Bread wheat is a vital staple crop in Ethiopia, yet yields remain critically low due to suboptimal agronomic practices. A significant problem persists in the Kambeta Zone, where low soil fertility, excessive seeding rates, and blanket fertilizer recommendations lead to poor plant stands and severe nutrient deficiencies (N, P, S, B), resulting in unacceptably low nutrient use efficiency (NUE 40%). While blended NPSB fertilizer offers a potential solution, the precise interaction between seed rates, NPSB levels, and modern wheat varieties remains unquantified, hindering the development of localized, efficient management strategies. This study therefore investigated these interactions on varieties Wane and Danda. A factorial experiment tested three seed rates (75, 100, 125 kg ha⁻¹) and four NPSB levels (0, 50, 100, 150 kg ha⁻¹). Results demonstrated that the variety Danda consistently outperformed Wane at grain yield and yield components. The optimal combination was a seed rate of 125 kg ha⁻¹ with 150 kg ha⁻¹ NPSB, which achieved the highest grain yield (5.2 t ha⁻¹) and superior NUE by significantly enhancing productive tillers, thousand-kernel weight, and harvest index. This research provides a definitive strategy to close the yield gap by synchronizing seeding density with adequate NPSB fertilization, offering farmers a precise recipe to enhance productivity and nutrient efficiency in wheat cultivation.
Manore et al. (2026) studied this question.