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are often mandated to prioritize national food security above poverty alleviation, leading them to focus
on commercial farms with the highest potential productivity. Both NARSs and SMEs rely on international
centers to adapt germplasm for new environments, particularly where new traits and tools are required
to bridge significant breeding gaps. CIMMYT and IITA are the sole global suppliers of elite (sub‐)tropical
maize germplasm free from intellectual property constraints. In collaboration with national research
programs, the two centers have placed experienced breeders at strategic locations in important maizeproducing
nations—China, Colombia, Ethiopia, Kenya, India, Mexico, Nepal, Nigeria and Zimbabwe.
The centers have also established decentralized breeding networks that together exploit synergies of
scale to develop elite inbred lines adapted to globally important tropical maize mega‐environments
(Annex 4). These networks draw on the wealth of genetic resources available through the Centers and
on associated partnerships—including advanced public and private sector entities to access emerging
breeding tools—to rapidly develop new inbreds that meet local demands.
Rapid‐cycle marker‐based breeding approaches have been designed (Heffner et al. 2009) and appear
effective to increase rates of genetic gain (Eathington et al. 2007). Initial CIMMYT research has shown
that low‐cost approaches to produce double‐cross hybrids from F2 x F2 crosses are feasible (CIMMYT,
unpublished research). CIMMYT and IITA have also developed a range of topcross products involving
crosses between OPVs and inbred lines or hybrids.
Faced with the urgent need to produce much more maize on less land, this SI will identify regions with
the highest potential for productivity increases, and link with seed companies to define local germplasm
needs, to enable pre‐commercial, resource‐poor farmers to boost their productivity and move from a
subsistence to a commercial footing. In areas including sub‐Saharan Africa, rainfed South and Southeast
Asia, and Central America, where the private sector markets for hybrid maize are weak, we will work
closely with other initiatives focusing on seed sector development.
Our aim is to support regional foundation seed production centers that can supply foundation seed of
hybrid parents to emerging and existing SMEs. CIMMYT and IITA will provide parents of hybrids to the
foundation seed production centers for multiplication and distribution to the SMEs and will also
coordinate the formation of regional consortia of SMEs–to whom they will provide materials under
development and with whom they will pool testing resources. An important initiative will involve
training—staff of the companies will develop their skills in business management as well as in
production and processing of good quality hybrid seeds and marketing them to farmers. This value
proposition has a long‐term exit strategy: it will have initial support from public funds, but as markets
evolve the private sector can help defray the costs of technical support and partnerships.
Researchable issues
Methods and models to define target areas according to their relevance to sustainable
development, the environmental impact of enhanced maize production, and specific needs of
resource‐poor farmers.
Introgression of traits and alleles necessary to sustain genetic gains in highly diverse tropical
environments, in particular resistances to pests and diseases of increasing importance, along with
fertilizer use efficiency, adaptation to acid soils, and tolerance to drought, heat, and waterlogging.
Elucidation of traits associated with increased yield potential in the tropics through detailed
physiological analysis and era studies.
Design, validation, and implementation of innovative breeding strategies that sustain or increase
rates of yield gain.
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