Fertilizer Response to the Physical Effects of Soil Compaction

The effect of fertilizer response to various levels of soil compaction on the growth, nutrient uptake and yield of wheat in an artificilly completed fine sandy loam soil was studied. Eight levels of compaction (1.11, 1.18, 1.26, 1.35, 1.44, 1.53, 1.61 & 1.70 gmlec) and two levels of fertility (control and 150 ppm N + 75 ppm P₂O₅ + 75 ppm K2P) were tried in three replications. Compacting the soil from 1.11 to 1.70 gmlec resulted in large decrease in its total and aeration porosity and hydraulic conductivity. The relationship between bulk density of soil and crop growth ornutrient uptake was found parabolic in nature. An optimum compaction of 1.35 gm/cc was recorded as most favourable for crop growth. Fertilization failed to alleviate the adverse effect of soil compaction. Fertilizer response was maximum at the optimum bulk density of 1.35 gm/cc and was considerably reduced at higher and lower compaction levels. Interaction between compaction and fertility was found significant on number of ear bearing tillers, uptake of nitrogen and phosphorus.