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research: Genetic resources

Improving wheat for world food security

cimmyt-wheatIn order to contribute to world food security, the International Research Initiative for Wheat Improvement (IRIWI), supported by research organisations and funding agencies from about ten countries, has been adopted by the Ministers of Agriculture of the G20. INRA, with the Biotechnology and Biological Sciences Research Council (UK) and the International Maize and Wheat Improvement Center (CIMMYT, Mexico), will contribute to the coordination activities of the IRIWI during the first four years of the project.

The historic agreement between the Ministers of Agriculture of the G20 on 23 June 2011 in Paris underlines the importance of increasing world agricultural production, in particular that of wheat, to resolve the urgent challenges of hunger and food price volatility. Already very active on this issue, INRA, together with other national and international research and funding organisations from about ten countries, will launch the International Research Initiative for Wheat Improvement (IRIWI) in 2011. This initiative aims at reinforcing synergies between bread and durum wheat national and international research programmes to increase food security, nutritional value and safety while taking into account societal demands for sustainable and resilient agricultural production systems.

Wheat is one of the main staple crops in the world but the present production levels do not satisfy demand. With a world population of 9 billion in 2050, wheat demand is expected to increase by 70%. Annual wheat yield increases must jump from the current level of below 1% to at least 1.7%.

Repeated weather hazards in a context of global change, the constant rise in oil prices, speculation on agricultural markets are some of the factors reinforcing volatility of wheat prices and aggravating food insecurity in numerous countries.

Strengthening coordination of world wheat research

IRIWI will coordinate worldwide research efforts in the fields of wheat genetics, genomics and agronomy. Both Northern and Southern countries share the need to improve wheat yield, tolerance to stress, pathogens and pests, as well as wheat resource use efficiency. Improved agronomic practices and development of innovative cropping systems are also a priority. Several large national research programmes on wheat have been launched recently in Northern countries. CIMMYT and ICARDA have presented a new CGIAR research programme called WHEAT for the developing world.

As part of its activities, IRIWI will provide a forum to facilitate communication between research groups, identify potential synergies and encourage collaborations among major existing or emerging nationally, regionally and internationally (public and private) funded wheat research programmes. It will also support the development of publicly available integrated databases and platforms and establish and periodically update priorities for wheat research of global relevance.

Sharing resources, methods and expertise to improve and stabilise yields

The on-going efforts to decipher the wheat genome sequence, as well as the development of high throughput genotyping and phenotyping tools, will provide new ways to exploit more efficiently the available genetic diversity and create new wheat varieties by public and private breeders. Development and adoption of precise and site-specific management techniques will lead to the improvement of production systems. The IRIWI will facilitate and ensure the rapid exchange of information and know-how between researchers, and will organize knowledge transfer to breeders and farmers.

These actions will allow the creation of improved wheat varieties and the dissemination of better agronomic practices worldwide in the next 15 years. These new wheat varieties and agronomic practises will allow farmers to stably produce more and better wheat in different environments.

Presentation of the International Research Initiative for Wheat Improvement (pdf)

IRIWI reinforces INRA’s long-term involvement in research in wheat improvement. Recently, the BREEDWHEAT project was selected by the French Stimulus Initative. BREEDWHEAT is carried out in coordination with or contributes to other international initiatives, such as the WHEAT-Global Alliance project for food security in Southern countries, conducted by the CIMMYT and the International Wheat Sequencing Programme coordinated by the IWGSC.

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CIMMYT researchers say participatory research supports their achievements

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

sep01Farmers participate in a significant portion of CIMMYT research and technology testing, according to center researchers, and the scientists believe this makes their efforts more effective.

The combined budgets of 19 CIMMYT projects cited by their principal investigators in a 2004 survey as including participatory research components exceeded US$9 million—roughly a quarter of the center’s total budget at the time. “Not all that money was spent on participatory activities, but the figure bespeaks a significant investment,” says Nina Lilja, Agricultural Economist in the on Participatory Research and CGIAR Systemwide Program Gender Analysis for Technology Development and Institutional Innovation (PRGA Program).

This conclusion was one outcome of a study on participatory research at CIMMYT by Lilja and Mauricio Bellon, Director, Diversity for Livelihoods Program, International Plant Genetic Resources Institute (IPGRI), and former Human Ecologist at CIMMYT. “Nearly all respondents felt that the use of participatory approaches had been worthwhile and most believed participatory methods had added value to the research,” says Lilja. “In support of this, many respondents provided evidence of project achievements through use of participatory approaches.”

Participatory research—particularly where farmers help evaluate and promote new crop varieties or farming practices—have been used increasingly in CIMMYT research in recent years. This study represents the first-ever analysis of participatory approaches, from the perspective of center researchers. Through the 2004 survey, the scientists reported on projects they considered as having a participatory component. The range of the study was broad: there was great variation in the types and characteristics of participatory research for which researchers provided information. The survey allowed characterization of the projects, but not further critical analysis of the quality or the appropriateness of the methods applied nor an objective assessment of impacts. Information was received for 19 projects from 18 scientists—15 male, 3 female; 5 social scientists, 13 biophysical scientists. Sixteen of the projects involved farmer-participatory research; three targeted national-program scientists and seed agronomists. Most of the projects covered work in sub-Saharan Africa and Asia; only two had activities in Latin America. About a third of the projects involved participatory testing of crop varieties or production practices; the remainder involved focus group activities or stakeholder meetings.

The issues most frequently addressed via participatory methods related to increasing productivity and understanding farmers’ needs and constraints. “Participatory research at CIMMYT was largely of the functional type—that is, aimed at improving the efficiency and relevance of the research, rather than specifically to empower farmers,” says Bellon. “Also, there was an overall lack of awareness of multiple beneficiaries or of differential effects owing to gender. None of the respondents had been trained previously in participatory methods.”

Two major recommendations of this report for adding value to CIMMYT’s participatory research efforts are to (1) create a more conducive environment within the center for scientists to share experiences and learn from each other, and (2) better document outcomes and impacts of the center’s participatory research.

To view or download a copy of the study, click here.

For further information, contact John Dixon (j.dixon@cgiar.org)

Willkommen, Herr Bundespräsident!

alemania-300x227The long-standing and fruitful relationship between Germany and CIMMYT received a boost on 01 May 2011 when, as part of an official tour of Latin America, the President of the Federal Republic of Germany, Christian Wulff, visited CIMMYT headquarters to learn more of the center’s work and discuss strengthened partnerships. President Wulff was accompanied by his wife, Bettina, and nearly 60 distinguished guests including German vice ministers and members of parliament, embassy personnel, and business and media representatives. Greeting the guests were CIMMYT Director General Tom Lumpkin and several of the center’s German and German-speaking staff.

After touring the main exhibition hall showcasing Dr. Norman Borlaug’s achievements and contributions to agricultural development, including his Nobel Prize of 1970 and the Aztec Eagle of the same year from Mexico, the entourage attended a presentation by Hans-Joachim Braun, Director of CIMMYT’s Global Wheat Program. The talk addressed food security and related constraints—climate change, the rising demand for grains, the increasing scarcity of resources like land, water, and fertilizer—as well as CIMMYT’s work in the developing world and its relationship with Germany, a long-term and significant supporter of the center. To name just a few examples, German contributions have funded work on stress tolerant maize for Africa, a regional wheat network for Central Asia, and wheat pathology research for South Asia. German staff at CIMMYT and our partnerships with German universities and institutes have been of enormous value in getting improved technology to farmers.

