s:1121:"%T Drip irrigation: options for smallholder farmers in eastern and southern Africa 
%A Sijali I V 
%X In the dry lands of sub-Saharan Africa, water deficit is the most important environmen-tal factor limiting yields in agriculture. When irrigated, these areas can have a high yield potential because of the high solar radiation, favourable day and night tempera-ture and low atmospheric humidity, conditions that decrease the incidence of pests and diseases compared to areas in temperate zones. The key to maximizing crop yields perunit of supplied water in dry lands is ensuring that as much as possible of the available moisture is used through plant transpiration and as little as possible is lost through soil evaporation, deep percolation and transpiration from weeds. In recent years there has been growing concern at the performance of conventional irrigation systems in sub-Saharan Africa. The poor performance of irrigation projects seems to have contributed to stagnation in new irrigation development. Available data suggest that irrigation potential in the region is considerable but largely unexploited 
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