Optimizing seeding rates for irrigated bread wheat (Triticum aestivum L.) varieties in the lowland area of Jawi, northwestern Ethiopia

Abstract

Bread wheat (Triticum aestivum L.) is one of the main food security crops in sub-Saharan Africa. The Ethiopian government is putting a great effort into increasing the production of bread wheat under various production systems to narrow the gap between demand and supply. There is no agronomic recommendation for wheat production produced under irrigation conditions. Thus, this study was initiated to identify the optimum seeding rates of different wheat varieties for the highest-yield and profitability in the lowland area of northwestern Ethiopia under irrigation conditions in 2020/2021. The experiment was laid out using a randomized complete block design with three replications. The treatments are five levels of seeding rates (100, 125, 150, 175 and 200 kg ha^-1) and three bread wheat varieties (Fentale-2, Kakaba and Ogelcho). Wheat yield and yield component data were statistically subjected to analysis of variance using SAS-JMP-16 software. Results revealed that the performance of wheat varieties in the lowland area of Jawi was promising irrespective of their yield differences. The study showed the highest number of total and effective tillers per unit area; and biomass and grain yield were recorded when varieties Fentale-2, Kakaba and Ogelcho were planted at a seed rate of 200 kg ha^-1, 175 kg ha^-1 and 200 kg ha^-1, respectively.The same varieties gave a grain yield of 3.99 t ha^-1, 3.47 t ha^-1 and 3.44 t ha^-1, respectively. On the other side, maximum net benefit and marginal rate of return were obtained when the variety Fentale-2 was planted at a seeding rate of 200 kg ha^-1 (NB = 65,778.8 ETB ha^-1 and MRR = 224 %) followed by the same variety at the seed rate 175 kg ha^-1 (NB = 63,402.4 ETB ha^-1 and MRR = 297 %). Thus, it can be concluded that planting variety Fentale-2 with 200 kg ha^-1 seed rate under irrigation condition is the promising agronomic practice in lowland agro-ecology of Jawi area. However, further research is also recommended by considering the appropriate planting time and the irrigation water requirement.