Tunneling responses of the asian subterranean termite, Coptotermes gestroi in termiticide-treated sand (Isoptera: Rhinotermitidae)

Abstract

Six termiticide formulations (bifenthrin 24% EC, chlorfenapyr 24% SC, chlorantraniliprole 18.5% SC, fipronil 2.5% EC, imidacloprid 20% SC and indoxacarb 14.5% SC) were evaluated against the Asian subterranean termite Coptotermesgestroi (Wasmann) in the laboratory using glass tube and petri-dish methods. Four concentrations (1, 10, 50 and 100 ppm w/w) were evaluated in the glass tube method, while only the manufacturer's recommended concentration for each termiticide was tested in the petri dish method. Results showed that with the exception of bifenthrin, all termiticides demonstrated non-repellent properties. All termiticide formulations (at concentrations > 10 ppm) were able to stop termite soil penetration, either by killing or repelling them. Termite mortalities caused by the evaluated termiticides were concentration-dependent. Termiticides at 1 ppm were unable to prevent termite tunneling activity, regardless of repellent or non-repellent properties, while termiticides at higher concentrations (eg. 100 ppm) negated or minimized tunneling activity. We suggest that termiticide properties (repellent or non-repellent) may be dependent on the concentrations of the termiticides used.