The whirlwind tour then moved to the seed bank, with exhibitions of maize and wheat genetic resources outside and a visit inside to the upper seed storage chamber. In an impromptu closing statement, President Wulff thanked CIMMYT and described his positive impression of the visit and Braun’s presentation, which he called one of the clearest and most fact-based he had ever heard. Reports on the visit in the German media have referred to CIMMYT as a “highly-regarded research center.”

In addition to Lumpkin and Braun, CIMMYT staff interacting with the guests included Marianne Bänziger, deputy director general, research and partnerships; Scott Ferguson, deputy director general, corporate services; Peter Wenzl, head of the crops research informatics lab; Susanne Dreisigacker, molecular biologist and head of marker applications in wheat; GIS expert Kai Sonder; agricultural economist Tina Beuchelt; Marc Rojas, coordinator of the International Strategy for Maize Improvement; and Petr Kosina, assisting with the event management.

Click here to view/hear…

Winning in the long run

CIMMYT E-News, vol 3 no. 12, December 2006

Three decades of research into drought tolerant maize by CIMMYT and a very strong set of partnerships has made a difference in the lives of African farmers. That achievement has been recognized by the awarding to CIMMYT of the 2006 CGIAR King Baudouin Award.

It began with a small experiment to try to improve the lowland tropical maize population called Tuxpeno for drought tolerance in Mexico in the1970s. The United Nations Development Program (UNDP) started to invest in more significant research around drought tolerant maize in 1986. In the mid-1990s, the focus of the work moved to Africa—to the most challenging maize growing environments world-wide: southern and eastern Africa, where maize is a source of food and livelihoods for some 250 million people.

Today, sufficient seed has been produced to plant over 2.5 million hectares of land in eastern and southern Africa with new varieties that produce more maize both when dry spells occur and under good conditions. The road in-between involved the building of a large partnership with donors, national agricultural research programs, extension programs, small-scale seed producers, community seed producers and individual farmers; developing new ways of screening germplasm in real world conditions; and enhancing farmer-participatory methods to select the best and disseminate the best.

CIMMYT and its partners employed novel methodologies in breeding that were pro-poor according to Marianne Bänziger, the director of CIMMYT’s Global Maize Program.

“Traditional varieties have been developed with fertilizer applied under good rainfall conditions. CIMMYT took a completely different route,” she says. “We took the varieties; we exposed thousands of them to very severe stress conditions—drought, low soil fertility. We selected the best. We brought them to farmers and farmers told us which ones they liked.”

The projects invested in over 25 fully-equipped managed-stress screening sites and more than 120 testing sites owned and operated by national programs. A network was established involving CIMMYT, public National Agricultural Research Systems (NARSs), and the private sector to systematically test new varieties and hybrids from all providers for the constraints most relevant to smallholder farmers in eastern and southern Africa. This network recently provided proof that the stress breeding approach works. In a simple comparison between all maize hybrids from CIMMYT’s stress breeding approach and a similar number of hybrids developed by reputable private companies using the traditional approaches—using 83 hybrids, 65 randomly-stressed locations across eastern and southern Africa, and 3 years of evaluation—the results demonstrated that, under production circumstances most similar to those of resource-poor farmers in Africa (that is, at yield levels of 1–5 tons per hectare), the CIMMYT varieties yielded on average 20% more in the most difficult conditions and 5% more under favorable conditions. Among these the best stress-tolerant hybrids increased yields as much as 100% under drought, showing the great potential contained in maize genetic resources.

The final selection was done through a participatory methodology called the “mother-baby” trial system, in which farmers managed some “baby” plots in their own fields while NGOs, researchers and extension staff conducted a “mother trial” in the center of their community. This way farmers could see how potential varieties actually performed under local conditions.

As a result, more than 50 open-pollinated and hybrid varieties have been disseminated to public and private partners, NARSs, NGOs and seed companies, for seed production and dissemination to farmers. “None of this success would have been possible without the collaboration of many dedicated researchers, NGO and extension staff from the public and private sector.” says Bänziger. “They were the ones evaluating varieties under diverse conditions with farmers. They also started to adopt the new breeding methods in their own programs, developing their own varieties, engaging in seed production and tackling the challenge of getting seed to farmers.”

The story is not finished. CIMMYT researchers are sure the genetic diversity in maize is sufficient to push the drought tolerance in new maize varieties significantly further. “Yield gains are such that with every year of research we can add another 100 kg of grain under drought,” says Bänziger. The greatest challenge is to incorporate these gains into adapted varieties and get the seed to the farmers who need it most—a tremendous task and opportunity given the looming threats of climate change.

For more information, Marianne Bänziger (m.banziger@cgiar.org)

USD 170 million research program to help maize farmers worldwide

cimmyt-maize-farmersBold Initiative Tackles Hunger in Developing World

Washington, July 6, 2011 – The Consultative Group on International Agricultural Research (CGIAR)—the world’s largest international agriculture research coalition—today announced a USD 170 million global alliance and program to expand and accelerate research into maize, the preferred staple food source for more than 900 million people in 94 developing countries, including one third of the world’s malnourished children.

“This program aims to double the productivity of maize farms, while also making those farms more resilient to climate change and reducing the amount of land used for growing the crop,” said Carlos Perez del Castillo, CGIAR Consortium Board Chair.  “As a result, farmers’ incomes are expected to rise and their livelihood opportunities to increase, contributing to rural poverty reduction in developing countries.”

cimmyt-maize-plantingThe CGIAR applies cutting-edge science to foster sustainable agricultural growth that benefits the poor. The new crop varieties, knowledge and other products resulting from the CGIAR’s collaborative research are made widely available, at no cost, to individuals and organizations working for sustainable agricultural development throughout the world.

Under the research program, 40 million smallholder farm family members are expected to see direct benefits by 2020 and 175 million by 2030.  The program is expected to provide enough maize to meet the annual food demands of an additional 135 million consumers by 2020 and 600 million by 2030.

The program will be implemented by the International Maize and Wheat Improvement Center (CIMMYT), and the International Institute of Tropic Agriculture (IITA).

The announcement came as the CGIAR celebrated its 40th anniversary at a ceremony in Washington attended by the President of the World Bank Group, as well as the heads of several of the 15 research centers that make up the CGIAR Consortium of International Agriculture Centers.

Inger Andersen, Vice President of Sustainable Development at the World Bank, and Chair of the CGIAR Fund Council, said the first target group to benefit from the enhanced maize research program would be smallholder farmers who live in environments prone to stress and who have poor access to markets.

“Small holder farmers are among the most vulnerable people in developing countries.” she said. “They should be among the first we seek to help. Enabling these people to produce more and better maize quickly and reliably will help to ensure their well being, as well as that of their communities.”

Studies carried out by CIMMYT show that the demand for maize in the developing world is expected to double between now and 2050.

“This is a highly ambitious project to address world hunger,” said Thomas Lumpkin, Director General of the International Maize and Wheat Improvement Center (CIMMYT). “It will take an enormous amount of work and cooperation between public and private sector institutions to meet the goals. The global challenges facing mankind are immediate and chronic; the time to act is now. Millions of lives depend on our ability to develop sustainable solutions to feed more people with fewer resources than ever before.”

