By Chris Keefer, Technical Services Representative, Syngenta Professional Pest Management German cockroaches pose a threat to public health, causing allergies when large populations go untreated. To provide customers peace of mind from cockroaches, it’s important to understand their biology, ecology and then plan best practices for long-term control. German cockroach life cycle and reproduction Cockroaches undergo incomplete metamorphosis, which includes egg, nymph and adult stages. The average German cockroach life cycle is around 90 days depending on temperature, relative humidity and resources. After mating and feeding, female cockroaches develop an egg case, containing up to 30 individual eggs. They carry the case and then drop it in a hidden location close to resources to ensure access for nymphs. Insect growth regulators for long-term control Insect growth regulators (IGRs) are an effective tool for controlling cockroach populations and can cause: - A decline in production of egg cases
- Fewer viable eggs and egg cases
- Increased nymph mortality
- An increase in aborted egg cases
Since they inhibit the development of immature insect life stages, IGRs are an excellent companion product to use with cockroach baits to suppress populations for a longer time. Use these tips for successful control: - Inspect thoroughly
- Treat all suspected harborage areas (under sinks, behind appliances, pipe chases, etc.)
- Select the appropriate products
- IGRs come in two forms: as a liquid (such as Archer® IGR) and formulated in a bait with an adulticide (such as Advion® Trio cockroach gel bait)
- Use IGRs if the cockroach population is substantial and you don’t know which active ingredients have been used in the past to control cockroaches in the structure
- If using a liquid IGR, it’s important to use it with other active ingredients to maximize control
Understanding cockroach behavior Baits with IGRs use the behavior of German cockroaches against them through the transfer of active ingredients, providing more thorough control of populations. Here’s how it works: - Early-instar nymphs and gravid females don’t forage away from the primary harborage, but instead rely on adult males, non-gravid females and late-instar nymphs to forage and come back to harborage to provide them with resources as they feed on the feces, secretions and remains of dead cockroaches
- Cockroaches that feed on these shared resources will pick up a dose of the IGR
- This indirect transfer not only transfers the active ingredient in the bait, but also transfers the IGRs, which impact reproduction to help manage and control populations
By understanding German cockroach behavior and implementing proper treatment methods, you can help ensure successful, residual treatments and prevent callbacks. For more information, visit SyngentaPMP.com/Cockroach.  © 2024 Syngenta. Important: Always read and follow label instructions. Some products may not be registered for sale or use in all states or counties and/or may have state-specific use requirements. Please check with your local extension service to ensure registration and proper use. Advion®, Archer®, For Life Uninterrupted™ and the Syngenta logo are trademarks of a Syngenta Group Company. Syngenta Customer Center: 1-866-SYNGENT(A) (796-4368). |