Posts Tagged ‘wheat diseases’

New publications: Special collection on wheat genetics and breeding

Researchers present highlights from 40 years of collaboration on wheat genomics, breeding for disease resistance and quality improvement.

This article by Emma Orchardson was originally posted on the CIMMYT website.

Wheat rust expert Bob McIntosh, of the Plant Breeding Institute, University of Sydney, Australia, examining rust symptoms on a wheat line in the field at the Kenya Agricultural Research Institute’s (KARI) Njoro research station in Kenya. Photo: CIMMYT/Petr Kosina

Global wheat production is currently facing great challenges, from increasing climate variation to occurrence of various pests and diseases. These factors continue to limit wheat production in a number of countries, including China, where in 2018 unseasonably cold temperatures resulted in yield reduction of more than 10% in major wheat growing regions. Around the same time, Fusarium head blight spread from the Yangtze region to the Yellow and Huai Valleys, and northern China experienced a shortage of irrigated water.

In light of these ongoing challenges, international collaboration, as well as the development of new technologies and their integration with existing ones, has a key role to play in supporting sustainable wheat improvement, especially in developing countries. The International Maize and Wheat Improvement Center (CIMMYT) has been collaborating with China on wheat improvement for over 40 years, driving significant progress in a number of areas.

Notably, a standardized protocol for testing Chinese noodle quality has been established, as has a methodology for breeding adult-plant resistance to yellow rust, leaf rust and powdery mildew. More than 330 cultivars derived from CIMMYT germplasm have been released in the country and are currently grown over 9% of the Chinese wheat production area, while physiological approaches have been used to characterize yield potential and develop high-efficiency phenotyping platforms. The development of climate-resilient cultivars using new technology will be a priority area for future collaboration.

In a special issue of Frontiers of Agricultural Science and Engineering focused on wheat genetics and breeding, CIMMYT researchers present highlights from global progress in wheat genomics, breeding for disease resistance, as well as quality improvement, in a collection of nine review articles and one research article. They emphasize the significance of using new technology for genotyping and phenotyping when developing new cultivars, as well as the importance of global collaboration in responding to ongoing challenges.

In a paper on wheat stem rust, CIMMYT scientists Sridhar Bhavani, David Hodson, Julio Huerta-Espino, Mandeep Randawa and Ravi Singh discuss progress in breeding for resistance to Ug99 and other races of stem rust fungus, complex virulence combinations of which continue to pose a significant threat to global wheat production. The authors detail how effective gene stewardship and new generation breeding materials, complemented by active surveillance and monitoring, have helped to limit major epidemics and increase grain yield potential in key target environments.

In the same issue, an article by Caiyun Lui et al. discusses the application of spectral reflectance indices (SRIs) as proxies to screen for yield potential and heat stress, which is emerging in crop breeding programs. The results of a recent study, which evaluated 287 elite lines, highlight the utility of SRIs as proxies for grain yield. High heritability estimates and the identification of marker-trait associations indicate that SRIs are useful tools for understanding the genetic basis of agronomic and physiological traits.

Other papers by CIMMYT researchers discuss the history, activities and impact of the International Winter Wheat Improvement Program, as well as the ongoing work on the genetic improvement of wheat grain quality at CIMMYT.

Find the full collection of articles in Frontiers of Agricultural Science and Engineering, Volume 6, Issue 3, September 2019.

A wheat self-sufficiency roadmap for Ethiopia’s future

Mechanization could boost Ethiopian wheat production and provide youth with new job opportunities. (Photo: Gerardo Mejía/CIMMYT)

This blog by Jérôme Bousset was originally posted on CIMMYT.org.

The Ethiopian government announced recently that the country should become wheat self-sufficient over the next four years. Why is boosting domestic wheat production important for this country in the Horn of Africa, and could wheat self-sufficiency be attained in the next four years? The Ethiopian Institute for Agricultural Research (EIAR), with the support of International Maize and Wheat Improvement Center (CIMMYT), gathered agriculture and food experts from the government, research and private sectors on November 23, 2018, to draw the first outlines of this new Ethiopian wheat initiative.

The low-tech domestic wheat farming and price support issue

Despite a record harvest of 4.6 million metric tons in 2017, Ethiopia imported 1.5 million tons of wheat the same year, costing US$600 million. Population growth, continuous economic growth and urbanization over the last decade has led to a rapid change in Ethiopian diets, and the wheat sector cannot keep up with the growing demand for pasta, dabo, ambasha and other Ethiopian breads.

