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Successful surveillance results in early first detection of Ug99 in South Asia

Successful global wheat disease surveillance and monitoring has resulted in early detection of wheat stem rust Ug99 in Nepal. A combination of vigilant field surveys and sampling by Nepal’s National Plant Pathology Research Centre (NPPRC) and National Wheat Research Program (NWRP), supported by rigorous and accurate disease diagnostics at the Global Rust Reference Center (GRRC), Denmark, resulted in confirmed detection of the Ug99 strain named TTKTT. The long running and sustained surveillance efforts undertaken by NPPRC and NWRP, including off-season surveys, proved vital in the detection of Ug99 in Nepal. Confirmed results were obtained from two field samples collected in early November 2023 from off-season summer wheat crops in Dolakha district, Nepal. Repeated experiments and high quality pathotyping and genotyping at GRRC confirmed the results.

“The combination of molecular genotyping of incoming samples, without prior recovery in our laboratory and independent diagnostic assays of recovered stem rust isolates, confirmed the presence of Ug99 and a highly virulent race variant termed TTKTT,” says professor Mogens Hovmøller, leader of the GRRC at Aarhus University in Denmark.

Suraj Baidya (NPPRC) and Roshan Basnet (National Wheat Research Program) undertake field surveys at Dandunghe, Dolakha, Nepal. (Photo: CIMMYT)

Ug99 was first detected in East Africa in 1998/99, and its unique virulence sparked fears that a large proportion of wheat cultivars globally would be at risk from this potentially devastating disease. The international wheat community came together through the Borlaug Global Rust Initiative (BGRI) to address the threats posed by Ug99. The BGRI partners have successfully monitored the evolution and spread of Ug99 and bred hundreds of resistant wheat varieties that are now being grown at scale in priority wheat growing regions. Migration of Ug99 from Africa to other regions, including South Asia, was always seen as likely due to the transboundary nature of the disease and long-distance dispersal of rust spores by wind.

Detection of a Ug99 race in Nepal is not therefore a surprise, but it highlights the effectiveness of the wheat rust surveillance and monitoring systems that have been developed. The disease was present at extremely low levels in the fields in Nepal, and early detection is one of the main factors in preventing disease spread. Other factors also contribute to reduced risk. The wheat on which the Ug99 race TTKTT was detected were fodder crops and cut soon after the surveys were completed, which prevented further buildup of disease. In addition, no wheat is grown in the main season in these areas, with farmers shifting to cultivation of potato (a non-host crop for stem rust).

According to Suraj Baidya, senior scientist and chief of NPPRC, “Extensive follow up surveys in the Dolakha detection area by NPPRC in the 2023/24 main season resulted in no wheat being observed and no detection of stem rust.” Similarly, extensive surveys by NPPRC throughout other wheat growing areas of Nepal in the 2023/24 main season have resulted in no reports of stem rust in the country. To date, extensive surveys in other countries in South Asia (Pakistan, Bangladesh, Bhutan) have not detected stem rust in 2023/24.

Although the current risk of stem rust outbreaks is considered to be low, detection of the Ug99 race TTKTT in Nepal is a clear reminder of the threat posed to wheat production in South Asia by the incursion of virulent stem rust races or other plant diseases of concern. “The spread and risk from transboundary diseases like stem rust is increasing,” says Dave Hodson, leader of the Wheat Disease Early Warning Advisory Systems (DEWAS) project at CIMMYT. “Sustained and increased surveillance efforts are needed across the region and expanded to include other important emerging diseases.” Successful deployment of Ug99 resistant cultivars through the BGRI partners, including CIMMYT, ICARDA and NARS, has decreased vulnerability, but it is important to note that the race TTKTT is a recently evolved variant of Ug99 with additional virulence compared to the original strains. As a result, not all cultivars in South Asia may have effective resistance today. Screening of germplasm and major cultivars from South Asia against TTKTT at the Kenya Agriculture and Livestock Research Organization (KALRO)/CIMMYT international stem rust screening nursery in Kenya is extremely important to get an accurate picture of current vulnerability.

The details of the diagnostic confirmation of Ug99 in Nepal are available at the GRRC website (see GRRC lab report)

Work on wheat disease surveillance and monitoring, plus breeding of resistant varieties is being supported by the DEWAS and AGG projects funded by BMGF and FCDO, UK.

Key partners –

National Plant Pathology Research Centre (NPPRC), Nepal. Contact: Suraj Baidya (suraj_baidya222@yahoo.co.in)

National Wheat Research Program (NWRP), Nepal. Contact: Roshan Basnet

Global Rust Reference Center (GRRC), Aarhus University, Denmark. Contact: Mogens Hovmøller (mogens.hovmoller@agro.au.dk)

Cornell University. Contact: Maricelis Acevedo (ma934@cornell.edu)

CIMMYT. Contact: David Hodson (d.hodson@cgiar.org)

Bargaining for Better: How gender roles in household decision-making can impact crop disease resilience

‘A better understanding of the links between gender roles in household decision-making and the adoption of technologies can enhance the uptake of innovations in smallholder farming systems,’ concludes a recently published paper by CIMMYT. The paper connects women’s bargaining power in households with the adoption of rust resistant wheat varieties, based on the work of Accelerating Genetic Gains in Maize and Wheat (AGG) in Ethiopia.

