Insecticidal Effects of Two Plant Aqueous Extracts against Second Instar Larvae of Lycoriella Auripila (Diptera: Sciaridae)

The toxicity of aqueous extracts of two plants, Nicotiana tobacum and Eucalyptus globulus were investigated against second instar larvae of Lycoriella auripila, one of the most important pests of button mushroom, using agar dilution technique. Seven concentrations of aqueous extracts of both plants were applied on second instar larvae and their mortality were evaluated after 24, 48 and 72 h. The obtained results revealed that aqueous extracts of N. tabacum and E. globulus caused 77.55 and 72.5% mortality of larvae of L. auripila at concentration of 4000 ppm after 72h, respectively. Toxicities of tobacco extract after 24, 48 and 72 h were 1.52, 1.85 and 1.70 times greather than eucalyptus, respectively. The estimated LC50 after 24, 48 and 72 h were 7316.5, 2468.5 and 2013.1 ppm for tobacco and 64870.0, 6839.5 and 3326.4 ppm for eucalyptus, respectively. These plants merit further study as potential insecticides for the control of L. auripila. Keywords—LC50, Lycoriella auripila, plants extracts, Toxicity