Posts Tagged ‘Borlaug Global Rust Initiative’

Smarter deployment of disease-resistance genes critical for safeguarding world’s food supplies

This story by Matt Hayes was originally posted on the Borlaug Global Rust Initiative website.

Maricelis Acevedo inspects wheat samples with Murugasamy Sivasamy at the Indian Agricultural Research Institute, Regional station, Wellington. Photo: Matt Hayes / Cornell

In the worst years of the rust disease epidemic that decimated North American wheat fields in the 1950s, fungal spores riding wind currents across the continent reached into the sextillions — that’s a number with 21 zeros.

Severe wheat disease epidemics produce staggering numbers of spores containing incredible genetic diversity — and incalculable risks to global food supplies. If fungal spores encounter even a single susceptible wheat variety, natural selection positions the pathogen to take hold and proliferate, releasing more rounds of spores and spreading its own virulence genes across entire populations.  

Wheat breeders face a daunting task trying to defend against such a relentless barrage of evolving pathogens. In the battle, scientific ingenuity confronts biological innovation: wheat varieties that contain single disease-resistant genes can be easily overrun by rapidly evolving spores.

To safeguard food supplies and ensure durable disease resistance in wheat, scientists must embrace a globally integrated strategy that deploys resistant genes in a coordinated way, according to Maricelis Acevedo, associate director of science for the Delivering Genetic Gain in Wheat (DGGW) project.

“We need to be smart about gene deployment,” Acevedo said at the All India Wheat and Barley meeting Aug. 25 in Indore, Madhya Pradesh.

“If we don’t change our mentality, we risk reliving the worst horrors of the past and the widespread hunger that results when rust diseases wipe out the wheat supply,” she said.

Acevedo cautioned that the release of susceptible or vulnerable varieties at a national level weakens wheat resistance on a global scale. Varieties with only one major effective resistance gene, which may appear adequate to withstand disease pressure in a field trial, are at increased risk to disease pressure when released into circulation. Varieties with only a single resistance gene risk tainting an otherwise effective gene for everybody and imperiling the wheat crop around the world.

Varieties with five to six disease-resistance genes make it mathematically unlikely that spores will have the genetic ability to defeat the resistance. Minnesota scientists in 1985 calculated that the probability a pathogen contains virulence to all six major genes is more than four times greater than the number of spores released in a single year in the US under stem rust epidemic levels. 

To reduce the chances of selection in pathogen populations, often caused by major genes, breeders exploit combinations of genes that may provide partial resistance to a broader number of races.

Ravi Singh gives his presentation at the All India Wheat and Barley meeting in Indore. Photo: Matt Hayes / Cornell

While only releasing varieties with stacked genes is the most prudent breeding strategy, there are factors that incentivize shortcuts, according to Acevedo. Plant breeders in some countries are often promoted based on the numbers of varieties released — not for their long-term usefulness. And, in some countries, there are political incentives to provide farmers with new varieties year after year rather than release fewer, but more durable varieties.

Teams of plant breeders employed by National Agricultural Research Systems in countries around the world develop improved crop varieties. Many wheat breeders receive lines from CIMMYT, the International Maize and Wheat Improvement Center, which national scientists then cross with local varieties to adapt to local conditions. National scientists also breed their own from existing local varieties. The process to develop and release any new variety can take up to ten years and up to 15 years to make it to farmers fields.

 “A way to make varieties more durable for resistance to rusts is to use marker-assisted introgression of multiple resistance genes using speed breeding in recent varieties or promising varietal candidates, which also possess some of the known durable adult-plant resistance genes,” said Ravi Singh, distinguished scientist and head of Global Wheat Improvement at CIMMYT. The All India Wheat and Barley meeting was co-sponsored by CIMMYT and the International Center for Agricultural Research in the Dry Areas (ICARDA).

The Borlaug Global Rust Initiative (BGRI) was established at Cornell to reduce the world’s vulnerability to stem, yellow and leaf rusts of wheat. Acevedo said the BGRI’s main impacts have resulted from scientific collaboration, commitment to pathogen monitoring, and development and deployment of rust resistant varieties. The BGRI established a Gene Stewardship Award in 2012 to encourage the release of varieties with complex and diverse disease resistance.

In 2018, the Indian Council of Agricultural Research (ICAR), in New Delhi, India, and associated institutions, received the BGRI Gene Stewardship Award in part for replacing susceptible wheat varieties with resistant varieties.

Those efforts have proven successful: on Aug. 24, in a reported delivered at the All India Wheat and Barley meeting, ICAR announced that India for the first time produced more than 100 million tons of wheat in a year.

DGGW is funded by the Bill & Melinda Gates Foundation and UK Aid by the British people.

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.