Sublethal effects of esfenvalerate on the feeding behaviour of Tasmanian lacewing (Micromus tasmaniae) Walker [Neuroptera: Hemerobiidae] : A dissertation submitted in partial fulfilment of the requirements for the Degree of Bachelor of Horticultural Science (Honours) at Lincoln University

Abstract

Sublethal effects of the synthetic pyrethroid insecticide, esfenvalerate, on the short-term feeding behaviour of Micromus tasmaniae are investigated. The criteria used to ascertain the sublethal effect of esfenvalerate on M. tasmaniae feeding on Acyrosiphon pisum were: consumption of aphids in 24 hours; consumption of aphids over the third instar (4 days at 20-22°C); functional response over a 48 hour period, and the two 24 hour periods within that time. No sublethal effects of esfenvalerate on M. tasmaniae larvae were detected using the first two criteria. However, using the third criterion esfenvalerate reduced the functional response of third ins tar lacewings in the first 24 hours following spraying. After 48 hours there was no significant difference between the functional response curves of lacewings sprayed with 50 μl a.i./e of water or 0.25 ml a.i./e of water and those treated with distilled water.