“While an emerging body of literature finds positive correlations between women’s influence in household decision-making and socioeconomic, health, and nutritional outcomes, few studies have analyzed the links between intra-household decision-making and the adoption of agricultural technologies,” said Michael Euler, agriculture research economist at CIMMYT.

A case study in Ethiopia

For this study, researchers used a dataset from Ethiopian wheat-producing households.

Ethiopia is the second-largest wheat producer in Africa, with an aggregate grain production of 5.5 million metric tons and 4-5 million farmers engaged in cultivation. The Ethiopian Highlands are a hot spot for wheat rust. With recurrent epidemics in the last decade, the emergence of new strains of wheat rust increased production risks. On the positive side, farmers seem to be responsive to the management of rust diseases. Rust-resistant bread wheat varieties, released since 2010, have been widely adopted by smallholder farmers across Ethiopia.

The CIMMYT study surveyed 1,088 wheat-producing households in Ethiopia to analyze the links between women’s role in household decision-making concerning crop production and the adoption and turnover rates of rust-resistant wheat varieties. Female and male members from the same households responded separately, which facilitated capturing individual perceptions and the intra-household dynamics in decision-making.

Farmer Shumuna Bedeso weeds her wheat field. (Photo: Peter Lowe/CIMMYT)

Intra-household decision-making arrangements and wheat varietal choice

Overall, the study reveals a positive association between women’s role in decision-making regarding the selection of wheat seed and the adoption of rust-resistant wheat varieties and wheat varietal turnover. Findings may be related to differences in risk aversion between women and men farmers. While women farmers may tend to advocate for the adoption of rust resistant varieties to avoid potential financial difficulties that arise from purchase of fungicide in the growing season, men farmers may be more inclined to adopt high yielding varieties and use fungicides to combat rust within the season.

Spouses may agree or have different opinions regarding their decision-making roles. Spousal agreement on the woman having a role in making crop variety decisions is associated with higher adoption rates compared to spousal agreement that the woman has no role. Joint decision-making with mutually uncontested spousal roles may yield better outcomes due to larger combined exposure to information, as well as spousal discussion and reflection on potential implications of the varietal choice decision.

Conclusion: It is about negotiation, contestation and consensus

Household decisions, including the decision to adopt agricultural technologies often result from negotiation, contestation, and consensus between wife and husband. This process is shaped by diverging interests, motivations and objectives, while its results are determined by different levels of individual bargaining power. “Our findings indicate that women’s ownership of agricultural land and household assets is strongly associated with their active role in household decisions on wheat varietal choice, and with spousal agreement,” said Moti Jaleta, senior agricultural economist at CIMMYT. The dynamics in intra-household decision-making are likely to influence households’ adoption of agricultural technologies.

Disregarding the dynamics in decision-making implies that households are unilateral decision-makers, a scenario which probably does not hold true considering the level of spousal disagreement regarding their roles and influence in choosing crop varieties. A deeper understanding of the connections between gender dynamics in household decision-making and adoption choices can enhance the efficiency of public extension systems, increase the adoption rates of modern innovations, improve agricultural productivity, and enhance livelihoods in smallholder agriculture.

Read the complete paper here.

Scientists convene in Kenya for intensive wheat disease training

An international cohort of scientists representing 12 countries gathered at the Kenya Agricultural and Livestock Research Organization (KALRO) station in Njoro for a comprehensive training course aimed at honing their expertise in wheat rust pathology.

The two-week program “Enhancing Wheat Disease Early Warning Systems, Germplasm Evaluation, Selection, and Tools for Improving Wheat Breeding Pipelines,” was a collaborative effort between CIMMYT and Cornell University and supported by the Wheat Disease Early Warning Advisory System (DEWAS) and Accelerating Genetic Gains in Maize and Wheat projects.

With a mission to bolster the capabilities of National Agricultural Research Systems (NARS), the training course attracted more than 30 participants from diverse corners of the globe.

Maricelis Acevedo, a research professor of global development at Cornell and the associate director of Wheat DEWAS, underscored the initiative’s significance. “This is all about training a new generation of scientists to be at the forefront of efforts to prevent wheat pathogens epidemics and increase food security all over the globe,” Acevedo said.

First initiated in 2008 through the Borlaug Global Rust Initiative, these training programs in Kenya have played a vital role in equipping scientists worldwide with the most up-to-date knowledge on rust pathogens. The initial twelve training sessions received support from the BGRI under the auspices of the Durable Rust Resistance in Wheat and Delivering Genetic Gain in Wheat projects.

