INFLUENCE OF NITROGEN FERTILIZER RATE AND ITS TIME OF APPLICATION ON PRODUCTIVITY OF MAIZE (ZEA MAYS L.) IN HADERO TUNTO DISTRICT, KAMBATA TAMBARO ZONE SOUTHERN ETHIOPIA

Abstract

The study was conducted in Hadero Tunto District, Kambata Tambaro Zone, Southern Ethiopia during the main cropping season of 2019 to investigate optimum nitrogen fertilizer rate and its time of application to increase the productivity of maize crops. Soil fertility depletion and poor nutrient management are the major factors contributing to the low productivity of the crop.  The treatments consisted of two factors, namely, four levels of nitrogen rates and five different application times. The experiment was laid in a randomized complete block design (RCBD) in factorial arrangements with three replications. The analysis of variance showed that the maximum grain yield (6.417 t ha^-1) was obtained with the highest nitrogen fertilizer rate (200 kg ha^-1) which applied 1/3 at planting + 2/3 at knee height time. While the least value (4.413 t ha^-1) was recorded in plots that receive (50 kg ha^-1) which applied 1/3 at planting + 2/3 at near taseling. Like grain yield, the total biomass yield of maize also increased linearly with an increase in nitrogen fertilizer rates. Thus, the results suggested that the use of the high amount of nitrogen fertilizer rate with an appropriate time of application was increased the yield of maize in the study area.