The majority of Ethiopia’s 4.2 million wheat farmers cultivate this cereal on an average of 1.2-hectare holdings, with three quarters produced in Arsi, Bale and Shewa regions. Most prepare the land and sow with draft animal power equipment and few inputs, dependent on erratic rainfall without complementary irrigation. Yields have doubled over the last 15 years and reached 2.7 tons per hectare according to the latest agricultural statistics, but are still far from the yield potential.

According to data from the International Food Policy Research Institute (IFPRI), wheat is preferred by wealthier, urban families, who consume 33 percent more wheat than rural households. Ethiopia needs to rethink its wheat price support system, which does not incentivize farmers and benefits mostly the wealthier, urban consumers. Wheat price support subsidies could, for instance, target bakeries located in poor neighborhoods.

 

Ethiopia’s Minister of Agriculture and Natural Resources, Eyasu Abraha, welcomes conference participants. (Photo: Jérôme Bossuet/CIMMYT)

Where to start to boost wheat productivity?

Ethiopia, especially in the highlands, has an optimum environment to grow wheat. But to make significant gains, the wheat sector needs to identify what limiting factors to address first. The Wheat initiative, led by Ethiopia’s Agricultural Transformation Agency (ATA), has targeted 2,000 progressive farmers across 41 woredas (districts) between 2013 and 2018, to promote the use of improved and recommended inputs and better cropping techniques within their communities. A recent IFPRI impact study showed a 14 percent yield increase, almost enough to substitute wheat imports if scaled up across the country. It is, however, far from the doubling of yields expected initially. The study shows that innovations like row planting were not widely adopted because of the additional labor required.

Hans Braun, WHEAT CGIAR research program and CIMMYT’s Global Wheat Program director, believes Ethiopian farmers can achieve self-sufficiency if they have the right seeds, the right agronomy and the right policy support.

One priority is to increase support for wheat improvement research to make wheat farmers more resilient to new diseases and climate shocks. Drought and heat tolerance, rust resistance and high yields even in low-fertility soils are some of the factors sought by wheat farmers.

International collaboration in durum wheat breeding is urgently needed as the area under durum wheat is declining in Ethiopia due to climate change, diseases and farmers switching to more productive and resilient bread wheat varieties. Braun advises that Ethiopia set up a shuttle breeding program with CIMMYT in Mexico, as Kenya did for bread wheat, to develop high-yielding and stress-resistant varieties. Such a shuttle breeding program between Ethiopia and Mexico would quickly benefit Ethiopian durum wheat farmers, aiming at raising their yields similar to those of Mexican farmers in the state of Sonora, who harvest more than 7 tons per hectare under irrigation. This would require a policy reform to facilitate the exchange of durum germplasm between Ethiopia and Mexico, as it is not possible at the moment.

Ethiopia also needs to be equipped to respond quickly to emerging pests and diseases. Five years ago, a new stem rust (TKTTF, also called Digalu race) damaged more than 20,000 hectares of wheat in Arsi and Bale, as Digalu — the popular variety used by local farmers — was sensitive to this new strain. The MARPLE portable rust testing lab, a fast and cost-effective rust surveillance system, is now helping Ethiopian plant health authorities quickly identify new rust strains and take preventive actions to stop new outbreaks.

CIMMYT’s representative in Ethiopia, Bekele Abeyo, gives an interview for Ethiopian media during the conference. (Photo: Jérôme Bossuet/CIMMYT)

Invest in soil health, mechanization and gender

In addition to better access to improved seeds and recommended inputs, better agronomic practices are needed. Scaling the use of irrigation would certainly increase wheat yields, but experts warn not to dismiss adequate agronomic research — knowing the optimal water needs of the crop for each agroecological zone — and the underlying drainage system. Otherwise, farmers are at risk of losing their soils forever due to an accumulation of salt.

‘’2.5 billion tons of topsoil are lost forever every year due to erosion. A long-term plan to address soil erosion and low soil fertility should be a priority,” highlights Marco Quinones, adviser at ATA. For instance, large-scale lime application can solve the important issue of acid soils, where wheat does not perform well. But it requires several years before the soil can be reclaimed and visible yield effects can be seen.

