Malawi has been using one blanket fertiliser recommendation of 96 kg N and 40 kg P2O5 per hectare throughout the country regardless of soil type, climatic conditions, and farmer circumstances. Two thousand non- replicated on-farm maize fertiliser verification trials were conducted in the 1995/96 cropping season to develop alternative recommendations to the blanket recommendation. The specific objectives of the trials were (i) to determine hybrid maize response to fertiliser application, (ii) to determine the agronomic optimum fertiliser application rates for maize, and (iii) to develop appropriate area-specific fertiliser recommendations for smallholder maize production in Malawi. Of the 2,000 trial sites, 1676 were well implemented and harvested. Fertiliser application increased maize yields at all sites. The nitrogen use efficiencies (NUEs) averaged 33.9 kg grain /kg N. At the vast majority of sites the blanket fertiliser application was out-yielded by or equalled by one of the new fertiliser packages which supplied 92:21:0+4S (kg/ha of N:P205 K+S). The agronomic optimum fertiliser package rates in most areas of the country were 69:21:0+4S and 92:21:0+4S. The fertiliser packages that supplied sulphur at 4 kg/ha gave higher yields than the blanket fertiliser recommendation at more than 50% of the sites. These fertiliser verification trials have resulted in the development of new area-specific fertiliser recommendations in Malawi, which were based on an economic analysis of the trial results.

English

0103|AL-Maize Program|AGRIS 0102|AJ

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