Varietal response of maize to nitrogen and zinc fertilizer in Minna Southern Guinea Savanna of Nigeria

A field experiment was conducted in 2018 and 2019 seasons at the Teaching and Research Farm of the Federal University of Technology, Minna to determine the varietal response of maize to nitrogen and zinc fertilizer in Minna. The treatments included four levels of N: 0, 30, 60 and 90 kg ha-1, three levels of Zn: 0, 2.5 and 5 kg ha-1 and two varieties of maize (Oba Super 2 and Suwan-1-SR). The experimental design was a 4×3×2 factorial design fitted in a randomized complete block design with three replications. The data collected were, plant height, number of leaves, cob weight, cob length, stover yield, grain yield and 1000 grain weight. All data collected were subjected to analysis of variance and the means were separated using Duncan Multiple Range Test. Highest plant height (43.69 and 44.37 cm) were obtained in 60 and 90 kg N ha-1 treatment application respectively in year 2018 at 3 Week After Sowing (WAS), these heights were significantly different from that of control (0 kg N ha-1). Zinc (Zn) fertilization has no significant effect on maize height at all growth stage of maize in year 2018. Application of Zn produced significantly taller plants than those without Zn application at 3 and 9 WAS in 2019. The treatment 60 kg N ha-1 had significantly higher yield (27873.7 kg ha-1) than others but similar to 90 kg N ha-1 (2512.4 kg ha-1). Application of 60 kg N ha-1 increased with 12 % than the 0 kg N ha-1 on maize yield in 2019. There was response to Zn fertilization on stover and grain yields. The interaction effects were significant on stover yield. The nitrogen rate of 60 kg N ha-1 and the zinc rate of 2.5 kg were optimum for maize grain yield in Minna, both Oba Super 2 and Suwan-1-SR performed better in the study.