Effects of Post - Treated and Incubated Gliricidia Biochar Samples on the Growth of Maize Seedlings

Biochar (pyrolyzed biomass) has been shown to have potential in increasing crop yield. There is, however, a dearth of information in Nigeria on the effect of post-treated biochar samples on plant growth in different soil types. The objective of this study was to investigate the effectiveness of nutrient-enhanced and incubated Gliricidia biochar on the growth of maize plant. A pot experiment was conducted in the screen house of Bowen University, Iwo Nigeria to examine the response of maize seedlings to Gliricidia biochar that was post-treated either with urea/bone ash or 15:15:15 NPK fertilizer at ratio 7:1(biochar : nutrient source, w/w). The post-treated biochar samples were incubated for 0, 14, 28 and 56 days. The treated/incubated biochar samples, untreated biochar sample and poultry manure were applied at the rate of 10 t/ha while urea/bone ash and 15:15:15 NPK inorganic fertilizer were applied at 90 kg N/ha. Maize plants were grown for eight weeks in top soil (30 cm) collected from an Oxisol in the University Teaching and Research Farm. Irrespective of incubation period and post-treatment type, maize seedling height, stem diameter, leaf production and total dry weight increased significantly (p<0.05) in all treatments having post-treated biochar materials over the non-treated control.The longer the incubation period, the more beneficial was the effect of NPK post-treated biochar on maize growth while the opposite was true for urea/bone ash-treated biochar sample NPK post-treatment of Gliricidia biochar was significantly superior to urea/bone ash post-treatment in tegrms of plant parameters.