Insecticidal activity of Lantana camara and Wedelia trilobata essential oils against Plodia interpunctella

This study assessed the potential of essential oils from Lantana camara and Wedelia trilobata as botanical control agents against Plodia interpunctella, offering a novel pest management method and a potential utilization pathway for these invasives. The insecticidal and repellent effects on larvae were assessed via the dipping and filter paper methods, respectively, while the fumigant effect on adults was tested using the sealed container method, all with the essential oils of L. camara and W. trilobata. The insecticidal effect of Lantana camara essential oil was more pronounced than that of Wedelia trilobata, with both oils exhibiting peak efficacy at the concentration of 30 uL/mL after 96-hour exposure period. The corrected mortality for L. camara and Wedelia trilobata was 89.13% and 74.64%, respectively. At a concentration of 80 uL/mL both plant essential oils showed relatively higher repellency.. However, Wedelia trilobata demonstrated superior performance, yielding the repellency of 83.996% (Grade Ⅴ) after 2 hours, notably higher than the 73.330% (Grade Ⅳ) observed for L. camara. A finding corroborated by its lower LC₅₀ value, L. camara essential oil exhibited a more potent fumigant effect than that of W. trilobata. In contrast, W. trilobata essential oil showed superior repellency; however, its efficacy in directly killing pests, whether by contact or fumigation, was consistently lower. The findings demonstrate that both invasive plants possess promising efficacy for controlling Plodia interpunctella, highlighting their potential as botanical control agents.