Posts Tagged ‘breeding’

Wheat-rye crosses provide control for deadly sap-sucking aphid

Pictured are Martin Kropff, CIMMYT director general (left) and Mustapha El-Bouhssini, ICARDA entomologist, in that center’s lab at Rabat, Morocco.

In an excellent example of scientific collaboration spanning borders and generations, Mustapha El-Bouhssini, entomologist at the International Centre for Agricultural Research in the Dry Areas (ICARDA), screened wheat breeding lines from the International Maize and Wheat Improvement Center (CIMMYT) under glasshouse infestations of Russian wheat aphid (Diuraphis noxia), a major global pest of wheat. At least one of the lines, which were developed through crosses of wheat with related crop and grass species, showed high levels of resistance.

Scientists at CIMMYT began research on sources of RWA resistance for wheat in the early 1990s. Good sources of resistance from rye were accessed via wide crosses that combined major portions of both crop’s chromosomes, in collaborative work led by Adam J. Lukaszewski, University of California, Riverside.

“In our experiments, we did an initial screening with one replication and then a replicated test with a Pavon line and the check,” said El-Bouhssini.

Pavon is a semi-dwarf wheat variety developed by Sanjaya Rajaram, former CIMMYT wheat director and 2014 World Food Prize laureate. The version of Pavon referred to by El-Bouhssini had been crossed with rye by Lukaszewski and entered CIMMYT’s wheat genetic resource collections; the check was a popular high-yielding variety with no resistance to Russian wheat aphid.

Pavon had been used by Lukaszewski and colleagues as a model variety for wide crosses to transfer pest and disease resistance to wheat from its distant relatives. More recently Leonardo Crespo-Herrera, CIMMYT wheat breeder, pursued this research for his doctoral studies. It was he who provided a selection of wide-cross lines to El-Bouhssini.

“Resistance to pests in wheat is a valuable trait for farmers and the environment,” said Crespo-Herrera. “It can protect yield for farmers who lack access to other control methods. For those with access to insecticides, it can minimize their use and cost, as well as negative impacts on the environment and human health.”

 

The resistant wheat line (center) is green while all others have perished under heavy infestation of Russian wheat aphid, in the ICARDA entomology lab at Rabat, Morocco.

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.

 

 

 

Global grain research and food industry experts meet to address rising malnutrition

The world’s quickly-rising population needs not only more food but healthier, more nutritious food, according to Julie Miller Jones, Professor Emerita at St. Catherine University, and Carlos Guzmán, who leads wheat quality research at CIMMYT. Photo: CIMMYT/ Mike Listman

MEXICO CITY (CIMMYT) — Malnutrition is rising again and becoming more complex, according to the director-general of the world’s leading public maize and wheat research center.

“After declining for nearly a decade to around 770 million, the number of hungry people has increased in the last two years to more than 850 million,” said Martin Kropff, director general of the International Maize and Wheat Improvement Center (CIMMYT), in the opening address of the 4th Latin American Cereals Conference.

“Those people suffer from calorie malnutrition and go to bed hungry at night, which is a terrible thing,” Kropff added. “But the diets of 2 billion persons worldwide lack essential micronutrients — Vitamin A, iron, or zinc — and this especially affects the health and development of children under 5 years old.”

Kropff noted that some 650 million people are obese, and the number is increasing. “All these nutrition issues are interconnected, and are driven by rising population, global conflicts, and — for obesity — increasing prosperity, in developed and emerging economies.”

“The solution? Good, healthy diets,” said Kropff, “which in turn depend on having enough food available, but also diverse crops and food types and consumer education on healthy eating.”

Held in Mexico City during 11-14 March and co-organized by CIMMYT and the International Association for Cereal Science and Technology (ICC), the 4th Latin American Cereals Conference has drawn more than 220 participants from 46 countries, including professionals in agricultural science and production, the food industry, regulatory agencies, and trade associations.

