Posts Tagged ‘wheat blast’

What is wheat blast?

This article by Matthew O’ Leary was originally posted on the CIMMYT website.

Wheat blast is a fast-acting and devastating fungal disease that threatens food safety and security in tropical areas in South America and South Asia. Directly striking the wheat ear, wheat blast can shrivel and deform the grain in less than a week from the first symptoms, leaving farmers no time to act.

The disease, caused by the fungus Magnaporthe oryzae pathotype triticum (MoT), can spread through infected seeds and survives on crop residues, as well as by spores that can travel long distances in the air.

Magnaporthe oryzae can infect many grasses, including barley, lolium, rice, and wheat, but specific isolates of this pathogen generally infect limited species; that is, wheat isolates infect preferably wheat plants but can use several more cereal and grass species as alternate hosts. The Bangladesh wheat blast isolate is being studied to determine its host range. The Magnaporthe oryzae genome is well-studied but major gaps remain in knowledge about its epidemiology.

The pathogen can infect all aerial wheat plant parts, but maximum damage is done when it infects the wheat ear. It can shrivel and deform the grain in less than a week from first symptoms, leaving farmers no time to act.
The pathogen can infect all aerial wheat plant parts, but maximum damage is done when it infects the wheat ear. It can shrivel and deform the grain in less than a week from first symptoms, leaving farmers no time to act.

Where is wheat blast found?

First officially identified in Brazil in 1985, the disease is widespread in South American wheat fields, affecting as much as 3 million hectares in the early 1990s. It continues to seriously threaten the potential for wheat cropping in the region.

In 2016, wheat blast spread to Bangladesh, which suffered a severe outbreak. It has impacted around 15,000 hectares of land in eight districts, reducing yield on average by as much as 51% in the affected fields.

Wheat-producing countries and presence of wheat blast.
Wheat-producing countries and presence of wheat blast.

How does blast infect a wheat crop?

Wheat blast spreads through infected seeds, crop residues as well as by spores that can travel long distances in the air.

Blast appears sporadically on wheat and grows well on numerous other plants and crops, so rotations do not control it. The irregular frequency of outbreaks also makes it hard to understand or predict the precise conditions for disease development, or to methodically select resistant wheat lines.

At present blast requires concurrent heat and humidity to develop and is confined to areas with those conditions. However, crop fungi are known to mutate and adapt to new conditions, which should be considered in management efforts.

How can farmers prevent and manage wheat blast?

There are no widely available resistant varieties, and fungicides are expensive and provide only a partial defense. They are also often hard to obtain or use in the regions where blast occurs, and must be applied well before any symptoms appear — a prohibitive expense for many farmers.

The Magnaporthe oryzae fungus is physiologically and genetically complex, so even after more than three decades, scientists do not fully understand how it interacts with wheat or which genes in wheat confer durable resistance.

Researchers from the International Maize and Wheat Improvement Center (CIMMYT) are partnering with national researchers and meteorological agencies on ways to work towards solutions to mitigate the threat of wheat blast and increase the resilience of smallholder farmers in the region. Through the USAID-supported Cereal Systems Initiative for South Asia (CSISA) and Climate Services for Resilient Development (CSRD) projects, CIMMYT and its partners are developing agronomic methods and early warning systems so farmers can prepare for and reduce the impact of wheat blast.

Digital Warning System Boosts Resilience in Bangladesh

Farmers around the world face a constant threat from crop diseases, but digital tools are making it easier for farmers to prepare for outbreaks.

This story by Matt O’Leary was originally published on the USAID Feed the Future blog.

Farmers around the world face constant threats from crop pests and diseases. One such threat is wheat blast, a disease that attacks maturing grains, causing them to shrivel. Fortunately, new advances in technology and modeling are making it easier to identify, prevent and control diseases like this.

Outbreaks of wheat blast in South Asia — a region where people consume over 100 million tons of wheat each year — have a major impact on food security and income. In 2016, a wheat blast outbreak struck South Asia unexpectedly. In Bangladesh alone, 25 to 30 percent of wheat was negatively affected, threatening progress in regional food security. Blast disease has the potential to reduce wheat production by up to 85 million tons in Bangladesh — a projected $13 million loss in farmers’ profits each year when an outbreak occurs.

