Abstract

A study was conducted at Metahara Sugar Estate in Ethiopia with the objectives to determine the optimum rates of nitrogen and compost for sugarcane production, and the effect of compost on soil chemical properties. Four levels of nitrogen (0, 46, 92, and 138 Kg /ha) and five levels of compost (0, 5, 10, 15, and 20 ton/ha) were combined in factorial arrangement. The experiment was laid out in randomized complete block design with three replications. It was conducted on clay soils (Haplic Cambisols). Soil samples were taken before and after treatment application, and analyzed for pH (1:2.5), ECe, organic carbon, total N, available P, and available K. All the cultural practices were executed as per the estate’s practice. Analysis of the soil indicated that except for pH value, all the salient soil properties including ECe, organic carbon, total nitrogen, available P, and available K were slightly increased due to compost application. Analysis of variance indicated that interaction effect between nitrogen and compost was significant (p<0.05) on stalk girth, stalk weight, cane yield, and sugar yield. Highest cane and sugar yields were obtained when 46 Kg N/ha applied with 15 ton of compost/ha. Net benefit to cost ratio was also found to be the highest, 1.12, for this combination. Therefore, 46 Kg N/ha with 15 ton of compost/ha is recommended for clay soils (Haplic Cambisols).

Keywords: Sugarcane; Compost; Filtercake; Vinasse; Nitrogen;Sugar yield