of stem rust Ug99,” says Bhavani. “Ruth has mentored master’s and PhD students who are now leading researchers at KALRO. She has elevated the research capacity of KALRO to international repute.”

Two recent wheat breeding projects helped extend the CIMMYT-KALRO partnership beyond Kenya. The Durable Rust Resistance in Wheat (DRRW) and Delivering Genetic Gain in Wheat (DGGW) projects brought in a partnership with the Ethiopia Institute for Agricultural Research (EIAR) to establish and operate stem rust phenotyping platforms that addressed the global threat of Ug99 and other serious stem rust races, and helped provide solutions for the region. Thanks to KALRO’s screening efforts at the CIMMYT-KALRO Stem Rust Screening Platform in Njoro, Kenya, CIMMYT-derived rust-resistant varieties now cover more than 90% of the wheat farming area in Kenya and Ethiopia.

Ruth Wanyera receives the Kenya Agricultural Research Award (KARA), during the High Panel Conference on Agricultural Research in Kenya. (Photo: CIMMYT)
Ruth Wanyera receives the Kenya Agricultural Research Award (KARA), during the High Panel Conference on Agricultural Research in Kenya. (Photo: CIMMYT)

The partnership continues to grow

Continued collaboration with Ruth’s team at KALRO will be essential in the new Accelerating Genetic Gains in Maize and Wheat for Improved Livelihoods (AGG) project. AGG — which aims to accelerate the development and delivery of more productive, climate-resilient, gender-responsive, market-demanded, and nutritious wheat varieties in in sub-Saharan Africa and South Asia — has a particular focus on enhanced collaboration with national partners such as KALRO.

Its success is also closely tied to the Njoro Stem Rust Screening Platform — which, since its establishment in 2008, has conducted crucial screening for over 600,000 wheat lines, varieties, varietal candidates, germplasm bank accessions and mapping populations. Wanyera’s leadership in the Platform, alongside that of CIMMYT wheat scientist Mandeep Randhawa,  plays a major role in screening, monitoring, and clearing seed in time for sowing.

As Hans Braun, former director of the CIMMYT Global Wheat Program said, “Without our national agriculture research system partnerships, CIMMYT would become obsolete.”

Indeed, the unparalleled wealth of knowledge, skills, and research facilities of the CGIAR as a whole would not be so uniquely impactful if it weren’t for the 3000+ partnerships with national governments, academic institutions, enthusiastic farmers, private companies and NGOs that help carry out this work.

CIMMYT’s historic and continued impact depends on close international partnerships with scientists and leaders like Ruth Wanyera, and we congratulate her on her numerous awards, thank her for her collaboration, and wish her a pleasant retirement.

Wheat disease common to South America jumps to Africa

Pawan Kumar Singh, head, wheat pathology, International Maize and Wheat Improvement Center (CIMMYT) says that the fast-acting and devastating fungal disease known as wheat blast was first spotted in Africa in the Zambian rainfed wheat production system in the 2017-2018 crop cycle.

Read more here: https://www.scidev.net/sub-saharan-africa/agriculture/news/wheat-disease-common-to-asia-jumps-to-africa.html

Wheat blast has made the intercontinental jump to Africa

For the first time, wheat blast, a fast-acting and devastating fungal disease, has been reported on the African continent, according to a new article published by scientists from the Zambian Agricultural Research Institute (ZARI), the International Maize and Wheat Improvement Center (CIMMYT) and the US Department of Agriculture – Foreign Disease Weed Science Research Unit (USDA-ARS).

Read more: https://www.rural21.com/english/scientific-world/detail/article/wheat-blast-has-made-the-intercontinental-jump-to-africa.html

Scientists find genomic regions associated with wheat blast resistance in CIMMYT nurseries

Wheat spike damaged by wheat blast.
Wheat blast damages wheat spikes. (Photo: Xinyao He / CIMMYT)

In an article published in Nature Scientific Reports, a team of scientists led by wheat breeder Philomin Juliana from the International Wheat and Maize Improvement Center (CIMMYT) conducted a large genome-wide association study to look for genomic regions that could also be associated with resistance to wheat blast.

