Insecticidal activity of the alkaloid oxymatrine on Atta sexdens workers (Hymenoptera: Formicidae)

Abstract Leaf-cutting ants of the genus Atta are traditionally controlled using synthetic insecticides, which raise environmental concerns. Botanical compounds have therefore been investigated as alternative control agents. This study evaluated the insecticidal activity of oxymatrine incorporated into toxic baits against Atta sexdens workers under laboratory conditions. Four concentrations (0.01%, 0.03%, 0.05%, and 0.1%) were tested, along with a negative control and a positive control (0.1% sulfluramid). Survival dynamics were monitored for 21 days and analyzed using survival analysis. Oxymatrine induced delayed mortality in A. sexdens workers; however, none of the tested concentrations reached the regulatory efficacy threshold required for bait-based control. These results provide baseline information on the temporal toxicity profile of oxymatrine and support further investigations focusing on formulation optimization and dose adjustment.