What do insect growth regulators (IGRs) mimic in insects?

Insect growth regulators (IGRs) are chemical compounds that mimic natural insect hormones, specifically ecdysteroids and juvenile hormones, which play critical roles in the regulation of growth, development, and reproduction in insects. By imitating these hormones, IGRs can disrupt the normal physiological processes of insects, preventing them from maturing properly or reproducing.

This disruption occurs because IGRs can interfere with molting and the development of immature stages, leading to eventual population control of pest species. For instance, the mimicry of juvenile hormones can prevent an insect from completing its metamorphosis, causing it to remain in a larval state or to develop improperly, which ultimately reduces their numbers or renders them incapable of reproduction. This targeting of hormonal pathways makes IGRs an effective tool for managing pest populations in a way that is often less harmful to non-target organisms compared to traditional pesticides.