Distribution of phosphorus (P) fractions is affected by the tillage system practiced as well as the type of fertilizer applied. A field study was conducted for two years to determine the effect of two tillage system and two fertilizer type on P distribution in a soil cropped with maize. Initial P fractionation studies showed a build-up of the recalcitrant P fraction with a low value observed for the labile P fraction. Combining zero tillage and poultry manure effectively increased the labile P fractions and this include the resin P fraction, the labile organic P fraction as well as the moderately organic P fraction. Land preparation using the conventional tillage system however increased both the conc. acid and residual P fractions, which are the recalcitrant fractions of P. Conclusively, adopting zero tillage with the application of poultry manure serves as an effective management strategy for a continuous flow of the plant available P through the build-up of the labile P fractions.
Keywords: tillage system; poultry manure; labile p fraction; non-labile p fraction
