1Department of Zoology, 2Department of Statistics, University of Gujrat, Punjab, Pakistan
Abstract
Coccinella septempunctata is an important natural enemy of several pest species attacking various crops in Pakistan. Mostly pests are managed by the use of pesticides in crops and ornamentals, thus, impact of pesticides needs to be evaluated on voracity of predatory beetle. The effect of Imidacloprid and Bifenthrin on predation of adult beetles predating on Russian wheat aphid, Diuraphis noxia (Mordvilko) was evaluated under laboratory conditions (25 ± 2 ºC and 65 ± 5 % RH) at Systematics and Pest Management Laboratory, Department of Zoology University of Gujrat. The significant differences in the mortality of C. septempunctata were observed amongst control and other treatments. The adult beetles showed highest mortality (91.66 % and 83.83%) when subjected to Bifenthrin (0.7%) after 48 and 24 h of exposure, respectively. Whereas the adult beetles demonstrated highest mortality (75 % and 72.66 %) when exposed to Imidacloprid (0.7%) after 48 and 24 h of exposure, respectively. The statistical analysis yielded non-significant differences were recorded at lower concentrations of both pesticides. C. septempunctata showed lower mean predation of 20.66, 18.66 and 16 when exposed to 0.01, 0.02 and 0.03 % Bifenthrin after 24 h, respectively. The voracity of C. septempunctata was significantly affected by Imidacloprid and Bifenthrin. The study emphasized that non target beneficial species are affected due to residual insecticidal spray effects reducing their population and increasing more dependency on hazardous chemical toxicants.
