Author : Riyanto

Summary : A field experiment was conducted to determine the effect of tillage method and nitrogen rate on some soil properties and corn response. Soil bulk density, organic matter content, soil pH, and available phosphorus in zero tillage were found similar to those in conventional tillage method, but not for infiltration rate, soil moisture content, soil resistance to cone penetrometer, and aggregate stability. The infiltration rate in zero tillage was far lower than that in conventional tillage. The infiltration rate increased with season but still remained lower than conventional tillage. Soil moisture content was comparable during the first cropping, but gradually increased significantly in the last two croppings in zero tillage. On the other hand, soil resistance to cone penetrometer was comparable during the first and second croppings, and became significantly higher in zero tillage than that in the third cropping. Soil aggregate stability in conventional tillage was higher than that in zero tillage in the first cropping, but gradually became equal during the second and third croppings. Soil organic matter content and available phosphorus were higher in the surface layer, decreased in the second layer and remained the same in the third layer. The rate of nitrogen application affected infiltration rate, soil moisture content, soil resistance to cone penetrometer and soil pH, but not soil bulk density, soil organic matter content, aggregate stability and available phosphorus. Some correlations were found between soil properties, and season or cropping also affected some of these properties. Tillage method had no effect on percent stand of corn and time of tasseling and silking.