The global alliance that will carry out the research program includes 130 national agricultural research institutes, 18 regional and international organizations, 21 advanced agricultural research institutes, 75 universities worldwide, 46 private sector organizations, 42 non-governmental organizations and farmer associations, and 11 country governments that will host offices dedicated to the program.

The Consultative Group on International Agricultural Research (CGIAR) is a global partnership that unites organizations engaged in research for sustainable development with the funders of this work. The funders include developing and industrialized country governments, foundations, and international and regional organizations. The work they support is carried out by 15 members of the Consortium of International Agricultural Research Centers, in close collaboration with hundreds of partner organizations, including national and regional research institutes, civil society organizations, academia, and the private sector. www.cgiar.orgwww.consortium.cgiar.org

The International Maize and Wheat Improvement Center, known by its Spanish acronym, CIMMYTÂŽ (staging.cimmyt.org), is a not-for-profit research and training organization with partners in over 100 countries. The center works to sustainably increase the productivity of maize and wheat systems and thus ensure global food security and reduce poverty. The center’s outputs and services include improved maize and wheat varieties and cropping systems, the conservation of maize and wheat genetic resources, and capacity building. CIMMYT belongs to and is funded by the Consultative Group on International Agricultural Research (CGIAR) (www.cgiar.org) and also receives support from national governments, foundations, development banks, and other public and private agencies.

See also:
Maize Global Alliance for Improving Food Security and the Livelihoods of the Resource-poor in the Developing World

Executive summary | Full document

The Quick Guide to the “New” CIMMYT

Click here to see pdf version, 190KB
CIMMYT has developed a strategy for building on its core strengths to address the challenges of international agricultural research in the years to come: the need to bring about a real improvement in the livelihoods of the poor; the emerging biophysical, socioeconomic, and political constraints to agriculture in developing countries; the growing range of partners involved in research, extension, and development; and the changing financial landscape for public-sector research.The new strategy requires CIMMYT to change in important ways. The prospect of a “new CIMMYT” has generated much interest but also many questions, which this fact sheet attempts to answer.

1. Foundations of the new CIMMYT

CIMMYT’s recognized strength in maize and wheat improvement for developing countries, its experience in research on maize and wheat systems, and its broad network of partners, ranging from farmers to government ministers, are the foundations of the new CIMMYT. CIMMYT firmly believes that seed with characteristics valued by farmers—for example, drought tolerance or disease resistance—provides a safety net for poor farm households, enabling them to survive bad years, profit from good ones, and pursue more diverse livelihood strategies. But how that seed is developed, how it is integrated with resource conserving technologies, and how farmers’ options are influenced by policies, are fundamental issues that CIMMYT is addressing in the changes that are underway.

2. A mission that puts people first

CIMMYT’s mission continues to emphasize improved food security, the productivity and profitability of farming systems, and the protection of natural resources. However, the new mission statement highlights CIMMYT’s commitment to the poor and acknowledges the central role of CIMMYT’s partners in sharing knowledge, catalyzing innovation, and making an impact: CIMMYT acts as a catalyst and leader in a global maize and wheat innovation network that serves the poor in developing countries. Drawing on strong science and effective partnerships, we create, share, and use knowledge and technology to increase food security, improve the productivity and profitability of farming systems, and sustain natural resources.

3. A new approach to partnering

As indicated in the mission statement, CIMMYT will engage in more strategic partnering and networking to catalyze and effect change within rural communities. Some of CIMMYT’s activities will be outsourced to partners in the public and private sectors. CIMMYT will engage in more collaborative priority setting and implementation of research with its partners, including other CGIAR Centers.

4. A new approach to research

To better clarify and respond to local needs, the contributions of cropping systems researchers, social scientists, plant breeders, molecular biologists, and many other disciplines must be joined together. CIMMYT’s new research programs—Genetic Resources, African Livelihoods, Rainfed Wheat Systems, Tropical Ecosystems, Intensive Agroecosystems, and Global and Strategic Research—rely on multidisciplinary teams to work on research priorities identified with CIMMYT’s partners.

5. How the programs fit together

The new programs are part of a continuum that extends from the characterization and use of genetic resources, to the development of maize and wheat varieties for specific ecologies and regions, to the use of these varieties in systems research to address local needs, and finally to the resulting global information that enables CIMMYT to learn from its experience and improve its effectiveness.

The global program on Genetic Resources develops information and inputs—primarily specialized breeding materials and methods—that enable the ecoregional programs to do their work more rapidly and effectively. The program works on genetic traits that are identified as priorities by the eco-regional programs (for example, drought tolerance).

The eco-regional programs—African Livelihoods, Rainfed Wheat Systems, Tropical Ecosystems, and Intensive Agro-ecosystems—emphasize maize and wheat systems research to improve the livelihoods of the poor in their respective regions and ecologies, where the challenges and opportunities for making an impact are more likely to be similar. These programs are designed to ensure that the research agenda is driven by local needs.

The program on Global and Strategic Research synthesizes and communicates what is learned across all of CIMMYT’s research programs. It assembles, manages, and provides strategic knowledge and information for research (for example, data from the molecular to the field level), supports capacity building, provides information for setting research priorities, and assesses the impact of research.

6. Working globally

CIMMYT’s research leadership and management have been decentralized to permit the Center to work from a global rather than a central base. The research and management teams now comprise staff in Asia, Africa, and Latin America.

7. Contact points

If you are accustomed to contacting a particular researcher with whom you have worked over the years, please continue to do so. If that researcher is no longer working on your particular area of interest, he or she will connect you with someone who is.

For global and eco-regional programs:

For information on a particular commodity or discipline:

To obtain seed:

Seed health and quarantine information:

Information on capacity building:

  • Contact the CIMMYT office in your region to learn about current and planned capacity building opportunities throughout the world.

Nutrition Better but Maize Diversity Down in Chiapas

March, 2005

noticias1Farmer Juan Castillejos Castro of the village Dolores, Jaltenango, state of Chiapas, in southeastern Mexico, leaned forward in the humid, mid-morning heat and pondered the question: had household nutrition improved in the last 10 years? “From the mid-1970s to the mid-1980s, even I was malnourished to the point I couldn’t work,” he says. “Now things have gotten better, and the credits have helped a lot.”

Like many farmers in the “La Frailesca” region of Chiapas, Castillejos has been growing improved, hybrid maize, through a state-sponsored program that offers seed plus other inputs (fertilizer, pesticides, among them) and services (technical advice, crop loss insurance, to name two) on credit, to be repaid at harvest. For the last decade, government policy has also discouraged the burning of crop residues. Burning helped farmers control weeds and pests, but bared often steep, hillside plots to eroding winds and rain and deprived soils of organic matter. Castillejos and most peers now practice a more resource-conserving style of agriculture, sowing with a stick directly into the last year’s crop residues, without plowing or burning.

Folk Varieties Fading in La Frailesca

Unlike many farmers adopting the hybrids, Castillejos still grows small plots of the local maize varieties developed through selection by millennia of predecessors. The local varieties feature a better grain type for tortillas and other preferred foods. Their weaknesses include tallness and a tendency to topple easily. This and their relatively low yields have put them on the road to extinction, according to Dagoberto Flores, research assistant in CIMMYT’s Impacts Assessment and Targeting Program.

