Characterization and Amendment of Biochar Derived from Oil Palm Fronds for Enhanced Growth and Phytometabolites of Indica Rice

Abstract

This research examines the biochar produced from Oil Palm Fronds (OPF) and its effect on the growth and phytometabolites of indica rice. OPF biochar was characterized using Scanning Electron Microscope coupled with an Energy Dispersive X-ray Spectrometer (SEM-EDS) and an X-ray Diffractometer (XRD). The elemental composition analysis revealed that the main elements were carbon (C) at 72.17% and oxygen (O) at 20.38%. Other elements included silicon (Si), aluminum (Al), calcium (Ca), magnesium (Mg), chlorine (Cl), iron (Fe), potassium (K), sodium (Na), copper (Cu), and titanium (Ti). Moreover, the XRD pattern indicated the presence of quartz (SiO₂) and sylvite (KCl), which exhibited beneficial effects on plants. The effects of the OPF biochar on the rice growth (plant height, fresh weight, and dry weight), photosynthetic pigment contents (carotenoid, chlorophyll A and B), and antioxidant enzyme activity (peroxidase and catalase) were evaluated. Rice seedlings were cultivated in culture media treated with OPF biochar at several doses (0, 200, 400, and 800 mg/L). The growth and overall content of phytometabolites increased at each concentration of biochar, reaching a maximum at 400 mg/L, while the 800 mg/L showed adverse effects. These findings demonstrated that OPF biochar has significant potential for improving the indica rice growth and phytometabolite propagation.