Impact Of Sprays On Baits In Controlling German Cockroaches, Blattella Germanica

Combinations of bait and spray were tested against susceptible and field-collected German cockroaches, Blattella germanica. In exposure tests, residual deposits of all sprays were lethal to a susceptible strain, but pyrethrin and certain pyrethroid sprays were repellent in choice boxes. Indoxacarb bait provided nearly 100% kill of all strains tested, whereas there was a slight decline in activity with clothianidin bait. Indoxacarb bait was effective when applied on treated surfaces or after being sprayed and negated repellency and resistance. The activity of clothianidin bait declined when combined with repellent pyrethrin and certain pyrethroid sprays. In summary, for the best control, apply baits to untreated areas and avoid spraying them.