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“We still need a systematic study on this,” says Flores, “but I would guess that half the local varieties have disappeared, and only 30% of farmers are growing any local materials.” Flores and an associate, Alejandro Ramírez López, just spent a month surveying 120 farm households in 4 communities in the region. With funding from the United Nations Food and Agriculture Organization (FAO), they are comparing the costs to farmers of obtaining seed through formal versus informal supply systems and evaluating farmers’ risks, from village to village.

The village of Dolores Jaltenango lies in the mountainous countryside that bred the Zapatista uprising and is a gateway for undocumented immigrants from Central America. Nine-tenths of maize is relegated to steep hillsides—cattle raising and plantation agriculture claim the choice lowlands. “Dolores is one of the poorer communities in the area,” says Flores. “Dwellings are adobe with dirt floors. There’s normally one large sleeping quarters for an average 10 people, including parents, children, and married children’s spouses.”

Flores and Ramírez are concerned about La Frailesca’s farmers. The prices of the seed technology packages are rising steadily, and subsidies are being reduced. They fear that if farmers lose their native seed, they may have no fallback position. “Farmers look at their neighbor’s yields or the size of the ears, but most haven’t done the math on all the costs and benefits of the new technology,” Ramírez says. He cites the results of last year’s serious drought as an example: “Many farmers had poor crops. But some didn’t qualify for crop loss insurance benefits. Now they’re having trouble paying back their credit debts.”

CIMMYT’s Role: Conserving and Replenishing Diversity

According to Flores, CIMMYT staff have collected and preserved important samples of the Frailesca’s farmer varieties in the center’s germplasm bank. The bank contains seed collections for an estimated 80% of all Latin American maize diversity, including many varieties no longer sown by farmers. The seed is kept in trust for humanity, under a 1994 agreement with FAO. Working with partners in 13 countries in the Americas, center staff have coordinated the rescue, regeneration, and back-up storage of more than 10,000 seed samples of unique maize varieties from this hemisphere. CIMMYT and partners from the Mexican National Institute of Agriculture, Forestry, and Livestock Research (INIFAP) recently restored seed of local varieties to farmers in Oaxaca, Mexico, and could do the same for Chiapas farmers, should this become necessary, Flores says.

Fitting into FAO Research Efforts

Environmental economist Leslie Lipper at FAO will draw on the survey and its results in an emerging, multi-country study on how market access to crop genetic resources affects farmers’ welfare and on-farm crop biological diversity, according to Kostas Stamoulis, Chief of the FAO Agricultural Sector in Economic Development Service (ESAE). “CIMMYT’s work will provide unique data on farmer seed sourcing choices,” says Stamoulis. “Among other things, we’ll get a better read on how those choices are affected by the transaction costs of market participation and farmer’s perceptions of risk.” The study is one of three major ESAE efforts to understand the role of markets in rural livelihoods and environmental sustainability.

Earliest Mexican wheats supply latest useful traits

CIMMYT E-News, vol 5 no. 6, June 2008

jun05Centuries ago, Spanish monks brought wheat to Mexico to use in Roman Catholic religious ceremonies. The genetic heritage of some of these “sacramental wheats” lives on in farmers’ fields. CIMMYT researchers have led the way in collecting and characterizing these first wheats, preserving their biodiversity and using them as sources of traits like disease resistance and drought tolerance.

“I’d say to Bent: ‘Let’s look for the cemetery,’ ” recalls Julio Huerta, CIMMYT wheat pathologist, of his trips to villages in Mexico with his late colleague Bent Skovmand, CIMMYT wheat genetic resource expert. “And the sacramental wheats would be there, sometimes hundreds of types.”

The first wheat was brought to Mexico in 1523 around the area now occupied by Mexico City. The crop soon spread outside the central plateau with the help of Catholic monks: it traveled to the state of Michoacán in the 1530s with the Franciscans, while the Dominicans took wheat to the state of Oaxaca in 1540 and gave grains to the native inhabitants to produce flour for unleavened bread used during Roman Catholic religious ceremonies. “Still today, many church ornaments in Michoacán have wheat straw in them,” says Huerta.

Huerta and Skovmand went on sacramental wheat-gathering expeditions in 19 Mexican states. “Many people thought we were just collecting trash,” he says. “But we wanted to collect sacramental wheats before they disappeared. I’m not that surprised that some have very valuable attributes for breeding programs.”

Farmers in Mexico and elsewhere face water shortages and rising temperatures due to climate change. CIMMYT scientists are looking to sacramental wheats as one source of drought-tolerance. Field trials at the center’s Cuidad Obregón wheat research facility show some sacramental wheats have better early ground cover, quickly covering the soil and safeguarding moisture from evaporating. Others have enhanced levels of soluble stem carbohydrates which help fill the wheat grain even under drought, while some show better water uptake in deep soils thanks to their deep roots.

As farmers gain access to improved varieties or migrate to cities, sacramental wheats are disappearing from fields. With the hope of conserving these rare and valuable varieties, Huerta and Skovmand started collecting them in 1992, collaborating with the Mexican National Institute for Forestry, Agriculture, and Livestock Research (INIFAP) and supported by the Mexican Organization for the Study of Biodiversity (CONABIO). Their efforts were not in vain—10,000 samples from 249 sites in Mexico were added to the CIMMYT germplasm bank, and duplicate samples deposited in the INIFAP germplasm bank.

Only the strongest survive

The deep volcanic soils of Los Altos de Mixteca, Oaxaca, and the dry conditions in some parts of Mexico were not ideal for growing wheat. “If the wheats didn’t have deep roots and it didn’t rain, they were dead,” says CIMMYT wheat physiologist, Matthew Reynolds. The wheat genotypes that survived for centuries were perhaps the ones with drought-tolerance traits for which farmers selected. “Say the farmer had a mixture of sacramental wheats that looked reasonably similar—similar enough that he could manage them but diverse enough to adapt to local conditions,” explains Reynolds. “One year certain lines would do better than others and the farmer might harvest just the best-looking plants to sow the next year.”

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Sacramental wheats often grew in isolated rural areas, meaning that some never crossed with other varieties, leaving their genetic heritage intact. They are often tall and closely adapted to local conditions, according to Huerta, and farmers who still grow them say they taste better than modern varieties.

Reynolds is combining the old and the new—crossing improved modern cultivars with sacramental wheats to obtain their drought-tolerance attributes. “We now have several lines that are candidates for international nurseries,” he says. “They’ll go to South Asia and North Africa, and will be especially useful for regions with deep soils and residual moisture.”

Old wheats come back in style

In 2001, a new leaf rust race appeared on Altar 84, the most widely-grown wheat cultivar in Sonora State, Mexico. The CIMMYT wheat genetic resources program immediately looked for sources of resistance in the germplasm bank. The durum collection of sacramental wheats from Oaxaca, Mexico, proved extremely useful: all but one displayed minor gene or major gene resistance to the new leaf rust race, confirming that sacramental wheats are a valuable breeding resource.

