Responses of soil microbial population and lignocellulolytic enzyme activities to palm kernel shell biochar amendment

• Main Authors: Halmi, M. F. A., Simarani, Khanom
• Format: Article
• Published: Pleiades Publishing Inc 2021
• Subjects: Q Science (General); QH301 Biology; S Agriculture (General)
• Online Access: http://eprints.um.edu.my/26885/

The ameliorant effect of biochar on the physicochemical properties of tropical acidic soil has been reported in many studies. However, the study of its effect on soil microbiota in the tropical soil remained limited. A controlled 70 days microcosm experiment was conducted to assess soil microbial responses to palm kernel shell (PKS) biochar (pyrolysed at 400 degrees C) treatment in a tropical Acrisol. Biochar was added with a percentage application of 2% (w/w) (B2) and 5% (B5). The soil was destructively sampled biweekly and was analysed for physicochemical properties (pH, CEC, organic C, active C) and microbial lignocellulolytic enzyme (total cellulase, beta-glucosidase, endoglucanase, phenol oxidase, peroxidase). Total soil genomic DNA was extracted and subjected to absolute quantification of bacterial 16S rDNA and fungal ITS gene. The PKS biochar significantly improved the acidic soil condition in all measured soil physicochemical properties. Cellulolytic enzymes were significantly stimulated, while ligninolytic enzymes were unaffected. Both bacterial and fungal abundance were stimulated by PKS biochar treatment with respective increment of 221 to 334 and 208 to 277% than control. No significant changes of microbial population between the different amounts of biochar applied. The PKS biochar alters the microbial population mainly by enhancing the acidic tropical soil to a more favourable condition through elevation of soil pH and CEC.