Which group of pesticides disrupts the molting process of the immature stages?

Insect growth regulators (IGR) are particularly designed to interfere with the normal developmental processes of insects, specifically targeting immature stages. They function by mimicking hormones that dictate growth and molting, disrupting the insect's natural cycle of development. This disruption leads to problems such as incomplete molting or failure to develop into mature adults, effectively reducing the population of pests like mosquitoes.

The focus of IGRs on the hormonal control of growth makes them especially effective in managing insect populations, as they target the life stages where traditional insecticides might not be effective. They provide a more environmentally friendly approach to pest control since they are less harmful to non-target species and can help reduce reliance on more toxic insecticides.

In contrast, pyrethroids, organophosphates, and neonicotinoids operate through different modes of action, such as neurotoxicity. While these pesticides can effectively kill mature insects, they do not target the molting process or the immature stages in the same specific manner as IGRs. Consequently, IGRs provide a unique advantage in disrupting the lifecycle of mosquito populations by preventing them from reaching maturity.