Juliana and fellow scientists found 36 significant markers on chromosome 2AS, 3BL, 4AL and 7BL that appeared to be consistently associated with blast resistance across different environments. Among these, 20 markers were found to be in the position of the 2NS translocation, a chromosomal segment transferred to wheat from a wild relative, Aegilops ventricosa, that has very strong and effective resistance to wheat blast.

The team also gained excellent insights into the blast resistance of the globally-distributed CIMMYT germplasm by genomic fingerprinting a panel over 4,000 wheat lines for the presence of the 2NS translocation, and found that it was present in 94.1% of lines from International Bread Wheat Screening Nurseries (IBWSNs) and 93.7% of lines from Semi-Arid Wheat Screening Nurseries (SAWSNs). Although it is reassuring that such a high percentage of CIMMYT wheat lines already have the 2NS translocation and implied blast resistance, finding other novel resistance genes will be instrumental in building widespread, global resilience to wheat blast outbreaks in the long-term.

The researchers used data collected over the last two years from CIMMYT’s IBWSNs and SAWSNs by collaborators at the Bangladesh Wheat and Maize Research Institute (BWMRI) and Bolivia’s Instituto Nacional de Innovación Agropecuaria y Forestal (INIAF).

Devastating fungal disease

Wheat blast, caused by the fungus Magnaporthe oryzae pathotype Triticum, was first identified in 1985 in South America, but has been seen in Bangladesh in recent years. The expansion of the disease is a great concern for regions of similar environmental conditions in South Asia, and other regions globally.

Although management of the disease using fungicide is possible, it is not completely effective for multiple reasons, including inefficiency during high disease pressure, resistance of the fungal populations to some classes of fungicides, and the affordability of fungicide to resource-poor farmers. Scientists see the development and deployment of wheat with genetic resistance to blast as the most sustainable and farmer-friendly approach to preventing devastating outbreaks around the world.

This work was made possible by the generous support of the Delivering Genetic Gains in Wheat (DGGW) project funded by the Bill & Melinda Gates Foundation, the U.K. Foreign, Commonwealth & Development Office (FCDO) and managed by Cornell University, the U.S. Agency for International Development’s Feed the Future initiative, the CGIAR Research Program on Wheat (WHEAT), the Indian Council of Agricultural Research (ICAR), The Swedish Research Council (Vetenskapsråd), and the Australian Centre for International Agricultural Research (ACIAR).

Read the full article:
Genome‑wide association mapping for wheat blast resistance in CIMMYT’s international screening nurseries evaluated in Bolivia and Bangladesh

This story was originally posted on the website of the CGIAR Research Program on Wheat (wheat.org).

Wheat blast has made the intercontinental jump to Africa

Scientists observe wheat blast in Zambia's Mpika district. (Photo: Batiseba Tembo/ZARI)
Scientists observe wheat blast in Zambia’s Mpika district. (Photo: Batiseba Tembo/ZARI)

Wheat blast, a fast-acting and devastating fungal disease, has been reported for the first time on the African continent. In an article published in the scientific journal PLoS One, a team of scientists confirmed that symptoms of wheat blast first appeared in Zambia during the 2018 rainy season, in experimental plots and small-scale farms in the Mpika district, Muchinga province.

Researchers from the International Maize and Wheat Improvement Center (CIMMYT), the US Department of Agriculture – Foreign Disease Weed Science Research Unit (USDA-ARS) and the Zambian Agricultural Research Institute (ZARI) participated in this study.

Wheat blast poses a serious threat to rain-fed wheat production in Zambia and raises the alarm for surrounding regions and countries on the African continent with similar environmental conditions. Worldwide, 2.5 billion consumers depend on wheat as a staple food and, in recent years, several African countries have been actively working towards reducing dependence on wheat imports.

“This presents yet another challenging biotic constraint to rain-fed wheat production in Zambia,” said Batiseba Tembo, wheat breeder at ZARI and lead scientist on the study.