This year’s training aims to prepare global scientists to protect against disease outbreaks that threaten wheat productivity in East Africa and South Asia. The course encompassed a wide array of practical exercises and theoretical sessions designed to enhance the participants’ knowledge in pathogen surveillance, diagnostics, modeling, data management, early warning assessments, and open science publishing. Presentations were made by DEWAS partners from the John Innes Centre, Aarhus University, the University of Cambridge and University of Minnesota.

(Photo: Borlaug Global Rust Initiative)

The course provided practical, hands-on experience in selecting and evaluating wheat breeding germplasm, race analysis and greenhouse screening experiments to enhance knowledge of rust diseases, according to Sridhar Bhavani, training coordinator for the course.

“This comprehensive training program encompasses diverse aspects of wheat research, including disease monitoring, data management, epidemiological models, and rapid diagnostics to establish a scalable and sustainable early warning system for critical wheat diseases such as rusts, fusarium, and wheat blast,” said Bhavani, wheat improvement lead for East Africa at CIMMYT and head of wheat rust pathology and molecular genetic in CIMMYT’s Global Wheat program.

An integral part of the program, Acevedo said, was the hands-on training on wheat pathogen survey and sample collection at KALRO.  The scientists utilized the international wheat screening facility at KALRO as a training ground for hot-spot screening for rust diseases resistance.

Daisy Kwamboka, an associate researcher at PlantVillage in Kenya, said the program provided younger scientists with essential knowledge and mentoring.

“I found the practical sessions particularly fascinating, and I can now confidently perform inoculations and rust scoring on my own,” said Kwamboka said, who added that she also learned how to organize experimental designs and the basics of R language for data analysis.

DEWAS research leaders Dave Hodson, Bhavani and Acevedo conducted workshops and presentations along with leading wheat rust experts. Presenters included Robert Park and Davinder Singh from the University of Sydney; Diane Sauders from the John Innes Centre; Clay Sneller from Ohio State University; Pablo Olivera from the University of Minnesota; Cyrus Kimani, Zennah Kosgey and Godwin Macharia from KALRO; Leo Crespo, Susanne Dreisigacker, Keith Gardner, Velu Govindan, Itria Ibba, Arun Joshi, Naeela Qureshi, Pawan Kumar Singh and Paolo Vitale from CIMMYT; Chris Gilligan and Jake Smith from the University of Cambridge; and Jens Grønbech Hansen and Mogens S. Hovmøller from the Global Rust Reference Center at Aarhus University.

“I thoroughly enjoyed the knowledge imparted by the invited experts, along with the incredible care they have shown us throughout this wonderful training.”

Narain Dhar, Borlaug Institute for South Asia 

For participants, the course offered a crucial platform for international collaboration, a strong commitment to knowledge sharing, and its significant contribution to global food security.

“The dedication of the trainers truly brought the training to life, making it incredibly understandable,” said Narain Dhar, research fellow at the Borlaug Institute for South Asia.

The event not only facilitated learning but also fostered connections among scientists from different parts of the world. These newfound connections hold the promise of sparking innovative collaborations and research endeavors that could further advance the field of wheat pathology.

Wheat pathogen surveillance system set to expand through new investment

One of the world’s largest crop pathogen surveillance systems is set to expand its analytic and knowledge systems capacity to protect wheat productivity in food vulnerable areas of East Africa and South Asia.

Researchers announced the Wheat Disease Early Warning Advisory System (Wheat DEWAS), funded through a $7.3 million grant from the Bill & Melinda Gates Foundation and the United Kingdom’s Foreign, Commonwealth & Development Office, to enhance crop resilience to wheat diseases.

The project is led by David Hodson, principal scientist at CIMMYT, and Maricelis Acevedo, research professor of global development and plant pathology at Cornell University’s College of Agriculture and Life Sciences. This initiative brings together research expertise from 23 research and academic organizations from sub-Saharan Africa, South Asia, Europe, the United States and Mexico.

Wheat DEWAS aims to be an open and scalable system capable of tracking important pathogen strains. The system builds on existing capabilities developed by the research team to provide near-real-time model-based risk forecasts and resulting in accurate, timely and actionable advice to farmers. As plant pathogens continue to evolve and threaten global food production, the system strengthens the capacity of countries to respond in a proactive manner to transboundary wheat diseases.

The system focuses on the two major fungal pathogens of wheat known as rust and blast diseases. Rust diseases, named for a rust-like appearance on infected plants, are hyper-variable and can significantly reduce crop yields when they attack. The fungus releases trillions of spores that can ride wind currents across national borders and continents and spread devastating epidemics quickly over vast areas.

Wheat blast, caused by the fungus Magnaporte oryzae Tritici, is an increasing threat to wheat production, following detection in both Bangladesh and Zambia. The fungus spreads over short distances and through the planting of infected seeds. Grains of infected plants shrivel within a week of first symptoms, providing little time for farmers to take preventative actions. Most wheat grown in the world has limited resistance to wheat blast.