“We are dedicated to spreading information about cereal science and technology, processing, and the health benefits of cereals,” said Hamit Köksel, president of the ICC and professor at Hacettepe University, Turkey, to open the event. “Regarding the latter, we should increase our whole grain consumption.”

Köksel added that ICC has more than 10,000 subscribers in 85 countries.

New zinc biofortified maize variety BIO-MZN01, recently released in Colombia. Photo: CIMMYT archives

New zinc biofortified maize variety BIO-MZN01,
recently released in Colombia. Photo: CIMMYT archives

Breeding micronutrient-dense cereals

One way to improve the nutrition and health of the poor who cannot afford dietary supplements or diverse foods is through “biofortification” of the staple crops that comprise much of their diets.

Drawing upon landraces and diverse other sources in maize and wheat’s genetic pools and applying innovative breeding, CIMMYT has developed high-yielding maize and wheat lines and varieties that feature enhanced levels of grain zinc and are being used in breeding programs worldwide.

“In the last four years, the national research programs of Bangladesh, India, and Pakistan have released six zinc-biofortified wheat varieties derived from CIMMYT research,” said Hans Braun, director of the center’s global wheat program. “Zinc-Shakthi, an early-maturing wheat variety released in India in 2014 whose grain features 40 percent more zinc than conventional varieties, is already grown by more than 50,000 smallholder farmers in the Northeastern Gangetic Plains of India.”

CIMMYT is focusing on enhancing the levels of provitamin A and zinc in the maize germplasm adapted to sub-Saharan Africa, Asia, and Latin America. Improved quality protein maize (QPM) varieties, whose grain features enhanced levels of two essential amino acids, lysine and tryptophan,  is another major biofortified maize that is grown worldwide, according to Prasanna Boddupalli, director of CIMMYT’s global maize program.

“Quality protein maize varieties are grown by farmers on 1.2 million hectares in Africa, Asia, and Latin America,” said Prasanna, in his presentation, adding that provitamin-A-enriched maize varieties have also been released in several countries in Africa, besides Asia.

A major partner in these efforts is HarvestPlus, part of the CGIAR Research Program on Agriculture for Nutrition and Health (A4NH), which supports the development and promotion of the biofortified crop varieties and related research.

“Biofortified crops have been released in 60 countries,” said Wolfgang Pfeiffer, HarvestPlus global director for product development and commercialization, speaking at the conference. “The pressing need now is to ‘mainstream’ biofortification, making it a standard component of breeding programs and food systems.”

Whole grains are good for you

A central issue on the conference agenda is promoting awareness about the importance of healthy diets and the role of whole grains.

“Participants will discuss the large body of published studies showing that whole grain foods, including processed ones, are associated with a significantly reduced risk of chronic diseases and obesity,” said Carlos Guzmán, who leads wheat quality research at CIMMYT and helped organize the conference. “There is a global movement to promote the consumption of whole grains and the food industry worldwide is responding to rising consumer demand for whole grain products.”

Guzmán also thanked the conference sponsors: Bimbo, Bastak Instruments, Brabender, Foss, Chopin Technologies, Perten, Stable Micro Systems Scientific Instruments, Cereal Partners Worldwide Nestlé and General Mills, Stern Ingredients-Mexico, World Grain, the CGIAR Research Program on Wheat, and Megazyme.

Scientists confirm value of whole grains and wheat for nutrition and health

15 February 2018

New study squashes claims that gluten and wheat are bad for human health. Photo: CIMMYT/ Mike Listman

Based on a recent, special compilation of 12 reports published in the scientific journal Cereal Foods World during 2014-2017, eating whole grains is actually beneficial for brain health and associated with reduced risk of diverse types of cancer, coronary disease, diabetes, hypertension, obesity and overall mortality.EL BATAN, Mexico (CIMMYT) – A new, exhaustive review of recent scientific studies on cereal grains and health has shown that gluten- or wheat-free diets are not inherently healthier for the general populace and may actually put individuals at risk of dietary deficiencies.