A difficult diagnosis

Researchers from ZARI check for wheat blast in experimental plots. (Photo: Batiseba Tembo/ZARI)
Researchers from ZARI check for wheat blast in experimental plots. (Photo: Batiseba Tembo/ZARI)

“The first occurrence of the disease was very distressing. This happened at the spike stage, and caused significant losses,” Tembo said. “Nothing of this nature has happened before in Zambia.”

Researchers were initially confused when symptoms of the disease were first reported in the fields of Mpika. Zambia has unique agro-climatic conditions, particularly in the rainfed wheat production system, and diseases such as spot blotch and Fusarium head blight are common.

“The crop had silvery white spikes and a green canopy, resulting in shriveled grains or no grains at all… Within the span of seven days, a whole field can be attacked,” Tembo explained. Samples were collected and analyzed in the ZARI laboratory, and suspicions grew among researchers that this may be a new disease entirely.

Tembo participated in the Basic Wheat Improvement Course at CIMMYT’s global headquarters in Mexico, where she discussed the new disease with Pawan Singh, head of Wheat Pathology at CIMMYT. Singh worked with Tembo to provide guidance and the molecular markers needed for the sample analysis in Zambia, and coordinated the analysis of the wheat disease samples at the USDA-ARS facility in Fort Detrick, Maryland, United States.

All experiments confirmed the presence of the fungus Magnaporthe oryzae pathotype Triticum (MoT), which causes the disease.

“This is a disaster which needs immediate attention,” Tembo said. “Otherwise, wheat blast has the potential to marginalize the growth of rain-fed wheat production in Zambia and may threaten wheat production in neighboring countries as well.”

Wheat blast spreads through infected seeds and crop residues, as well as by spores that can travel long distances in the air. The spread of blast within Zambia is indicated by both mechanisms of expansion.

Wheat blast has expanded rapidly since it was initially discovered in Brazil in 1985. (Map: Kai Sonder/CIMMYT)
Wheat blast has expanded rapidly since it was initially discovered in Brazil in 1985. (Map: Kai Sonder/CIMMYT)

A cause for innovation and collaboration

CIMMYT and the CGIAR Research Program on Wheat (WHEAT) are taking action on several fronts to combat wheat blast. Trainings and international courses invite participants to gain new technical skills and knowledge in blast diagnostics, treatment and mitigation strategies. WHEAT scientists and partners are also studying the genetic factors that increase resistance to the disease and developing early warning systems.

“A set of research outcomes, including the development of resistant varieties, identification of effective fungicides, agronomic measures, and new findings in the epidemiology of disease development will be helpful in mitigating wheat blast in Zambia,” Singh said.

“It is imperative that the regional and global scientific communities join hands to determine effective measures to halt further spread of this worrisome disease in Zambia and beyond,” Tembo expressed.


Read the study:

Detection and characterization of fungus (Magnaporthe oryzae pathotype Triticum) causing wheat blast disease on rain-fed grown wheat (Triticum aestivum L.) in Zambia

Interview opportunities:

Pawan Kumar Singh, Senior Scientist and Head of Wheat Pathology, International Maize and Wheat Improvement Center (CIMMYT)

Batiseba Tembo, Wheat Breeder, Zambian Agricultural Research Institute (ZARI)

For more information, or to arrange interviews, contact the media team:

Rodrigo Ordóñez, Communications Manager, CIMMYT. r.ordonez@cgiar.org

Acknowledgements

Financial support for this research was provided by the Zambia Agriculture Research Institute (ZARI), the CGIAR Research Program on Wheat (WHEAT), the Australian Centre for International Agricultural Research (ACIAR), and the US Department of Agriculture’s Agricultural Research Service (USDA-ARS). 

The Basic Wheat Training Program and Wheat Blast Training is made possible by support from investors including the Australian Centre for International Agricultural Research (ACIAR), WHEAT, the Indian Council of Agricultural Research (ICAR), Krishi Gobeshona Foundation (KGF), the Swedish Research Council (SRC) and the United States Agency for International Development (USAID).

