CIMMYT E-News, vol 4 no. 3, March 2007

Solving a major disease problem in durum wheat was not enough to satisfy farmers. They need and will get quality too.

Karim Ammar, a durum wheat breeder with CIMMYT, is proud of his new wheat lines growing green and disease-free this season in the Yaqui valley of northern Mexico. Even with the efficiency of a shuttle system between the Yaqui valley and the highland research station at Toluca, Mexico which allows wheat breeders to plant and select wheat twice a year, it still takes six years to get to where Karim is now.

“Between preliminary yield trials and elite yield trials we’ve got about 2500 lines and they are all resistant to leaf rust,” he says.

This is good news for the durum wheat farmers of the world. Durum wheat is the kind used for pasta, couscous and semolina. Today, 85% of spring durum wheat grown in developing countries traces its origins to the durum wheat program at CIMMYT in Mexico. The Center regularly sends out seed samples to national breeding programs around the developing world, and the most suitable in each region are used to breed local varieties. When mutations in the leaf rust fungus allowed it to bypass the resistance mechanisms in durum wheats, the breeding team at CIMMYT was faced with a serious problem.

“We had to rebuild the program, because you can no longer use something that becomes susceptible to a disease. That’s no service to the national programs or farmers in developing countries,” says Ammar, who comes from Tunisia. He is acutely aware that the work he is doing will have a major impact in developing countries where durum wheat is grown.

It might have been easy to look this as a single problem—producing disease-resistant plants or plants that can produce more grain—but the team realized the challenge was much more complicated. Farmers in developing countries need more than grain if their livelihoods are to improve. They need grain that is high in quality and for which there is a market.

Breeding itself is a process of combination and then elimination—selecting potentially good parent seeds with desirable characteristics and crossing them, then eliminating the offspring plants that don’t measure up. The process is cyclical and repeated until the breeder is satisfied that all required characteristics have been incorporated into the new wheat plants.

Leaf rust reduces yields enough to make growing susceptible varieties a losing proposition for farmers. Their needs were at the heart of the breeding strategy devised by the breeding team.

“So their priority becomes ours and once objectives are defined with our clients and their respective markets in mind, then I start thinking about the plants—how would a plant or a certain cross or combination of genes achieve that objective in the most efficient, fastest way possible,” Ammar says.

The breeders knew that disease resistance was vital but quality that was acceptable to farmers and their markets was equally essential. At the same time they thought they could enhance the performance of the wheats under drought stress and incorporate resistance to other diseases. In the beginning they had to sacrifice yield and other key characteristics to be sure they had resistance to the leaf rust, the biggest problem durum wheat growers were facing. But once that was done, the team focused on making the best possible wheats from all other perspectives.

“Now we’re back to the point where we can address yield, drought tolerance and quality very effectively because we know we have enough variability for rust resistance. It’s no longer the critical trait,” says Ammar.

The most critical trait now might well be the color or the quality of the gluten in durum wheat grains. Last year farmers in the Yaqui Valley of Mexico grew close to 150 000 ha of a durum wheat variety that yielded well and stood up to leaf rust. Unfortunately, because its grain did not have enough yellow pigment, desired by the export market, there was little market for the wheat except as pig feed. Many of the 2500 new lines that Ammar is testing outperform that variety in yield and in the most important quality traits

The best of the lines at the CIMMYT breeding station will be sent to national programs for evaluation. Mexico has already begun to evaluate in parallel so it will be ready as soon as possible to release new varieties based on the CIMMYT lines to the national production system .

For more information Karim Ammar, Wheat Breeder (k.ammar@cgiar.org)

CIMMYT E-News, vol 3 no. 9, September 2006

The Nepal Hill Maize Research Project, supported by the Swiss Agency for Development and Cooperation (SDC), reaches out to Nepal’s poorest farmers with new varieties and farming practices selected by the farmers themselves.

Coca Cola, arguably the world’s most ubiquitous commercial beverage, has not yet reached the villagers and farmers who live on top of the cloud-shrouded hills of eastern Nepal. That’s how remote they are. There is a road, but it is 600 meters below in the valley and the only way in and out of the village is via a precarious, rubble-strewn and sometimes terrifyingly steep foot-path. Everything must be carried up and down this track on people’s backs. Here the staple food for centuries has been maize but many farmers in the region cannot grow enough maize to last the year. Their needs have provided a focus for work in which CIMMYT, the Nepal Agricultural Research Council (NARC), SDC, and other partners, reach these “unreached” people.

