Coccinella Septumpunctata 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 need to be evaluated on voracity of predatory beetle. The effect of Imidacloprid and Bifenthrin on predation of adult beetles 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. septumpunctata 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. The results also demonstrated non-significant differences. C. septumpunctata 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. septumpunctata was significantly affected by Imidacloprid and Bifenthrin under situation of exposure to pesticide concentrations. The study emphasized that non target beneficial species are affected due to residual spray effects leading to adverse effects on natural enemies of pest species by reducing their populations and increasing more dependency on hazardous chemical toxicants.
Key words: Pesticides; voracity; non-target species; Coccinellids
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