Repellency of Formosan Subterranean Termites (Isoptera: Rhinotermitidae) to Dead Termites and Attraction to 2-Phenoxyethanol With and Without Nonrepellent Insecticides

The response of the Formosan subterranean termite to both dead termites and 2-phenoxyethanol with and without nonrepellent insecticide residues was examined using three commercially available pesticide formulations (acetamiprid, fipronil, and imidacloprid). Results indicated that significantly more search tunnels were constructed in the 2-phenoxyethanol-treated sand with three different insecticides compared with the control sand on the first day. The total tunnel network length remained higher on the 2-phenoxyethanol and insecticide-treated sides through the duration of the experiment. Formosan subterranean termites exposed to imidacloprid or fipronil had greater rates of mortality than those exposed to acetamiprid in the study. The increased search activity caused by 2-phenoxyethanol to nearby sites treated with insecticides can reduce the time for termites to contact a toxicant and potentially increases the transfer of the toxicant among termites. Dead termites prevented forager passage regardless of whether the dead individuals were treated with a toxicant or not, therefore decreasing the total tunnel network. Compared with the control, significantly greater rates of mortality occurred in treatments with dead termite barriers. Dead termite barriers that had been treated with any of the three insecticides generally caused greater rates of mortality than those without an insecticide treatment. Dead termites lead to the avoidance of the area by Formosan subterranean termites. One way to overcome this repellency in the field may be to add an attractant like 2-phenoxyethanol.