The Accelerating Genetic Gains in Maize and Wheat (AGG) project is funded by the Bill & Melinda Gates Foundation, the UK Foreign, Commonwealth & Development Office, the United States Agency for International Development and the Foundation for Food and Agricultural Research (FFAR).

About CIMMYT

The International Maize and What Improvement Center (CIMMYT) is the global leader in publicly-funded maize and wheat research and related farming systems. Headquartered near Mexico City, CIMMYT works with hundreds of partners throughout the developing world to sustainably increase the productivity of maize and wheat cropping systems, thus improving global food security and reducing poverty. CIMMYT is a member of the CGIAR System and leads the CGIAR programs on Maize and Wheat and the Excellence in Breeding Platform. The Center receives support from national governments, foundations, development banks and other public and private agencies. For more information visit staging.cimmyt.org.

Building resistance in wheat: International collaboration fights Septoria tritici blotch disease

Phenotypic selection of resistant lines (Ms. H. Kouki Field technician and consultant A. Yahyaoui) at the Septoria Precision Phenotyping Platform at Kodia/INGC. (Photo: Septoria Precision Phenotyping Platform)

Tunisia has been a major durum wheat producer and consumer since Roman times, a crop used now for couscous, bread and pasta dishes throughout North Africa and the Mediterranean Basin.

However, a persistent disease known as Septoria tritici blotch (STB) has been threatening durum wheat harvests across the country thanks to its increasing resistance to fungicides and adaptability to harsher climatic conditions. The disease, which is caused by the fungus Zymoseptoria tritici, thrives under humid conditions and can cause up to 60% yield loss in farmers’ fields.

To help fight this disease, the International Maize and Wheat Improvement Center (CIMMYT) established the Septoria Precision Phenotyping Platform in collaboration with the Institution of Agricultural Research and Higher Education of Tunisia (IRESA) and the International Center for Agricultural Research in the Dry Areas (ICARDA) in Tunisia in 2015.

The platform aims to accelerate the transfer of STB resistance genes into elite durum wheat lines from national and international breeding programs, particularly CIMMYT and ICARDA breeding programs. Researchers at the platform have tested an impressive diversity of durum wheat lines for resistance to the disease from research institutes across Tunisia, Morocco, Algeria, Mexico, France, Italy, the UK, USA and Canada.

STB field reactions showing typical necrotic symptoms containing pycnidia on an infected adult plant leaf of wheat. (Photo: Septoria Precision Phenotyping Platform)

“New and more virulent strains of the pathogen are constantly emerging, which results in previously resistant wheat varieties becoming more susceptible,” said Sarrah Ben M’Barek, head of the laboratory at the Septoria Precision Phenotyping platform.

Field phenotyping – the use of field-testing to identify desired plant traits — is the heart of the platform. Scientists can test as many as 30,000 plots each year for STB resistance.

Evaluations are conducted at two main field research stations managed by the Regional Field Crop Center (CRRGC) and the National Institute of Field Crops (INGC), based at two major hotspots for the disease in Beja and Kodia. This work is complemented by laboratory research at the National Agronomic Institute of Tunisia (INAT) at Tunis.

“The platform plays a critical role in identifying STB resistant wheat germplasm and characterizing the resistance genes they possess. These resistant sources be can further utilized in hybridization schemes by durum wheat breeders worldwide to develop durable resistant varieties,” explained CIMMYT consultant and platform coordinator Amor Yahyaoui.

With the help of data from the platform, breeders hope to combine multiple resistance genes in an individual variety to create a genetically complex “lock” whose combination the fungus will not easily break.

According to Ben M’Barek, the huge genetic diversity in wheat and its ancestors has helped breeders to develop new varieties for almost a century. However, the adoption of new varieties has typically been slow.

Farmers in Tunisia traditionally rely on fungicides to manage the disease. However, with the pathogen recently becoming more resistant to fungicides and more adaptive to harsher climatic conditions, interest in STB resistant varieties is increasing.

Field disease reactions of a susceptible wheat cultivar. (Photo: Septoria Precision Phenotyping Platform)

A hub for training and collaboration

The platform is also a hub for training and capacity development for national and international scientists, field research and lab. assistants, students and farmers. It brings together research staff and technicians from different institutions within Tunisia including the CRRGC, INGC, the National Institute of Agricultural Research of Tunisia (INRAT), INAT and the University of Jendouba.

