Research Article
Zeleke Teshome, Abiy Fantaye a
Abstract
A field experiment was conducted at Tendaho Sugar Factory in Ethiopia to determine economic rate of nitrogen and phosphorus for soybean-sugarcane intercropping. The experiment was laid out in randomized complete block design with three replications. Germination percentage, plant population and yield were collected for soybean. Stalk number and weight data were collected for sugarcane at the age of 8 and 14 months, respectively. Cane yield, estimated recoverable sucrose (ERS), sugar yield, and juice quality parameters such as brix (%), pol (%), and purity (%) were also determined. The soil analysis result indicated that soil of the study site was clay in texture with high pH values at the surface and subsurface layers. Moreover, the soil was low in organic carbon, total nitrogen and available phosphorous. Analysis of the variance revealed that germination percentage, plant population and yield of soybean were highly significant (p<0.01). Stalk number and weight, cane yield, ERS, and sugar yield were not significant. Juice quality parameters were also not significant. Land Equivalent Ratio (LER) was the highest, 3.52, when the intercrop fertilized with 18 kg N ha-1and 46 kg P2O5ha-1 at planting and 74 kg N ha-1at 2.5 months of cane age. However, net return (NR) and net benefit cost ratio (NBCR) were found to be the 1st and 2nd highest, respectively, when the intercrop fertilized with 18 kg N ha-1 and 46 kg P2O5ha-1 at planting (T4). Due to this treatment (T4), net return increased by 14.45% over the control (sole sugarcane without fertilizer, T8) and also cost of fertilizer reduced by 50%. It is therefore, T4, fertilizing the intercrop at rate of 18 kg N ha-1and 46 kg P2O5ha-1at planting could be the promising treatment to be recommended to Tendaho Sugar Factory.