CIMMYT researchers are still unlocking the potential of sacramental wheats. “We started to characterize them for resistance to leaf and yellow rust, and the collections from the state of Mexico for wheat head scab and Septoria,” says Huerta. We were surprised to find many, many resistant lines. “But until we finish characterizing all of them, we won’t know what else is there.”

For more information on sacramental wheats: Julio Huerta, wheat pathologist (j.huerta@cgiar.org) or Matthew Reynolds, wheat physiologist, ( m.reynolds@cgiar.org).

Global partnership protects Africa’s maize from parasitic plant

CIMMYT E-News, vol 5 no. 9, September 2008

sep01Looks can deceive. Striga, a deadly parasitic plant, produces a lovely flower but sucks the life and yields out of crops across Africa and Asia. A new strain of improved maize seed is helping farmers reclaim their invaded crop lands.

Striga, which typically attacks cereal crops, launches its takeover from the ground up: its deadly seedlings attach to sprouting maize plants and begin siphoning off water and nutrients before either plant emerges from the soil. The parasite also poisons its host, further stifling crop development.

Worse, Striga seems to seek out the farmers least suited to control it.

“Striga thrives in low-fertility soils, which are typically owned by the poorest farmers,” says Fred Kanampiu, CIMMYT maize agronomist. National experts estimate 14% of the maize area in sub-Saharan Africa is infested with Striga, amounting to 3.64 million hectares.

Big benefits seen for Kenya

Work by a multilateral partnership has resulted in a promising Striga control measure that has recently started moving from the laboratory to farmers’ fields. The practice is based on a type of maize with a natural mutation that allows it to resist the chemical imidazolinone—active ingredient in many herbicides. Seeds of this imidazolinone-resistant (IR) maize are coated with a herbicide and, when sown, the coated seed kills sprouting Striga, allowing the crop to flourish.

“Economic studies estimate that if a third of the Striga-infested area were planted with herbicide-coated seed, benefits to farmers in Kenya would be between USD 51 million and 102 million, after production costs,” says Kanampiu, who coordinates the Striga Management Project. “This would be topped off by a yield effect of similar magnitude, because the herbicide resistance comes in seed of improved, locally-adapted varieties.”

A complex, multilateral effort

The idea of using herbicide-resistant maize to control Striga was first proposed by the Weizmann Institute of Science in Israel in the 1990s. CIMMYT worked with that organization, as well as the Kenyan Agricultural Research Institute (KARI), BASF, the African Agricultural Technology Foundation (AATF), non-governmental organizations, and seed companies including Pioneer to develop, evaluate, and spread the practice, particularly among small-scale farmers for whom other control methods, such as spraying, are expensive or impractical. A key part of the work involved developing high-yielding, locally-adapted maize varieties that were also herbicide tolerant. The coating method was fine-tuned by Weizmann and the company Hi-Cap Formulations.

Support for more recent tests and promotion came from the German Federal Ministry for Economic Cooperation and Development (BMZ), the International Fund for Agricultural Development (IFAD), and the Rockefeller Foundation. By 2006 CIMMYT and KARI scientists had provided almost 300 herbicide-tolerant maize varieties for regional testing. Studies in randomly-selected farmers’ fields showed that with 30 grams (a little more than 1 ounce) of imazapyr herbicide per hectare as a seed coat in heavily infested fields, Striga was reduced by 81% and farmers enjoyed a 63% net return.

sept02

Striga meets its match

“The IR-maize reduces the Striga seed bank in the soil, lessening the need for future Striga control measures,” says Gospel Omanya, a Stewardship Manager from AATF, which is leading region-wide public awareness campaigns, field testing, and risk assessment. In addition, smallholder farmers who have tested the new maize and seed-coating practice on their land have obtained as much as a five-fold increase in grain yield.

Positive results like these led to the release of five IR varieties to farmers in Kenya, and nine other varieties are in performance evaluations for eventual release in Tanzania and Uganda.

More than 50,000 packages of IR-maize seed were distributed to farmers at 140 locations in Kenya for comparison with other Striga control practices. AATF surveyed more than 5,000 farmers and found they overwhelming favored the IR-maize seed. At least 10 seed companies, including Western Seed Company in Kenya and Tanseed International in Tanzania, are using IR maize and 60 tons of certified seed were marketed during 2007-2008.

“It was years of intense research and collaboration between partners dedicated to a unified objective, in addition to a willingness to invest human and financial resources, that allowed this concept to become a reality,” says Kanampiu. “The practice offers real, life-changing benefits for subsistence farmers like many in western Kenya, who tend 1.5 hectare plots of mostly maize just to feed their families. Their crops are normally so decimated by Striga that they harvest barely enough.”

Meanwhile, CIMMYT is working with the International Institute of Tropical Agriculture (IITA), a leader in the effort to identify and breed maize strains that contain genetic resistance to Striga. The aim is to offer farmers yet another way of controlling this lovely but lethal pest.

For more information, contact Fred Kanampiu (f.kanampiu@cgiar.org).

Improved maize varieties and partnerships welcomed in Bhutan

CIMMYT E-News, vol 5 no. 11, November 2008

nov02Sandwiched between China and India, the Kingdom of Bhutan is a small country that relies on maize in a big way. But maize yields are typically low due to crop diseases, drought, and poor access to seed of improved varieties, among other reasons. CIMMYT is committed to improving Bhutan’s food security by providing high-yielding, pest-resistant maize varieties to farmers and capacity-building for local scientists.

“If there is no maize there is nothing to eat,” says Mr. S. Naitein, who farms maize on half a hectare of land in Bhutan. But it’s not easy to grow, he says, citing challenges such as animals (monkeys and wild boars), insects, poor soil fertility, drought, poor access to improved seed varieties, and crop diseases like gray leaf spot (GLS) and turcicum leaf blight (TLB).

But since planting Yangtsipa—an improved maize variety derived from Suwan-1, a variety introduced from CIMMYT’s former regional maize program in Thailand—Naitein has seen a real improvement in his maize yields. The local maize variety yielded 1,700 kilograms per hectare, whereas Yangtsipa gave him 2,400 kilograms per hectare, a 40% yield increase.

“It’s no wonder that Yangtsipa is by far the most popular improved variety among Bhutanese farmers,” says Guillermo Ortiz-Ferrara, CIMMYT regional cereal breeder posted in Nepal. “Nonetheless, many local varieties of maize still occupy large areas of the country and don’t yield well.”

Maize is a staple food in Bhutan. Many people eat Tengma (pounded maize) as a snack with a cup of tea and Kharang (maize grits) are also popular. “Among the food crops, maize plays a critical role in household food security, especially for the poor,” says Ortiz-Ferrara. About 38% of the rural Bhutanese population lives below the poverty line and some 37,000 households cultivate maize. It’s estimated that 80% of this maize is consumed at the household level, according to Bhutan’s Renewable Natural Resources Research Center (RNRRC).

Leaf us alone: CIMMYT maize varieties help combat foliar diseases

Many farmers in Bhutan have been struggling with crop diseases that cut maize yields. “The recent outbreak of gray leaf spot and turcicum leaf blight affected 4,193 households and destroyed over 1,940 hectares of maize crop,” says Thakur Prasad Tiwari, agronomist with CIMMYT-Nepal. He estimates that maize is grown on 31,160 hectares in the country.