Mechanization could also boost Ethiopian wheat production and provide youth with new job opportunities. Recent research showed smallholder farmers can benefit from six promising two-wheel tractor (2WT) technologies. Identifying the right business models and setting up adapted training programs and financial support will help the establishment of viable machinery service providers across the country.

Better gender equity will also contribute significantly to Ethiopia becoming self-sufficient in wheat production. Women farmers, especially female-headed households, do not have the same access to trainings, credit, inputs or opportunities to experiment with new techniques or seed varieties because of gender norms. Gender transformative methodologies, like community conversations, can help identify collective ways to address such inequalities, which cost over one percent of GDP every year.

‘’With one third better seeds, one third good agronomy and one third good policies, Ethiopia will be able to be wheat self-sufficient,” concluded Braun. A National Wheat Taskforce led by EIAR will start implementing a roadmap in the coming days, with the first effects expected for the next planting season in early 2019.

The consultative workshop “Wheat Self-Sufficiency in Ethiopia: Challenges and Opportunities” took place in Addis Ababa, Ethiopia, on November 23, 2018.

Inspiring millennials to focus on food security: The power of mentorship

by Mike Listman, November 13, 2018

As part of their education, students worldwide learn about the formidable challenges their generation faces, including food shortages, climate change, and degrading soil health. Mentors and educators can either overwhelm them with reality or motivate them by real stories and showing them that they have a role to play. Every year the World Food Prize lives out the latter by introducing high school students to global food issues at the annual Borlaug Dialogue, giving them an opportunity to interact with “change agents” who address food security issues. The World Food Prize offers some students an opportunity to intern at an international research center through the Borlaug-Ruan International Internship program.
Tessa Mahmoudi

Tessa Mahmoudi, plant microbiologist and 2012 World Food Prize Borlaug-Ruan summer intern, credits the mentorship of CIMMYT researchers in Turkey with changing her outlook on the potential of science to improve food security and health. (Photo: University of Minnesota).

Plant Microbiologist Tessa Mahmoudi, a 2012 World Food Prize’s Borlaug-Ruan summer intern, says her experience working with CIMMYT researchers in Turkey when she was 16 years old profoundly changed her career and her life.

“For a summer I was welcomed to Turkey not as a child, but as a scientist,” says Mahmoudi, who grew up on a farm in southeast Minnesota, USA. “My hosts, Dr. Abdelfattah A. Dababat and Dr. Gül Erginbas-Orakci, who study soil-borne pathogens and the impact those organisms have on food supplies, showed me their challenges and, most importantly, their dedication.”

Mahmoudi explains she still finds the statistics regarding the global food insecurity to be daunting but saw CIMMYT researchers making real progress. “This helped me realize that I had a role to play and an opportunity to make positive impact.”

Among other things, Mahmoudi learned what it meant to be a plant pathologist and the value of that work. “I began to ask scientific questions that mattered,” she says. “And I went back home motivated to study — not just to get good grades, but to solve real problems.”

She says her outlook on the world dramatically broadened. “I realized we all live in unique realities, sheltered by climatic conditions that strongly influence our world views.”

According to Mahmoudi, her internship at CIMMYT empowered her to get out of her comfort zone and get involved in food security issues. She joined the “hunger fighters” at the University of Minnesota while pursuing a bachelor’s in Plant Science. “I was the president of the Project Food Security Club which focuses on bring awareness of global hunger issues and encouraging involvement in solutions.” She also did research on stem rust under Matthew Rouse, winner of the World Food Prize 2018  Norman Borlaug Award for Field Research and Application.

Pursuing a master’s in plant pathology at Texas A&M University under the supervision of Betsy Pierson, she studied the effects of plant-microbe interactions on drought tolerance and, specifically, how plant-microbe symbiosis influences root architecture and wheat’s ability to recover after suffering water stress.

Mahmoudi incorporates interactive learning activities in her class (see her website, https://reachingroots.org/). Her vision is to increase access to plant science education and encourage innovation in agriculture.Currently, Mahmoudi is involved in international development and teaching. As a horticulture lecturer at Blinn College in Texas, she engages students in the innovative use of plants to improve food security and global health.

“As a teacher and mentor, I am committed to helping students broaden their exposure to real problems because I know how much that influenced me,” Mahmoudi says. “Our world has many challenges, but great teams and projects are making progress, such as the work by CIMMYT teams around the world. We all have a role to play and an idea that we can make a reality to improve global health.”

