Influence of differently composted organic residues on the yield of maize and its residual effects on the fertility of an alfisol in Ibadan, Nigeria

The potentials of differently composted organic residues on the growth and yield of maize (Zea mays L) as well as its residual effects on the fertility were studied in a two cropping experiment. Three different compost types; Poultry manure + Leaf litter (PmLl), Poultry manure + Leaf litter + Rice straw (PmLlRs) and Poultry manure + Leaf litter + Mucuna husk (PmLlMh) and the recommended NPK fertilizer (400 kg/ha) and non fertilized control plots as check were studied. Compost types had significant effects on plant height, stem girth and yield components of the test crop as well as soil chemical and physical properties of plot with the application of PmLlMh at 1.5 t/ha consistently outperforming others. Compost rate had significant effect (p <0.01) on the growth and yield of maize. In most cases, application of 1.5 t/ha PmLlMh produced the best results. The grain yield of 3.9 t/ha produced from 1.5 t/ha PmLlMh was significantly higher than 3.2 t/ha obtained from conventional NPK fertilizer respectively. Residual effect of grain yield values obtained from 1.5 t/ha PmLlMh was also significantly (p< 0.05) higher than that of NPK values. PmLlMh at 1.5 t/ha had a significant and additive effect on soil nutrients after harvesting of maize when compared with NPK in first and second cropping. Poultry manure + Leaf litter + Mucuna husk at 1.5 t/ha could be used effectively in increasing soil fertility for maize production.