Growth and Yield Response of Durum Wheat (Triticum turgidum L.) to Seed Rates and Inter-Row Spacing in Doba District, Oromia, Ethiopia

Abstract <em>Durum wheat </em>(<em>Triticum turgidum </em>L.)<em> is the most preferred crop to farmers due to its high productivity, mechanization potential, and relatively higher economic returns to other food crops grown in Ethiopia. However, its productivity is constrained by various inappropriate agronomic practices like irregular seed rate and row spacing. The field experiment was conducted at the farmers training center in Doba District, to assess the effects of seeding rate and row spacing on yield components and yields of durum wheat</em> <em>during the 2024/2025 main cropping season. Four levels of seeding rate (75, 100, 125, and 150 kg ha^-1) and three rows spacing (15, 20, and 25 cm) were tested under field conditions by using the factorial arrangement in a randomized complete block design (RCBD) with three replications.</em> <em>Data were collected on the crop parameters and analyzed using SAS version 9.4. </em><em>The results from the analysis of variance showed that most of the agronomic parameters such as plant height, spike length, total tiller, and straw yield were significantly affected by both the main effect of seeding rate and row spacing whereas days to 50% heading, days to 90% physiological maturity were showed difference by the main effect of row spacing. The interaction effect of seeding rate and row spacing were significantly affected almost all yield and yield-related parameters like the Number of productive tillers, kernels per spike, thousand seed weight, above-ground dried biomass, grain yield, and harvest index.</em><em> Hence, seeding rate of 150 kg ha^-1with 20 cm row spacing gave the highest grain yield (</em><em>3976 kg ha</em><em>^-</em><em>¹)</em> <em>of durum wheat with the highest MRR (2439.4%) and can be recommended tentatively for the study area.</em><em> However, further study has to be done under different locations and cropping seasons to exploit the recommendation of the present study.</em><em>.</em> <strong>Keywords: </strong>Durum wheat, Grain yield, seeding rates, row spacing, Productivity