Novel Fungicide from Waste Oil Palm Fruit Bunch for Sustainable Management of Tomato Wilt Disease Caused by Fusarium oxysporum - experimental and in silico studies

Tomato wilt, a widespread and persistent disease caused by the fungus Fusarium oxysporum , can be effectively controlled through biological approaches, promoting ecosystem sustainability and enhancing agricultural productivity and quality. This study explored the use of empty oil palm fruit bunch (EOPFB) waste as a natural fungicide to control tomato Fusarium wilt disease through in vitro, pilot scale, and molecular docking experiments. EOPFB aqueous extract showed the highest mycelium growth inhibition of 68.3 %, with the commercial fungicide Mancozeb exhibiting a moderate 42.30 % inhibition, and sterile distilled water having a negligible effect of 0.24 %. The inhibition rate varied with concentration, peaking at 72.63 % at 0.15 g/mL and dropping to 54.80 % at 0.01 g/mL. In terms of wilt disease incidence and severity, EOPFB performed best, recording the lowest incidence of 47.20 % and severity of 15.58 %. Mancozeb followed closely, with an incidence of 46.30 % and severity of 26.23 %. Sterile distilled water, on the other hand, showed the highest incidence of 76.28 % and severity of 56.17 %. Molecular docking simulations corroborated the experimental results, validating the potency of EOPFB as an inhibitor of trypsin from F. oxysporum , and identifying 2-amino-5,6-dimethyl-3 H-pyrimidine-4-one as the primary active compound responsible for the fungicidal activity. This phytochemical, abundant in the crude ethanolic extract of EOPFB, was found to have a higher binding affinity (6.1 kcal/mol) than Mancozeb (4.8 kcal/mol), at the trypsin target. These findings demonstrate the potential of EOPFB, an agricultural waste product, as a sustainable and eco-friendly solution for managing tomato Fusarium wilt disease, contributing to increased tomato production. It also highlights the potential of 2-amino-5,6-dimethyl-3 H-pyrimidine-4-one as a lead compound for the development of novel, natural fungicides, and underscores the value of EOPFB as a rich source of bioactive compounds with agricultural and biotechnological applications.