Abstract :
A field experiment was conducted in the Department of Crop Science Experimental Farm of the University of Calabar in 2011 and 2012 main cropping seasons to evaluate the influence of Pacesetter Organo - mineral fertilizer (OMF) rates on some soil physico-chemical properties and productivity of a local maize variety (Ikom White) grown on an Ultisol. Treatments evaluated consisted of five rates (0, 2, 3, 4 and 5 t ha-1 ) of the OMF, laid out in a randomized complete block design with three replications. Results obtained showed reduced soil acidity, depletion in total N, exchangeable Ca, Mg and ECEC, while organic Carbon and soluble Al contents increased in the post-harvest soil samples. All the OMF rates enhanced maize performance but the fertilizer was more effective in 2012 than in 2011 in the corresponding rates. However, maize plants fertilized with OMF at 5 t ha-1 were significantly taller, grew faster and attained the 50% tasseling 11 – 16 days earlier than all other rates. Plants under this treatment also produced cobs that were longer than those of the control plants by 3.5 – 12.6 cm in 2011 and 7.42 – 15.87 cm in 2012, had the highest shelling percentage (48.31 – 58.50 %), and produced the highest number of grains per cob (208.3 – 320.7). A grain yield of 2.58 t ha-1 was also recorded in 2011 and 3.20 t ha-1 in 2012 representing an increase of 0.71t ha-1 or 38 % and 2.04 t ha-1 or 176 % above the control with the application of OMF at the rate of 5 tha-1. Application of Pacesetter OMF at 5.0 t ha-1could be optimum for sustainable soil fertility maintenance and enhanced maize productivity in the Cross River Rainforest zone of Nigeria.
