Locomotory behaviour of the seven‐spotted ladybird, Coccinella septempunctata, in response to five commonly used insecticides

Abstract

Coccinella septempunctata is known to actively avoid substrates treated with an insecticide containing the organophosphate dimethoate. This study examines the responses of C. septempunctata to a range of different insecticide products from three chemical classes, carbamates, organophosphates and pyrethroids. Five formulated product insecticides were compared with the active ingredients (AIs) at two different application rates and using two different spray patterns (conferring choice or no-choice designs) in a randomised block design. Coccinellids' responses differed between insecticide classes. Pyrethoid treatments significantly reduced locomotion. Organophosphates effected mixed locomotory responses, as found in previous studies. Carbamate treatments effected very few changes in locomotory activity. Similar results were found at both application rates tested and under different test designs. The results of the AI tests indicated that different components of the products were responsible for the different reactions, with the AIs being responsible for some responses but the carriers being responsible for others. Results are discussed in relation to the insecticides' modes of action and to their potential to increase the efficiency of integrated aphid control.

Dimethoate, fenvalerate and their mixture affects Hylyphantes graminicola (Araneae: Linyphiidae) adults and their unexposed offspring

“…In the present study, we used pure active ingredients rather than commercial formulations of the pesticides, which excluded any associated effects of the pesticide adjuvants on the spiders. Adjuvants may be toxic (Purcell & Schroeder, 1996) or alter animal behaviour and exposure (Thornham et al, 2008). Consequently, the effects reported in the present study may differ from those likely in field situations where commercial formulations are used.…”

“…Adjuvants may be toxic (Purcell & Schroeder, 1996) or alter animal behaviour and exposure (Thornham et al, 2008). Consequently, the effects reported in the present study may differ from those likely in field situations where commercial formulations are used.…”

Lethal effect of imidacloprid on the coccinellid predator Serangium japonicum and sublethal effects on predator voracity and on functional response to the whitefly Bemisia tabaci

“…Occurrence of such effects is likely given the multiple ways natural enemies could be exposed to pesticides. Sublethal effects can impair various key processes of natural enemies' efficacy against pests (Desneux et al 2006c(Desneux et al , 2007Thornham et al 2008;Suma et al 2009;Evans Samuel et al 2010;Arnó and Gabarra 2011;Saber 2011;Stara et al 2011;Castro et al 2012). Given the multiple possible behavioral effects, functional response of predators to prey could be impaired by pesticides (Wang and Shen 2002;Poletti et al 2007).…”

Voracity of Coccinella undecimpunctata: effects of insecticides when foraging in a prey/plant system

“…Previous studies indicated that sublethal effects of insecticides may result in an immediate disruption of predatory behaviour and a potential reduction in the efficiency of coccinellids to locate and capture their prey, since chemicals may interfere with the feeding behaviour by repellent, antifeedant or reduced olfactory capacity effects (Singh et al 2001(Singh et al , 2004Stark et al 2004Stark et al , 2007Desneux et al 2007). The behavioural responses may also alter the predator's search pattern (Thornham et al 2007(Thornham et al , 2008 by avoidance of treated surfaces or ingestion of treated prey, to minimize their contact with insecticides (Wiles and Jepson 1994;Singh et al 2001Singh et al , 2004. On the other hand, insecticides can indirectly induce modifications on the dynamic predator/prey, through changes in the state and behaviour of the aphid colony that will influence relative prey value and consequently the predator's active choice (Sih and Christensen 2001).…”