Yield Response of Maize to Integrated Soil Fertility Management on Acidic Nitosol of Southwestern Ethiopia

Abstract

A B S T R A C T Poor crop productivity, high cost of inorganic fertilizers and low crop response to inorganic fertilizers are major problems that affect sustainability of crop production in Southwestern Ethiopia. Application of inorganic fertilizers at rates much below the recommendation, which is mainly due to the limited economic capacity of smallholder farmers, has become the underlying cause of poor crop productivity along with the worsening soil acidity condition in the region. Hence, the effect of integrated soil fertility management on the productivity of maize was investigated on acidic nitosols of the region as a cheaper and sustainable alternative to the sole application of inorganic fertilizers. Different proportions of inorganic fertilizers, compost and Tithonia biomass were therefore tested on-farm using RCB design. Grain yield of maize (kg haG 1 ) was significantly affected by soil fertility management practices (p<0.05). Data collected in 2010 indicated that 50% recommended NP and 50% compost gave the highest grain yield of maize (4360 kg haG 1 ) compared to the control which gave the lowest yield (1920 kg haG 1 ). Similar yield response pattern was also observed in 2011. Integrated use of inorganic fertilizers and organic sources of plant nutrients has therefore, shown remarkable potential for efficient nutrient supply in maize based cropping systems on acidic nitosols of Southwestern Ethiopia. However, the potential role of various organic materials including Tithonia to ameliorate soil acidity or mitigate its effects on crop productivity need to be further investigated.