Abstract

Despite the extensive area coverage of cereals in Ethiopia, their national productivity is below the average for world yield productivity. Analyzing the yield gap, i.e. the difference between yield potential and the actual yield is essential to explore intervention options that can minimize the yield gap. Therefore, this paper is aimed at estimating the yield gap and mapping its spatial variation for bread wheat and malt barley production in southeastern parts of Ethiopia. The process-based Decision Support System for Agro-technology Transfer (DSSATv4.7.5) crop model was calibrated for two wheat varieties (Hidase and Ogolcho) and one barley variety (Ibon) and used to estimate the potential yield. Potential yield was calculated for each selected reference weather station, and compared with the corresponding actual yields achieved by farmers averaged at district level to estimate the yield gap. The model simulated the highest potential yields of 7 and 6.3 t/ha respectively for the Hidase and Ogolcho varieties at the Dinsho site. In contrast, the lowest yield was simulated at Ziway-Dugda (4.9 t/ha) for Hidase and Merti (4.4 t/ ha) for Ogolcho varieties. Moreover, the highest yield gap (78%) was determined at Amigna and the lowest yield gap (26%) was determined at Lemu and Bilbilo district for malt barley. Generally, the yield gap analysis revealed high yield gaps and spatial variation across study sites for both crops.