Farmer’s organizations and regional extension services, as well as private organizations such as Comptoir Multiservices Agricoles (CMA), seed and chemical companies also collaborate with the platform. The result is a team effort that has generated a tremendous wealth of data, made only possible through the dedication of Yahyaoui, said Ben M’Barek.

“Spending a few days at the platform each year is a like a crash course on STB resistance. All subjects are covered and great experts around the world come together to discuss all details of this host-pathogen interaction,” said Filippo Bassi, senior durum wheat breeder at ICARDA.

“Sending young scientists to spend some time at the platform ensures that they learn all about the mechanisms of resistance and take them back to their home country to deploy them in their own breeding programs. It is like a true university for STB.”

Yet, the platform still has a lot of work to do, according to Ben M’Barek. Scientists at the platform are now working on raising awareness on crop and pest management such as integrated management approaches amongst farming communities, setting up on-farm field trials and developing disease early warning surveillance.

Next year the platform will provide a unique podium for students, academics and researchers to exchange ideas and research findings on cereal leaf blight diseases. The International Symposium on Cereal Leaf Blights will take place on May 19-21, 2021 in Tunisia. Details can be found here.

The Septoria Precision Phenotyping Platform is led by the International Maize and Wheat Improvement Center (CIMMYT), in collaboration with the Institution of Agricultural Research and Higher Education of Tunisia (IRESA) and the International Center for Agricultural Research in the Dry Areas (ICARDA) and is supported by the CGIAR Research Program in Wheat (WHEAT).

Septoria Precision Phenotyping Platform at Oued Béja (CRRGC). (Photo: Gert Kema/Wageningen University)

Agency unveils seed resistant to disease

For more than a decade, Maize Lethal Necrosis Disease (MLND) has ravaged crops causing farmers to incur huge losses and threatening food security.

Kenya Seed Company (KSC) researchers through partnerships have developed a superior maize variety that can withstand the disease.

Read more here:

https://www.standardmedia.co.ke/farmkenya/article/2001382769/agency-unveils-seed-resistant-to-disease

Battling devastating viral diseases, also in plants

When a maize lethal necrosis (MLN) outbreak happened in Kenya in 2011, scientists knew they needed to act fast. This viral disease, new to Kenya, was decimating maize fields. Within a few years, the viral disease spread rapidly in eastern Africa, through both insect vectors and contaminated seeds. If the virus were to spread into southern or West Africa, it would spell disaster for the smallholder farmers across the continent who depended on maize as a staple crop and for their family’s income and livelihoods.

The International Maize and Wheat Improvement Center (CIMMYT) and its partners immediately took action to impose a strict seed quarantine and restrict the movement of seed between eastern Africa and other regions in Africa. In addition, they worked intensively on developing and disseminating improved maize cultivars with tolerance or resistance to MLN, undertook extensive surveillance efforts, and sensitized partners on the importance of producing and commercializing MLN-free seed.

Due to these efforts, in the last nine years MLN has not been reported in sub-Saharan Africa outside of eastern Africa.

On the occasion of a recent publication on Virus Research about how MLN was contained, we interviewed B.M. Prasanna, director of the Global Maize Program at CIMMYT and the CGIAR Research Program on Maize (MAIZE), to discuss the MLN success story, the global COVID-19 crisis, and the similarities in the challenge to tackle plant and human viral diseases.

B.M. Prasanna, Director of the Global Maize Program at CIMMYT and the CGIAR Research Program on Maize (MAIZE). (Photo: Alfonso Cortés/CIMMYT)
B.M. Prasanna, Director of the Global Maize Program at CIMMYT and the CGIAR Research Program on Maize (MAIZE). (Photo: Alfonso Cortés/CIMMYT)

What were some of the extreme measures CIMMYT had to take to stop the spread of MLN?

