Download - Maize

What's new in this initiative?
Drought tolerance breeding will be extended to Asia and Latin America, where the combination of
increasing yields, climate change, and increasing costs of irrigation water will give rise to more
frequent large‐volume production shortfalls in maize and price variations that affect poor
consumers.
Breeding for waterlogging tolerance will be scaled up in Asia, particularly targeting areas receiving
high rainfall in the monsoon season and prone to floods during crop growth and development.
Screening under heat stress will be incorporated, based on recent studies of significant climate
change‐related impact in tropical maize, which may include heat‐related impacts on flowering and
grain filling (Lobell and Burke 2010).
Screening for combinations of stresses—particularly drought plus heat and drought plus
waterlogging—ill be initiated for the first time, because of the evidence that genotypes respond in a
non‐additive manner to combinations of stresses.
A coordinated, inter‐institutional biotic stress tolerance screening network will be established.
A systematic public pipeline for marker development for biotic and abiotic stress tolerance genes
will be implemented.
Innovative seed production systems will be developed, allowing small‐scale seed companies to
produce hybrids at low cost without the need to produce large quantities of seeds of low‐yielding
and sensitive inbred lines.
Innovative partnerships with multinational seed companies and emerging biotechnology capacities
in China, India, and Mexico will be expanded to accelerate breeding gains for the benefit of the most
disadvantaged countries and farmers, using both native and transgenic variation.
Greater focus will be placed on the search for innovative approaches to speed the dissemination of
drought‐tolerant maize into areas with weaker seed value chains.
Targeting and impact estimates
Ten farming systems with greatest losses due to drought are included in this Initiative (Figure 5). La
Rovere et al. (2010) estimated the impact of maize tolerant to drought and nitrogen stress in sub‐
Saharan Africa at 1.2 million tons annually after 10 years of research, assuming most likely rates of
adoption and conservative yield improvements of 3–20%, depending on the site and seasonal
conditions. Assuming proportional but delayed impact in Asia and Latin America (due to lack of previous
research investments) and based on maize area affected by drought (PDII Index in Hyman’s study ;
Hyman et al. 2008) and doubling impacts for the period 2020–30 in Africa, this initiative would result in
at least 1.7–4.5 million tons of additional grain valued at USD 280–815 million by 2020–30. La Rovere et
al. (2010) indicated that a monetary benefit of an additional 50% would arise from reduced yield/price
fluctuations, with a total producer benefit of USD 42–1,215 million by 2020–30.
Other issues
Gender
This strategic initiative is targeted at some of the poorest people in the developing world: smallholders
who grow maize for subsistence in drought‐prone environments, and who are unable to afford the tiny
investment in fertilizer needed to improve their maize yields above the 1–2 tons per hectare level
achievable without fertilizer in soils with low organic matter. Such farmers, primarily in sub‐Saharan
Africa, also usually have very little political influence and find it difficult to access input‐subsidy
programs. In general, women farmers in male‐dominated households have primary responsibility for
food crop production, while male household members invest their labor in more profitable cash‐crop
production or off‐farm work. Women‐headed households are usually poorer and less able to acquire
inputs than households headed by males (Doss 1999).
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