As an example, Mahmoudi is working with the non-profit Clean Challenge on a project to improve the waste system in Haiti. The initiative links with local teams in Haiti to develop a holistic system for handling trash, including composting organic waste to empower small holder farmers to improve their soil health and food security.

“Without my mentors, I would not have had the opportunity to be involved in these high impact initiatives. Wherever you are in your career make sure you are being mentored and also mentoring. I highly encourage students to find mentors and get involved in today’s greatest challenge, increasing food security.”

In addition to thanking the CIMMYT scientists who inspired her, Mahmoudi is deeply grateful for those who made her summer internship possible. “This would include the World Food Prize Foundation and especially Lisa Fleming, Ambassador Kenneth M. Quinn, the Ruan Family,” she says. “Your commitment to this high-impact, experiential learning opportunity has had lasting impact on my life.”

Mutating diseases drive wheat variety turnover in Ethiopia, new study shows

Yellow spores of the fungus Puccinia striiformis f.sp. tritici, which causes stripe rust disease in wheat. Photo: CIMMYT/Mike Listman.

By Mike Listman

Rapidly emerging and evolving races of wheat stem rust and stripe rust disease—the crop’s deadliest scourges worldwide—drove large-scale seed replacement by Ethiopia’s farmers during 2009-14, as the genetic resistance of widely-grown wheat varieties no longer proved effective against the novel pathogen strains, according to a new study by the International Maize and Wheat Improvement Center (CIMMYT).

Based on two surveys conducted by CIMMYT and the Ethiopian Institute of Agricultural Research (EIAR) and involving more than 2,000 Ethiopian wheat farmers, the study shows that farmers need access to a range of genetically diverse wheat varieties whose resistance is based on multiple genes.

After a severe outbreak in 2010-11 of a previously unseen stripe rust strain, 40 percent of the affected farm households quickly replaced popular but susceptible wheat varieties, according to Moti Jaleta, agricultural economist at CIMMYT and co-author of the publication.

“That epidemic hit about 600,000 hectares of wheat—30 percent of Ethiopia’s wheat lands—and farmers said it cut their yields in half,” Jaleta said. “In general, the rapid appearance and mutation of wheat rust races in Ethiopia has convinced farmers about the need to adopt newer, resistant varieties.”

The fourth most widely grown cereal after tef, maize, and sorghum, wheat in Ethiopia is produced largely by smallholder farmers under rainfed conditions. Wheat production and area under cultivation have increased significantly in the last decade and Ethiopia is among Africa’s top three wheat producers, but the country still imports on average 1.4 million tons of wheat per year to meet domestic demand.

National and international organizations such as EIAR, CIMMYT, and the International Centre for Agricultural Research in the Dry Areas (ICARDA) are working intensely to identify and incorporate new sources of disease resistance into improved wheat varieties and to support the multiplication of more seed to meet farmer demand.

New wheat varieties have provided bigger harvests and incomes for Ethiopia farmers in the last decade, but swiftly mutating and spreading disease strains are endangering wheat’s future, according to Dave Hodson, CIMMYT expert in geographic information and decision support systems, co-author of the new study.

Ethiopian wheat farmers like Abebe Abora, of Doyogena, have benefitted from adopting high-yielding wheat varieties but face threats from fast mutating races of wheat rust disease pathogens. Photo: CIMMYT/Apollo Habtamu.

Ethiopian wheat farmers like Abebe Abora, of Doyogena, have benefitted from adopting high-yielding wheat varieties but face threats from fast mutating races of wheat rust disease pathogens. Photo: CIMMYT/Apollo Habtamu.

“In addition to stripe rust, highly-virulent new races of stem rust are ruining wheat harvests in eastern Africa,” he explained. “These include the deadly Ug99 race group, which has spread beyond the region, and, more recently, the stem rust race TKTTF.”

As an example, he mentioned the case of the wheat variety Digalu, which is resistant to stripe rust and was quickly adopted by farmers after the 2010-11 epidemic. But Digalu has recently shown susceptibility to TKTTF stem rust and must now be replaced.

“In rust-prone Ethiopia, the risks of over-reliance on a widely-sown variety that is protected by a single, major resistance gene—Digalu, for example—are clearly apparent,” he added. “CIMMYT and partners are working hard to replace it with a new variety whose resistance is genetically more complex and durable.”

