Mechanistic understanding of biochar-induced inhibition of Bacillus megaterium growth and soil phosphorus solubilization
Liu, Yang Zhu, Lihua Zhang, Junyuan Wei, Zhuo Huang, Xuhan Steinberg, Christian EW Qiu, Hao Vijver, Martina G Zhao, Jing Peijnenburg, Willie JGM
Liu, Yang
Zhu, Lihua
Zhang, Junyuan
Wei, Zhuo
Huang, Xuhan
Steinberg, Christian EW
Qiu, Hao
Vijver, Martina G
Zhao, Jing
Peijnenburg, Willie JGM
Series / Report no.
Open Access
Type
Article
Language
en
Date of publication
Year of publication
Research Projects
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Journal Issue
Title
Mechanistic understanding of biochar-induced inhibition of Bacillus megaterium growth and soil phosphorus solubilization
Translated Title
Published in
Pedosphere 2026; 36(2):655-668
Abstract
Due to the complex composition of biochar and the potential interactions between its components, controversial results regarding its effects on soil phosphorus (P) solubilization have been reported. In this study, pinewood biochars were prepared at pyrolysis temperatures of 200 (BC200), 300 (BC300), 400 (BC400), 500 (BC500), and 600 (BC600) °C, and their dissolved (DBC200, DBC300, DBC400, DBC500, and DBC600, respectively) and particulate (WBC200, WBC300, WBC400, WBC500, and WBC600, respectively) fractions were prepared as well. An incubation experiment was conducted to investigate the effects of BCs, DBCs, and WBCs on the growth, acid (ACP) and alkaline (AKP) phosphatase activities, and metabolites and metabolic pathways of the P-solubilizing bacterium Bacillus megaterium. The results showed that the BCs, DBCs, and WBCs all negatively affected the growth and AKP activity of B. megaterium, and BC500, WBC500, BC400, and WBC400 had the greatest effects. Histidine metabolism was downregulated by BC400, and nucleotide metabolism was interfered by BC600. These negative effects of high-temperature biochars were caused by environmental persistent free radicals. In contrast, the effects of low-temperature biochars on cell proliferation and AKP activity were highly related to biochar metal contents. Using the independent action model, antagonistic effects were found between the biochar dissolved and particulate fractions in inhibiting B. megaterium growth, while these biochar fractions had synergistic effects on the inhibition of AKP activity. Overall, this study provides insights into how biochar adversely modulates microbial-mediated P solubilization.