Luckily, with support from Feed the Future and its partners, there is a reason for hope. A new digital early warning system can help farmers and scientists get ahead. It integrates mathematical models that, when combined with weather forecasts, can simulate disease growth and risks to provide an advanced warning about potential wheat blast outbreaks. With three years of data already recorded, the system — originally piloted in Brazil, where the wheat blast originated in 1985 — is being rolled out across Bangladesh to deliver real-time disease updates to extension workers and smallholder farmers via SMS and voice message.

“Through collaborative research with Professor Jose Mauricio Fernandes, a crop pathologist from Embrapa, and Mr. Felipe de Vargas, a computer scientist with Universidade de Passo Fundo, we have established a model to identify areas at risk of wheat blast infection with five days advanced warning,” said Timothy J. Krupnik, senior scientist and systems agronomist at the International Maize and Wheat Improvement Centre (CIMMYT). “It can provide Bangladesh’s 1.2 million wheat farmers a head start against this disease.”

This data-driven early warning system analyzes environmental conditions for potential disease development in crucial wheat-growing areas of Bangladesh and Brazil. Using this information, the system generates forecast maps and automatic advice for farmers of where and when an outbreak is most likely to strike.

This innovation can also save wheat farmers money. Many apply fungicides on a calendar basis — between two to three times per season — as a preventative measure. This is costly and risks negative environmental effects. Now, the early warning system can push advice to extension agents and farmers, indicating when disease control is really needed.

“Our hope is that it will help reduce unnecessary fungicide use and empower farmers to implement cost-effective and resilient practices to overcome wheat blast risks instead,” Krupnik said.

With wheat as a key crop in Bangladesh, the digital warning system will help prepare farmers to get a head start to reduce the impact of wheat blast with crucial advice from extension agents in areas of need.

Bangladesh leads the way in global fight against wheat blast

An ongoing project was praised for its swift progress in the fight against wheat blast in Bangladesh and South Asia

Eric Huttner, ACIAR Research Program Manager speaking at last month’s mid-term review on wheat blast in Bangladesh and South Asia

At a mid-term review event last month at the BRAC Learning Centre in Dinajpur, Bangladesh, professionals from the Bangladesh Ministry of Agriculture, the Bangladesh Wheat and Maize Research Institute (BWMRI), the Bangladesh Agriculture Research Institute (BARI), the Department of Agriculture Extension (DAE), the Krishi Gobeshona Foundation (KGF), the Bangladesh Agriculture Development Corporation (BADC) and the International Maize and Wheat Improvement Center (CIMMYT) discussed progress made in the battle against wheat blast in Bangladesh and South Asia.

Wheat blast is a fast-acting and devastating fungal disease that threatens wheat production and food security in South America and South Asia. The disease, which originated in South America and first appeared in Bangladesh in 2016, can by dispersed by wind across large distances and spores can be seed borne. There is deep concern among scientists that the disease could spread further across South Asia. A 2018 ex-ante analysis found that in Bangladesh, India and Pakistan wheat blast could potentially cause losses of 0.89 – 1.77 million tons each year, with 7 million hectares of growing area at risk.

In 2017, CIMMYT, BWMRI and the Instituto Nacional de Innovación Agropecuaria y Forestal (INIAF) in Bolivia joined forces in an international effort to tackle wheat blast through widespread adoption of blast resistant wheat varieties.

The project, funded by the Australian Centre for International Agricultural Research (ACIAR) addresses wheat blast in Bangladesh and South Asia through the identification of new sources of resistance genes for wheat blast and development of wheat blast resistant varieties. The germplasm, genes and markers, and genetic information developed through the project are shared with South Asian national wheat breeding programs and other researchers, finally ending up in farmers’ fields as resistant varieties.

The review meeting was chaired by BWMRI Director General Israil Hossain, and featured remarks by Bangladesh’s Additional Secretary of the Ministry of Agriculture Kamala Ranjan Das.

“This project has over-delivered on its milestones,” said Eric Huttner, ACIAR Research Program Manager and lead of the review. “It’s very likely that the project will reduce the risk of blast on wheat production in Bangladesh.”

