Author(s): Umeri C, Moseri H and Onyemekonwu RC
The study was carried out in Delta State, Nigeria. Soil samples were collected from nine locations within Delta State namely Agbor, Asaba and Ubulu-uku (Delta North), Abraka, Oghara-Eki, Sapele (Delta Central), Oleh, Ozoro, Patani (Delta South). Surface soils (0-15 cm) and sub-surface soils (15-30 cm) depth. These were analyzed for their physical and chemical properties. In one of the locations (Agbor) found to be deficient in nitrogen (N) and phosphorus (P) field trials on the effects of these nutrients on the performance of maize (Zea mays) were carried out. The variety ACR-89DMRESR-W was used. The design was a 4 × 4 factorial scheme fitted into a randomized complete block design given sixteen treatments combinations with three replicates. The following treatments combinations were applied N0P20kg/ha, N0P40kg/ha, N0P6okg/ha, N20P0kg/ha, N20P20kg/ha, N20P40kg/ha, N20P60kg/ha, N40P0kg/ha, N40P20kg/ ha, N40P40kg/ha, N40P60kg/ha, N60P0kg/ha, N60P20kg/ha, N60P40kg/ha, and N60P60kg/ha. The parameter measured were plant height and leaf number at 3, 6 and 9 weeks after planting (WAP), respectively. Combined application of 40 kgN/ha+40 kgP/ha significantly increased maize plant height and leaf number among all the treatments. Therefore combined application of 40 kgN/ha+40 kgP/ha is recommended for optimum growth of maize in the study area.
