So, if IGRs don’t kill cockroaches right away, what’s the point? I want them dead and I want them dead fast!
We all enjoy seeing the immediate results of spray and kill, but IGRs are useful because they prevent future populations from occurring, which is important when you have a large cockroach infestation. If you have a resistant population, having insecticides with multiple modes of action and long residuals will give you better control.
Pyriproxyfen, an IGR found in NyGuard®, has a longer residual than typical adulticides, which means it will not only control the current cockroach population but also prevent other cockroach populations from establishing.
Combining baiting with an IGR residual spray can give you the benefit of not only multiple modes of action, but also different exposure methods. Certain IGRs like pyriproxyfen have a risk profile that allows them to be used in places other insecticides can’t, such as commercial kitchens and other food handling areas. IGRs can also be included in IPM programs and work to control not only cockroaches, but a wide range of other pests.
Exposure to IGRs affect adults and nymphs differently. Adults exposed to IGRs lay fewer eggs and those eggs are less viable.
Nymphs exposed to IGRs experience morphology changes, such as becoming very dark (melanistic) and having twisted wing pads. Nymphs either die during the molting process or become infertile adults, causing the population to decrease until it disappears completely. IGRs also cause nymphs to become more susceptible to non-IGR insecticides, giving you superior, long-lasting cockroach control.
So, the question is, why wouldn’t you include IGRs in your cockroach control program?