Performance Evaluation of Botanical Insecticide, Dayabon (SL 10%), on the Elm Leaf Beetle, Xanthogaleruca luteolla

The elm leaf beetle, Xanthogaleruca luteolla, is the most important pest of elm trees, which causes severe damages every year. Chemical control is used as one of the most important methods of management of the pest extensively. Due to the deleterious effects of chemical pesticides on non-target organisms, beneficial insects and the environment, the use of botanical pesticides would be a safe and suitable method for the pest control. In this study, the contact and feeding toxicity of a new botanical pesticide, named Dayabon (SL10%), was evaluated on the 2nd instar larvae, 3rd instar larvae and adults. A preliminary experiment was conducted to estimate concentrations to cause 20 and 80 percent mortality. The bioassay was designed to determine LC50 values of 24 h post treatments. LC50 of Dayabon was estimated to be 5154, 6272 and 3928 ppm, after spraying (leaf and insect) on the 2nd instar larvae, 3rd instar larvae and adults, respectively. Treatment of leaves caused 20%, 40% and 60% damage reduction in the 2nd, 3rd instar larvae and adults compared with control at 5000, 6000 and 4000 ppm, respectively. Findings of this study indicated the possibility of practical use of Dayabon in management of elm leaf beetle in urban landscape.