Phytotoxicity and fungitoxicity of biochar-amended substrates: implications for seedling development and disease suppression

Abstract

Biochar has emerged as a promising soil amendment capable of improving physical and chemical soil properties, enhancing water retention, and promoting microbial diversity—all while contributing to a more sustainable, circular bioeconomy. However, despite these well documented benefits, key uncertainties remain regarding the potential phytotoxic effects of biochar on plant development and the influence of biochar aging within terrestrial ecosystems. Moreover, the potential of biochar to suppress fungal diseases represents an innovative and relatively unexplored avenue for its application in sustainable agriculture. This study, conducted within the framework of the SOLVO project, aims to 1) evaluate the effects of biochar-amended substrates on seedling development and potential phytotoxic responses, and 2) assess the fungitoxic and disease-suppressive properties of biochar against key fungal pathogens.