Yemen identified as “stepping stone” to wheat stem rust’s global spread

September 26, 2017

A new study reports Yemen as a particular tipping point for stem rust’s global spread. Photo: Petr Kosina/ CIMMYT

 

EL BATAN, Mexico (CIMMYT) – New research reveals the most likely routes for the spread of new wheat stem rust strains, identifying Yemen as a critical transmission area for the disease’s global spread.

In the Nature Plants study, scientists from the International Maize and Wheat Improvement Center (CIMMYT), the University of Cambridge and the UK Met Office adapted modeling systems previously used to forecast ash dispersal from erupting volcanoes and radiation from nuclear accidents to predict the spread of stem rust strains.

The study quantifies for the first time the circumstances – routes, timings and outbreak sizes –  under which dangerous strains of stem rust pose a threat, detailing potential scenarios of the disease spreading from Africa through the Middle East and beyond.

Yemen is highlighted as a particular tipping point for stem rust’s global spread, with one scenario estimating a 30 percent chance for transmission to occur in Pakistan or India – home to some of the world’s most critical “breadbasket” regions – if the disease spreads to eastern Yemen.

“From our work, we now believe that if we start to see Ug99 or other new wheat rust strains take hold in Yemen in early spring then action must be taken immediately to mitigate the risk of further spread,” according to the study’s senior author Chris Gilligan, professor at Cambridge’s Department of Plant Sciences.

However, the researchers found that the airborne transmission of the disease from East Africa directly to South Asia is highly unlikely, with transmission events possible only on less than one day a year.

The modelling framework created in the study can also be used to analyze any potential new disease strains that might emerge in other geographic areas. The study’s researchers are currently developing an Early Warning System to forecast rust risk in Ethiopia, East Africa’s largest wheat producing country.

Read the full study “Quantifying airborne dispersal routes of pathogens over continents to safeguard global wheat supply” here.

 

Learn more about wheat stem rust and its impact on food security below:

Likely scenarios for global spread of devastating crop disease

CIMMYT scientist cautions against new threats from wheat rust diseases

RustTracker.org | A Global Wheat Rust Monitoring System

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.

2016 ICARDA annual report–Enhancing resilience, helping dryland communities to thrive

The hottest on record, 2016 also marked another year that ICARDA has been on the frontlines of agricultural sustainability and innovation. The 2016 annual report highlights the organization’s efforts to provide farmers throughout the drylands with the latest tools, resources, and training to ensure that their livelihoods — and food security — are resilient to the increasing onslaught of climate change.

Click here to view or download a copy of the full report.

Stem rust in Western Siberia

Prof . Vladimir Shaminin (Omsk Agrarian State University) inspecting wheat plots at Omsk Agrarian State University with Dr Alexey Morgunov (CIMMYT) and Prof. Mogens Hovmøller (GRRC, Aarhus University).

An Aug 2017 field trip organized by Alexey Morgunov (CIMMYT-Turkey) to the Omsk, Novosibirsk and the Altai Krai regions of Western Siberia, Russian Federation, with the Global Rust Reference Center and Aarhus University, Denmark, aimed to get more information on 2015-16 stem rust outbreaks that affected millions of hectares in the region (Shamanin et al. 2016).

With approximately 7 million hectares of short season, high-latitude spring wheat and increasing areas of winter wheat and some durum wheat, the region is an extremely important wheat production area.

The visit highlighted the importance of wheat in this region and the strength of the research programs, but also the vulnerability of grown varieties to stem rust.

Significant changes appear to have occurred in recent years, making stem rust an emerging disease of economic concern. Further research is urgently needed, both to understand the pathogen dynamics and to increase farmers’ use of resistant varieties.

Click here to read the full blog on the Global Rust Reference Center web page.

On-line: The 2016 WHEAT annual report

The challenge for WHEAT is no less than to raise the productivity, affordability and quality of wheat and wheat-based foods for 2.5 billion resource-poor consumers in 89 countries today, as well as meeting rising demand from a world population expected to surpass 9 billion by mid-century.

Click here to see how 2016 activities and advances in science and partnerships are empowering farmers and catalyzing wheat value chains, amid political instability, fragile food markets and warmer and erratic weather.

Australia funds worldwide project to restrain wheat blast disease

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

EL BATAN, Mexico (July 1, 2017) — The urgent global response to wheat blast, a little understood fungal disease that appeared suddenly and blighted wheat crops in Bangladesh in 2016, has received a big boost from the Australian Centre for International Agricultural Research (ACIAR), which is funding an initial four-year research project to breed blast resistant wheat varieties.

The wheat blast pathogen, which can move on air currents or ride infected grain, is likely to spread soon throughout South Asia, a region where rice-wheat cropping rotations cover 13 million hectares and nearly a billion inhabitants eat wheat.

Under the initiative led by the Mexico-based International Maize and Wheat Improvement Center (CIMMYT), researchers from nearly a dozen institutions worldwide will join forces to develop high-yielding varieties with resistance to blast, reducing the risk of catastrophic crop losses.