Early impacts in terms of research capacity and infrastructure are very clear:

  • The project-established precision phenotyping platform in Jashore — the first of its kind in Bangladesh and the region —  is running at full capacity, screening for blast in wheat germplasm materials from as far away as China, the United States and Europe.  The facility currently has the capacity to evaluate almost 5,000 wheat germplasm materials per season and there are ongoing plans for expansion and improvement.
  • Sixty-nine researchers and development professionals, including 9 women, have benefited from the capacity development activities.
  • Molecular research is also making progress. Pawan Singh, project leader and head of Wheat Pathology at CIMMYT, noted that the rapid response was possible due to collective and collaborative action by research partners in this project and beyond.

Meeting attendees emphasized the urgency and importance of the project, which is set to conclude in 2021, in the battle against a fast-moving and devastating disease.

As Huttner told attendees, “Now the resistant or tolerant materials need to be efficiently deployed for breeding high-performance wheat varieties that reach stakeholders as early as possible.”

The Identification of sources of resistance to wheat blast and their deployment in wheat varieties adapted to Bangladesh project is funded by the Australian Centre for International Agricultural Research, with Bangladesh Wheat and Maize Research Institute and the National Institute of Agricultural and Forestry Innovation as key partners. More information about the project can be found on the project factsheet.

WHEAT contributes to G20 agricultural research agenda

Wheat spikes damaged by blast. Photo: CIMMYT

Lead agricultural scientists from G20 member countries gathered in Tokyo, Japan last month to discuss ways to promote science and technology as mechanisms to support the global food system.

The Meeting of Agricultural Chief Scientists (MACS), which took place on April 25-26 in Tokyo, focused on identifying global research priorities in agriculture and ways to facilitate collaboration among G20 members and with relevant stakeholders.  The purpose is to develop a global agenda ahead of the May 11-12 meeting of G20 Agricultural Ministers.

CGIAR Research Program on Wheat (WHEAT) Program Manager Victor Kommerell was among the attendees.

“It is essential to advocate for science-based decision making,” he said. “Better connecting the dots between national agricultural research agendas and the CGIAR international agenda is important. The G20 wheat initiative and WHEAT have made a good start.”

The threat of pests and the importance of adopting climate smart technology came up as high priorities.

Transboundary pests have become a serious threat to food security, exacerbated by the globalized movement of people and commodities and the changing climate. As Kommerell commented to the attendees, pathogens and pests cause global crop losses of 20 to 30 percent. This has a “double penalty” effect, wasting both food and resources invested in farming inputs.

The International Maize and Wheat Improvement Center (CIMMYT) is particularly focused on pests and diseases threatening maize and wheat, such as Fall armyworm and wheat rust and blast.  Kommerell summarized a number of research-based solutions underway thanks to international collaboration – including building globally-accessible rapid screening facilities and using wild crop relatives as a genetic source for resistance. But non-technical solutions, such as boosting awareness and communicating preventative farming practices are also important.

The agricultural field is especially vulnerable to the effects of changing climate and weather variability, while at the same time heavily contributing as a source of greenhouse gases. Innovative agricultural technologies and practices are essential for sustainable production, climate resilience and carbon sequestration as well as reducing greenhouse gas emissions.  

The key, the attendees concluded in a meeting communiqué, is the open and international exchange of knowledge, experience, and practices. Networks are already in place, but need strengthening at both the regional and international level.

To that end, a task force led by Australia and the United States will develop guidelines for working groups and initiatives designed to mitigate pests and scale adoption of climate smart technologies.

The government of Japan is also taking an active role, with plans to hold international conferences this year to facilitate sharing of experiences, research, and best practices from G20 countries.

Assessing the effectiveness of a “wheat holiday” for preventing blast

Policy to encourage alternative crops for wheat farmers in South Asia a short-term solution at best, say CIMMYT researchers

The grain in this blast-blighted wheat head has been turned to chaff.
Photo: CKnight/ DGGW/ Cornell University

Wheat blast — one of the world’s most devastating wheat diseases — is moving swiftly into new territory in South Asia.