“Clear and solid data show that eating whole-grain wheat products as part of a balanced diet improves health and can help maintain a healthy body weight, apart from the 1 percent of people who suffer from celiac disease and another 2 to 3 percent who are sensitive to wheat,” said Carlos Guzmán, wheat nutrition and quality specialist at the Mexico-based International Maize and Wheat Improvement Center (CIMMYT), which produced the compilation.

Guzmán said wheat and other grains are inexpensive sources of energy that also provide protein, digestible fiber, minerals, vitamins, and other beneficial phytochemicals.

“Among wheat’s greatest benefits, according to the research, is fiber from the bran and other grain parts,” he explained. “Diets in industrialized countries are generally deficient in such fiber, which helps to regulate digestion and promote the growth of beneficial gut bacteria.”

Guzmán and hundreds of other grain quality and health specialists will meet for the 4th Latin American Cereals Conference and the 13th International Gluten Workshop, organized jointly by CIMMYT and the International Association for Cereal Science and Technology (ICC) in Mexico City from 11 to 17 March 2018.

Contributing to humankind’s development for the last 10,000 years, wheat is cultivated on some 220 million hectares (539 million acres) worldwide. The crop accounts for a fifth of the world’s food and is the main source of protein in many developing and developed countries, and second only to rice as a source of calories globally. In the many countries where milling flours are fortified, wheat-based foods provide necessary levels of essential micronutrients such as iron, zinc, folic acid and vitamin A.

Inhabitants in developing and industrialized countries are experiencing higher incidences of diabetes, allergies, inflammatory bowel disorder, and obesity. A profitable industry has developed around gluten- and wheat-free food products, which the popular press has promoted as beneficial for addressing such disorders. But much scientific evidence contradicts popular writings about these food products.

“Much of the anti-grain messaging comes from publications produced by supposed ‘specialists’ who are not nutritionists, and are often built on faulty premises.” according to Julie Miller Jones, Distinguished Scholar and Professor Emerita at St. Catherine University, U.S.A., and a key contributor to the review studies in the compilation.

“Causes of obesity and chronic disease are complex, and it is not only simplistic but erroneous to name a single food group as the cause or the cure for these problems,” Miller Jones explained.  “We do know that we consume large portions, too many calories, and too few fruits, vegetables, or whole grains.  Instead today’s lifestyles encourage consumption of many high calorie foods and beverages that contain few nutrients. Then the risks of poor diets are often amplified by our sedentary lifestyles.”

CIMMYT scientists are concerned that the negative portrayal of wheat to promote the lucrative gluten-free fad diet industry will discourage low-income families from consuming the grain as part of an affordable and healthy diet, particularly in areas where there are few low-cost alternatives.

Consumer Reports magazine reported in January 2015 that sales of “gluten-free” products soared 63 percent between 2012 and 2015, with almost 4,600 products introduced in 2014 alone. Retail sales of gluten-free foods in the United States were estimated at $12.2 billion in 2014 and by 2020 the market is projected to be valued at $23.9 billion, Statistica reports.

However, wheat biofortified through breeding or fortified during milling with zinc and iron can play a vital role in diets in areas where “hidden hunger” is a concern and where nutritional options are unaffordable or unavailable. About 2 billion people worldwide suffer from hidden hunger, which is characterized by iron-deficiency anemia, vitamin A and zinc deficiency.

The compilation draws on more than 1,500 peer-reviewed studies regarding the dietary and health effects of eating cereals and wheat-based foods.

CIMMYT specialists also worry that misinformation about wheat might affect investments in vital research to sustain wheat production increases of at least 60 percent by 2050, the output required to keep pace with rising population and demand, according to Hans Braun, director of the center’s global wheat program.

“Climate change is already constraining wheat production in regions such as South Asia, where more than 500 million inhabitants eat wheat-based foods,” Braun said. “Worldwide, the crop is threatened by deadly pest and disease strains, water shortages, and depleted soils.”

“As we have seen in 2008, 2011, and just recently in Tunisia and Sudan, grain shortages or price hikes in bread can lead to social unrest,” Braun added. “The international community needs to speed efforts to develop and share high-yielding, climate-resilient, and disease-resistant wheat varieties that also meet humanity’s varied nutritional demands.”

