Journal of Earth & Environmental Waste Management
- ISSN: 3065-8799
Demeke Tamene Mitku*, Temesgen Fentahun Adamite, Abeba Hassen Sile, Mesfin Kuma Megersa and Misganawu Andualem Alamine
Irrigation water shortage is one of the limiting factors to onion productivity in Ethiopian. The experiment was conducted at Jawe
district, North West Ethiopian during 2021/22 and 2022/23 cropping season to determine the optimum rate of nitrogen rate and
irrigation level and to identify the interactive effect of nitrogen and moisture levels on yield of onion and water productivity. The
experiment was conducted in RCBD split plot design. The irrigation levels (100% ETc, 75% ETc and 50% ETc) have been be in the
main plot while nitrogen fertilizer rate treatments (0 kg/ha,23 kg/ha, 46 kg/ha, 69 kg/ha, and 92 kg/ha) have been assigned
to the sub plots. 100% ETc with 0 level of nitrogen rate was the control treatments for this experiment. Irrigation scheduling
was estimating using CropWat with 60% efficiency. Convectional furrow irrigation was used and partial flume and stop watch
were used to measure the required amount of water. Data analysis was conducted using R-software. Different irrigation levels
with the nitrogen levels had a significant (p<0.05) influence on bulb yield of onion. The highest bulb yield of 141.06q/ha was
obtained at the full application of irrigation and the lowest bulb yield of 120.76q/ha was obtained at 50%ETC irrigation level.
The highest bulb yield of 157.1q/ha was obtained at 69kg/ha nitrogen rate and the lowest average bulb yield of 101.19q/ha
was recorded from no application of nitrogen rate. The highest bulb yield of 178.89q/ha was recorded from 75%ETC irrigation
level that combined with 69kg/ha nitrogen rate and the lowest bulb yield of 84.96q/ha was obtained at 50% ETC combined with
no application of nitrogen rate. Different irrigation levels with the nitrogen levels also had a significant (p<0.05) influence on
water productivity. The highest water productivity of 5.1 kg/m3
and 4.77kg/m3
was obtained at 50%ETC and 69kg/ha nitrogen
rate respectively. The lowest water productivity of 3.00 kg/m3
was obtained at 100%ETC and 3.024 kg/m3
at no application of
nitrogen rate. The highest water productivity of 6.12kg/m3
obtained at 50% ETC combined with 92kg/ha nitrogen rate. The
lowest water productivity of 2.46 kg/m3
was obtained at 100% ETC combined with no application of nitrogen rate. Therefore,
irrigating 75%ETc combined with application of 69kg/ha nitrogen rate and 50% ETC combined with 92kg/ha nitrogen rate
were recommended to the study area to improve bulb yield of onion and to improve water productivity respectively.