COB YIELD AND GROWTH ATTRIBUTES OF EXTRA-EARLY MAIZE AS INFLUENCED BY RATES OF NPK FERTILIZER AND RESIDUAL FARMYARD MANURE IN SEMI-ARID ZONE, NIGERIA

Field experiment was conducted in 2005 and 2006 to study response of extra-early maize variety (95TZEE-Y1) cob yield and some growth parameters to four rates each of NPK (0, 40:20:20, 80:40:40 and 120:60:60 kg N:P2O5:K2O ha-1) and residual sheep manure(0, 5, 10 and 15 t FYM ha-1) in the semi-arid zone of Nigeria. Higher values for physical and chemical properties were obtained in plots supplied with manure the previous season with second year soil more fertile than the first year. Application of 120:60:60 kg N:P2O5:K2O ha-1 produced 140% and 69% more cob yield than for the control in 2005 and 2006, respectively. Plots that received applied NPK significantly recorded higher values for height, number of leaves than the control. Maize height, number of leaves (except at 8WAS in 2006), days to 50% taselling and silking (except in 2006) and cob yield positively responded to residual sheep manure. Plot supplied with 10t ha-1 had 47% and 43% more cob yield than the control in 2005 and 2006, respectively. Application of 120:60:60 kg NPK ha-1 or growing maize after pepper supplied with 10t FYM ha-1 the previous season had the highest cob yield of extra-early maize.