In an attempt to curb the spread of this disease, policymakers in the region are considering a “wheat holiday” policy: banning wheat cultivation for a few years in targeted areas. Since wheat blast’s Magnaporthe oryzae pathotype triticum (MoT) fungus can survive on seeds for up to 22 months, the idea is to replace wheat with other crops, temporarily, to cause the spores to die. In India, which shares a border of more than 4,000 km with Bangladesh, the West Bengal state government has already instituted a two-year ban on wheat cultivation in two districts, as well as all border areas. In Bangladesh, the government is implementing the policy indirectly by discouraging wheat cultivation in the severely blast affected districts.

CIMMYT researchers recently published in two ex-ante studies to identify economically feasible alternative crops in Bangladesh and the bordering Indian state of West Bengal.

Alternate crops

The first step to ensuring that a ban does not threaten the food security and livelihoods of smallholder farmers, the authors assert, is to supply farmers with economically feasible alternative crops.

In Bangladesh, the authors examined the economic feasibility of seven crops as an alternative to wheat, first in the entire country, then in 42 districts vulnerable to blast, and finally in ten districts affected by wheat blast. Considering the cost of production and revenue per hectare, the study ruled out boro rice, chickpeas and potatoes as feasible alternatives to wheat due to their negative net return. In contrast, they found that cultivation of maize, lentils, onions, and garlic could be profitable.

The study in India looked at ten crops grown under similar conditions as wheat in the state of West Bengal, examining the economic viability of each. The authors conclude that growing maize, lentils, legumes such aschickpeas and urad bean, rapeseed, mustard and potatoes in place of wheat appears to be profitable, although they warn that more rigorous research and data are needed to confirm and support this transition.

Selecting alternative crops is no easy task. Crops offered to farmers to replace wheat must be appropriate for the agroecological zone and should not require additional investments for irrigation, inputs or storage facilities. Also, the extra production of labor-intensive and export-oriented crops, such as maize in India and potatoes in Bangladesh, may add costs or require new markets for export.

There is also the added worry that the MoT fungus could survive on one of these alternative crops, thus completely negating any benefit of the “wheat holiday.” The authors point out that the fungus has been reported to survive on maize.

A short-term solution?

In both studies, the authors discourage a “wheat holiday” policy as a holistic solution. However, they leave room for governments to pursue it on an interim and short-term basis.

In the case of Bangladesh, the researchers assert that a “wheat holiday” would increase the country’s reliance on imports, especially in the face of rapidly increasing wheat demand and urbanization. A policy that results in complete dependence on wheat imports, they point out, may not be politically attractive or feasible. Also, the policy would be logistically challenging to implement. Finally, since the disease can potentially survive on other host plants, such as weeds and maize—it may not even work in the long run.

In the interim, the government of Bangladesh may still need to rely on the “wheat holiday” policy in the severely blast-affected districts. In these areas, they should encourage farmers to cultivate lentils, onions and garlic. In addition, in the short term, the government should make generic fungicides widely available at affordable prices and provide an early warning system as well as adequate information to help farmers effectively combat the disease and minimize its consequences.

In the case of West Bengal, India, similar implications apply – although the authors conclude that the “wheat holiday” policy could only work if Bangladesh has the same policy in its blast-affected border districts, which would involve potentially difficult and costly inter-country collaboration, coordination and logistics.

Actions for long-term success

The CIMMYT researchers urge the governments of India and Bangladesh, their counterparts in the region and international stakeholders to pursue long-term solutions, including developing a convenient diagnostic tool for wheat blast surveillance and a platform for open data and science to combat the fungus.

A promising development is the blast-resistant (and zinc-enriched) wheat variety BARI Gom 33 which the Bangladesh Agricultural Research Institute (BARI) released in 2017 with support from CIMMYT.However, it will take at least three to five years before it will be available to farmers throughout Bangladesh. The authors urged international donor agencies to speed up the multiplication process of this variety.

CIMMYT scientists in both studies close with an urgent plea for international financial and technical support for collaborative research on disease epidemiology and forecasting, and the development and dissemination of new wheat blast-tolerant and resistant varieties and complementary management practices – crucial steps to ensuring food security for more than a billion people in South Asia.