Hodson said as well that continuous monitoring of the rust populations in Ethiopia and the surrounding region is essential to detect and respond to emerging threats, as well as to ensure that the key pathogen races are used to screen for resistance in wheat breeding programs.

Hodson and partners at the John Innes Centre, UK, and EIAR are leading development of a handheld tool that allows rapid identification of disease strains in the field, instead of having to send them to a laboratory and lose precious time awaiting the results.

CIMMYT and partners are also applying molecular tools to study wheat varietal use in Ethiopia. “There are indications that yields reported by farmers were much lower than official statistics, and farmer recollections of varietal names and other information are not always exact,” Hodson explained. “We are analyzing results now of a follow-up study that uses DNA fingerprinting to better document varietal use and turnover.”

The authors would like to acknowledge the Standing Panel for Impact Assessment (SPIA) for financing, the Diffusion and Impacts of Improved Varieties in Africa (DIIVA) project that supported the first survey in 2011, and Cornell Universitythe Bill & Melinda Gates Foundation, and United Kingdom’s Department for International Development (DFID) through the Durable Rust Resistance in Wheat (DRRW, now called Delivering Genetic Gain in Wheat) project for support for the second survey in 2014.

Wheat blast screening and surveillance training in Bangladesh

Photo: CIMMYT/Tim Krupnik

Fourteen young wheat researchers from South Asia recently attended a screening and surveillance course to address wheat blast, the mysterious and deadly disease whose surprise 2016 outbreak in southwestern Bangladesh devastated that region’s wheat crop, diminished farmers’ food security and livelihoods, and augured blast’s inexorable spread in South Asia.

Held from 24 February to 4 March 2018 at the Regional Agricultural Research Station (RARS), Jessore, as part of that facility’s precision phenotyping platform to develop resistant wheat varieties, the course emphasized hands-on practice for crucial and challenging aspects of disease control and resistance breeding, including scoring infections on plants and achieving optimal development of the disease on experimental wheat plots.

Cutting-edge approaches tested for the first time in South Asia included use of smartphone-attachable field microscopes together with artificial intelligence processing of images, allowing researchers identify blast lesions not visible to the naked eye.

“A disease like wheat blast, which respects no borders, can only be addressed through international collaboration and strengthening South Asia’s human and institutional capacities,” said Hans-Joachim Braun, director of the global wheat program of the International Maize and Wheat Improvement Center (CIMMYT), addressing participants and guests at the course opening ceremony. “Stable funding from CGIAR enabled CIMMYT and partners to react quickly to the 2016 outbreak, screening breeding lines in Bolivia and working with USDA-ARS, Fort Detrick, USA to identify resistance sources, resulting in the rapid release in 2017 of BARI Gom 33, Bangladesh’s first-ever blast resistant and zinc enriched wheat variety.”

Cooler and dryer weather during the 2017-18 wheat season has limited the incidence and severity of blast on Bangladesh’s latest wheat crop, but the disease remains a major threat for the country and its neighbors, according to P.K. Malaker, Chief Scientific Officer, Wheat Research Centre (WRC) of the Bangladesh Agricultural Research Institute (BARI).

“We need to raise awareness of the danger and the need for effective management, through training courses, workshops, and mass media campaigns,” said Malaker, speaking during the course.

The course was organized by CIMMYT, a Mexico-based organization that has collaborated with Bangladeshi research organizations for decades, with support from the Australian Center for International Agricultural Research (ACIAR), Indian Council of Agricultural Research (ICAR), CGIAR Research Program on Wheat (WHEAT), the United States Agency for International Development (USAID), and the Bangladesh Wheat and Maize Research Institute (BWMRI).

Speaking at the closing ceremony, N.C.D. Barma, WRC Director, thanked the participants and the management team and distributed certificates. “The training was very effective. BMWRI and CIMMYT have to work together to mitigate the threat of wheat blast in Bangladesh.”

Other participants included Jose Mauricio Fernandes, EMBRAPA-Passo Fundo, Brazil; Pawan Singh, CIMMYT wheat pathologist; T.P. Tiwari, Timothy J. Krupnik, and D.B. Pandit, CIMMYT-Bangladesh; Bahadur Mia, Bangladesh Agricultural University (BAU); and scientists from BMWRI and BARI, the Nepal Agricultural Research Council NARC, and Assam Agricultural University (AAU), India.

