Abstract:
An experiment was conducted at Osogbo Agric Farm Settelement (OAFS), Osun state, Nigeria, to investigate the effects of combined applications of poultry manure (PM) and split urea (U) fertilizer on soil and maize performance. Treatment comprised three rates of poultry manure (0, 4 and 8 t ha-1) and four urea splitting strategies (0, 120 kg ha-1 U at planting, 90kg ha-1 U at planting + 30 kg ha-1 U at 30 DAP, 60 kg ha-1 U at planting + 30kg ha-1 U at 30 DAP + 30kg ha-1 U at tasselling) resulting in twelve treatments combination. Poultry manure was applied by broadcasting two weeks before planting and worked into the soil. Two maize seed were planted per hole at 75 x 25 cm spacing and later thinned to one at two weeks after planting. Soil samples were collected from the two sites before and after the experiment and analysed for pH. Organic carbon, Nitrogen, Phosphorus, Calcium, Magnesium, Potassium, Sodium and textural analysis. Plant growth (plant height, No of leaves, stem girth and leave area) and yield parameters (No of grains per cob, weight of cob, weight of 1000 seeds) were determined. Results indicated that both urea and poultry manure and their combinations at all rate significantly (P<0.05) increases plant height, stem girth, number of leaves/plant, leaf area of maize compared with the control at both site. Highest means value of plant height were also found in treatment 12 throughout the study with the values (12.20, 66.33, 117.40, 230.26cm) at 2 ,4, 6 and 8 weeks after planting respectively at site 1. Significant (P<0.05) increases in yield parameters over control were obtained for other treatments. Of all the treatments examined, three split of urea fertilizer + 8 tons ha-1 PM gave the highest yield. The highest bulk density was recorded on treatment 1 on both sites, while increase rate of poultry manure gave the highest total porosity and moisture content. The increase rate of the combinations increases the soil pH, N, Ca, Na, Mg and B.S while treatment 1(no fertilizer) had the least value for pH, OC, OM, N, P, K, C.E.C and E.A.
