| Abstract: | A number of straight-chain and cyclic amidines at sub-lethal concentrations elicit a variety of responses from target organisms, usually expressed as a disruption of normal behaviour, leading to reduced feeding of lepidopterous larvae and tick detachment, or reduced fecundity. These effects are particularly evident in Acarina and Lepidoptera, but can also be seen in members of other insect orders. In some previously unpublished experiments, it was demonstrated that some of these compounds act as ‘locomotor stimulants’ to decrease the feeding of lepidopterous larvae. This type of activity probably results from the interaction of these compounds with aminergic in the case of some compounds identified as octopaminergic neurotransmitter/neuromodulator systems in the target organisms. It is not always clear, however, to what extent this type of activity contributes to the control of pests in the field situation. |