Gray leaf spot is a devastating leaf disease that is spreading fast in the hills of Bhutan and Nepal. To deal with this threat, CIMMYT sent more than 75 maize varieties with possible resistance to GLS and TLB to Bhutan in 2007. Tapping into the resources of its global network of research stations, CIMMYT sent seed from Colombia, Zimbabwe, and Mexico that was planted in GLS and TLB ‘hot spot’ locations in the country.

Ortiz-Ferrara and Tiwari then worked with Tirtha Katwal, national maize coordinator-Bhutan, and his team to evaluate these materials for their resistance.

“Together we identified the top performing lines for gray leaf spot and turcicum leaf blight which will be excellent candidates for Bhutan’s maize breeding program,” says Ortiz-Ferrara. “We are now combining their disease resistance with Yangtsipa, because we know it is high-yielding and well-adapted to Bhutan.”

Kevin Pixley, associate director of CIMMYT’s Global Maize Program, helped to develop a detailed breeding scheme or work plan for Bhutan’s national GLS breeding program. “We want to provide capacity-building for local maize scientists so they themselves can identify and breed varieties that show resistance to crop diseases,” he says.

“We feel more confident in moving forward with the next steps in our breeding program,” said Katwal. He and his team also attended a training course on seed production, de-tasselling, and pollination given by Dr. K.K. Lal, former CIMMYT maize trainee and former chief of the Seed Quality Control Center at the Ministry of Agriculture and Cooperatives (MoAC) in Nepal.

nov03

That’s what friends are for: CIMMYT, Nepal, and Bhutan collaboration

In 2001, Bhutan began collaborating on maize research with CIMMYT-Nepal, the National Maize Research Program (NMRP) of Nepal, and the Hill Maize Research project (HMRP) funded by the Swiss Agency for Development and Cooperation (SDC) in Nepal. The terrain and agro-climatic conditions of Bhutan and the Nepalese highland are similar, meaning that technologies adapted for Nepal will likely work well in neighboring Bhutan.

CIMMYT aims to facilitate regional and national partnerships that benefit farmers. For instance, during the past 7 years CIMMYT-Nepal has worked with NMRP and RNRRP to introduce 12 open-pollinated varieties (OPVs) to Bhutan. These modern varieties yield more than the local varieties whose seed farmers save to sow from year to year. Included in these 12 OPVs were several quality protein maize (QPM) varieties; these have nearly twice as much usable protein as other traditional varieties of maize.

nov04“Our CIMMYT office in Nepal has assisted Bhutan with maize and wheat genetic material, technical backstopping, training, visiting scientist exchange, and in identifying key consultants on research topics such as grey leaf spot and seed production,” says Tiwari.

Simply put, CIMMYT has useful contacts. For example, at the request of Bhutan’s Renewable Natural Resources Research Center (RNRRC), CIMMYT-Nepal put forward Dr. Carlos De Leon, former CIMMYT regional maize pathologist, to conduct a course on identifying and controlling maize diseases in February 2007. In September 2008, CIMMYT and HMRP also recommended two researchers (Dr. K.B. Koirala and Mr. Govinda K.C.) from Nepal’s NMRP to give a course on farmer participatory research that has been successful in the dissemination of new technologies.

“Ultimately, our goal is to improve the food security and livelihood of rural households through increased productivity and sustainability of the maize-based cropping system,” says Thakur Prasad Tiwari.

For information: Guillermo Ortiz-Ferrara, cereal breeder, CIMMYT-Nepal (g.ortiz-ferrara@cgiar.org) or Thakur Prasad Tiwari, agronomist, CIMMYT-Nepal (tptiwari@mos.com.np)

Biotech in Bogor

CIMMYT E-News, vol 2 no. 11, November 2005

indo2Young Indonesian researchers are reaping the benefits of collaboration with CIMMYT and at the same time helping farmers in their country.

It could be a biotech laboratory almost anywhere in the world, but this one is the Indonesian Center for Agriculture Biotechnology and Genetic Resources Research and Development in Bogor, Indonesia. What makes it remarkable is that just ten years ago Indonesia had virtually no agricultural biotechnology capacity at all. At the lab benches, in standard issue white lab coats, two of Indonesia’s brightest students, each with a strong commitment to helping their country, are doing the painstaking work that molecular biology requires and their PhD supervisors demand.

Marcia Pabendon is doing a maize diversity study, using DNA fingerprinting to identify maize germplasm from diverse sources to use as parents in a breeding program to find resistance for downy mildew and drought tolerance. These are the two most serious production constraints for maize in Indonesia, where half of all maize is grown in dry land areas. By analyzing the DNA she can be sure male and female parents in the breeding program are not closely related, which is detrimental to the hybrids.

Mohamed Azrai wants to convert local maize varieties into quality protein maize, maize with higher levels of the amino acids lysine and tryptophan, which occur at low levels in most maize and could result in protein deficiencies for anyone who relies heavily on maize in their diet. “I want my research to result in quality protein maize varieties that farmers will use,” he says. “Maybe quality protein maize can help solve the problem of protein malnutrition on my country.”

indonesia1“This is the untold story of the quiet biotech revolution going on in maize breeding in Asia,” says CIMMYT’s Luz George. “It is a successful transfer of technology from CIMMYT to developing countries which has now found direct application in the work of national program maize breeders.”

It began with the Asian Maize Biotechnology Network, AMBIONET, which was funded by the Asian Development Bank and which George coordinated. K.R. Surtrisno, the Director of the biotech center in Bogor, says the capacity enhancement the network provided was vitally important. “The network has given us, through CIMMYT, genotype data and training in mapping. Now the government of Indonesia has made a commitment to support and improve our facility, just in time to do useful work for farmers.”

His thoughts are echoed by Marsum Dahlan, the head of the Breeding and Germplasm section of the Indonesian Cereals Research institute. “When AMBIONET came we thought not only to help farmers but also to create capacity,” he says. “This technology will help us, though we must still combine it with tests in the field.”

AMBIONET and the work with CIMMYT have proven very valuable to agricultural biotechnology in Indonesia. “Even though the AMBIONET program is over, we still maintain collaboration with CIMMYT,” says Surtrisno. That is good news for Indonesia and good news for promising young researchers like Mohamed and Marcia.

For further information, contact Luz George (m.george@cgiar.org).

New Maize from CIMMYT: No “Throw-away” Lines!

CIMMYT E-News, vol 2 no. 12, December 2005

newMaizeNew, elite maize lines from CIMMYT offer enhanced nutrition and disease resistance.

CIMMYT has just released two unique maize lines that will interest breeders in developing countries. One is the first to combine maize streak virus resistance in a quality protein maize and the other is a quality protein version of one of CIMMYTs most popular maize lines. Made available every few years to partners, CIMMYT maize lines (CMLs) are among the most prized products of the Center’s maize breeding program.

“These are truly elite maize lines,” says Kevin Pixley, the Director of the Center’s Tropical Ecosystems Program. “They represent a distillation of maize genetic resources from around the world to which CIMMYT, as a global center, has privileged access. Only one of 10,000 lines might become a CML. Breeders in national programs in many developing countries look forward to new sets of these lines.”

The lines are inbred and possess excellent combining ability, which means they can be used to form either hybrids or open pollinated varieties, and so are versatile parent materials for breeders in national programs.