One of them is Bishnu Maya. She is a single mother of three who farms 0.6 hectares of terraced land on the steep slopes. She is a very good farmer but it takes every penny she earns to make sure her children can go to school. “With education they can get jobs and have a better life,” she says. Bishnu Maya is a ‘dalit’; the poorest of the poor in Nepal, an untouchable often shunned by better-born villagers. Nevertheless, her tiny farm is a marvel. She grows maize, millet, tomatoes, and cucumbers on her land. She has a water buffalo, two cows, some chickens, and goats. A year ago electricity came to the village and now she has a small radio and a light bulb. What she has not had until now is enough maize to last the year. The traditional varieties have small ears, one per plant, and the maize plants themselves grow very tall and often fall down in the wind, not only reducing the maize yield but also damaging the intercropped plants below them.

Maya agreed to help in participatory evaluations of maize varieties developed with material from CIMMYT and NARC that could overcome the main barriers to production on her land. She uses some of her land for a demonstration plot of the variety she has selected as the best replacement for her traditional maize. It is shorter with a sturdier stalk, has two large ears per plant and matures earlier than the maize she has been used to growing. On top of that the new variety stays green after the maize is mature, so it makes a better feed for her livestock.

The project has intentionally focused on women farmers and those who cannot produce enough food to feed their families, testing and promoting technologies that can be implemented by the farmers themselves. While the initial trials are conduced at the NARC research station at Pakhribas, an hour’s drive away once you reach the road in the valley, vital research work is conducted with farmers like Maya on their farms. In the past recommendations about varieties and agricultural practices were based on trials conducted exclusively at research stations, rarely taking into account the real world in which the hill farmers like Maya live and work. “Even on-farm research tended to try to create conditions on farms that matched the research stations, rather than finding solutions to existing farm problems,” says CIMMYT’s Memo Ortiz-Ferrara, who leads the project.

The new approach has helped farmers choose more appropriate varieties based on their own criteria from a “basket of choices” (5-10 varieties are offered in one season). It has also helped to expand areas growing new varieties on one hand, and improve crop management practices on the other. Depending on the location, farmers have observed 20-50% higher grain yield with the new varieties.

“Now I have enough and can sell some surplus to pay for my children’s education,” Bishnu says.

The second phase of the project is just coming to an end and an evaluation team has begun a series of in depth interviews with participating researchers and farmers to determine the overall impact.

Participatory research is a vital part of many CIMMYT projects around the world (see the companion story: CIMMYT researchers say participatory research supports their achievements).

For information contact Memo Ortiz-Ferrara (g.ortiz-ferrara@cgiar.org)

CIMMYT E-News, vol 2 no. 8, August 2005

Remembering the life of Dr. Robert Havener, former Director General of CIMMYT.

August 3rd was a sad day in the life of CIMMYT and for the world of agricultural research for development. Former Director General Robert D. Havener died in California at the age of 75. The Chair of the CIMMYT Board of Trustees, Dr. Alex McCalla, represented the center at the memorial service, held on August 20th in Los Olivos, California.

Dr. Havener was one of the true pioneers in the global agricultural research system, working for the world’s rural poor for more than five decades. He led CIMMYT from 1978 to 1985 as the center’s third Director General, bringing our center recognition as one of the leading international agricultural research organizations in the world. When he came, Dr. Norman Borlaug was director of the wheat program and Dr. Earnest Sprague the director of the maize program. During his leadership CIMMYT expanded its regional presence and strengthened the economics program. Dr. Havener believed that the program should not work in isolation but in tight integration with the main crop programs. Around CIMMYT he was known for his ability to make quick but sound judgments and for his office that was open to all, even the most junior scientist. With donors he was a forceful and successful advocate for CIMMYT and CIMMYT’s mission. He stewarded the center through a financial crisis in the 1980s and by the end of his term as Director General had increased dramatically the number of core donors.

