Abstract:
The study determined nitrogen, phosphorus fertilizers and lime micro doses effects on soil chemistry and
maize performance on an acid soil smallholder farm. Treatments were micro doses (50% of recommendations)
of N (0 and 37.5 kg N ha-1), P (0 and 13 kg P ha-1) fertilizers and lime (0 and 2.26 tons lime ha-1). Nitrogen, Pfertilizers
and lime significantly (p<0.05) increased soil N, P and pH. Agronomic N-fertilizer use efficiency were
29 and 35 kg ha-1 kg-1 N-fertilizer due to 37.5 kg N and 37.5 kg N+2.26 tons lime ha-1, respectively. Grain
agronomic P-fertilizer use efficiency was 24 and 30 kg ha-1 kg-1 P-fertilizer due to 13 kg P and 13 kg P+2.26 tons
lime ha-1, respectively. N-fertilizer recovery were 47 and 50% due to 37.5 kg N and 37.5 kg N+2.26 tons lime ha-1,
respectively and P-fertilizer recovery efficiency were 14 and 16% due to 13 kg P and 13 kg P+2.26 tons lime ha-1,
respectively. Grain yield increments were 72, 27 and 12% due to 37.5 kg N, 13 kg P and 2.26 tons lime ha-1,
respectively. Therefore, N-, P-fertilizers and lime micro doses can improve maize grain yield on acid nutrient
deficient smallholder farms.
