Monday, December 10, 2007 - 9:17 AM

Palatability and efficacy of emamectin benzoate gel bait on four pest cockroach species

Barbara E Bayer,, University of Florida, Department of Entomology and Nematology, Bldg. 970, Natural Area Dr, Gainesville, FL and Phil Koehler,, University of Florida, Entomology & Nematologoy, Building 970 Natural Area Drive, Gainesville, FL.

Cockroaches are important pests in and around urban structures, and gel baits are a primary method of control. Choice experiments using dog food and a gel bait formulated with 0.1% emamectin benzoate were conducted to determine palatability of gel bait and efficacy of emamectin benzoate to control four species of pest cockroaches. Either mid-instar nymphs or mixed populations of cockroaches were placed into arenas with harborage and water, and then starved for 24 h. Cockroaches were then provided a choice of pre-weighed dog food or emamectin benzoate gel bait. Twenty-four hours after introduction, the dog food and emamectin benzoate gel bait were re-weighed. Percentage of total consumption that was gel bait was calculated. Mortality was recorded at 14 d. American cockroaches preferred gel bait, almost exclusively, with 99.7% of total consumption being gel bait. Oriental cockroaches also had a strong preference for gel bait with 92.4% of total consumption. For bait averse German cockroaches, 85.0% of total consumption was gel bait. Brownbanded cockroaches had no preference for gel bait over dog food and 58.4% of total consumption was gel bait. Ninety to ninety-two percent of all American and Oriental cockroaches, as well as 97% to 98% of all bait averse German and Brownbanded cockroaches, were dead, 14 d after exposure to gel bait. Emamectin benzoate gel bait at 0.1% is an excellent candidate for controlling all the pest cockroaches tested.

Species 1: Blattodea Blattellidae Blattella germanica (German cockroach)
Species 2: Blattodea Blattidae Periplaneta americana (American cockroach)
Species 3: Blattodea Blattidae Blatta orientalis (Oriental cockroach)