Published online by Cambridge University Press: 10 July 2009
The development of palatable baits for the suppresion of pest termites relies on combining phagostimulants with slow-acting toxicants that termite foragers carry back to the colony and distribute to nest-mates. In the present study the palatability and toxic effects of three compounds, ampicillin, tetracycline and urea to the subterranean termites Reticulitermes flavipes (Kollar) and R. virginicus (Banks) were investigated. 1.0% solutions (w/v) of ampicillin and tetracycline applied to filter paper were unpalatable to termites in choice tests, and these concentrations depressed termite feeding, survivorship, individual biomass, and numbers of gut protozoa in no-choice tests. In contrast, urea solutions of 0.1%, 1.0% and 5.0% (w/v) were palatable to termites in choice tests, but 5.0% urea solutions depressed termite survivorship and protozoan numbers in no-choice tests. Addition of urea to tetra- cycline solutions resulted in increased palatability and decreased termite survivorship over tetracycline administered alone. The toxic effects in combination with its palatability to Reticulitermes spp. indicate that urea may be a promising candidate for termite control programmes.