Read the full articles on Averting Wheat Blast by Implementing a ‘Wheat Holiday’: In Search of Alternative Crops in West Bengal, India and Alternative use of wheat land to implement a potential wheat holiday as wheat blast control: In search of feasible crops in Bangladesh

Wheat Blast Impacts

First officially reported in Brazil in 1985, where it eventually spread to 3 million hectares in South America and became the primary reason for limited wheat production in the region, wheat blast moved to Bangladesh in 2016. There it affected nearly 15,000 hectares of land in eight districts, reducing yield by as much as 51 percent in the affected fields.

Blast is devilish: directly striking the wheat ear, it can shrivel and deform the grain in less than a week from the first symptoms, leaving farmers no time to act. There are no widely available resistant varieties, and fungicides are expensive and provide only a partial defense. The disease, caused by the fungus Magnaporthe oryzae pathotype triticum (MoT), can spread through infected seeds as well as by spores that can travel long distances in the air.

South Asia has a long tradition of wheat consumption, especially in northwest India and Pakistan, and demand has been increasing rapidly across South Asia. It is the second major staple in Bangladesh and India and the principal staple food in Pakistan. Research indicates 17 percent of wheat area in Bangladesh, India, and Pakistan — representing nearly 7 million hectares – is vulnerable to the disease, threatening the food security of more than a billion people.

CIMMYT and its partners work to mitigate wheat blast through projects supported by U.S. Agency for International Development (USAID), the Bill and Melinda Gates Foundation, the Australian Centre for International Agricultural Research (ACIAR), Indian Council for Agricultural Research (ICAR), the CGIAR Research Program on WHEAT, and the CGIAR Platform for Big Data in Agriculture.

New infographics illustrate impact of wheat blast

Wheat blast is a fast-acting and devastating fungal disease that threatens food safety and security in the Americas and South Asia.

First officially identified in Brazil in 1984, the disease is widespread in South American wheat fields, affecting as much as 3 million hectares in the early 1990s.

 In 2016, it crossed the Atlantic Ocean, and Bangladesh suffered a severe outbreak. Bangladesh released a blast-resistant wheat variety—developed with breeding lines from the International Maize and Wheat Improvement Center (CIMMYT)—in 2017, but the country and region remain extremely vulnerable.

The continued spread of blast in South Asia—where more than 100 million tons of wheat are consumed each year—could be devastating.

Researchers with the CIMMYT-led and USAID-supported Cereal Systems Initiative for South Asia (CSISA) and Climate Services for Resilient Development (CSRD) projects partner with national researchers and meteorological agencies on ways to work towards solutions to mitigate the threat of wheat blast and increase the resilience of smallholder farmers in the region. These include agronomic methods and early warning systems so farmers can prepare for and reduce the impact of wheat blast.

This series of infographics shows how wheat blast spreads, its potential effect on wheat production in South Asia and ways farmers can manage it.   

This work is funded by the U.S. Agency for International Development (USAID) and the Bill & Melinda Gates Foundation). CSISA partners include CIMMYT, the International Food Policy Research Institute (IFPRI), and the International Rice Research Institute (IRRI).

CIMMYT and its partners work to mitigate wheat blast through projects supported by U.S. Agency for International Development (USAID), the Bill and Melinda Gates Foundation, the Australian Centre for International Agricultural Research (ACIAR), Indian Council for Agricultural Research (ICAR), CGIAR Research Program on WHEAT, and the CGIAR Platform for Big Data in Agriculture.

See more on wheat blast here: https://www.cimmyt.org/wheat-blast/

Call for action on wheat blast threat in South Asia

This blast-infected wheat spike contains no grain, only chaff. Photo: CIMMYT files

By Gideon Kruseman and Mike Listman

A spatial mapping and ex ante study regarding the risk and potential spread in South Asia of wheat blast, a mysterious and deadly disease from the Americas that unexpectedly infected wheat in southwestern Bangladesh in 2016, identified 7 million hectares of wheat cropping areas in Bangladesh, India, and Pakistan whose agro-climatic conditions resemble those of the Bangladesh outbreak zone.

The study shows that, under a conservative scenario of 5-10% wheat blast production damage in a single season in those areas, wheat grain losses would amount to from 0.89 to 1.77 million tons, worth between $180 and $350 million. This would strain the region’s already fragile food security and force up wheat imports and prices, according to Khondoker Abdul Mottaleb, first author of the study.