The new quality protein and maize streak resistant line will serve as a natural replacement for a parent in the popular Ethiopian maize hybrid, Gabisa. Maize streak virus is endemic in Africa. Severely infected plants do not produce proper cobs and nor grow to full height. Farmers will have the chance to use a hybrid with the enhanced nutritional characteristics of quality protein maize, plus built-in disease resistance.

The quality protein version of one of CIMMYT’s most successful maize lines—CML264—is virtually indistinguishable from the original parent, which is found in the pedigrees of more than a dozen commercial hybrids in Central America, Colombia, Mexico, and Venezuela. Farmers using varieties derived from it will obtain the same high yields as always, while enjoying the higher levels of grain lysine and tryptophan—two essential amino acids that improve nutrition for both humans and farm animals.

A description of the complete set of new CMLs can be found at:
https://data.cimmyt.org/

For more information contact Kevin Pixley (k.pixley@cgiar.org)

Danish Environment Ministers and Parliamentarians Visit CIMMYT

March, 2004

Denmark’s Minister for the Environment, Hans Chr. Schmidt, and members of the Environment Committee of the Danish Parliament came to CIMMYT on 4 March for a briefing on the role of agriculture and research in development, the conservation and study of genetic diversity, the potential of biotechnology, and biosafety issues. They were accompanied by Søren Haslund, Ambassador of the Government of Denmark to Mexico. During their visit they were joined by Lisa Covantes, representative of Greenpeace-Mexico.

The briefing ended with a short tour of CIMMYT’s laboratory, greenhouse, and genebank facilities. In the laboratory, researchers described how biotechnology tools increasingly facilitate the study and use of genetic resources. As one example, they presented a “maize family tree” developed on the basis of genetic analyses that assess the extent to which maize varieties and races from throughout the world are genetically similar or quite distinct. The visitors saw transformed maize and wheat plants growing in the biosafety greenhouse. In CIMMYT’s genebank, where some of the world’s largest collections of maize, wheat, and related species are held in trust for humanity, the visitors learned how these genetic resources are used to develop new varieties. They heard about CIMMYT’s work in Mexico to understand how traditional farmers manage maize diversity on the farm, and then visited one of the cold storage vaults where seed is kept.

Denmark is a world leader in its strong and thoughtful commitment to reducing poverty in developing countries through economic growth and environmentally sustainable development. The visit of the Danish delegation provided a welcome opportunity to exchange views on the role of public agricultural research for development.

The visiting members of the Environment Committee of the Danish Parliament included Eyvind Vesselbo, Mogens Nørgürd Pedersen, Torben Hansen, Jørn Dohrmann, Elsebeth Gerner Nielsen, Keld Albrechtsen, Helge Mortensen, Lone Møller, Jacob Buksti, Inger Bierbaum, Jens Vibjerg, Helga Moos, Søren Gade, Gudrun Laub, Freddie H. Madsen, and Inger Støjberg.

1) From left to right: Eyvind Vesselbo, Minister Schmidt, and Director General Iwanaga
2) Minister Schmidt and Eyvind Vesselbo in the briefing room
3) Visiting the biotech lab
4) Visiting the genebank

Gene Flow Study Explores How Farmers Keep Maize Thriving and Changing

June, 2005

gene_photo1What role do farmers play in the evolution of maize diversity? How extensive are the farming networks and other social systems that influence gene flow? These and other questions are helping researchers to combine knowledge of the genetic behavior of plants with information on human behavior to understand the many factors that affect maize diversity.

Outside a straw and mud-walled house in rural Hidalgo, Mexico, with chickens walking around and the smell of the cooking fire wafting through the air, CIMMYT researcher Dagoberto Flores drew lines with a stick in the red earth as he explained to a farmer’s wife how maize seed should be planted for an experiment. Along with CIMMYT researcher Alejandro Ramírez, Flores was distributing improved seed in communities where they had conducted surveys for a study on gene flow.

The movement of genes between populations, or gene flow, happens when individuals from different populations cross with each other. CIMMYT social scientist Mauricio Bellon is leading a study that aims to find out the impact of farmers’ practices on gene flow and on the genetic structure of landraces. It will document how practices differ across farming systems, analyze their determinants, figure out how much farmers control gene flow, and explore gene flow’s impacts on maize fitness and diversity and on farmers’ livelihoods.

gene_photo2The farmers visited by Flores and Ramírez in early June near Huatzalingo and Tlaxcoapan, Hidalgo are from just 2 of 20 study communities spanning ecologies from Mexico’s highlands down to the lowlands. Six months earlier, when farmers in these communities responded to researchers’ survey question, they asked some questions of their own: What does CIMMYT do? How can we get seed?

The team made it a priority to give the farmers what they requested for free. They drove around in a pick-up truck with seed they had acquired from CIMMYT scientists. They brought black, white, and yellow varieties that were native to the area and had been improved with weevil and drought resistance, and they also brought three CIMMYT varieties that were well adapted to a similar environment in Morelos, Mexico. They explained to the farmers how each variety should be planted in separate squares to facilitate pure seed selection.

“It’s a way to thank them, to bring something back to the communities,” says Bellon. Bringing improved germplasm for experimentation to interested small-scale farmers also allows researchers to get feedback in a more systematic way. The farmers will produce the maize independently, and they can save or discard seed from whichever varieties they choose. The team also distributed seed to farmers in Veracruz, and they plan to return after flowering and at harvest time to see how the improved seed fares compared with native varieties. That component of the project could be the beginning of further research in collaboration with farmers.

gene_photo3Farmers in the survey area of rural Hidalgo grow maize on the poorest, most steeply sloping land and struggle with soil diseases, low soil fertility, leaf diseases, low grain prices, and limited information about the use of chemical herbicides. Strong wind, rain, and hurricanes damage crops. Landslides cause erosion. Some farmers have access to roads and can transport their harvest by vehicle, but some farms located far from the communities have no highway access. The paths to farmers’ fields can be so narrow that not even cargo animals can maneuver on them with loads, so farmers must carry the harvest on their backs. Some walk 10 kilometers up and down slopes with heavy bags on their backs.

Many people grew coffee around Huatzalingo until about 10 years ago when the price plummeted. A kilogram of coffee used to fetch a price of about 20 pesos, or US$ 2. Now it fetches about five pesos, or 50 cents, per kilo, and even less during harvest time when the crop is abundant. Coffee producers in the area receive average government subsidies of between 125 and 300 pesos, or between US$ 10-30. One effect of the price drop has been increased immigration to Mexico City, to the city of Reynosa near the US border, and to lowland areas where orange cultivation is booming.

Partly in response to the crisis, farmers have started diversifying into alternative crops such as vanilla, citrus fruits, bananas, sugar cane, sesame, beans, chayote, chili peppers, and lentils, but the poor soils do not favor more lucrative crops. Maize is still the most important agricultural product in people’s diets in this area, and farmers grow it primarily for family consumption. They exchange seed with friends, neighbors, and producers in nearby communities, and they have conserved diverse native varieties.

In Mexico, maize has such great genetic diversity because farmers’ practices encourage the further evolution of maize landraces. Maize was domesticated about 6,000 years ago within the current borders of Mexico. Farmers created a variety of races to fit different needs by mixing different maize types, and they still experiment like that to this day. They save seed between seasons and trade seed with each other, and the wind carries pollen between different cultivars to create new mixtures.