The first step that we had to take in the fight against MLN was to rigorously analyze seed for any possible contamination with MLN-causing viruses and restrict movement of seed from eastern Africa to southern Africa.

The second most important step was to sensitize the national partners and the commercial seed sector about the danger of seed contamination with MLN-causing viruses, and how seed contamination can lead to the proliferation or spread of the disease.

The third important step was to build a new MLN quarantine facility in Zimbabwe, in partnership with the National Plant Quarantine Institute. Only when that quarantine facility was functional in 2017, we reinitiated transfer of research material from CIMMYT’s breeding hub in Kenya to CIMMYT in Zimbabwe. Only when the materials were certified to be MLN-free both in Kenya and Zimbabwe, through plant-by-plant analysis using immunodiagnostic kits, the seed was multiplied and further distributed to partners. So, the principle of containment and effective management is extremely important, whether it is a plant viral disease or a human viral disease.

We must note here that in terms of scale and intensity, as well as global effects and implications, any plant disease, including MLN, cannot be compared with a pandemic like COVID-19, which has affected every aspect of our lives.

Maize Lethal Necrosis (MLN) sensitive and resistant hybrid demo plots in Naivasha’s quarantine & screening facility (Photo: KIPENZ/CIMMYT)
Maize Lethal Necrosis (MLN) sensitive and resistant hybrid demo plots in Naivasha’s quarantine & screening facility (Photo: KIPENZ/CIMMYT)

How do you think the COVID-19 pandemic is going to impact our food systems?

We are indeed in a grim situation. The pandemic will undoubtedly have a serious effect on food security.

Many countries which do not have enough food reserves or those where the food systems are vulnerable to shocks like this are suffering. The people’s capacity to procure inputs for agriculture, including seed, is going to be affected too, as the markets are affected. This is really a serious situation that we all should be concerned about. The CGIAR has an important role to play, in terms of working closely with national partners and mitigating the impact of COVID-19 on agriculture.

We should be particularly worried about farmers, especially smallholder farmers, who are quite vulnerable to the ongoing challenge. Even without COVID-19, agriculture in many developing countries worldwide has been already under distress. Small and marginal farmers were often unable to find a market for their produce and earn sufficient income to support their families. Their livelihoods are fragile, and vulnerable to climate change and volatile market prices. The ongoing COVID-19 crisis is unfortunately compounding the crisis.

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)
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)

What lessons can agricultural research learn from this pandemic?

What do these pandemics or epidemics teach us? They remind us that systems need to be in place to prevent the proliferation of such diseases, whether it is plant diseases or animal diseases or human diseases. No country can be considered completely safe, and such diseases do not discriminate between a developed and a developing country, or the rich and the poor.

The second most important lesson is emergency preparedness. Whenever such devastating transboundary viral diseases show up, how quickly the country can respond — containing that infected area and not allowing the disease to spread, and then mitigating the damage systematically and quickly — is key. This is not the first time that a disease like MLN has emerged. There could be more serious viral or fungal diseases that could emerge in the future due to various reasons, including changing climates, international trade, movement of human beings, air currents, etc.  There are multiple ways that diseases can go across continents, across countries within a continent, and within countries. Therefore, the key is how well we can capacitate the national systems to be able to proactively prevent, detect, and intervene very fast.

Another big lesson here for agricultural systems is that a problem that happens in some other continent cannot be ignored because you work in a different continent. What COVID-19 shows is that the world is far more connected than we think.

CIMMYT team members check for traces of the maize chlorotic mottle virus (MCMV) in maize plants during a visit to the MLN screening facility in Naivasha, Kenya. (Photo: Joshua Masinde/CIMMYT)
CIMMYT team members check for traces of the maize chlorotic mottle virus (MCMV) in maize plants during a visit to the MLN screening facility in Naivasha, Kenya. (Photo: Joshua Masinde/CIMMYT)

For you, what is the biggest takeaway from the MLN success story?

I won’t say it is still a complete success. Through intensive partnerships and efforts, we were able to prevent the disease from devastating maize production in millions of smallholder farmers’ fields in sub-Saharan Africa. Since 2014, there has been no new country in Africa — outside eastern Africa — that has reported an outbreak of MLN. That, to me, is a tremendous success.

