Available Phosphorus in Soils Amended with Organic N-Enriched Composts during Periods of Incubation

Inorganic nitrogen (N) fertilizers, microbial inoculum and biologically-active substances are used to fortify composts which characteristically contain low amounts of N. The potentials organic wastes from agriculture for N enrichment were indicated by significant increase in soil while there can be fortuitous improvement the available phosphorus (P) contents on information about extent is lacking. In this study, composts: cow dung + sawdust (CDSD) poultry droppings (PDSD) enriched with meals bone (BN), blood (BM), hoof (HF) horn (HN); neem leaf (NM) tithonia (TM) attain 150, 300, 450 600 g kg-1 P was monitored at four-week intervals during 16 weeks incubation soil. Available increased all sources rates slightly week 4 but highly 8 each source, gave highest values. 15-20 20-29 mg 12 respectively. CDSDBM PDSDHF respectively short-season crops PDSDBM PDSDNM would suitable long-season crops. (29.0 kg-1) followed PDSDBN same level, 28.0 each. Although PMSDNM kg-1N had 16, values exceeding 20 also have cultivation vegetables.