“They are not artifacts in a museum,” Bellon says about landraces. “They are changing, they are moving.” Seed selection has a great impact on gene flow. Poor farmers typically exchange seed with each other, but little has been documented about the social relations that drive seed systems. With growing concerns about a loss of crop genetic diversity and a need to conserve genetic resources in recent years, it is important to understand the social principles of seed flow (and ultimately gene flow) in Mexico. The study findings will assist in exploration of the potential impact of transgenes. The researchers will develop models to try to predict how a transgene would diffuse and behave after it has been in a population for 10 or 20 years.

By learning about the relationships between farmers’ practices and gene flow, researchers hope to promote more effective policies regarding the conservation of diversity in farmers’ fields, the distribution of improved germplasm, and transgene management. Funded by the Rockefeller Foundation, the study combines social science with genetics to connect social and biological factors in maize varieties. Molecular markers will help show how much gene flow has occurred over time between the Mexican highlands and lowlands.

Researchers used geographic information systems to choose varied environments for the survey. Starting in October 2003, they sampled maize populations and interviewed the male and female heads of 20 households in each community for a total of 800 intensive interviews in 400 households. They asked about topics such as principal crops, planting cycles and methods, maize varieties, machinery and tools, infrastructure, language, seed selection, fertilizer, pest and weed control, plant height, harvest, transportation, production problems, maize uses, the sale and demand of different varieties, knowledge about maize reproduction, husk commercialization, and level of migration.

Preliminary findings have already surprised Bellon. A growing market for maize husks, which are used to wrap traditional foods such as tamales, is changing the economics of maize production. Owing to increasing demand from the US, husks have become more commercially important and profitable than grain in some communities. Facing abysmally low grain prices, the success of husk production has caused some producers to seek maize varieties with high quality husks, almost regardless of grain quality.

Bellon was also surprised at the lack of improved varieties in the areas they studied. Farmers tended to seek out and plant native varieties instead of hybrids. Some farmers thought hybrids were expensive, produced poor quality husks, and required good land, chemicals, and fertilizer, but they thought native varieties adapted easily to marginal local conditions.

The study grew out of a six-year project in Oaxaca that examined the relationship between farmers’ practices and the genetic structure of maize landraces and seed flow among farmers. It also explored the implications of transgenic technologies. However, while the Oaxaca project examined a few communities located in one environment, the idea with this follow-up study was to examine many locations in the same and different environments. In that way researchers can find out if gene flow is localized or if it crosses between regional environments. “It’s the same research model on a broader scale,” says Bellon.

For information: Mauricio Bellon

The genetic revolution continues at CIMMYT

CIMMYT E-News, vol 4 no. 8, August 2007

Faster, cheaper, more efficient: gift from DuPont helps CIMMYT scientists look for genes in wheat and maize—and gives breeders an affordable tool to help select the best.

aug07A quiet revolution is taking place in CIMMYT’s biotechnology labs. The team has just received a new generation of genotyping machines. These semi-automated work-horses will make it much easier to determine whether breeding lines contain specific useful genes. It is hoped that this will help maize and wheat breeders—through a process known as marker-assisted selection (MAS)—to make breeding more effective and get crop varieties with valuable traits to poor farmers more quickly.

Traditionally, the only way to find out whether the offspring from a particular cross have inherited useful characteristics, such as drought tolerance, disease resistance, or grain quality, has been to grow them in the field and evaluate the adult plants. MAS can speed up the breeding process, since it makes it possible to track the presence of desired genes in every generation. This does not bypass the need for field evaluation, but can greatly improve the efficiency of the process. “Field screening takes time, space, and resources, and our capacity is limited,” explains CIMMYT maize breeder Gary Atlin, “but with MAS we could use resources more effectively, zeroing in on the best lines to test in the field and filtering out those that haven’t inherited the characteristics we need.”

When researchers want to find out whether a particular line of wheat or maize has the useful version of a gene (for example, disease resistance rather than disease susceptibility), they use nearby, identifiable sections of DNA known as markers, labeled with a fluorescent dye. Different versions of markers and genes are called alleles. DNA that is close together on the chromosome tends to stay together over generations, so a specific allele of a marker will be routinely inherited alongside the desired allele of a nearby gene. Using the new capillary electrophoresis genotyping machines, the sample is forced along a narrow capillary tube under the influence of an electric current. A laser at the end of the tube detects the different alleles of the fluorescent markers, indicating to the scientist whether the sample contains the allele they want.

aug08The two ABI 3700 machines have been generously donated to CIMMYT by DuPont through its Pioneer Hi-Bred seed business, reflecting a fruitful collaborative relationship of more than a decade’s standing. Until now, CIMMYT has run most of its marker-assisted selection work on manual, gel-based electrophoresis apparatuses. In addition, analyses of genetic relationships between different wheat or maize lines have been run on older ABI genotyping machines, including two based on the previous, much slower generation of gel-based machines. The new machines can handle many more samples—96 each at a time—but it’s the savings in hands-on time that makes the real difference. “There’s no comparison,” says Marilyn Warburton, Head of CIMMYT’s Applied Biotechnology Center. “It will take us ten minutes to load one of these new machines, whereas it takes about four hours to make and load a manual electrophoresis gel.”

As well as being much quicker and less labor-intensive, capillary electrophoresis makes it possible to test for more than one marker and run more than one sample at once in each tube. By using different colors of fluorescent dye for each sample, markers for each can be distinguished, like teams of runners wearing different-colored jerseys. For maximum efficiency, scientists can also set up groups of samples to run at slightly different times, like runners set off in a staggered start. CIMMYT will even be able to develop a new type of marker, known as SNPs, which allow numerous traits to be tested simultaneously, providing more information per sample.

All of this means that the new machines have a much higher throughput capacity, and can process many more samples for the same labor input, drastically reducing the per-sample cost—currently the major constraint on use of MAS. “If MAS were significantly cheaper, I would certainly use it in maize breeding,” says Atlin. “Effectively, it lets you quickly transfer the genes you want into improved varieties. If you’re doing a backcross between a donor with a desired trait and an improved parent with good agronomic performance, you’re trying to select for one characteristic from the donor, but against all its other genes. With a number of markers, MAS makes it possible to determine exactly which progeny combine the desired gene from the donor with the good genes from the other parent. You can get results in two generations, compared to four or five normally.”

The challenge for MAS is finding genes with substantial effects, especially for complex traits such as drought tolerance in maize. Atlin believes such genes are still to be found. “In the past, donors with a single useful gene or trait but otherwise poor agronomic qualities were very difficult to use in breeding, as they introduced so much bad material. We can get rid of that useless material through MAS. That opens up the field to look for useful genes in a wider range of parents. And genotyping technology is getting cheaper and better at finding genes all the time.”

In wheat, the hunt for useful markers at CIMMYT is more advanced. “We’re working with new markers to select for nematode resistance, leaf and stem rust resistance, boron tolerance, Fusarium resistance, and grain quality,” says Susanne Dreisigacker, CIMMYT wheat molecular biologist. “Our current work is all gel-based, which means running tests sample by sample and marker by marker. Being able to run many samples at the same time will make a huge difference.”

For more information: Marilyn Warburton, molecular geneticist (m.warburton@cgiar.org)