Further, farmers in developing countries quickly adopted these new CIMMYT-derived varieties. Over half of the 25 million hectares planted to improved maize in 1990 contained some of the center's germplasm.
CIMMYT germplasm is used by public breeding programs in all regions of the developing world. In 1990, farmers in sub-Saharan Africa planted two million hectares to maize containing CIMMYT germplasm. In Asia, 5.3 million hectares were covered by maize varieties and hybrids derived from CIMMYT germplasm; in Latin America 5.8 million hectares, and in West Asia and North Africa, 600,000 hectares.
This information is contained in a comprehensive CIMMYT study conducted by Miguel A. Lopez-Pereira and Michael L. Morris, estimating the economic impacts of the collaborative maize breeding research done by national programs in 45 developing countries and the Mexico-based center.
The study found that of the 842 maize varieties and hybrids released by public breeding programs during the 25-year period, 65 percent were improved open pollinated varieties and 35 percent were hybrids. Lopez-Pereira said the rate of releases by national maize breeding programs had intensified to the point that by 1986-1990 developing nations were releasing an average of 46 varieties and hybrids each year -- more than double the number of releases in the 1966-70 period.
The dominance of open pollinated varieties reflects CIMMYT's maize breeding emphasis until the late 1980s. In recent years hybrids have come to account for a greater proportion of releases containing CIMMYT germplasm.
The full impact of the collaboration between CIMMYT and the national breeding programs is still to come, Lopez-Pereira says. "The adoption of improved maize in the next 10 to 20 years is likely to accelerate as a result of the increased number of improved, higher yielding varieties and hybrids released annually."
More than half, or 33 million hectares, of the developing world's maize area is still planted to unimproved varieties. Morris says this reflects the difficulties-such as poor seed production and distribution-that continue to slow the adoption of improved maize germplasm by farmers. On the other hand, many developing countries are adopting agricultural policies and seed legislation to encourage maize seed industries.
Increases in maize production probably will depend almost entirely on increases in productivity, Lopez-Pereira says. One of the easiest ways to increase productivity is through the use of improved seed. Breeders thus face the task of continually developing varieties adapted to local conditions, with resistance or tolerance to biotic and abiotic stresses, especially where maize is produced under marginal conditions with little purchased fertilizer and chemical sprays against pests and diseases.
"The continued collaboration between CIMMYT and public and private breeding organizations is expected to be a key factor in meeting this challenge," Lopez-Pereira says.
(CIMMYT information material)
Return to CGIAR NEWS Table of Contents