Identifying Limiting Nutrients for Wheat Production in Halaba, Central Ethiopia

Low wheat yields in Ethiopia are largely attributed to nutrient imbalances and blanket fertilizer use without site-specific recommendations. A field experiment was conducted across eight sites in Wera Dijo District, Halaba Zone, Central Ethiopia, during the 2021 cropping season to identify the most limiting nutrients for wheat ( Triticum aestivum L.) using nutrient omission trials. The study employed a randomized complete block design with ten treatments, omitting one nutrient at a time alongside complete, NP, and control treatments. Pre-treatment soil analyses showed slightly acidic to neutral pH (6.06–6.99), medium to high organic carbon (1.85–4.19%), and low to medium phosphorus (3.10–10.94 mg/kg). Phosphorus deficiency was observed at seven of the eight sites. Nutrient treatments had a highly significant (p < 0.0001) effect on yield and yield components. Omission of nitrogen and phosphorus markedly reduced yield, with nitrogen omission causing the greatest loss, indicating N as the most limiting nutrient. In contrast, omission of K, S, Zn, and B had no significant effect. Comparable yields from NP and complete treatments highlight the adequacy of site-specific N and P fertilization. These results emphasize the need for localized nutrient management to enhance wheat productivity and fertilizer efficiency in Halaba and similar agro-ecologies.