Young women scientists who will galvanize global wheat research

By Laura Strugnell and Mike Listman

Winners of the Jeanie Borlaug Laube Women in Triticum (WIT) Early Career Award pose in front of the statue of the late Nobel Peace laureate, Dr. Norman E. Borlaug. Included in the photo are Amor Yahyaoui, CIMMYT wheat training coordinator (far left), Jeanie Borlaug Laube (center, blue blouse), and Maricelis Acevedo, Associate Director for Science, the Delivering Genetic Gain in Wheat Project (to the right of Jeanie Borlaug Laube). Photo: CIMMYT/Mike Listman

CIUDAD OBREGÓN, Mexico (CIMMYT) – As more than 200 wheat science and food specialists from 34 countries gathered in northwestern Mexico to address threats to global nutrition and food security, 9 outstanding young women wheat scientists among them showed that this effort will be strengthened by diversity.

Winners of the Jeanie Borlaug Laube Women in Triticum (WIT) Early Career Award joined an on-going wheat research training course organized by the International Maize and Wheat Improvement Center (CIMMYT), 21-23 March.

“As my father used to say, you are the future,” said Jeanie Borlaug Laube, daughter of the late Nobel Peace Prize laureate, Dr. Norman E. Borlaug, and mentor of many young agricultural scientists. Speaking to the WIT recipients, she said, “You are ahead of the game compared to other scientists your age.”

Established in 2010 as part of the Delivering Genetic Gain in Wheat (DGGW) project led by Cornell University, the WIT program has provided professional development opportunities for 44 young women researchers in wheat from more than 20 countries.

The award is given annually to as many as five early science-career women, ranging from advanced undergraduates to recent doctoral graduates and postdoctoral fellows. Selection is based on a scientific abstract and statement of intent, along with evidence of commitment to agricultural development and leadership potential.

Women who will change their professions and the world

Weizhen Liu. Photo: WIT files

Weizhen Liu, a 2017 WIT recipient and postdoctoral researcher at Cornell University, is applying genome-wide association mapping and DNA marker technology to enhance genetic resistance in tetraploid and bread wheat to stripe rust, a major global disease of wheat that is quickly spreading and becoming more virulent.

“I am eager to join and devote myself to improving wheat yields by fighting wheat rusts,” said Liu, who received her bachelors in biotechnology from Nanjing Agricultural University, China, in 2011, and a doctorate from Washington State University in 2016. “Through WIT, I can share my research with other scientists, receive professional feedback, and build international collaboration.”

Mitaly Bansal, a 2016 WIT award winner, currently works as a Research Associate at Punjab Agricultural University, India. She did her PhD research in a collaborative project involving Punjab Agricultural University and the John Innes Centre, UK, to deploy stripe and leaf rust resistance genes from non-progenitor wild wheat in commercial cultivars.

Mitaly Bansal. Photo: WIT files

“I would like to work someday in a position of public policy in India,” said Bansal, who received the Monsanto Beachell-Borlaug scholarship in 2013. “That is where I could have the influence to change things that needed changing.”

Networking in the cradle of wheat’s “Green Revolution”

In addition to joining CIMMYT training for a week, WIT recipients will attend the annual Borlaug Global Rust Initiative (BGRI) technical workshop, to be held this year in Marrakech, Morocco, from 14 to 17 April, and where the 2018 WIT winners will be announced.

The CIMMYT training sessions took place at the Norman Borlaug Experiment Station (CENEB), an irrigated desert location in Sonora State, northwestern Mexico, and coincided with CIMMYT’s 2018 “Visitors’ Week,” which took place from 19 to 23 March.

An annual gathering organized by the CIMMYT global wheat program at CENEB, Visitors’ Week typically draws hundreds of experts from the worldwide wheat research and development community. Participants share innovations and news on critical issues, such as the rising threat of the rust diseases or changing climates in key wheat farmlands.

Through her interaction with Visitors’ Week peers, Liu said she was impressed by the extensive partnering among experts from so many countries. “I realized that one of the most important things to fight world hunger is collaboration; no one can solve food insecurity, malnutrition, and climate change issues all by himself.”

