Nitrogen Use Efficiency in Maize (Zea mays L.) as Affected by Rates of Nitrogen Fertilizer Application on Different Soil Types in Yola, Adamawa State, Nigeria

The experiments were carried out to determine the influence of rates of nitrogen fertilizer application on different soil types that will ensure highest nitrogen use efficiency in the maize plant in Yola. Field experiments were conducted during the 2010, 2011 and 2012 cropping seasons at the Teaching and Research Farm, Modibbo Adama University of Technology Yola (Sandy-loam soil) and a private farm in Karewa area of Yola (Clay-loam soil). Treatments consists of five levels of nitrogen fertilizer (0, 40, 80,120 and 160 kg N/ha) applied as urea while phosphorus and potassium were maintained at 60 kg/ha each applied as Single superphosphate and Muriate of potash on the sandy-loam and clay-loam soils. The experiments were laid out in a Randomized Complete Block Design (RCBD) replicated three times. Parameters measured include; nitrogen accumulation/plant, nitrogen uptake efficiency, nitrogen utilization efficiency and nitrogen use efficiency. Data collected were subjected to analysis of variance (ANOVA) appropriate to RCBD and Least Significant Difference (LSD) method was used to compare the difference between means. Nitrogen uptake efficiency, nitrogen utilization efficiency and nitrogen use efficiency were significantly increased by rates of nitrogen fertilizer and soil types. The highest Nitrogen use efficiency of 72.1% was recorded on sandy-loam soil with the application of 120 kg N/ha. Sandy-loam soil has a good air and moisture retention capacity that encourages optimal and healthy maize growth when compared to clay-loam soil. Based on the findings of the study, applying the rate of 120 kg N/ha on sandy-loam soil appeared to be promising for increased nitrogen use efficiency in the maize plant and improved yield of maize in Yola and is therefore recommended to farmers in Yola.