Evaluating agricultural yield and economic implications of varied irrigation depths on maize yield in semi-arid environments, at Birfarm, Upper Blue Nile, Ethiopia

Abstract

The agricultural crop that is particularly important to the world is maize, and its development is frequently impacted by a crucial factor known as moisture stress. It is crucial to understand how maize reacts to different irrigation depths, especially in dry and semi-arid locations where it has high irrigation requirements and is sensitive to water stress. Using the furrow irrigation method, an experiment at Birr Farm in the irrigation seasons of 2022–2023 examined the effects of varying irrigation depths (from 50% ETc to 150% ETc) on maize yields and related components. The experiment is set as a randomized complete block design with three replications. The outcomes showed that different irrigation depths had a substantial (P < 0.001) impact on yield characteristics. The highest grain yield, reaching 6.08 t/ha and 5.83 t/ha, occurred at 100% ETc in the second and first seasons, respectively. Similarly, the peak above-biomass yield, at 14.28 and 14.94 t/ha, was observed at 100% ETc in the second and first seasons, respectively, diminishing with further deviations in irrigation depth. From an economic standpoint, applying 100% ETc proved financially viable for small-scale farmers. Notably, utilizing a 50% ETc irrigation depth allowed for water savings of 4345.95 m3/ha, subsequently enabling the irrigation of an additional 0.43 ha, demonstrating a practical water-saving approach for downstream users in irrigation schemes, even if it was 8.9 kg m−3 yield reductions.