Abstract: Farmers in the semi-arid regions of West Africa face challenges related to poor crop establishment, variable rainfall, low soil fertility and a shortage of labour at times of peak demand. Farmers are generally low on resources. Given these conditions, it is important to develop farming practices that make efficient use of the available resources and reduce risks. Here, we review agricultural intensification in semi-arid West Africa using the principles of precision farming to assess the possibilities they offer. The basic idea is to create a favourable micro-environment in the planting pocket and to ensure timely sowing and weeding. In the context of precision farming in the semi-arid West Africa, this means (1) large seeds are selected, primed and treated with a mix of pesticides/fungicides. Seed priming increases yields in the order of 20 to 30%, while seed treatment increases yields by 15%. (2) Mineral fertilizers are applied; at doses as low as 0.3 g of fertilizer per pocket, they have been found to increase yields by half or more. (3) Seeds and fertilizers are distributed accurately by means of a combined planter-weeder, which can be motorized. (4) Mechanized sowing and weeding enable timely farm operations and reduce the workload. (5) Water loss is prevented by using zaï and stone bunds on soils with high run-off rates. (6) Care is taken to make use of farm resources in a targeted and efficient way. This can imply adjusting micro-doses of manure and fertilizer to crops (sorghum needs less than millet) and soil types, sequenced sowing of crops according to their vulnerability to delayed sowing and applying organic input to soils. This paper is the first to review agricultural intensification in semi-arid West Africa within the context of precision farming. It shows how a low-cost package for precision farming can be developed, which can help to increase land and labour productivity, and works with all the major field crops in the region.
Keywords: Agricultural intensification; Micro-dosing; Seed management; Pearl millet; Sorghum; Groundnut; Mechanization