Background Information on Maize

Maize was introduced in Africa by Portuguese explorers in the beginning of the 16th century.  It has since become Africa’s second most important food crop, behind cassava, and is grown in a wide range of environments ranging from Niger’s northern Sahel to Ethiopia’s highlands to converted forest lands of Sierra Leone.

The popularity of maize among African farmers grew slowly until the early part of the 20th century.  During World War I, the colonial government in Kenya encouraged (and provided seed for) farmers to plant maize as part of the war effort.  Maize cultivation in southern Africa was initially linked to the spread of commercial mining, as maize required less labor to grow and process than the traditional grain crops, millet and sorghum.

Although its palatability is often cited as a reason for maize’s continued popularity among rural populations of eastern and southern Africa, higher productivity and lower labor demands can probably be assumed to be at least as important.  Sorghum and millet yields in eastern and southern Africa since 1980 have averaged 765 and 729 kg/ha, respectively, compared with yields of maize over the same period of 1.19 MT/ha.  While a portion of these differences can be attributed to the different environments in which the crops are grown, even when grown under identical conditions in semi-arid southern Africa, maize was shown to yield higher.  Comparatively low labor requirements appear to be a second factor in the popularity of maize among small-scale farmers in Africa.  Increased school attendance among children who formerly performed bird-scaring chores is cited as an important factor in the shift of land out of sorghum and millet toward maize in semi-arid regions of southern Africa.

Per capita consumption of maize in Africa is highest in eastern and southern Africa.  Maize consumption in Kenya, Tanzania, Malawi, Zimbabwe, Zambia and Swaziland averages over 100 kg per year, giving maize a similar position in terms of dietary importance in those countries to rice in Asia.

Maize is mainly consumed in African households as a thick porridge, produced by hand pounding (usually preceeded by soaking) or grinding in a hammer mill, followed by boiling.  Households that depend on hand pounding generally prefer harder, flint-type varieties whose endosperm and embryo can be milled as an integral, whole grain.  Households that mill their grain generally prefer dent varieties.  Eastern and southern Africa almost exclusively grow white maize, with small pockets of yellow land races in coastal regions and southern Sudan.  West and central African households use both white and yellow maize.  Seasonally throughout Africa, a considerable amount of maize is consumed fresh, both on and off the cob, either roasted or boiled, as a snack food.

Ninety-five percent of maize produced in Africa is grown by small and medium-scale farmers who cultivate 10 ha or less.  Yields on these farms are usually low, averaging 1.2 MT/ha.  Meanwhile, the productivity range of maize farmers in Africa is perhaps wider than for any other crop.  While subsistence farmers of coastal west Africa struggle to produce 700-800 kg/ha on farms as small as half of a hectare, large scale, commercial farmers of Zimbabwe harvest some of the highest cereal crop yields in the world, regularly topping 10 MT/ha on farms larger than 1,000 ha.

The challenge of improving maize varieties for small-scale farmers in Africa appear to be centered around making the crop more resistant to foliar diseases (in humid zones of West Africa and mid-altitude zones of East Africa) and more tolerant to drought (especially in drought-prone southern Africa).  There are also widespread opportunities in reducing the time to maturity.  Longer-term, there are important opportunities in adding Striga resistance, resistance to stem borers, and increased protein content.