“New wheat pathogen variants are constantly evolving and are spreading rapidly on a global scale,” said Hodson, principal investigator for Wheat DEWAS. “Complete crop losses in some of the most food vulnerable areas of the world are possible under favorable epidemiological conditions. Vigilance coupled with pathogen-informed breeding strategies are essential to prevent wheat disease epidemics. Improved monitoring, early warning and advisory approaches are an important component for safeguarding food supplies.”

Previous long-term investments in rust pathogen surveillance, modelling, and diagnostics built one of the largest operational global surveillance and monitoring system for any crop disease. The research permitted the development of functioning prototypes of advanced early warning advisory systems (EWAS) in East Africa and South Asia. Wheat DEWAS seeks to improve on that foundation to build a scalable, integrated, and sustainable solution that can provide improved advanced timely warning of vulnerability to emerging and migrating wheat diseases.

“The impact of these diseases is greatest on small-scale producers, negatively affecting livelihoods, income, and food security,” Acevedo said. “Ultimately, with this project we aim to maximize opportunities for smallholder farmers to benefit from hyper-local analytic and knowledge systems to protect wheat productivity.”

The system has already proven successful, contributing to prevention of a potential rust outbreak in Ethiopia in 2021. At that time, the early warning and global monitoring detected a new yellow rust strain with high epidemic potential. Risk mapping and real-time early forecasting identified the risk and allowed a timely and effective response by farmers and officials. That growing season ended up being a production record-breaker for Ethiopian wheat farmers.

While wheat is the major focus of the system, pathogens with similar biology and dispersal modes exist for all major crops. Discoveries made in the wheat system could provide essential infrastructure, methods for data collection and analysis to aid interventions that will be relevant to other crops.

Is uptake of rust-resistant wheat linked to gender equality?

Sieg Snapp presents research on agroecological approaches to maize farming in Malawi and Zimbabwe at Tropentag 2022. (Photo: Ramiro Ortega Landa/CIMMYT)

Farmers, development practitioners and scientists gathered at Tropentag 2022 between September 14-16 to answer a question that will affect all our futures: can agroecological farming feed the world?

Tropentag is an annual interdisciplinary conference on research in tropical and subtropical agriculture, natural resource management and rural development, jointly organized by nine European universities and the Council for Tropical and Subtropical Agricultural Research (ATSAF e.V), in cooperation with the GIZ Fund International Agricultural Research (FIA).

This year’s event explored the potential of agroecology to contribute to improved nutrition, enhanced natural resource management and farm incomes.

Sieg Snapp, Director of the Sustainable Agrifood Systems (SAS) program at the International Maize and Wheat Improvement Center (CIMMYT) presented on agroecology approaches to enhance learning in a changing world based on experiences with maize-based cropping systems in southern Africa. Snapp suggested that accelerated learning and adaptative capacity are key to the local generation of suitable solutions to agricultural problems, and proposed agroecology as a foundational approach that emphasizes understanding principles, harnessing biological processes, and enhancing local capacity.

Snapp shared how an agroecology living laboratory in Malawi has supported farmer agency around soil health, crop diversification and sustainable intensification since 2013, while living labs are being established in “food territories” in Zimbabwe to support innovation and strategies for evaluating the benefits of farm-scale agroecology approaches. She also explored solutions for pest management, inclusive financing modalities and collaborative innovation generation between farmers and researchers.

Gender and disease-resistant varieties

Michael Euler, Agricultural Resource Economist at CIMMYT, presented in the conference session on technology adoption and dissemination for smallholder farms, which included contributions on the adoption and impact of improved forage production, use of biogas facilities, agroecological management practices, improved wheat seeds, and access to and use genetic diversity in gene banks.

Based on data from CIMMYT’s Accelerating Genetic Gains in Maize and Wheat (AGG) project in Ethiopia, Euler presented a study on how intra-household decision-making dynamics influence the adoption of rust-resistant wheat varieties.

By using questionnaires that were addressed separately to male and female spouses in the household, researchers obtained insights on perceived individual roles in decision-making and agreements. The study found that an increase in the role of the female spouse in household farming decisions is positively associated with the uptake of rust-resistant varieties.

Additional sessions from the event focused on crops and cropping systems, animal production systems, food security and nutrition, agroecology, and food processing and quality.

Singh recognized for wheat crop improvement

Ravi Singh delivers a lecture during the 61st All India Wheat and Barley Research Workers’ Meet celebrating the fruitful partnership of CIMMYT and ICAR. (Credit: SAWBAR)

Ravi Singh, head of wheat improvement and rust research at the International Maize and Wheat Improvement Center (CIMMYT), received the Sh. VS Mathur Memorial Award 2022 for outstanding contribution in the field of wheat crop improvement from the Society for Advancement of Wheat and Barley Research (SAWBAR).

Singh received the award from T. R. Sharma, Deputy Director General of the Indian Council of Agricultural Research (ICAR) and G. P. Singh, Director of the Indian Institute for Wheat and Barley Research (IIWBR) at ICAR.

