Evaluation of Wheat (Triticum Aestivum) Varieties for Nitrogen Use Efficiency at Ambo, Central Ethiopia

Abstract

Wheat is one of the most important cereal crops in Ethiopia. However, the yield of the crop is low due to minimum use of improved varieties, low and poor soil fertility, Nitrogen rate and application of management practices. Therefore, wheat varieties for nitrogen use efficiency were evaluated during the 2018/2019 cropping season under greenhouse condition at Ambo, Central Ethiopia. A greenhouse experimental was laid out in randomized complete block design (RCBD) with three replications. The treatment consist of six wheat varieties (Hidasse, Libben, Lemu, Hulluka, Shorima and Wane) and three rates of Nitrogen (0, 34.5 and 69kg N ha-1). The results of this study showed that the main effects of N rate, varieties, and their interaction had significantly affect tiller number plant-1, fresh and dry shoot biomass, and root to shoot ratio, total N uptake, apparent N recovery efficiency, and partial N balance. Plant height, fresh and dry root weights were significantly affected only by the main effect of variety and nitrogen rate whereas they did not significantly influenced by interaction of the two factors. On the other hand, root volume was affected only by main effect of variety. The highest value of tiller number plant-1 (3.78), total N uptake (107.99kgha-1), apparent N recovery efficiency (112.56%) and partial N balance (1.44kg/kg) were obtained when Hulluka variety was applied with 34.5 kg N ha-1. The lowest tiller number per plant were recorded from Hidase, Lemu, and Shorima varieties applied with nill Nitrogen while the lowest values of apparent nitrogen recovery efficiency and partial nitrogen balance were obtained when Lemu and Shorima varieties applied with the highest nitrogen rate of 69 kg N ha-1.The lowest total N uptake were resulted from all varieties planted with no N fertilizer. On the other hand, the highest root to shoot ration (0.37) was obtained from Hulluka with nill N application while the lowest root to shoot ratio (0.15) was recorded when Hidase variety applied with 69 kg N ha-1. The highest fresh and dry shoot biomass were recorded from Wane variety planted with 69 kg N ha-1.Huluka variety resulted significantly high fresh and dry root biomass. The correlation analysis indicated that there was a significantly strong positive correlation between N uptakes of wheat cultivars with tiller number per plant, apparent N recovery efficiency and partial nitrogen balance. In conclusion, the results obtained revealed that Huluka variety applied with 34.5 kg N ha-1 significantly improved the N uptake of wheat crop which could result in higher grain yield with low fertilization condition.