Timing and Splitting of Nitrogen Application to Increase Tef (Eragrostic Tef (Zucc.) Trotter) Yield and Nitrogen Use Efficiency at Central Highlands of Ethiopia
Almaz Meseret Gezahegn, Sisay Eshetu, Bizuwork Tafes, Gebrekidan Feleke
Abstract
A field experiment was conducted for three consecutive years (2017 to 2019) to determine the appropriate time of nitrogen (N) fertilizer application during the crop growth cycle for increased tef productivity and nitrogen use efficiency (NUE) at central highlands of Ethiopia. A split-plot experimental design was used with two varieties and eight timings of N application at different growth stages. The results showed that variety and time of N application had a significant effect on growth parameters, NUE traits, yield, and yield components of tef at both locations. Kora variety gave higher growth parameters of tef at both locations and higher yield at Ude. Regarding time of N application, the highest yield was obtained when N was applied 50% at planting +25% at tillering + 12.5% at flag leaf +12.5% at heading, though not significantly different from other split applications at Ude. Split application increased grain yield and NUE traits as compared to full N application at once. However, at Minjar, split application didn’t show any significant difference of grain yield and NUE traits with that of full application. Partial budget analysis at Ude also showed that N application of 50% at planting +25% at tillering + 12.5% at flag leaf +12.5% at heading gave the highest net benefit and MRR. Therefore, four times (50% at planting +25% at tillering + 12.5% at flag leaf +12.5% at heading of split N fertilizer application can be recommended for higher economic yield and NUE of tef at Ude area, but split application is not advantageous at Minjar area.