As recipient of the award, Singh delivered a lecture during the 61st All India Wheat and Barley Research Workers’ Meet in Gwalior, India, on August 29. He highlighted and praised the partnership between India and CIMMYT as essential for accelerating gains in wheat yield despite the stresses of climate change thanks to improved resilience in new varieties and earlier sowing.

“The ICAR-CIMMYT wheat improvement partnership remains crucial for delivering new varieties with higher rates of genetic gain in farmers’ fields to enhance productivity, climate resilience, disease resistance and nutrition while meeting market needs,” he said.

Successes of the partnership include integrated breeding with a common agenda, commercialized varieties that are adapted to flexible sowing dates including early sowing, diverse and durable resistance to rust diseases, adoption of wheat blast resistant varieties in large areas, biofortified and high-quality varieties, and the move towards mainstreaming of zinc (Zn) biofortification.

Singh also paid homage to the award’s namesake, as VS Mathur’s “wheat varieties once occupied fields of many millions of farmers and provided food and nutrition to many more millions throughout India and beyond”.

Singh, a CIMMYT scientist, receives the Sh. VS Mathur Memorial Award for his outstanding contribution in the field of wheat crop improvement. (Credit: SAWBAR)

About SAWBAR:

SAWBAR was founded in 2007 and is housed at ICAR-Indian Institute of Wheat and Barley Research Karnal (Haryana) India. The Society presently has 300 life members and more than 320 annual and student members. SAWBAR is playing a significant role in bringing wheat and barley researchers on one platform for the exchange of innovative research and dissemination of knowledge related to the latest research happenings in the area of wheat and barley improvement. Annually, SAWBAR gives awards to pioneer cereal workers in various award categories. 

About the Sh. VS Mathur Mathur Memorial Award:

The Sh. VS Mathur Memorial Award was constituted in year 2018 in the memory of eminent wheat worker Sh. VS Mathur. Mathur was one of the pioneer wheat workers who worked tirelessly with MS Swaminathan and HK Jain and developed a large number of high-yielding wheat varieties viz. Heera, Moti, Janak (HD 1982), Arjun (HD 2009), HD 2177, HD 2182, HD 2204, HD 2236, HD 2278, HD 2281, HD 2285, HD 2329, HD 2307 and HD 2327 for various regions of India.

MARPLE reaches South Asia

Workshop participants stand for a group photo. (Photo: Danny Ward/John Innes Centre)
Workshop participants stand for a group photo. (Photo: Danny Ward/John Innes Centre)

On April 26–29, 2022, researchers from Nepal participated in a workshop on the use of MARPLE Diagnostics, the most advanced genetic testing methodology for strain-level diagnostics of the deadly wheat yellow rust fungus. Scientists from the International Maize and Wheat Improvement Center (CIMMYT) and the John Innes Centre trained 21 researchers from the Nepal Agricultural Research Council (NARC) and one from iDE. The workshop took place at NARC’s National Plant Pathology Research Centre in Khumaltar, outside the capital Kathmandu.

“The need for new diagnostic technologies like MARPLE and the critical timing of the workshop was highlighted by the severe yellow rust outbreak observed this season in the western areas of Nepal,” commented Dave Hodson, Senior Scientist at CIMMYT and project co-lead. “Having national capacity to detect the increasing threats from yellow rust using MARPLE will be an important tool to help combat wheat rusts in Nepal”.

The yellow rust fungus can cause grain yield losses of 30–80 % to wheat, Nepal’s third most important food crop.

Current diagnostic methods for wheat rust used in Nepal are slow, typically taking months between collecting the sample and final strain identification. They are also costly and reliant on sending samples overseas to highly specialized labs for analysis.

MARPLE (Mobile and Real-time PLant disEase) Diagnostics is the first method to place strain-level genetic diagnostics capability directly into the hands of Nepali researchers, generating data in-country in near-real time, for immediate integration into early warning systems and disease management decisions.

“This is a fantastic opportunity to bring the latest innovations in plant disease diagnostics for the wheat rust pathogens to where they are needed most, in the hands of researchers in the field working tirelessly to combat these devastating diseases,” commented Diane Saunders, Group Leader at the John Innes Centre and project co-lead.

Diane Saunders (left), Group Leader at the John Innes Centre and project co-lead, observes workshop participants during the use of MARPLE. (Photo: Danny Ward/John Innes Centre)
Diane Saunders (left), Group Leader at the John Innes Centre and project co-lead, observes workshop participants during the use of MARPLE. (Photo: Danny Ward/John Innes Centre)

Suraj Baidya senior scientist and chief of the National Plant Pathology Research Centre at NARC noted the worrying recent geographical expansion of yellow rust in Nepal. “Due to global warming, yellow rust has now moved into the plain and river basin area likely due to evolution of heat tolerant pathotypes. MARPLE Diagnostics now gives us the rapid diagnostics needed to help identify and manage these changes in the rust pathogen population diversity,” he said.