“Climate change and related changes in weather patterns, together with continuing globalization, expose wheat crops to increased risks from pathogens that are sometimes transported over long distances,” said Mottaleb.

Foresight research at the International Maize and Wheat Improvement Center (CIMMYT) has focused on new diseases and pests that have emerged or spread in recent decades, threatening global food safety and security. For wheat these include Ug99 and other new strains of stem rust, the movement of stripe rust into new areas, and the sudden appearance in Bangladesh of wheat blast, which had previously been limited to South America.

“As early as 2011, CIMMYT researchers had warned that wheat blast could spread to new areas, including South Asia,” said Kai Sonder, who manages CIMMYT’s geographic information systems lab and was a co-author on the current study, referring to a 2011 note published by the American Pathological Society. “Now that forecast has come true.”

CIMMYT has played a pivotal role in global efforts to study and control blast, with funding from the Australian Center for International Agricultural Research (ACIAR), the CGIAR Research Program on Wheat (WHEAT), the Indian Council of Agriculture Research (ICAR), and the United States Agency for International Development (USAID).

This has included the release by Bangladesh of the first blast resistant, biofortified wheat variety in 2017, using a CIMMYT wheat line, and numerous training events on blast for South Asia researchers.

Click here to read the article in PLOS-One: “Threat of wheat blast to South Asia’s food security: An ex-ante analysis.

 

 

 

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.

First blast resistant, biofortified wheat variety released in Bangladesh

Scientists inspecting plants for wheat blast infection, at a workshop in Bangladesh in February 2017. Photo: Chris Knight-Cornell.

DHAKA, Bangladesh (CIMMYT) — As wheat farmers in Bangladesh struggle to recover from a 2016 outbreak of a mysterious disease called “wheat blast,” the country’s National Seed Board (NSB) released a new, high-yielding, blast-resistant wheat variety, according to a communication from the Wheat Research Centre (WRC) in Bangladesh.

Called “BARI Gom 33,” the variety was developed by WRC using a breeding line from the International Maize and Wheat Improvement Center (CIMMYT), a Mexico-based organization that has collaborated with Bangladeshi research organizations for decades, according to Naresh C. Deb Barma, Director of WRC, who said the variety had passed extensive field and laboratory testing. “Gom” means “wheat grain” in Bangla, the Bengali language used in Bangladesh.

“This represents an incredibly rapid response to blast, which struck in a surprise outbreak on 15,000 hectares of wheat in southwestern Bangladesh just last year, devastating the crop and greatly affecting farmers’ food security and livelihoods, not to mention their confidence in sowing wheat,” Barma said.

Caused by the fungus Magnaporthe oryzae pathotype triticum, wheat blast was first identified in Brazil in 1985 and has constrained wheat farming in South America for decades. Little is known about the genetics or interactions of the fungus with wheat or other hosts. Few resistant varieties have been released in Brazil, Bolivia and Paraguay, the countries most affected by wheat blast.

The Bangladesh outbreak was its first appearance in South Asia, a region where rice-wheat cropping rotations cover 13 million hectares and over a billion inhabitants eat wheat as main staple.

Many blast fungal strains are impervious to fungicides, according to Pawan Singh, a CIMMYT wheat pathologist. “The Bangladesh variant is still sensitive to fungicides, but this may not last forever, so we’re rushing to develop and spread new, blast-resistant wheat varieties for South Asia,” Singh explained.

The urgent global response to blast received a big boost in June from the Australian Centre for International Agricultural Research (ACIAR), which funded an initial four-year research project to breed blast resistant wheat varieties and the Indian Council of Agricultural Research (ICAR), which also provided grant to kick-start the work in South Asia. Led by CIMMYT, the initiative involves researchers from nearly a dozen institutions worldwide.

Chemical controls are costly and potentially harmful to human and environmental health, so protecting crops like wheat with inherent resistance is the smart alternative, but resistance must be genetically complex, combining several genes, to withstand new mutations of the pathogen over time.

Key partners in the new project are the agricultural research organizations of Bangladesh, including the Bangladesh Agricultural Research Institute (BARI), and the Instituto Nacional de Innovación Agropecuaria y Forestal in Bolivia, which will assist with large-scale field experiments to select wheat lines under artificial and natural infections of wheat blast.

