Effect of Emamectin Benzoate and Indoxacarb on Tomato Leaf Minor, Tuta absoluta Meyrick (Lep.: Gelechiidae) in Laboratory Conditions

Tomato leaf miner, Tuta absoluta Meyrick is one of the most destructive pests of tomato in the world. In Iran, it was reported for the first time in 2010 from West Azerbaijan province. The pest feeds on foliage of the host plant and causes damages by reducing plant growth, creating galleries in leaves, making damage on fruits and reducing the marketable quality of the yield. Chemical method is the main measure for controlling the pest in the most parts of the world. In current study, the effects of indoxacarb and emamectin benzoate were studied against 2nd larval instar of tomato leaf miner. Rearing of the pest was carried out at 25±1 °C, 65±5% RH and a photoperiod of 16:8 (L: D) h. Bioassays were done on the larvae by leaf dipping method. Each concentration included three replications and there were 10 larvae for each replication. Treatments consisted of five concentrations for each pesticide and one for control. Insect mortality was recorded 24 h after initial exposure. In addition, sublethal effects of emamectin benzoate and indoxacarb were studied on some of biological parameters of the pest. LC50 values for emamectin benzoat and indoxacarb were 2.13 and 25.87 mg/L, respectively. Emamectin benzoat was more effective against 2nd instars larvae compared to indoxacarb. The sublethal effect study results showed that emamectin and indoxacarb reduced longevity, fecundity and pupal weight and increased larval and pupal periods. Overall, the results showed that emamectin benzoate has high potential for controlling tomato leaf miner.