Title: Integrated Application of Urea and Sawdust Ash: Effect on Soil Chemical Properties, Plant Nutrients and Sorghum Performance
Abstract:Field experiment was carried out in Lanlate in rainforest zone of Southwest, Nigeria to study relative effects of combined use of Sawdust ash (SDA) and Urea (U) on soil chemical properties, nutrient s...Field experiment was carried out in Lanlate in rainforest zone of Southwest, Nigeria to study relative effects of combined use of Sawdust ash (SDA) and Urea (U) on soil chemical properties, nutrient status, growth and yield of sorghum (Sorghum bicolor (L.) Moench).The soil in the experimental site was low in nitrogen and phosphorus.The treatments were replicated three times on sorghum plant, there were six treatments; the control (no SDA, no urea), 240kg/haU, 4.5t/haSDA + 60kg/haU, 3.0t/haSDA +120kg/haU, 1.5t/haSDA+180kg/haU and 6.0t/haSDA.Combined use of SDA and urea fertilizer increased the N,P,K,Ca and Mg content of the soil.However, urea fertilizer reduced soil pH relative to control.Therefore, urea fertilizer increased soil acidity.The combined use of reduced levels of ash and urea fertilizer increased growth and yield of sorghum.The sawdust ash (SDA) and co-application of reduced levels of ash and urea increased leaf N, K, Ca and Mg status while urea alone gave highest leaf P. Urea alone at 240kg/ha (or 82kgN/ha) and 180kg/haU (111kgN/ha) + 1.5t/ha increased grain yield by 59 and 101% respectively.This work found out that SDA could be combined with urea to maximize grain yield of sorghum at 1.5t/haSDA+180kg/ha urea.This approach reduces need for urea and attendant reduction in soil pH due to the use of fertilizer.It was also found that SDA alone or combined with urea increased significantly growth of sorghum as indicated by plant height, number of leaves and stem girth.The SDA component ensured more availability of K,Ca and Mg not directly supplied by urea.Read More