Other partners include national and provincial research organizations in India, Nepal and Pakistan, as well as Kansas State University (KSU) and the U.S. Department of Agriculture-Agricultural Research Services (USDA-ARS). The U.S. Agency for International Agricultural Development (USAID) has also supported efforts to kick-start blast control measures, partnerships and upscaling the breeding, testing and seed multiplication of new, high-yielding, disease resistant varieties through its Feed the Future project.

BARI Gom 33 was tested for resistance to wheat blast in field trials in Bolivia and Bangladesh and in greenhouse tests by the USDA-ARS laboratory at Fort Detrick, Maryland. International partnerships are critical for a fast response to wheat blast, according to Hans-Joachim Braun, director of CIMMYT’s Global Wheat Program.

“Worldwide, we’re in the middle of efforts that include blast surveillance and forecasting, studies on the pathogen’s genetics and biology, integrated disease management and seed systems, as well as raising awareness about the disease and training for researchers, extension workers, and farmers,” said Braun.

With over 160 million people, Bangladesh is among the world’s most densely populated countries. Wheat is Bangladesh’s second most important staple food, after rice. The country grows more than 1.3 million tons each year but consumes 4.5 million tons, meaning that imports whose costs exceed $0.7 billion each year comprise more than two-thirds of domestic wheat grain use.

WRC will produce tons of breeder’s seed of BARI Gom 33 each year. This will be used by the Bangladesh Agricultural Development Corporation (BADC) and diverse non-governmental organizations and private companies to produce certified seed for farmers.

“This year WRC will provide seed to BADC for multiplication and the Department of Agricultural Extension will establish on-farm demonstrations of the new variety in blast prone districts during 2017-18,” said Barma.

As an added benefit for the nutrition of wheat consuming households, BARI Gom 33 grain features 30 percent higher levels of zinc than conventional wheat. Zinc is a critical micronutrient missing in the diets of many of the poor throughout South Asia and whose lack particularly harms the health of pregnant women and children under 5 years old.

With funding from HarvestPlus and the CGIAR Research Program on Agriculture for Nutrition, CIMMYT is leading global efforts to breed biofortified wheat with better agronomic and nutritional quality traits. The wheat line used in BARI Gom 33 was developed at CIMMYT, Mexico, through traditional cross-breeding and shared with Bangladesh and other cooperators in South Asia through the Center’s International Wheat Improvement Network, which celebrates 50 years in 2018.

Stable window 1 and 2 (W1W2) funding from CGIAR enabled CIMMYT and partners to react quickly and screen breeding lines in Bolivia, as well as working with KSU to identify sources of wheat blast resistance. The following W1 funders have made wheat blast resistance breeding possible: Australia, the Bill & Melinda Gates Foundation, Canada, France, India, Japan, Korea, New Zeland, Norway, Sweden, Switzerland, the United Kingdom and the World Bank. The following funders also contributed vital W2 funding: Australia, China, the United Kingdom (DFID) and USAID.

Asian scientists join cross-continental training to restrain wheat blast disease

Gary Peterson (center), explaining wheat blast screening to trainees inside the USDA-ARS Level-3 Biosafety Containment facility. Photo: CIMMYT archives

With backing from leading international donors and scientists, nine South Asia wheat researchers recently visited the Americas for training on measures to control a deadly and mysterious South American wheat disease that appeared suddenly on their doorstep in 2016.

Known as “wheat blast,” the disease results from a fungus that infects the wheat spikes in the field, turning the grain to inedible chaff. First sighted in Brazil in the mid-1980s, blast has affected up to 3 million hectares in South America and held back the region’s wheat crop expansion for decades.

In 2016, a surprise outbreak in seven districts of Bangladesh blighted wheat harvests on some 15,000 hectares and announced blast’s likely spread throughout South Asia, a region where rice-wheat cropping rotations cover 13 million hectares and nearly a billion inhabitants eat wheat.

“Most commercially grown wheat in South Asia is susceptible to blast,” said Pawan Singh, head of wheat pathology at the International Maize and Wheat Improvement Center (CIMMYT), an organization whose breeding lines are used by public research programs and seed companies in over 100 countries. “The disease poses a grave threat to food and income security in the region and yet is new and unknown to most breeders, pathologists and agronomists there.”

