Investigation on the Effect of Cholesterol Oxidase Enzyme on Oviposition and Establishment of Tomato Leaf Miner, Tuta absolut, Larvae on Three Tomato Cultivars

Tomato leaf miner, Tuta absoluta (Meyrick) is one of the key and dangerous pests of Solanaceae plants in the world, especially in Iran which is controlled by various insecticides. Excessive use of chemical insecticides can quickly lead to pest resistance. The Use of protein-based compounds such as the enzyme Cholesterol oxidase, is a good alternative to chemical insecticides. In this research, the effect of cholesterol oxidase enzyme on the oviposition preference, larval establishment and weight of pupa of Tuta absoluta was investigated. The three tomato cultivars including Newton, Izmir and Ergon were treated with cholesterol oxidase enzyme at concentrations of 0.08, 0.2 and 0.6 mg/L during three phenological stages of 30, 45 and 60 day old plants. This experiment was carried out at 16:8 D: L and 60 ± 10% relative humidity and 25 ± 8 0C under greenhouse conditions. The results showed that by increasing the enzyme concentration, the oviposition, establishment of larva and weight of male and female pupa decreased. The highest amount of oviposition was on the Ergon cultivar at 0.08 mg/L and the lowest was recorded on the Izmir cultivar at the concentration of 0.6 mg/L. The highest establishment of larvae was recorded on Newton and Ergon cultivar at the concentration of 0.08 mg/L and the lowest was recorded on Izmir variety at the concentration of 0.6 mg/L. The results indicated that the cholesterol oxidase enzyme has the ability to control and repel the tomato leaf miner.