Laboratory Evaluation and Bioavailability of Termiticides in Tropical Soils to Subterranean Termites at Different Temperature

Soil termiticide treatment is a fundamental method to control termite population and infestation by creating a continuous barrier surrounding the structures. However, termiticides may dissipate, depending on a half-life, a degradation rate, a leaching activity and a storage method. In this study, the degradation rate and half-life of three commercially available termiticides, with active ingredient of bifenthrin, fipronil and imidacloprid were determined under the field and laboratory conditions. The objective of this study was to determine the bioavailability of termiticides towards subterranean termites (Coptotermes gestroi) termiticides containing active ingredients of fipronil, bifenthrin and imidacloprid under the laboratory conditions at two different temperature 30oC and 40oC using two types of soils i.e. sandy loam and loamy sand no-choice bioassay was done to determine the mortality rate for each termiticide tested. Types of termiticides showed a significant difference toward termite mortality (F= 82.744; df= 2; P= 0.00). Bifenthrin revealed a higher termite mortality compared to fipronil and imidacloprid. Thus, the bifenthrin LT50 and LT95 values were lower compared to fipronil and imidacloprid. Termiticide concentration did affect the termite mortality (F= 9.407; df= 2; P= 0.00) where the higher the concentration, the higher the termite mortality. The laboratory study on termiticide degradation indicated that bifenthrin was more persistent in the soils compared to fipronil and imidacloprid.