Agonists for tyramine (TA) receptor were tested for inhibitory specificity using a modified radiochemical bioassay to monitor de novo pheromone production in Plodia interpunctella. Arylaldehyde semicarbazones (AASs) and 5-aryloxazoles (AONs) had the highest potency in inhibition of pheromone production in vitro and calling behaviour, respectively. There are several receptors that can be activated by octopamine (OA) in the central nervous system that can either activate or inhibit adenylate-cyclase activity. Effect of TA and OA on insect behaviour such as sex-pheromone production and metamorphosis is discussed in detail.