Effect of time of nitrogen fertilisation on performance of maize (Zea mays l.) of contrasting maturities following short bush fallow in a Nigerian rainforest environment

Abstract

Although short bush fallow can improve soil fertility, additional application of nitrogen may be necessary for higher yields. Even though farmers recognise the need to fertilise their maize crop to achieve high yield on sustainable basis, most farmers do not know what time to apply their fertiliser. Field trials were conducted in 2014, 2015 and 2016 growing seasons in Benin City in Nigeria rainforest to determine the performance of maize of contrasting maturities when fertilised with N at 1 week before sowing (WBS) and 2 weeks after sowing(WAS),0and3WAS,1and4WAS,2and5WASand3and6WASandazeroNControlfollowinga4- yrbushfallow.Thetrialswere laidoutinasplit-plotdesign.Earlymaturingmaizehadthehighestgrainyield (4007.9-4302.9 kg/ha) when N was applied at 1 and 4, and 2 and 5 WAS whereas late-maturing maize had highest grain yields (4647.5-5188.3 kg/ha) when fertilised 1 WBS and 2 WAS, and 3 and 6 WAS. However, grain yields(3186.2-3254.2 kg/ha) were highest for local maize when N was applied 1 WBS and 2 WAS, 2 and 5 WAS and 3 and 6 WAS. Therefore, following a short fallow period, application of N to maize may be anytime from 1 WBS to 3WASplus top-dressing 3 weeks after first application depending on the cultivar.