As part of an urgent global response to blast and to acquaint South Asian scientists with techniques to identify and describe the pathogen and help develop resistant varieties, Singh organized a two-week workshop in July. The event drew wheat scientists from Bangladesh, India, Nepal and Mexico, taking them from U.S. greenhouses and labs to fields in Bolivia, where experimental wheat lines are grown under actual blast infections to test for resistance.

The training began at the U.S. Department of Agriculture-Agricultural Research Service (USDA-ARS) Foreign Disease-Weed Science Research facility at Fort Detrick, Maryland, where participants learned about molecular marker diagnosis of the causal fungus Magnaporthe oryzae pathotype triticum (MoT). Sessions also covered greenhouse screening for blast resistance and blast research conducted at Kansas State University. Inside Level-3 Biosafety Containment greenhouses from which no spore can escape, participants observed specialized plant inoculation and disease evaluation practices.

The group then traveled to Bolivia, where researchers have been fighting wheat blast for decades and had valuable experience to share with the colleagues from South Asia.

“In Bolivia, workshop participants performed hands-on disease evaluation and selection in the field—an experience quite distinct from the precise lab and greenhouse practicums,” said Singh, describing the groups time at the Cooperativa Agropecuaria Integral Colonias Okinawa (CAICO), Bolivia, experiment station.

Other stops in Bolivia included the stations of the Instituto Nacional de Innovación Agropecuaria y Forestal (INIAF), Asociación de Productores de Oleaginosas y Trigo (ANAPO), Centro de Investigación Agrícola Tropical (CIAT), and a blast-screening nursery in Quirusillas operated by INIAF-CIMMYT.

“Scientists in South Asia have little or no experience with blast disease, which mainly attacks the wheat spike and is completely different from the leaf diseases we normally encounter,” said Prem Lal Kashyap, a scientist at the Indian Institute of Wheat and Barley Research (IIWBR) of the Indian Council of Agricultural Research (ICAR). “To score a disease like blast in the field, you need to evaluate each spike and check individual spikelets, which is painstaking and labor-intensive, but only thus can you assess the intensity of disease pressure and identify any plants that potentially carry genes for resistance.”

After the U.S.A. and Bolivia, the South Asia scientists took part in a two-week pathology module of an ongoing advanced wheat improvement course at CIMMYT’s headquarters and research stations in Mexico, covering topics such as the epidemiology and characterization of fungal pathogens and screening for resistance to common wheat diseases.

The knowledge gained will allow participants to refine screening methods in South Asia and maintain communication with the blast experts they met in the Americas, according to Carolina St. Pierre who co-ordinates the precision field-based phenotyping platforms of the CGIAR Research Program on Wheat.

“They can now also raise awareness back home concerning the threat of blast and alert farmers, who may then take preventative and remedial actions,” Singh added. “The Bangladesh Ministry of Agriculture has already formed a task force through the Bangladesh Agricultural Research Council (BARC) to help develop and distribute blast resistant cultivars and pursue integrated agronomic control measures.”

The latest course follows on from a hands-on training course in February 2017 at the Wheat Research Center (WRC) of the Bangladesh Agricultural Research Institute (BARI), Dinajpur, in collaboration with CIMMYT, Cornell University, and Kansas State University.

Participants in the July course received training from a truly international array of instructors, including Kerry Pedley and Gary Peterson, of USDA-ARS, and Christian Cruz, of Kansas State University; Felix Marza, of Bolivia’s Instituto Nacional de Innovación Agropecuaria y Forestal (INIAF); Pawan Singh and Carolina St. Pierre, of CIMMYT; Diego Baldelomar, of ANAPO; and Edgar Guzmán, of CIAT-Bolivia.

Funding for the July event came from the Bangladesh Agricultural Research Institute (BARI), the Indian Council of Agricultural Research (ICAR), CIMMYT, the United States Agency for International Development (USAID) and the Bill & Melinda Gates Foundation (through the Cereal Systems Initiative for South Asia), the Australian Centre for International Agricultural Research (ACIAR), and the CGIAR Research Program on Wheat.