A strong proponent and practitioner of collaboration, Norman E. Borlaug worked with Sonora farmers in the 1940-50s as part of a joint Rockefeller Foundation-Mexican government program that, among other outputs, generated high-yielding, disease-resistant wheat varieties. After bringing wheat self-sufficiency to Mexico, the varieties were adopted in South Asia and beyond in the 1960-70s, dramatically boosting yields and allowing famine-prone countries to feed their rapidly-expanding populations.

This became known as the Green Revolution and, in 1970, Borlaug received the Nobel Peace Prize in recognition of his contributions. Borlaug subsequently led CIMMYT wheat research until his retirement in 1979 and served afterwards as a special consultant to the Center.

When a new, highly virulent race of wheat stem rust, Ug99, emerged in eastern Africa in the early 2000s, Borlaug sounded the alarm and championed a global response that grew into the BGRI and associated initiatives such as DGGW.

“This is just a beginning for you, but it doesn’t end here,” said Maricelis Acevedo, a former WIT recipient who went on to become the leader of DGGW. Speaking during the training course, she observed that many WIT awardees come from settings where women often lack access to higher education or the freedom to pursue a career.

“Through WIT activities, including training courses like this and events such as Visitors’ Week and the BGRI workshop,” Acevedo added, “you’ll gain essential knowledge and skills but you’ll also learn leadership and the personal confidence to speak out, as well as the ability to interact one-on-one with leaders in your field and to ask the right questions.”

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 Research Programs on Maize and Wheat and the Excellence in Breeding Platform. The Center receives generous support from national governments, foundations, development banks and other public and private agencies.

Funded by the Bill & Melinda Gates Foundation and the UK’s Department for International Development (DFID) under UK aid, the DGGW project aims to strengthen the delivery pipeline for new, disease resistant, climate-resilient wheat varieties and to increase the yields of smallholder wheat farmers.

 

Deadly strain of wheat stem rust disease surfaces in Europe

Scientists have shown that the first appearance of wheat stem rust disease in the U.K. in nearly 60 years, which occurred in 2013, was caused by the same virulent fungal strain responsible for recent wheat stem rust outbreaks in Ethiopia, Denmark, Germany, and Sweden.

Wheat stem rust was reported by the Greeks and Romans, and the latter sacrificed to the gods to avoid disease outbreaks on their wheat crops. Photo: CIMMYT/Petr Kosina

Wheat stem rust was reported by the Greeks and Romans, and the latter sacrificed
to the gods to avoid disease outbreaks on their wheat crops.
Photo: CIMMYT/Petr Kosina

As reported today in Communications Biology, an international team of researchers led by the John Innes Centre, U.K., found that 80 percent of U.K. wheat varieties are susceptible to the deadly stem rust strain. The group also confirmed for the first time in many decades that the stem rust fungus was growing on barberry bush, the pathogen’s alternate host, in the UK.

“This signals the rising threat of stem rust disease for wheat and barley production in Europe,” said Dave Hodson, senior scientist at the International Maize and Wheat Improvement Center (CIMMYT) and co-author on the study.

A scourge of wheat since biblical times, stem rust caused major losses to North American wheat crops in the early 20th century. Stem rust disease was controlled for decades through the use of resistant wheat varieties bred in the 1950s by scientist Norman Borlaug and his colleagues. Widespread adoption of those varieties sparked the Green Revolution of the 1960s and 70s.

In 1999 a new, highly-virulent strain of the stem rust fungus emerged in eastern Africa. Spores of that strain and variants have spread rapidly and are threatening or overcoming the genetic resistance of many currently sown wheat varieties. Scientists worldwide joined forces in the early 2000s to develop new, resistant varieties and to monitor and control outbreaks of stem rust and yellow rust, as part of collaborations such as the Borlaug Global Rust Initiative led by Cornell University.

Barberry is a shrub found throughout the temperate and subtropical regions. Photo: CIMMYT archives

Barberry is a shrub found throughout
the temperate and subtropical regions.
Photo: John Innes Centre

The Communications Biology study shows that 2013 U.K. stem rust strain is related to TKTTF, a fungal race first detected in Turkey that spread across the Middle East and recently into Europe. It was the dominant race in the 2013 stem rust outbreak in Germany and infected 10,000 hectares of wheat in Ethiopia’s breadbasket the same year.

Because disease organisms mutate quickly to overcome crop resistance controlled by single genes, researchers are rushing to identify new resistance genes and to incorporate multiple genes into high-yielding varieties, according to Ravi Singh, CIMMYT wheat scientist who participated in the reported study.

