Environmentally friendly insecticides

By targeting the chemistry of the insects own hormones, CSIRO is developing a new class of insecticide that is pest-specific and produces no harmful side-effects.

• 20 July 2006 | Updated 14 October 2011

• Overview
• Current activities
• Outcomes

Overview

Controlling insect pests is an extremely important issue for the twenty-first century. Over the past 40 years the total area of land under crops has changed little, however output has trebled. Much of this has been accomplished by the use of chemical pesticides.

By targetting the chemistry of the insects own hormones, CSIRO researchers – in collaboration with Australian Wool Innovation (AWI) Ltd – are developing a new class of insecticide that is pest-specific and produces no harmful environmental side-effects.

An insect’s hard exoskeleton or cuticle cannot expand as it grows, which means that this cuticle must be shed at certain moulting stages during the insect's normal life cycle. This process is controlled by ecdysone, an insect hormone which regulates gene activity during metamorphosis, reproduction and moulting.

Current activities

CSIRO scientists have recently defined the structure of ecdysone receptors for certain insect pests. They are now using that information to design synthetic molecules to interact with these receptors to switch on the genes controlling growth and development at the wrong time, causing the insects to moult prematurely and die.

By targetting the ecdysone receptor of a specific insect, scientists will be able to design insecticides that will bind selectively to that receptor. As the receptor is absent in humans, mammals, birds and fish, toxicity will be focused on the targeted pest species allowing preservation of biodiversity.

Outcomes

While the technology can be applied to all insect pests, the first application of this research is directed to environmentally friendly and safe control of sheep blowfly and body louse.

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