The work is still not over. The journey has to continue. And we still need to make sure that countries are continuously protected from devastating diseases like MLN. MLN is still not eradicated from eastern Africa. It may not be even possible to completely eradicate this disease, as the two viruses that together cause it can survive not just on maize but on multiple grasses. We can however contain the disease and limit its impact through continued efforts, like what we have done for the past 7 or 8 years. But if we lower our guard, there is a very high likelihood that the disease can still spread to other countries in sub-Saharan Africa, especially the major maize-growing countries in southern Africa or West Africa. Efforts need to continue. So, let us continue to maintain a high vigil to protect the smallholders in Africa from transboundary diseases like MLN.

Read the full article on Virus Research:
Maize lethal necrosis (MLN): Efforts toward containing the spread and impact of a devastating transboundary disease in sub-Saharan Africa

Blast and rust forecast

An early warning system set to deliver wheat disease predictions directly to farmers’ phones is being piloted in Bangladesh and Nepal by interdisciplinary researchers.

Experts in crop disease, meteorology and computer science are crunching data from multiple countries to formulate models that anticipate the spread of the wheat rust and blast diseases in order to warn farmers of likely outbreaks, providing time for pre-emptive measures, said Dave Hodson, a principal scientist with the International Maize and Wheat Improvement Center (CIMMYT) coordinating the pilot project.

Around 50,000 smallholder farmers are expected to receive improved disease warnings and appropriate management advisories through the one-year proof-of-concept project, as part of the UK Aid-funded Asia Regional Resilience to a Changing Climate (ARRCC) program.

Early action is critical to prevent crop diseases becoming endemic. The speed at which wind-dispersed fungal wheat diseases are spreading through Asia poses a constant threat to sustainable wheat production of the 130 million tons produced in the region each year.

“Wheat rust and blast are caused by fungal pathogens, and like many fungi, they spread from plant to plant — and field to field — in tiny particles called spores,” said Hodson. “Disease strain mutations can overcome resistant varieties, leaving farmers few choices but to rely on expensive and environmentally-damaging fungicides to prevent crop loss.”

“The early warning system combines climate data and epidemiology models to predict how spores will spread through the air and identifies environmental conditions where healthy crops are at risk of infection. This allows for more targeted and optimal use of fungicides.”

The system was first developed in Ethiopia. It uses weather information from the Met Office, the UK’s national meteorological service, along with field and mobile phone surveillance data and disease spread modeling from the University of Cambridge, to construct and deploy a near real-time early warning system.

CIMMYT consultant Madan Bhatta conducts field surveys using Open Data Kit (ODK) in the mid-hills of Nepal. (Photo: D. Hodson/CIMMYT)
CIMMYT consultant Madan Bhatta conducts field surveys using Open Data Kit (ODK) in the mid-hills of Nepal. (Photo: D. Hodson/CIMMYT)

Initial efforts focused on adapting the wheat stripe and stem rust model from Ethiopia to Bangladesh and Nepal have been successful, with field surveillance data appearing to align with the weather-driven disease early warnings, but further analysis is ongoing, said Hodson.

“In the current wheat season we are in the process of comparing our disease forecasting models with on-the-ground survey results in both countries,” the wheat expert said.

“Next season, after getting validation from national partners, we will pilot getting our predictions to farmers through text-based messaging systems.”

CIMMYT’s strong partnerships with governmental extension systems and farmer associations across South Asia are being utilized to develop efficient pathways to get disease predictions to farmers, said Tim Krupnik, a CIMMYT Senior Scientist based in Bangladesh.

“Partnerships are essential. Working with our colleagues, we can validate and test the deployment of model-derived advisories in real-world extension settings,” Krupnik said. “The forecasting and early warning systems are designed to reduce unnecessary fungicide use, advising it only in the case where outbreaks are expected.”

Local partners are also key for data collection to support and develop future epidemiological modelling, the development of advisory graphics and the dissemination of information, he explained.

