The cultivation of Solanaceous crops, principally tomato (Solanum lycopersicum), potato (Solanum tu-berosum), and eggplant (Solanum melongena), forms a critical pillar of global food security and agricultural economics. The antimicrobial efficacy of Terminalia arjuna bark extracts against a specific complex of Solana-ceous pathogens, including Fusarium oxysporum (vascular wilt), Alternaria solani (early blight), and gram-negative bacterial surrogates for Ralstonia solanacearum. Bark samples were subjected to Soxhlet extrac-tion using a gradient of solvent polarities, petroleum ether, chloroform, acetone, methanol, and water, to fractionate bioactive constituents. Phytochemical screening confirmed the enrichment of triterpenoid saponins, hydrolysable tannins, and flavonoids in the polar acetonic and methanolic fractions. In vitro efficacy was assessed via agar well diffusion and broth microdilution assays. Results demonstrate a significant, solvent-dependent antimicrobial activity, with acetonic bark extracts exhibiting superior zones of inhibition (ZOI: 17.5–20.0 mm) against mycelial growth inhibition of fungal pathogens, comparable to synthetic standards. Minimum Inhibitory Concentration (MIC) values ranged from 0.16 to 2.56 mg/mL, indicating high potency. The mechanism of action is attributed to the synergistic disruption of fungal ergosterol. Conversely, non-polar fractions showed negligible activity, validating the critical role of polar secondary metabolites. These findings authenticate Terminalia arjuna bark as a promising source of eco-friendly, resistance-breaking bioactive compounds for Integrated Pest Management (IPM) strategies in tomato and potato cultivation.

Tomato, Potato, Eggplant, Saponins, Triterpenoid, Ergosterol