“This research project aims to identify sources of resistance, characterize the resistance genes, and develop DNA markers to create resistant, locally-adapted wheat varieties and make them available to farmers,” said Pawan Singh, head of wheat pathology at CIMMYT, an organization whose breeding lines are used by public research programs and seed companies in over 100 countries. “The work could not be more critical, given the likelihood of blast’s spread and its deadly virulence for wheat varieties worldwide.”

Caused by the fungus Magnaporthe oryzae pathotype Triticum (MoT), wheat blast was first identified in Brazil in 1985 and has threatened and constrained wheat farming in South America for decades.

Fungicides offer only partial control of blast, according to N.C.D. Barma, director at Bangladesh’s Wheat Research Centre (WRC). “Under the right conditions, the fungus can develop with lightning speed, blanching and withering the grain,” Barma said. “By that time the farmer’s losses are near total.”

Wheat experts and government officials in Bangladesh, in collaboration with CIMMYT, sounded the alarm last year, when a surprise blast outbreak struck 15,000 hectares of wheat fields near the country’s border with India.

Farmers in Pakistan benefit from new zinc-enriched high-yielding wheat

Hans-Joachim Braun (left, white shirt), director of the global wheat program at CIMMYT, Maqsood Qamar (center), wheat breeder at Pakistan’s National Agricultural Research Center, Islamabad, and Muhammad Imtiaz (right), CIMMYT wheat improvement specialist and Pakistan country representative, discussing seed production of Zincol. Photo: Kashif Syed/CIMMYT.

By Mike Listman/CIMMYT

ISLAMABAD, Pakistan (June 30, 2017) – Farmers in Pakistan are eagerly adopting a nutrient-enhanced wheat variety offering improved food security, higher incomes, health benefits and a delicious taste.

Known as Zincol and released to farmers in 2016, the variety yields harvests as high as other widely grown wheat varieties, but its grain contains 20 percent more zinc, a critical micronutrient missing in the diets of many poor people in South Asia.

Due to these benefits and its delicious taste, Zincol was one of the top choices among farmers testing 12 new wheat varieties in 2016.

“I would eat twice as many chappatis of Zincol as of other wheat varieties,” said Munib Khan, a farmer in Gujar Khan, Rawalpindi District, Punjab Province, Pakistan, referring to its delicious flavor.

Khan has been growing Zincol since its release. In 2017, he planted a large portion of his wheat fields with the seed, as did members of the Gujar Khan Seed Producer Group to which he belongs.

The group is one of 21 seed producer associations established to grow quality seed of new wheat varieties with assistance from the country’s National Rural Support Program (NRSP) in remote areas of Pakistan. The support program is a key partner in the Pakistan Agricultural Innovation Program (AIP), led by the International Maize and Wheat Improvement Center (CIMMYT) and funded by the U.S. Agency for International Development.

“Over the 2016 and 2017 cropping seasons, 400 tons of seed of Zincol has been shared with farmers, seed companies and promotional partners,” said Imtiaz Muhammad, CIMMYT country representative in Pakistan and a wheat improvement specialist.

ICARDA researchers receive Olam Prize for innovation in food security

MONTPELLIER, France (June 5, 2017) – The 2017 Olam Prize for Innovation in Food Security was awarded to the “Adapting durum wheat varieties to the Senegal Basin for food security” project led by Filippo Maria Youssef Bassi, durum wheat breeder at the International Center for Agricultural Research in the Dry Area (ICARDA).

Moving zinc-enriched wheat into the mainstream

By Matthew O’Leary/CIMMYT

EL BATAN, Mexico (May 30,2017)– In an effort to stamp out hidden hunger, scientists are calling for support to make zinc-biofortification a core trait in the world’s largest wheat breeding program.

At least 2 billion people around the world suffer from micronutrient deficiency, or hidden hunger, which is characterized by iron-deficiency anemia, vitamin A and zinc deficiency.

Zinc deficiency remains a crucial health issue in sub-Saharan Africa and South Asia. As a key nutrient in red meat, zinc deficiency is prevalent in areas of high cereal and low animal food consumption.

Nitrogen-efficient crops on the horizon: Can we grow more with fewer emissions?

By Mike Listman/CIMMYT

EL BATAN, Mexico (May 17, 2017) – Through a natural, affordable alternative to farmers’ heavy use of nitrogen fertilizers, science now offers an option to boost crop productivity and dramatically reduce greenhouse gas emissions, according to the authors of a report that will appear this week in the journal Plant Science.

The new study describes certain plants that possess a trait known as biological nitrification inhibition (BNI), by which they suppress the loss of nitrogen (N) from the soil and improve the efficiency of its uptake and use by themselves and other plants.

The authors, who form part of a new BNI research consortium, propose transferring the BNI trait from those plants to critical food and feed crops, such as wheat, sorghum and Brachiaria range grasses.

“Nearly a fifth of the world’s fertilizer, for example, is deployed each year to grow wheat and the crop only uses about 30 percent of the nitrogen applied,” according to Guntur Subbarao, a researcher with Japan’s International Research Center for Agricultural Sciences (JIRCAS) and lead author of the study.