Evaluation of Blended Fertilizer (NPSZnB) Rates on Yield, Nutrient Uptake, and Economic Feasibility of Maize (Zea mays L.) in Kolla Temben, Ethiopia

Maize is an important cereal crop grown and consumed in Ethiopia. However, its yield is constrained by low soil fertility and improper utilization of fertilizer. Therefore, the objective was to determine the effect of NPSZnB fertilizer rates on the yield, nutrient uptake, and economic feasibility of maize production in Bega-Sheka for the 2019 and 2020 cropping seasons. The treatments consisted of six levels of NPSZnB (0, 50, 100, 150, 200, and 250 kg NPSZnB ha−1) adjusted with N to the recommended level, and the blanket recommendation DAP (40 kg·ha −1) was also included as a positive control. The treatments were laid out in randomized complete block design with three replications. The textural class of the experimental site was silting loam with neutral soil pH. The blended fertilizer rates had a significant (p<0.05) effect on plant height, ear length, number of seeds per row, grain yield, and biomass yield. Application of NPSZnB fertilizer ranging from 150 to 250 kg·ha−1 and 200 kg·ha−1 of DAP gives the highest grain and biomass yields of maize. Hence, the highest nutrient uptake of N and P was recorded from the maximum rate of NPSZnB and P fertilizer rates, respectively. The highest marginal rate of returns of 529% was recorded with the application of 150 kg NPSZnB ha−1. Thus, the application of 150 kg NPSZnB ha−1 increases the biological and economic yield of maize, so this rate could be recommended for the study area and similar agroecologies.