Potential technology and research needs for rainfed maize production in drought prone environments of Southern Africa

In southern Africa, semi-arid areas (here simply defined as areas with less than 700 mm but more than 350 mm of rainfall per annum) can be found from around 100 m to over 1,400 m above sea level. The semi-arid areas most important for maize production are found in the 800-1 ,250 m range of elevation. Maize is grown under semi-arid conditions in most parts of Zimbabwe outside of the northern central watershed, most of the interior of central southern Mozambique, in the lowveld of Swaziland, parts of eastern and northeastern Botswana, parts of southern Zambia (especially the Zambezi and Luangwa valleys) and parts of southern Malawi. In Zimbabwe, for example, based on data from the AGRITEX extension service, approximately 828,000 ha of maize was planted by smallholder farmers in semi-arid areas in 1986/87. This was approximately 64% of the total smallholder maize area in the country. The semi-arid areas are characterised by wide variation in the amount and distribution of rainfall from year to year. In most years, during parts of the maize growing season heavy storms occur and water is lost because of runoff; at other times in the season dry spells prevail. The development of technologies to cope with both the excess and shortage of water presents a major challenge.