The second stage of the project concerns the adaptation of the framework and protocols for wheat blast disease to improve existing wheat blast early warning systems already pioneered in Bangladesh.

Example of weekly stripe rust spore deposition forecast in Nepal. Darker colors represent higher predicted number of spores deposited. The early warning system combines weather information from the Met Office with field and mobile phone surveillance data and disease spread modeling from the University of Cambridge. (Graphic: University of Cambridge and Met Office)
Example of weekly stripe rust spore deposition forecast in Nepal. Darker colors represent higher predicted number of spores deposited. The early warning system combines weather information from the Met Office with field and mobile phone surveillance data and disease spread modeling from the University of Cambridge. (Graphic: University of Cambridge and Met Office)

Strong scientific partnership champions diversity to achieve common goals

The meteorological-driven wheat disease warning system is an example of effective international scientific partnership contributing to the UN Sustainable Development Goals, said Sarah Millington, a scientific manager at Atmospheric Dispersion and Air Quality Group with the Met Office.

“Diverse expertise from the Met Office, the University of Cambridge and CIMMYT shows how combined fundamental research in epidemiology and meteorology modelling with field-based disease observation can produce a system that boosts smallholder farmers’ resilience to major agricultural challenges,” she said.

The atmospheric dispersion modeling was originally developed in response to the Chernobyl disaster and since then has evolved to be able to model the dispersion and deposition of a range of particles and gases, including biological particles such as wheat rust spores.

“The framework together with the underpinning technologies are transferable to forecast fungal disease in other regions and can be readily adapted for other wind-dispersed pests and disease of major agricultural crops,” said Christopher Gilligan, head of the Epidemiology and Modelling Group at the University of Cambridge.

Fungal wheat diseases are an increasing threat to farmer livelihoods in Asia

Wheat leaf rust can be spotted on a wheat plant of a highly susceptible variety in Nepal. The symptoms of wheat rust are dusty, reddish-orange to reddish-brown fruiting bodies that appear on the leaf surface. These lesions produce numerous spores, which are spread by wind and splashing water. (Photo: D Hodson/CIMMYT)
Wheat leaf rust can be spotted on a wheat plant of a highly susceptible variety in Nepal. The symptoms of wheat rust are dusty, reddish-orange to reddish-brown fruiting bodies that appear on the leaf surface. These lesions produce numerous spores, which are spread by wind and splashing water. (Photo: D Hodson/CIMMYT)

While there has been a history of wheat rust disease epidemics in South Asia, new emerging strains and changes to climate pose an increased threat to farmers’ livelihoods. The pathogens that cause rust diseases are continually evolving and changing over time, making them difficult to control.

Stripe rust threatens farmers in Afghanistan, India, Nepal and Pakistan, typically in two out of five seasons, with an estimated 43 million hectares of wheat vulnerable. When weather conditions are conducive and susceptible cultivars are grown, farmers can experience losses exceeding 70%.

Populations of stem rust are building at alarming rates and previously unseen scales in neighboring regions. Stem rust spores can spread across regions on the wind; this also amplifies the threat of incursion into South Asia and the ARRCC program’s target countries, underscoring the very real risk that the disease could reemerge within the subcontinent.

The devastating wheat blast disease, originating in the Americas, suddenly appeared in Bangladesh in 2016, causing wheat crop losses as high as 30% on a large area, and continues to threaten South Asia’s vast wheat lands.

In both cases, quick international responses through CIMMYT, the CGIAR research program on Wheat (WHEAT) and the Borlaug Global Rust Initiative have been able to monitor and characterize the diseases and, especially, to develop and deploy resistant wheat varieties.

The UK aid-funded ARRCC program is led by the Met Office and the World Bank and aims to strengthen weather forecasting systems across Asia. The program is delivering new technologies and innovative approaches to help vulnerable communities use weather warnings and forecasts to better prepare for climate-related shocks.

The early warning system uses data gathered from the online Rust Tracker tool, with additional fieldwork support from the Cereal Systems Initiative for South Asia (CSISA), funded by USAID and the Bill & Melinda Gates Foundation, both coordinated by CIMMYT.