Agricultural and Biological Research

Effect of improved Sorghum varieties to nitrogen fertilizer rates in the upper watersheds of Habru district, Northeastern Ethiopia

Mohammed Hussen*, Alemu Molla and Moges Tadesse

The productivity of Sorghum is low due to the inappropriate use of improved varieties and inadequate amount of Nitrogen (N). Therefore, a field experiment was conducted to determine the effect of Nitrogen (N) fertilizer rates and variety on Sorghum growth, yield, and yield components during the 2019 and 2020 rainy seasons at the three upper watersheds of Habru District, Northeastern Ethiopia. A Randomized Completely Blocks Designed (RCBD) in a factorial combination of N fertilizer rates (0, 46, 69, 92, and 115 kg/ha N) and Sorghum varieties (Girana-1 and Melkam) with three replications were used in this experiment. Hence, the results revealed that the application of 115 kg/ha N fertilizer at Melkam variety recorded the longest panicle length (0.31 m), maximum thousand seed weight (47.92 g), harvest index (25.87%), and total grain yields (4.10 tons/ha). On the other hand, the highest stalk yield (28.62 tons/ha) and aboveground biomass yield (32.31 tons/ha) were recorded from 115 Kg/ha N application with the Girana-1 variety. While the longest plant height (1.71 m) was recorded from the main effect of 115 kg/ha N fertilizer. Based on the results of the present study application of 115 kg/ha N fertilizer rate at Melkam variety had resulted in a total grain yield of 4.10 tons/ha with a maximum marginal increase in a net benefit of 88340.75 Birr, and a Marginal Rate of Return (MRR) 1704.01%. As a result, farmers in the study area are recommended to apply 115 kg/ha N at the Melkam variety to get an optimum and economical yield.