EFFECT OF CO-APPLICATION OF RICE HUSK BIOCHAR AND UREA IN SOIL ON TOTAL NITROGEN AND GROWTH OF MAIZE (Zea mays)

Abstract

Urea is the most used nitrogen fertilizer in the world. Nitrogen losses due to volatilization and leaching are caused by overapplication. One of the best ways to maximize plant nitrogen uptake and reduce losses is to apply urea along with biochar. The purpose of this study was to evaluate the effects of rice husk biochar (RHB), together with urea, on maize development, the chlorophyll content index (CCI), plant total nitrogen (N), soil N, phosphorus (P), potassium (K), and nitrate nitrogen (NO3- N). Two soil textures (sandy loam and silty clay loam) and two biochar concentrations (1% and 2% w/w) were used in a pot experiment along with 120 kg N/ha of urea. To compare the experiment's outcomes, a control group (one without biochar or urea) was kept. The characterization of biochar verified the existence of aromatic functional groups, high ash content, high Si concentration, thermal stability, macropores, and amorphous nature. In silty clay loam soil, therefore, combined application of biochar and urea resulted in maximum plant growth and soil nutrient concentrations, including root dry weight, leaf length, leaf fresh weight, leaf CCI, soil K, P, and NO3-N. Biochar has a variety of functional groups and gaps that enhance soil health and nutrient availability, which in turn promotes maize development. Thus, the study concludes that applying urea and biochar together promotes soil growth and nutrient availability.