Optimizing Rates of Blended Fertilizer for High Yield and Agronomic Use Efficiency of Tef (Eragrostis tef (Zucc.) Trotter) at Central Ethiopia

Abstract

An experiment was conducted during two consecutive cropping seasons to optimize rates of blended fertilizer for high yield and N use efficiency of tef varieties at Chefe Donsa and Alem Tena. The treatments consisted of a factorial combination of two tef varieties (recently released for the areas) and five fertilizer rates (0, 100 kg ha^-1 Diammonium Phosphate (DAP), 50 kg ha^-1, 100 and 150 kg ha^-1 NPSB. Varieties, such as Dagim and Tesfa were used for Chefe Donsa, whereas Boset and Tsedey were used for Alem Tena. The treatments were arranged following randomized complete block design in triplicate. The result showed that phenology, growth and yield parameters were highly significantly (P<0.01) influenced by the main effect of blended fertilizer rates. Higher grain yield was obtained from application of 150 kg NPSB ha^-1 fertilizer rate at both locations, but was not significantly different from the application of NPSB at rates of 100 kg ha^-1 at Chefe Donsa, and from 100 kg ha^-1 NPSB and 100 kg ha^-1 DAP at Alem Tena. Economic analysis showed that application of 100 kg ha^-1 NPSB gave the highest net benefit and acceptable marginal rate of return (MRR). Therefore, application of 100 kg NPSB ha^-1 fertilizer could be recommended for production of tef in the study areas and other areas with similar agro-ecological and soil conditions.