The Role of Potassium Silicate in Quorum Quenching Against the Virulence of Ralstonia solanacearum, the Causal Agent of Bacterial Wilt in Tomato

Abstract : Bacterial wilt caused by Ralstonia solanacearum remains one of the most destructive constraints in tomato production worldwide. The pathogen’s virulence is tightly regulated by quorum sensing (QS), which controls exopolysaccharide (EPS) biosynthesis, extracellular enzyme secretion, and biofilm formation. Targeting QS through quorum quenching (QQ) represents a promising anti-virulence strategy without imposing the selective pressure associated with conventional bactericides. This study investigated the dual role of potassium silicate as (i) a QS-interfering agent that modulates bacterial virulence traits and (ii) an inducer of host systemic resistance. Potassium silicate at 1 mM significantly reduced EPS production and biofilm formation, whereas 2 mM enhanced peroxidase activity in tomato plants. Disease severity was reduced during the early stages of infection in silica-treated plants. These findings indicate that potassium silicate attenuates bacterial wilt development through the integrated modulation of pathogen virulence and host defense responses. This study provides mechanistic insight into silicon-mediated plant protection and highlights potassium silicate as a sustainable strategy for bacterial wilt management.