Effect of nitrogen fertilizer on the growth and yield of maize (Zea mays L.) under different cropping seasons in Abraka

Abstract

Maize (Zea mays L.) is an important staple in the tropics and subtropics, and has shown low productivity over the years in the tropics. This study evaluated the effect of nitrogen fertilizer on the growth and yield of maize.  The experiment was carried out at the Research Farm of the Faculty of Agriculture, Delta State University, Abraka, Nigeria. The experiment consists of five nitrogen levels (0, 40, 80, 120, and 160) and two planting seasons, early (May-August) and late (August–November), with Urea (46% N) as the Nitrogen source. It was arranged in a Randomized Complete Block Design (RCBD) with three replicates. Vegetative, yield, and yield components variables were collected and analysed using ANOVA, and means were separated using Least Significant Differences at 5% significance level. At 12 Weeks After Planting (WAP), the plant height and number of leaves varied significantly amongst the treatments and ranged from 20.14cm (0kg/ha) to 100.64 cm (160kg/ha), 20.58cm (0 kg/ha) to 112.72cm (160 kg/ha), 9.77(0 kg/ha) to 13.11 (160kg/ha), 10.22 (0 kg/ha) to 13.55 (160 kg/ha) for early and late planting seasons respectively. The 100-grain yield also varied significantly amongst the treatments and ranged from 25.02 g (0 kg/ha) to 30.67 g (120 kg/ha) in the early planting season, and from 23.64 g (0 kg/ha) to 28.31 g (120 kg/ha) in the late planting season. At treatment 120 kgha-1, the maize crop performed optimally during the reproductive, yield, and yield components stages, respectively, compared to other treatments used during the planting seasons.