The highly innovative MARPLE Diagnostics approach uses the hand-held MinION nanopore sequencer, built by Oxford Nanopore, to generate genetic data to type strains of the yellow rust fungus directly from field samples.

Beyond MARPLE Diagnostics, Saunders noted that “the workshop has also opened up exciting new possibilities for researchers in Nepal, by providing local genome-sequencing capacity that is currently absent.”

MARPLE (Mobile and Real-time PLant disEase) Diagnostics is a revolutionary mobile lab kit. It uses nanopore sequence technology to rapidly diagnose and monitor wheat rust in farmers’ fields. (Photo: Danny Ward/John Innes Centre)
MARPLE (Mobile and Real-time PLant disEase) Diagnostics is a revolutionary mobile lab kit. It uses nanopore sequence technology to rapidly diagnose and monitor wheat rust in farmers’ fields. (Photo: Danny Ward/John Innes Centre)

What’s next for MARPLE Diagnostics in Nepal?

Following the successful workshop, Nepali researchers will be supported by CIMMYT and the John Innes Centre to undertake MARPLE Diagnostics on field samples collected by NARC. “The current plan includes monitoring of yellow rust on the summer wheat crop planted at high hill areas and then early sampling in the 2022/23 wheat season,” Hodson noted.

“We were struck by the enthusiasm and dedication of our colleagues to embrace the potential offered by MARPLE Diagnostics. Looking forward, we are excited to continue working with our Nepali colleagues towards our united goal of embedding this methodology in their national surveillance program for wheat rusts,” Saunders remarked.

MARPLE Diagnostics is supported by the Feed the Future Innovation Lab for Current and Emerging Threats to Crops, funded by the United States Agency for International Development (USAID), the UK Biotechnology and Biological Sciences Research Council (BBSRC) Innovator of the Year Award, the CGIAR Big Data Platform Inspire Challenge, the Bill & Melinda Gates Foundation and the United Kingdom’s Foreign, Commonwealth and Development Office.

This article was originally published on the JIC website.

Singh receives lifetime award for wheat breeding successes

Ravi Singh, head of global wheat improvement at the International Maize and Wheat Improvement Center (CIMMYT), received the 2021 Borlaug Global Rust Initiative (BGRI) Lifetime Achievement Award for his contribution to protecting wheat from new races of some of agriculture’s oldest and most devastating diseases.

Read more: https://www.world-grain.com/articles/16099-singh-receives-lifetime-award-for-wheat-breeding-successes

CIMMYT, AGG wheat experts share latest discoveries at BGRI Technical Workshop

Dave Hodson, International Maize and Wheat Improvement Center (CIMMYT) senior scientist delivered a large-scale overview of the current global wheat rust situation and the state of disease surveillance systems. He underscored the importance of comprehensive early warning systems and promising new detection tools that help to raise awareness and improve control. A new assessment of the early warning system for rust In Ethiopia showed a real impact on farmers’ interest, awareness, and farming practices to control the disease, as well as high-level policy changes.

Alison Bentley, CIMMYT Global Wheat Program director, described cutting-edge tools and methods by CIMMYT and, in particular, the Accelerating Genetic Gains in Maize and Wheat for Improved Livelihoods (AGG) project to increase wheat productivity in the face of changing climates. In addition to the new approaches on the supply side, she argued, we also need increased research on the demand side to better understand why farmers will choose a new variety, the role of markets and gender, and how we can scale up these systems. Bentley emphasized the criticality of supporting public and private sector efforts to get more improved germplasm into farmers’ fields in less time.

Philomin Juliana, CIMMYT Global Wheat Program associate scientist highlighted the pivotal role that data plays in breeding decisions and line advancements in CIMMYT’s wheat breeding program. This has been facilitated by improvements in how data sets, like genomic estimated breeding values (GEBVs), are shared with breeders. “CIMMYT has adopted a holistic, data-driven selection approach” that leverages phenotypic data, genomic-estimated breeding values (GEBVs) and selection indices, Juliana explained.

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.

Aussie drives global research that underpins Australian wheat industry

Can you help shape the future of plant disease detection?

Artificial Intelligence (AI) and Machine Learning (ML) are increasingly being applied across a diverse range of disciplines. Many aspects of our lives and work are now benefiting from these technologies. Disease recognition, for both human and plant health, is no exception. Ever more powerful AI/ML techniques are now opening up exciting opportunities to improve surveillance, monitoring and early warning for disease threats.

Scientists from Penn State University/PlantVillage, working with CGIAR centers, FAO and national country partners, are at the forefront of AI/ML technology development applied to crop pest and disease recognition. Development of the “PlantVillage Nuru” mobile app has provided an accurate and simple automated disease diagnostic tool that can be used by non-experts, including farmers. A recent paper published in Frontiers of Plant Science demonstrated that Nuru could diagnose symptoms of cassava diseases at higher accuracy than agricultural extension agents or farmers.

