Fertilizer Microdosing Technology in Sorghum, Millet and Maize Production at Small-Scale Level in Africa: A Review

World population is alarmingly increasing, to feed the growing population, farmers must increase food production. Mineral fertilizer application takes the lion-share on crop productivity. However, due to the high cost of fertilizer, majority of African farmers add smaller than the recommended rate. Therefore, the farmers must adopt a technology that is environmentally friendly and minimizes dose of fertilizer keeping productivity higher than conventional fertilization. Microdosing (small and affordable quantities) fertilizer application produces higher grain yield as compared to control and banding application. Application of 0.3g NPK to 6g of NPK per pocket could increase yield of millet in range of 31.3% to 90.3 %. Similarly, application of 0.3 g NPK to 4 g NPK per pocket could increase yield of sorghum 40.9 % to 83 %. Microdosing fertilizer application is feasible and profitable than conventional fertilizer application. However, fertilizers in Africa are found in 50 kg package, which are not affordable by the poor resource farmers. The availability of fertilizer in affordable package is very crucial in expanding the technology. Moreover, the farmers must have the opportunity to inventory credit like warrantage system so that they borrow money to use it for input cost and store the crops after harvest when the price of the crops are low and resell them when the prices are higher. The use of the microdosing method brings entire changes to the existing fertilizer application methods; hence, there is a need for a strong linkage among researchers, farmers, and policy makers.