Of course Robert Havener was more than just the former DG of CIMMYT. For 14 years he worked as a senior agricultural program officer for the Ford Foundation. He served as interim Director General at both CIAT (1994) and IRRI (1998) and was instrumental in the founding of ICARDA and ILRI. He served as Chair of the ICARDA Board of Trustees from 1999 to 2003. He was the founding President of the Winrock International Institute for Agricultural Development, a Fellow of the American Association for the Advancement of Science, an advisor for the World Food Prize and sat on the Board of Directors of Sasakawa Africa Association / Global 2000 Program, whose president is Dr. Borlaug.

Dr. Havener was always a friend of CIMMYT, right to the end and could always be counted upon for wise council and sage advice. He followed with interest and passion the changes taking place at CIMMYT. Bob Havener devoted his life to making a difference for the rural poor. We are all diminished by his loss.

March, 2004

On 12 March 2004, CIMMYT took a modest but historic step in the development of drought tolerant wheat, when a small trial plot was sown to genetically modified (transgenic) wheat in a screenhouse at the Center’s headquarters in Texcoco, Mexico. This is the first time that transgenic wheat has been planted under field-like conditions in Mexico, and rigorous biosafety procedures are being followed.

Drought is arguably the world’s most important agricultural production problem. In developing countries, millions of hectares of wheat are grown in areas that often experience drought, and the problem is projected to worsen with climate change. A plant’s ability to withstand dry conditions at critical periods in its growth can make the difference between food and famine for poor households. Developing drought-tolerant wheat and maize varieties that perform well under diverse conditions is a top priority at CIMMYT, where innovative research—conventional as well as transgenic—is pursued to meet this complex and difficult challenge.

CIMMYT researchers have well-founded hopes that the wheat they are testing will withstand serious droughts. This wheat carries the DREB1A gene from the plant Arabidopsis thaliana. The gene has been shown to confer tolerance to drought, low temperatures, and salinity in Arabidopsis, a plant species related to wild mustard (see Nature Biotechnology 17:287-291).

Previous experiments with DREB wheat grown in pots in CIMMYT’s biosafety greenhouse provided very encouraging results. The new screenhouse trial will enable researchers to see whether the DREB wheat responds similarly under more “natural” conditions.

This trial is the first time that a food crop carrying the DREB gene has advanced to this level of testing. If the results are positive, there are major implications for its use in other cereal crops, such as rice, maize, and barley. CIMMYT is considering testing the DREB gene in the drought-tolerant wheat it has developed through conventional breeding, to see if the resulting plants can use water even more efficiently.

A comparison of DREB and control wheat plants (DREB plants on the left, control plants on the right in both of the above photographs), after 10 days without water.

The promising work with the DREB wheat would not have been possible without the generosity of the Japan International Research Center for Agricultural Sciences (JIRCAS), which provided the gene construct, and funding from Australia’s Molecular Plant Breeding-Cooperative Research Centre.

The transgenic wheat trials were approved in December 2003 by Mexican authorities under strict biosafety provisions to ensure that the plants do not inadvertently cross with conventional wheat plants:

• Access to the enclosed screenhouse trial is tightly restricted.
• No wheat plants are grown within 10 meters of the screenhouse trial.
• The spikes (flowers) of the plants are covered and isolated from the environment by glassine bags.
• Plant materials are destroyed in an autoclave at the end of the trial.
• The trial is monitored by Mexican authorities and the CIMMYT Biosafety Officer.

But the greatest biosafety measures are provided by the wheat plant itself. Wheat is a “perfectly self-pollinated crop,” with 99% of fertilization occurring within the sheathed spike of the plant, where male and female plant components share the same floret. Even in conventional breeding, researchers have to resort to a series of carefully executed, laborious procedures to cross one wheat plant with another. This makes wheat very different from maize, which freely pollinates and thus exchanges genes with other maize plants. Cross-pollination is further limited because wheat pollen is heavy and does not travel far, and because the pollen remains viable for only 20-30 minutes.

Details
CIMMYT Research Team
Alessandro Pellegrineschi, Matthew Reynolds, Richard Trethowan, Mario Pacheco, Rosa Maria Brito, Rosaura Almeraya, Scott McLean, and David Hoisington.