“The value of tools like PlantVillage Nuru is that we can greatly increase the coverage and speed of surveillance,” says CIMMYT scientist and disease surveillance expert Dave Hodson. “Trained pathologists can only visit a limited number of fields at fixed times in the season. With tools like Nuru, extension agents and farmers can all contribute to field surveys. This can result in much faster detection of disease outbreaks, better early warning and improved chances of control”.

New advances in AI/ML technology are now promising even greater improvements in these already powerful tools. CIMMYT scientists have had a long-standing partnership with the PlantVillage group, working to try and develop improved diagnostics for important wheat diseases such as rusts and blast. Considerable progress in developing automated diagnostics for wheat diseases has already been made, but the introduction of advanced image segmentation and tiling techniques promises to be a major leap forward.

“Advances in computer science are constantly happening and this can benefit the mission of CGIAR and PlantVillage,” explains David Hughes, Dorothy Foehr Huck and J. Lloyd Huck Chair in Global Food Security at Penn State and founder of PlantVillage.

“Image segmentation and tiling techniques are a great example. They used to require intensive computing requirements. Now due to advances in computer science these powerful techniques are becoming more accessible and can be applied to plant disease problems like wheat rusts.”

By using these image segmentation and tiling techniques the developers at PlantVillage are now seeing a major improvement in the ability to automatically and accurately detect wheat rusts from in situ photos. “We could not identify rusts with the older approaches but this segmentation and tiling tool is a game changer. The computer goes pixel by pixel across the images which is well suited to diseases like rusts that can be spread across the leaf or stem of the plant. The computer now has a much more powerful search algorithm.”

The team led by Pete McCloskey, lead A.I. engineer at Plant Village, actually used a multi-step process. First they removed the background to help the machine focus in on the leaf. They then digitally chopped the leaf into segments giving the AI a further helping hand so it can focus in and find the rust. Then the whole leaf is stitched together and the rust is highlighted to help humans working in the PlantVillage cloud system.

Fig: Examples of manual, hand labelled images (top rows) compared to AI generated images using segmentation and tiling (bottom rows) for stem rust (upper image panel) and stripe rust (lower image panel).

This exciting new development in rapid, accurate field detection of wheat rusts now needs validation and improvement. As with all AI/ML applications, numbers of images included in the models really improve the quality of the final predictions. “The success of any machine learning model is rooted in the quality and quantity of the data it is trained on,” notes McCloskey. “Therefore, it is critical to source vast and diverse amounts of high-quality images from around the world in order to develop a global wheat rust recognition system.” In this aspect we hope that the CIMMYT global wheat community can help drive the development of these exciting new tools forward.

CIMMYT and PlantVillage are hoping to expand the current wheat rust image dataset and as a result produce an even more valuable, public good, disease detection tool. Given the extensive field work undertaken in wheat fields around the world by CIMMYT staff and partners, we hope that you can help us. Any photos of wheat rusts (stem, stripe and leaf rust) in the field would be valuable.

We would like to have images with one infected leaf or stem per image, it should be vertical in the image so you can see the whole leaf or stem segment. The leaf or stem needs to be in focus and should be roughly centered in the image. It helps to hold the tip of the leaf away from the stem, so it is outstretched and flat. Ideally for training data, the leaf should have only one type of rust and no other disease symptoms. It is okay to have other leaves/stems/soil/sky in the background. It is also okay to have hands and other body parts in the image.

Below are some example images. Any images can be uploaded here.

Sample images show a variety of wheat rusts (stem, stripe and leaf rust) in the field. (Photos: CIMMYT)

For more information contact Dave Hodson, CIMMYT (d.hodson@cgiar.org) or Pete McCloskey, PlantVillage (petermccloskey1@gmail.com). 

Adult plant resistance (APR): the strategy to beat persistent pathogens

Scientists examine Ug99 stem rust symptoms on wheat. (Photo: Petr Kosina/CIMMYT)

The three rust diseases, yellow (stripe) rust, black (stem) rust, and brown (left) rust occur in most wheat production environments, causing substantial yield losses and under serious epidemics, can threaten the global wheat supply.

CIMMYT is one of the largest providers of elite germplasm to national partners in over 80 countries. CIMMYT nurseries, known for research in developing adaptive, high-yielding and high-quality germplasm, also carry resistance to several biotic and abiotic stresses, such as rust disease.

Through years of research and experience, CIMMYT has found that durable control of wheat rusts can be achieved by developing and deploying wheat varieties with complex adult-plant resistance (APR). A combination of both conventional and modern technologies in APR will enable breeders to address the problem of rusts and other diseases and continue progress in delivering higher genetic gains, a key goal of the Accelerating Genetic Gains in Maize and Wheat (AGG) project.

Learn more about CIMMYT’s APR strategy: CIMMYT Strategy for Adult Plant Resistance (APR)

For more information on CIMMYT’s APR strategy, contact CIMMYT’s Head of Wheat Rust Pathology and Molecular Genetics, Sridhar Bhavani.