“The greatest hope for achieving durable resistance to rust diseases is to make wheat’s resistance genetically complex, combining several genes and resistance mechanisms,” Singh explained.

Barberry, which serves as a spawning ground for the stem rust fungus, was largely eradicated from the U.K. and U.S. last century, greatly reducing the spread and genetic diversification of rust disease races. Now barberry is being grown again in the U.K. over the last decade, according to Diane G.O. Saunders, John Innes Centre scientist and co-author of the study.

“The late Nobel laureate Norman Borlaug said that the greatest ally of the pathogen is our short memory,” Saunders stated. “We recommend continued, intensive resistance breeding. We would also welcome work with conservationists of endangered, barberry-dependent insect species to ensure that planting of common barberry occurs away from arable land, thus safeguarding European cereals from a large-scale re-emergence of wheat stem rust.”

Click here to read the John Innes Centre media release about the Communications Biology report and view the report.

Goat grass gives wheat breeders an edge

31 January 2018
by Laura Strugnell

A commentary published on 30 January in the leading science journal Nature Plants highlights the importance of an ancient grass species for wheat breeding. The commentary was sparked by the recent publication of a reference genome from Aegilops tauschii, also called goat grass.

Bread wheat was created some 10,000 years ago by a natural cross of more simple, primitive wheats with a sub-species of goat grass. As such, goat grass genes constitute a major component of the very large wheat genome. The sequencing of goat grass DNA opens the way for wheat breeders to apply a number of advanced approaches to improve the speed and precision of wheat breeding for important traits that may be found in the goat grass segment of the wheat genome.

The International Maize and Wheat Improvement Center (CIMMYT) and the International Centre for Agricultural Research in the Dry Areas (ICARDA) have produced many wheat x grass crosses, recreating the original, natural cross but using other goat grass species and thus greatly expanding wheat’s diversity. Wheat lines derived from those crosses have since been used in breeding programs worldwide and have helped farmers to boost yields by up to 20 percent. Goat grass is known for being highly adaptable and disease tolerant, so the crosses endow wheat with similar qualities. Varieties from these crosses make up over 30 percent of international seed stores.

Researchers expect that the sequencing of this grass species’ DNA will facilitate advanced approaches such as “speed breeding” – a technique that uses controlled variables to achieve up to seven rounds of wheat crops in one year. This will help allow wheat breeding to keep up with the rising global demand for the crop and to address the challenges of new, virulent diseases and more extreme weather.

Read the Nature Plants article: The goat grass genome’s role in wheat improvement. 2018. Rasheed, A., Ogbonnaya, F.C., Lagudah, E., Appels, R., He, Z. In: Nature Plants.

Breakthrough in the battle against Ug99

Melania Figuroa and Peter Dodds
Thursday, January 25, 2018 (Posted on the Borlaug Global Rust Initiative web page)

Wheat stem rust at important flag leaf stage. Photo by Robert Park

A significant breakthrough in combatting wheat stem rust disease caused by the fungus Puccinia graminis f. sp. tritici was recently achieved through the combined work of an international collaborative team, showing the power of cooperative research approaches.

The emergence of the Ug99 race of stem rust in Africa and the Middle East together with the appearance of new strains in Europe catalyzed a major effort to identify new sources of stem rust resistance and breed these genes into wheat lines. However, the continued emergence of stem rust variants that overcome new resistance genes, now demands an increased focus on pathogen evolution and virulence mechanisms.

Numerous stem rust resistance (Sr) genes are known and in recent years several of these have been cloned and used to develop so-called ‘perfect’ markers to allow more rapid and accurate breeding. These genes typically encode immune receptors that recognize specific protein components of the fungal pathogen to trigger resistance. However, the molecules recognized by these Sr genes have been unknown until now, hampering our understanding of how new strains of P. graminis f. sp. tritici evolve to escape plant recognition.

New insight into this evolution came from the identification of the protein, AvrSr50, which is recognized by the wheat Sr50 resistance gene, by  an international collaboration led by Dr. Peter Dodds (CSIRO Food and Agriculture and University of Minnesota Adjunct Professor) and Professor Robert Park (University of Sydney and Director of theAustralian Cereal Rust Control Program) and involving teams in the UK and the US.

Click here to read the full article.