Trial Purpose
To evaluate the performance under water-stress and normal irrigation conditions of transgenic bread wheat lines containing the Arabidopsis thaliana DREB1A under the control of the stress inducible promoter rd29a.

Trial Design
MPB-Bobwhite26 lines, each containing the DREB1A gene driven by the rd29A promoter are planted in a randomized lattice design. The non-transformed MPB-Bobwhite26 line is used as a control and 10 drought tolerant lines are used for comparison purposes. Two water regimes are being evaluated: full irrigation versus no irrigation, except one at planting.

For further information, contact Dr. Alessandro Pellegrineschi

Download pdf version (170 KB)

CIMMYT E-News, vol 3 no. 10, October 2006

Global Rust Initiative tackles a clearly present danger.

When wheat scientists and policy makers convened in Alexandria, Egypt earlier this month, one might have been forgiven for thinking that a war was afoot. And it is. Scientists are launching an offensive against wheat stem rust, an old foe of farmers that is threatening resurgence.

Words like ‘emergency’, ‘disaster’, ‘catastrophe’, and ‘devastation’, were used at the meeting to paint a picture of the havoc that epidemics of the fungal disease, also known as black rust, could precipitate on the world’s food security and economy. “This is a global threat…,” CIMMYT Director General Masa Iwanaga told the First International Workshop of the Global Rust Initiative (GRI), 9-11 October. “The risk of a stem rust epidemic in wheat in Africa, Asia and the Americas is real, and must be averted before untold damage and human suffering is caused,” said Mahmoud Solh, Director General of the International Center for Agricultural Research in the Dry Areas (ICARDA). Preliminary field evidence from Kenya indicated that many more varieties of wheat could be threatened by rust than previously thought.

The GRI—a consortium coordinated by CIMMYT and ICARDA that involves agricultural research institutes from 30-plus countries—will use scientific knowledge and global cooperation as its primary ammunition to fight the disease. Tactics will include worldwide surveillance for virulent strains of the stem rust fungus Puccinia graminis (‘trap nurseries’—small fields where wheat known to be susceptible to the new disease has been planted) have been positioned in at-risk countries in Africa, the Middle East and South Asia); zeroing in on resistance genes and using these in breeding programs; and accelerated seed multiplication and dissemination of the new, resistant breeds. “We basically have to replace all the wheat in the world,” says GRI Coordinator, CIMMYT wheat scientist Rick Ward.

It is no mean task; farmers and breeders select wheat varieties for their high yield, robustness against pests and diseases, but also properties such as grain color, maturity period, and bread making quality, and the GRI’s work will have to keep these in mind. Furthermore, preferences vary by region, often depending on the form in which the wheat arrives at the table. Seed delivery will also need to be addressed.

Infection with the fungal disease first appears as deep orange pustules on young wheat stems, and without prompt intervention with fungicides, farmers’ fields are converted into a tangled mass of black stems with shriveled grain. Severe infections can lead to total crop failure. A new variant of the fungus, Ug99, has established itself in bread wheat farmers’ fields in Kenya and Ethiopia, and resource-poor smallholders who cannot afford fungicides are quickly losing the battle against stem rust.

Until new, resistant varieties are in the hands of farmers, Ward says part of the GRI’s resources will be directed towards an aggressive regimen of fungicides to suppress stem rust hot spots before they spread. “A stem rust epidemic is much like a bush fire; if it’s not contained, it becomes exceedingly difficult to stop,” he says.

Researchers at the Alexandria meeting were relieved to hear that GRI-coordinated screening of twelve thousand wheat cultivars has yielded a handful of potential Ug99-resistant candidates. This positive news came from researchers at Njoro, a high-altitude research station of the Kenya Agricultural Research Institute (KARI), and the Melkasa station of the Ethiopian Institute of Agricultural Research (EIAR). The promising varieties are being fast-tracked for multiplication and release to farmers. Ward announced that the GRI will now use molecular breeding, which reduces the breeding process by several years, as a routine.

Even with modern breeding and communication technologies, the GRI’s success will hinge on the spirit of global cooperation to overcome blights that threaten the world’s food security.

For more information contact r.ward@cgiar.org
www.globalrust.org