The compilation was produced with special permission from AACC International.

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.

Emergency seed fuels quick farm recovery in drought-affected Ethiopia

In response to Ethiopia’s worst drought in 50 years and the country’s critical shortage of maize and wheat seed for sowing in 2016, Ethiopian organizations, seed producers, and the International Maize and Wheat Improvement Center (CIMMYT) partnered to deliver over 3,400 tons of high quality seed to farmers, which was sown on more than 100,300 hectares.

“This effort helped rescue the food security and livelihoods of more than 271,000 rural households and 1.6 million individuals in Ethiopia’s Amhara, Oromia, Tigray, and SNNP regions, and strengthened seed systems to address future climate, disease, and pest crises,” said Bekele Abeyo, CIMMYT wheat scientist who led the seed relief initiative.

Funded by the U.S. Agency for International Development (USAID) and Office of Foreign Disaster Assistance (OFDA) of the U.S. Ethiopia mission, seed relief complemented international and national food aid, helping farm families to quickly grow crops after several seasons of erratic or failed rains in Ethiopia and the catastrophic 2015-16 El Niño droughts. At that time, more than 10 million people struggled to find food, as eastern Ethiopia faced crop losses from 50 to 90 percent of expected yields.

“We went three years without rain,” says farmer Usman Kadir, whose 1.5-hectare homestead in Wanjo Bebele village, Halaba Special Woreda, supports a household of 11 persons. “We were able to eat thanks to emergency food programs.” In 2017, Kadir used emergency maize seed to sow half a hectare and harvested 3 tons, getting his farm back on its feet. “If more new improved varieties come, we want to work with you and expand our farming operation.”

Photo: Atlabtamu/CIMMYT.

Usman Kadir. Photos here and above: CIMMYT/A.Habtamu.

Wheat and maize: Mainstays of food security

Agriculture provides 42 percent of Ethiopia’s GDP, 77 percent of employment, and 84 percent of exports. Subsistence, smallholder farmers predominate, making their living from less than two hectares of land. Wheat and maize are the most important crops for food security; they are also at the center of Ethiopia’s increasingly vibrant agricultural output markets and have been the focus in recent years of public investment to raise national production.

Maize and wheat production in Ethiopia depends on rainfall, making the unpredictable weather patterns caused by climate change exceptionally detrimental here. Various studies predict an average 30 percent reduction in farm incomes due to climate change impacts, including greater extremes in temperatures and rainfall (floods, droughts) and the emergence of new pest and disease strains. Research shows that reduced precipitation is already holding back wheat yields.

To address this, experts identified maize and wheat varieties suitable for drought-affected areas and highly resistant to prevalent crop diseases. Of the maize varieties, some 10 percent were quality protein maize, which carries enhanced levels of key amino acids for protein synthesis in humans.

“This effort also provided training for district and zonal development agents in crop protection, agronomy, drought mitigation practices, and seed systems,” said Abeyo. “Finally, five women seed producer associations received wheat seed threshers and a large union of farmer seed producer cooperatives received a maize sheller through the initiative. This equipment will greatly expedite their operations and contribute to the expanded and more reliable access of farmers to affordable, quality seed in the future.”

Partners and contributors

Emergency relief seed was sourced through diverse CIMMYT partnerships, including producers in the USAID-funded “Drought Tolerant Maize for Seed Scaling Project” (DTMASS) and “Wheat Seed Scaling Initiative.” Stakeholders included the Ministry of Agriculture and Natural Resources (MoANR), the Bureau of Agriculture and Natural Resources (BoANR), public and private seed companies/enterprises, farmer cooperative unions, federal and regional research institutes, and non-government organizations working in target areas. With funding from the Bill & Melinda Gates FoundationEthiopia’s Agricultural Transformation Agency (ATA) helped deliver seed to drought-affected districts and jointly organized training and workshops.

Click here to read a full report on the emergency seed relief initiative.