Sublethal effects of imidacloprid and clothianidin on the biological traits of predatory lacewing Chrysopa pallens (Rambur) (Neuroptera: Chrysopidae)

Imidacloprid and clothianidin are widely used insecticides for controlling piercing-sucking pests. However, their effects on non-targets insects are a major concern. Here, we evaluated the effects of sublethal concentrations of imidacloprid and clothianidin on Chrysopa pallens (Rambur) (Neuroptera: Chrysopidae), an important pest predator on many crops. Our data showed that imidacloprid and clothianidin at LD10 (0.71 and 1.42 ng active ingredient [a.i.] per insect, respectively) and LD30 (1.31 and 2.49 ng a.i. per insect, respectively) significantly increased the duration of the second instar larval stage of C. pallens. However, the duration of the third instar was prolonged only by clothianidin at LD30. At LD10, imidacloprid and clothianidin significantly increased the length of pupal stage. In addition, imidacloprid at LD30 significantly prolonged the mean generation time (T). Our results showed that imidacloprid and clothianidin prolong C. pallens developmental but had limited effects on population growth parameters. These results are expected to guide the development of integrated pest man-agement strategies.