The global network safeguarding the world’s wheat

The new interactive map allows visitors to visually explore the milestones that allowed a global network of researchers to fight threats to wheat production.
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 world’s attention to the outbreak of a new variant of stem rust, Ug99, that threatened to wipe out 80% of the world’s 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 world’s wheat from disease and climate change. The map highlights the BGRI’s 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 world’s 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 world’s 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.

Browse the interactive story map:
Inside the Global Network Safeguarding the World’s Wheat from Disease and Climate Change

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 — two of the world’s 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 farmers’ specific needs. 

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.

 

Rust-resistant bread wheat varieties widely adopted in Ethiopia

Wheat fields in the Arsi highlands, Ethiopia, 2015. (Photo: CIMMYT/ Peter Lowe)
Wheat fields in the Arsi highlands, Ethiopia, 2015. (Photo: CIMMYT/ Peter Lowe)

A state-of-the-art study of plant DNA provides strong evidence that farmers in Ethiopia have widely adopted new, improved rust-resistant bread wheat varieties since 2014.

The results — published in Nature Scientific Reports — show that nearly half (47%) of the 4,000 plots sampled were growing varieties 10 years old or younger, and the majority (61%) of these were released after 2005.

Four of the top varieties sown were recently-released rust-resistant varieties developed through the breeding programs of the Ethiopian Institute for Agricultural Research (EIAR) and the International Maize and Wheat Improvement Center (CIMMYT).

Adoption studies provide a fundamental measure of the success and effectiveness of agricultural research and investment. However, obtaining accurate information on the diffusion of crop varieties remains a challenging endeavor.

DNA fingerprinting enables researchers to identify the variety present in samples or plots, based on a comprehensive reference library of the genotypes of known varieties. In Ethiopia, over 94% of plots could be matched with known varieties. This provides data that is vastly more accurate than traditional farmer-recall surveys.

This is the first nationally representative, large-scale wheat DNA fingerprinting study undertaken in Ethiopia. CIMMYT scientists led the study in partnership with EIAR, the Ethiopian Central Statistical Agency (CSA) and Diversity Array Technologies (DArT).

“When we compared DNA fingerprinting results with the results from a survey of farmers’ memory of the same plots, we saw that only 28% of farmers correctly named wheat varieties grown,” explained Dave Hodson, a principal scientist at CIMMYT and lead author of the study.

The resulting data helps national breeding programs adjust their seed production to meet demand, and national extension agents focus on areas that need better access to seed. It also helps scientists, policymakers, donors and organizations such as CIMMYT track their impact and prioritize funding, support, and the direction of future research.

“These results validate years of international investment and national policies that have worked to promote, distribute and fast-track the release of wheat varieties with the traits that farmers have asked for — particularly resistance to crop-destroying wheat rust disease,” said Hodson.

Ethiopia is the largest wheat producer in sub-Saharan Africa. The Ethiopian government recently announced its goal to become self-sufficient in wheat, and increasing domestic wheat production is a national priority.

Widespread adoption of these improved varieties, demonstrated by DNA fingerprinting, has clearly had a positive impact on both economic returns and national wheat production gains. Initial estimates show that farmers gained an additional 225,500 tons of production — valued at $50 million — by using varieties released after 2005.

The study results validate investments in wheat improvement made by international donor agencies, notably the Bill & Melinda Gates Foundation, the Ethiopian government, the UK Foreign, Commonwealth and Development Office (FCDO, formerly DFID), the US Agency for International Development (USAID) and the World Bank. Their success in speeding up variety release and seed multiplication in Ethiopia is considered a model for other countries.

“This is good news for Ethiopian farmers, who are seeing better incomes from higher yielding, disease-resistant wheat, and for the Ethiopian government, which has put a high national priority on increasing domestic wheat production and reducing dependence on imports,” said EIAR Deputy Director General Chilot Yirga.

The study also confirmed CGIAR’s substantial contribution to national breeding efforts, with 90% of the area sampled containing varieties released by Ethiopian wheat breeding programs and derived from CIMMYT and the International Center for Agricultural Research in the Dry Areas (ICARDA) germplasm. Varieties developed using germplasm received from CIMMYT covered 87% of the wheat area surveyed.

“This research demonstrates that DNA fingerprinting can be applied at scale and is likely to transform future crop varietal adoption studies,” said Kindie Tesfaye, a senior scientist at CIMMYT and co-author of the study. “Additional DNA fingerprinting studies are now also well advanced for maize in Ethiopia.”

This research is supported by the Bill and Melinda Gates Foundation and CGIAR Fund Donors. Financial support was provided through the “Mainstreaming the use and application of DNA Fingerprinting in Ethiopia for tracking crop varieties” project funded by the Bill & Melinda Gates Foundation (Grant number OPP1118996).

RELATED PUBLICATIONS:

Ethiopia’s Transforming Wheat Landscape: Tracking Variety Use through DNA Fingerprinting

FOR FURTHER INFORMATION OR INTERVIEW REQUESTS:

Dave Hodson, International Maize and Wheat Improvement Center (CIMMYT), d.hodson@cgiar.org

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