Evaluation of Susceptibility of egg, nymph and adult of Greenhouse Whitefly Trialeurodes vaporariorum (Hem. Aleyrodidae) to Two Plant Essential Oils (Spearmint and Cumin) under Laboratory Conditions

Trialeurodes vaporariorum Westwood, 1736 is a worldwide pest that severely damages host plants especially in greenhouses. In this study respiratory toxicity of Mentha spicata and Cuminum cyminum essential oils was investigated on eggs, first instar nymphs and adults. The experiments were carried out at 27± 2 ºC, 70 ± 10% RH and 16: 8 h (light: darkness) photoperiod. The effect of these essential oils was evaluated at five concentrations. The results showed that M. spicata essence has been more toxic than C. cyminum as it caused a higher mortality (72, 86, and 83% respectively on eggs, nymphs and adults) at the highest concentration. First instar nymphs were more sensitive to the essences than both eggs and adults.