|SPORE Bulletin of the CTA No. 37 - February 1992 (CTA Spore, 1992, 16 p.)|
Maize was introduced into Africa between the 16th and 18th centuries, and is now the continent's premier cereal crop (40% of all cereals harvested in 1989). Kenya and southern Africa grow the most, though because of its sensitivity to drought conditions its cultivation in semi-arid zones can cause problems. In western Africa traditional crops and rice are more popular, but maize looks like being the fastest-expanding crop of the future, as long as more people can be persuaded to eat it.
Research into varietal improvement in both temperate countries and the Tropics has benefited maize more than any other cereal grown in Africa. Hybridization techniques have resulted in maize having the greatest yield potential of the dryland cereals. In Zimbabwe, harvests on the big commercial farms yield more than five tonnes per hectare. Small-scale farms have been planting hybrid varieties since 1980 and, despite fairly severe and on-going drought conditions, this has increased yields by 20%.
In the Sahel, maize has been heralded as a possible substitute for imported, or even locally-grown, rice. Rice cultivation in the Sahel requires irrigation and this demands substantial investment in equipment, maize on the other hand is a rain-fed cereal. In the Sudan there is considerable potential for rotating maize with cotton. Maize is an earlier crop than sorghum (its production cycle is 90-120 days) and so it does not disrupt cotton growing or harvesting to the same extent. Maize responds better than any other crop to the application of fertilizers and is therefore in the best position to benefit from the residual plant nutrients from the cotton crop.
The importance of dietary habits
From Senegal to Cameroon the rapid rise in cotton growing has gone hand in hand with increased maize production. In Mali the "Maize Project" launched in the late seventies by the Compagnie Malienne des Textiles has seen a five-fold increase in national production in a decade. However, this was not accompanied by a growth in market outlets and therefore after a few years the pressure to produce more maize ceased. Village flour mills were built and from 1986 part of the crop could be processed on the spot into flour and cracked corn, which is more marketable in the cities. But traditional dietary habits have doomed attempts to substitute cracked corn for rice and maize is more likely to be competitive in its own right than as a substitute for rice.
The difficulties in finding a niche for maize in the food market have led the Malian cereals company, Cerecom, to explore nonfood uses for maize, for example, the manufacture of glue or starch. The industrialized countries have gone further in developing maize as a raw material for the chemical industry, and have developed a wide range of products including fuel ethanol and a biodegradable substitute for plastic.
The future for maize
Breweries are the most promising industrial outlet for maize in Africa and in Cameroon several specialized large-scale farms, such as Borongo which grows 2,500ha of maize, have been established to meet this need. Poultry-keeping, which is expanding rapidly in Africa, is also likely to provide a profitable outlet for maize-growers.
Nevertheless, human consumption remains the largest market. Even if maize has not become the staple diet of west Africa as a whole, in countries such as Benin it is a basic dietary component. However, in Southern Africa maize now predominates, almost to the exclusion of other cereals. In Zimbabwe, even in arid zones more suited to millet and sorghum, maize has expanded disproportionately because of the extremely attractive prices offered as incentives.
In Botswana, where maize is processed industrially, it has replaced traditional crops which have to be milled by hand. In 1960 sorghum accounted for 80% of cereal consumption, but by 1981 it had dropped to 22% having been overtaken by maize.
However, maize is not really suitable for the dry climate of this country (it needs at least 700mm of rainfall per annum), and consumer demand has now led Botswana to depend heavily on South African production.
To reduce this dependency on imports, the Botswana government is encouraging development of a mechanized sorghum dehusking process. (See Spore 35).