Synergism of essential oils with profenophos against Spodoptera litura (Fabricius)

Two essential oils viz. Camphor, Cinnamomum camphora (L.) Sieb. and Dhatura, Datura stramonium L. were found as ‘synergist’ or ‘activator’ when combined with profenophos, when tested against Asian army worm Spodoptera litura (F.), using no choice leaf dipping method. The addition of camphor and dhatura oil reduced the concentration (LC₅₀) required to kill pest population and indicated a significant influence in increasing the toxicity against S. litura. It is evident that at 24 hours after exposure (HAE) kapoor oil and dhatura oil increased the toxicity by 2.55 and 1.07 times, respectively as compared to profenophos alone. At 48 HAE maximum synergistic effect was exhibited by kapoor oil (4.69: 1) followed by dhatura oil (1.63: 1). The combination of plant oils and insecticide exhibited added toxicity than insecticide alone.