Effect of spirodiclofen on some biochemical parameters in Colorado potato beetle Leptinotarsa decemlineata

The Colorado potato beetle (CPB) is the most important pest of potato. In this research، effects of sublethal concentrations of spirodiclofen 240 SC were studied on lipid، carbohydrate and protein contents in CPB adults under field conditions. The experiments had a complete randomized four-factor factorial design. The four factors were the spirodiclofen concentration (0، 200، 300 and 400 µl/l)، sex (male and female)، time (3، 6 and 12 day) and number of treatment (first and second). The sugar، glycogen and lipid quantities were determined in milligram per gram of fresh weight. Results showed that spirodiclofen affected significantly total lipid، glycogen، sugar، protein and energy content (p<0. 001). The most reductions in bioenergetic resources were observed in adults retreated with the concentration of 400 μl/l sixdays after spraying. After taking into account the control، 57. 45%، 76. 38%، 72. 21%، 11. 29% and 57. 86% reduction were found in lipid، glycogen، sugar، protein and energy content، respectively. Considerable reduction in energy content indicated that chronic effects of spirodiclofen can reducing survivorship in overwintering adults of CPB.