Examining the Physiological and Molecular Impact of Biochar on Polyol Synthesis and Drought Resistance in Tomato Plants

Abstract This study explored the impact of biochar on plant physiological and molecular responses under water stress conditions in an agricultural context, focusing on osmotic adjustment and osmoprotection mechanisms via the accumulation of polyols such as sorbitol and ribitol. We assessed sorbitol and ribitol content, alongside the activity and expression of SORBITOL DEHYDROGENASE (SDH), in mature leaves of plants with and without biochar treatment. Our findings indicate that non-biochar-treated plants (OB) exhibited higher levels of sorbitol and ribitol as well as enhanced SDH activity and gene expression under drought conditions compared to the biochar-treated plants (WB). Specifically, SDH gene expression was 53.33% and 100% higher in the OB group than in the WB group at 75% and 45% water levels, respectively. These results suggest the potential of biochar to improve plant resilience against water stress by modulating physiological stress markers, such as polyol accumulation. The study underscores a role for biochar in enhancing drought stress tolerance, offering insights into its application for sustainable agriculture.