Impact of Nitrogen Rate and Intra Row Spacing on growth parameters and Yield of Maize at Bako, Western Ethiopia

The yield of maize is highly sensitive to nitrogen fertilizer rates and plant spacing. The space of plant is also varied depend on crop architecture and available resources. Some recent hybrids have erected and narrow leaf nature so that providing space for growing additional crop stands to increase yield per unit area. Hybrid BH-546 is among such hybrids which has erected and narrow leaf nature, but its optimum nitrogen rate and spacing has not been determined yet. Thus, a field experiment was conducted at Bako research farm in the year 2017 to determine the optimum rate of nitrogen fertilization and intra row spacing. The experiment was laid out in a Randomized Complete Block Design in factorial arrangement with three replications. Three intra row spacing viz., 75x40 cm, 75x30 cm and 75x20 cm accommodating 33, 333, 44,444 and 66, 666 plants ha-1 respectively, with six nitrogen levels viz. 0, 23, 46, 69, 92 and 115 kgha-1 were assigned to the experimental plot by factorial combinations. Based on the results, the maximum grain yield (10,207.8 kgha-1) was obtained when the hybrid was sown at the closest intra row spacing (20 centimeters) with application of the highest rate of nitrogen (115 kgha-1). This result showed 8.9% yield advantages compared to the standard check. However, statistically similar grain yield (9887 kgha-1) was also obtained under application of 92 kilo gram nitrogen per hectare in the same intra spacing (20 cm). But application of 115 kgNha-1 on maize hybrid planted at 20 cm intra row spacing was the most profitable as compared to other combinations. However, as this experiment was conducted for one season and in one location, the comprehensive recommendation could be drawn by investigating at more locations over years for this hybrid maize.