Corymbia citriodora Induces Oxidative Stress in Senna occidentalis: A Weed Management Strategy

Background and Objective: The essential oils (EOs) are known for their bioactive properties and have been widely studied for their effects on plant physiology, especially in oxidative stress responses. This study investigated the impact of the essential oil of Corymbia citriodora from the family Myrtaceae, on the stress physiology of the common wasteland weed Senna occidentalis. Materials and Methods: The essential oil of C. citriodora was extracted through hydro-distillation and seeds of S. occidentalis were treated with its various concentrations (0.1, 0.2 and 0.5 mg/mL). Oxidative stress-related parameters were studied on the seventh day after seed germination. Results: The dose-dependent increase in malondialdehyde (MDA), H₂O₂ and proline content was observed in treated plants. However, plants treated with 0.1 mg/mL of essential oil exhibited hormesis, suggesting a potential adaptive response to mild oxidative signaling. The results suggested that the essential oil of C. citriodora can be a pro-oxidant at high and a biostimulant at lower concentrations. Conclusion: Understanding how these intricate interactions work gives us a better idea of using essential oils to make plant-based bioherbicides, that are considered eco-friendly alternatives to chemical herbicides.