The suspected importance of pyrethroid metabolism in resistant H.armigera. made the investigation the biochemical basis of pyrethroid resistance in H. armigera imperative.

The insecticide, endosulfan, is still an effective weapon in the arsenal against Hellothis pest species. It fs used extensively in spring and summer as a cheap alternative to the synthetic pyrethroids.

The Australian Field Crops Resistance Management Strategy has been in place now for 7 seasons.

At the time of the initiation of the H.armigera resistance management strategy, there was a need to demonstrate that any increase in resistance was limited to crops sprayed with pyrethroids.

The frequency of resistance to synthetic pyrethroids in Heliothis armigera has been monitored in the Namoi Valley since the introduction of the insecticide resistance management strategy in 1983.