Tef is an important crop in Ethiopian production system because of its dual function both as a staple crop that improves food security and as an income-generating crop. This study had three interventions treatments on the tef production sector with selected method of substantive cost-benefit analysis, namely: Extension package, Agricultural transformation agency of Ethiopia package and the research package (which had been split in to two sub packages which were row and broadcast planting application). The objectives of this research were; to compare biological superiority of the treatments with full technology package; to conduct partial budget cost-benefit analysis of the treatments and to improve the full package of recommendations by incorporating benefits derived from the production with identification of possible ways to reduce the cost of production by constructing partial budget model. Economic constraints and opportunities for improving tef production systems in Ethiopia must be understood as the basis for research and developing interventions. This study presents the partial budget analysis (PBA) framework for the economic analysis of different tef package treatments for their benefit returns. The analysis is based on experimental data from Debre zeit research center and farmers in the Ada’a district of oromia regional state of Ethiopia. Results show that net returns of treatments extension package, research row planting package and research broadcasting package exceeded the net return of the control- ATA package by Ethiopian birr (EB) (0.32), 1.09 and 1.65, respectively (US$ 1 = EB 27.49). The decrease in cost for treatment of extension package relative to the control-ATA package was EB 1.03; the added net benefit from this treatment was EB 0.75 per unit, giving a marginal rate of return of 137%. The decrease in cost of treatment research with row planting package relative to treatment of the control-ATA package was EB 71%, while the increase in net return was EB 32.6 per unit of production, giving a marginal rate of return on the increased expenditure of 218%. The relative decreasing cost of treatment research tef broadcast planting was EB 60.7% per unit of production as compared to the control-ATA package, while the increase in net return relative to treatment the control was EB 3.38 for a marginal rate of return of 1795%. Given the high cost of capital, treatments of the control-ATA and the extension package cannot be recommended as they indicate negative benefit cost ration with (0.51) and (0.31) respectively while 1.09 and 1.65 for research row planting and broadcast planting respectively yet; the broadcast planting of tef production indicated superior in returns of EB 0.65 for EB 1 invested in the production at small scale level. In recommendation of the broadcast planting should be tested for under on - farm conditions with large number of sample in the country with spatial difference.

Keywords: Tef; Partial budget, Marginal cost, Benefit cost ratio, Yield, Variable cost