Location: China

February, 2005

The demand for maize in Asia is expected to skyrocket in the next two decades, driven primarily by its use for animal feed. In the uplands of seven Asian countries, however, demand is also increasing in the farming households who eat the maize crops they grow. CIMMYT and the International Fund for Agricultural Development (IFAD) have recently completed a project promoting food and livelihood security for upland farmers in Asia who depend on maize for food and feed.

By 2020, the International Food Policy Research Institute (IFPRI) estimates that demand for maize in all developing countries will surpass the demand for wheat and rice, with Asia accounting for over half of this growth. Responding to these predictions, teams of researchers visited farmers in the uplands of China, India, Indonesia, Nepal, the Philippines, Thailand, and Vietnam to discover ways in which maize technologies could improve livelihoods.

To further develop maize improvement recommendations, national workshops and seven publications built upon the farmer surveys. Careful planning and appropriate procedures on the part of scientists and policy makers will ensure an easier transition as farmers face the oncoming demand. A clear message that emerged from the study in Vietnam, for example, was the need to help farmers apply sustainable practices to avoid degrading natural resources—particularly in fragile, marginal settings—as the demand intensifies.

These conclusions were drawn by researchers conducting rapid rural appraisals with farmers in commercial and semi commercial systems in the up- and lowlands of these seven countries. The second stage of fieldwork entailed more in-depth participatory rural appraisals in marginal, isolated areas and involved village leaders and groups of farmers. Details on the sociological, agro-economical, environmental, and technological aspects of maize production were assembled, and the resulting publications can be viewed, downloaded, or ordered here.

In addition to CIMMYT and IFAD, the project involved collaboration with IFPRI, Stanford University, senior officials of national research programs, and ministries of agriculture.

CIMMYT E-News, vol 2 no. 9, September 2005

CIMMYT’s wheat quality lab expands and upgrades to meet growing demand of wheat for diverse food uses.

If you live in the Middle East or North Africa, you probably eat couscous. Chapati, a type of flat bread, accompanies meals in India. Many have noodles with meals in China. As varied as these foods are, they all come from wheat but require different characteristics to be considered of “good quality”—so that the wheat will mill and bake well for the desired preparation. CIMMYT works to provide farmers worldwide with wheat that will be valued in their area and has recently expanded capacity to meet growing demand, which for developing countries is nearing 300 million tons of wheat per year.

“To make a wheat variety good for both the farmer and the eater, you need to consider yield, disease resistance, and quality,” says Roberto J. Peña, Head of Grain Quality at CIMMYT. Peña works with breeders at CIMMYT and national programs all over the world to test wheat quality. Traits such as yield and disease resistance are obvious at harvest, but examining quality traits such as starch content and elasticity require complex and time-consuming tests. These difficult tasks have become easier with a new laboratory and upgraded technologies.

To reduce the time it takes to screen for quality traits, CIMMYT has equipped a quality laboratory in Ciudad Obregon in northwestern Mexico, in addition to the lab at headquarters. Now thousands of wheat lines can be screened for quality immediately after being harvested in Obregon. CIMMYT wheat breeders can see the results before they plant the next round of wheat lines. Looking at desirable quality traits much earlier in the breeding process will save time, money, and plot size as it will be easier for breeders to plant only wheat with high quality and all of the other traits they are looking for.

Peña intends to make more use of techniques like near infrared spectroscopy (NIR) analysis and marker-assisted selection (MAS) to enhance the efficiency of quality testing. “By screening thousands of lines quite simply, we are able to have a clear vision of what wheat lines aren’t going to be useful—we’re implementing modern technologies for improving end-use and nutritional quality,” he says.

Near infrared spectroscopy can be used to evaluate grain texture, starch, protein, elasticity, and mineral content. By looking into these attributes it is possible to determine whether the environment or crop management influenced the quality—all of this without the effort of milling the wheat into flour, making dough, and finally baking it. When the tests are complete, the same grain can be planted and the breeder knows what to expect.

By using MAS data from CIMMYT’s molecular biology lab, Peña and his team can take a glimpse at a particular wheat line’s DNA to determine if particular genes are present or absent. They can also see what genes have a more relevant role in defining quality, as well as tell if wheat carries high or low levels of protein. For example, if wheat has high levels of protein, it will be more elastic. In the future, they hope to start testing for the presence of specific genes associated with milling efficiency and starch properties.

By continuing to select for quality, CIMMYT hopes to enable farmers to grow wheat for quality food, whether it be couscous, chapati, or sliced bread.

For further information, contact Roberto J. Peña (j.pena@cgiar.org).

CIMMYT E-News, vol 2 no. 10, October 2005

A new genomic map that applies to a wide range of maize breeding populations should help scientists develop more drought tolerant maize.

Throughout the developing world, drought is second only to soil infertility as a constraint to maize production, and probably reduces yields worldwide by more than 15 percent (more than 20 million tons) annually. Lines have now been drawn on a new battleground: a map of the chromosomes that shows important areas that help maize resist drought.

Of the world’s three most important cereal crops (rice, wheat, and maize), maize has the most complex genetic structure. As maize has been bred and adapted to many different growing environments, selection has produced a crop that contains significant differences in levels of genetic diversity. But many genes and genetic sequences should be the same or similar. Scientists are hopeful that genetic traits for drought tolerance can be found in such shared genomic sections, across a wide range of tropical maize types. A new consensus map of genes across maize populations may be the key to identifying universal genetic “hot spots,” those genomic regions that confer drought tolerance in diverse settings to varying degrees.

“Are there any regions in the maize genome that come out as ‘hot spots’?” Jean-Marcel Ribaut and his team have asked. Known to scientists as quantitative trait loci (QTL), these regions tell scientists approximately where the genes determining a particular plant trait are located. The QTL is not a gene itself but a genomic region in which genes of interest are probably located. Prior genomic maps of QTLs for drought tolerance in tropical maize applied only to specific maize lines or populations. The CIMMYT team and partners have developed a single map that combines available drought QTL data from many trials of different tropical maize types in diverse environments. “Having all the QTL information integrated into a single map should allow us to identify the outstanding genomic regions involved in drought tolerance,” Ribaut says.

Scientists have measured drought related traits such as ear number, chlorophyll, and carbohydrate content of maize plants in the field, and have extracted and analyzed DNA from the same plants in order to plot the traits on the genomic maps. Ribaut, now Director of the Generation Challenge Programme, and CIMMYT molecular geneticist Mark Sawkins hope to link the traits they measured in the field with regions in the maize DNA.

“The idea is ambitious,” says Ribaut, “for it should allow maize breeders to select the right parents for drought tolerant maize by ensuring they have these important regions on their genome.”

With funding from the Rockefeller Foundation, members of the project team will give courses on this approach in to NARS scientists in Kenya and China over the coming months.

For further information, contact Jean-Marcel Ribaut (j.ribaut@cgiar.org) or Mark Sawkins (m.sawkins@cgiar.org).