Performance evaluation of wheat varieties under supplementary irrigation at Gimbo district, Southwest Ethiopia

Abstract Bread wheat (Triticum aestivum L.) is an important cereal crop in Ethiopia, where supplementary irrigation offers opportunities to expand dry-season production. However, the performance of improved bread wheat varieties have not yet been evaluated under supplementary irrigation in Gimbo District. This study evaluated the agronomic performance, grain yield, disease responses, and seasonal yield stability of ten bread wheat varieties during the 2023 and 2024 dry seasons (November–February). The experiment was conducted using a randomized complete block design with three replications under supplementary irrigation. Each plot measured 3 m × 2.4 m (7.2 m²). Furrow irrigation was applied at seven-day intervals when rainfall was insufficient, with scheduling adjusted according to soil moisture and weather conditions. Data were analyzed using SAS, and grain yield performance and stability across seasons were evaluated using the genotype main effect plus genotype × environment interaction biplot model, considering the two seasons as test environments. Significant varietal differences ( p ≤ 0.05) were observed for all measured agronomic and yield traits. Mean grain yield ranged from 1,487.37 kg ha⁻¹ for Danda’a to 4,008.91 kg ha⁻¹ for Wane, followed by Kakaba (3,521.55 kg ha⁻¹) and Kingbird (3,161.01 kg ha⁻¹). Wane and Kakaba exhibited relatively low leaf rust severity and no observed stem or yellow rust. However, Danda’a showed 70.37% yellow rust severity. Kingbird displayed comparatively consistent yield performance across seasons. Wane, Kakaba, and Kingbird are well suited to supplementary irrigation in the study area. Future research should focus on multi-location testing to identify stable and widely adapted varieties.