A field experiment was conducted during the rainy season of 2003 to study the effects of nitrogen rates (0, 10, 20 and 30 kg/ha) and moisture conservation practices (flat bed, ridge furrow, flat bed + mulching and ridge furrow + mulching) on the soil, soil water, yield and yield components of maize ( Zea mays) grown in a rift valley in central Ethiopia. Grain yield was affected by nitrogen fertilizer levels but 1000-grain weight, total biomass, straw yield, soil temperature, soil moisture content, and infiltration rate were not affected by the nitrogen rates. Significant effects in harvest index and water use efficiency of nitrogen rates were observed only at Dera and Melkassa, respectively. Moisture conservation practices improved grain and straw yields, harvest index, and total biomass compared to the use of flat beds due to the availability of moisture. Bulk density, infiltration rate, water use efficiency, and soil moisture content were also affected by moisture conservation practices. Mulching reduced soil temperature prior to maize maturity.
