Mortality Patterns in <I>Coptotermes gestroi</I> (Blattodea: Rhinotermitidae) Following Horizontal Transfer of Nonrepellent and Repellent Insecticides: Effects of Donor:Recipient Ratio and Exposure Time

Abstract

The donor: recipient ratio and the time of donor exposure to termiticide required for maximal toxicant transfer among termites are crucial information for the development of termite management plans. Most of the available information on termiticide toxicity came from temperate zonal termite species, whereas little is known about tropical Asian species. In this study, mortality patterns of recipient termites, Coptotermes gestroi (Wasmann) subjected to seven formulated insecticide exposures under different donor exposure times and donor: recipient ratios were examined. For fipronil, lethal transfer was not affected by donor exposure time but was affected by the mixing ratio. The moderate-to-less toxic termiticides (imidacloprid, indoxacarb, bifenthrin, chlorfenapyr, and chlorantraniliprole) required long exposure time and a high mixing ratio to ensure maximal uptake by recipient workers compared with fipronil. For chlorantraniliprole and chlorfenapyr, donors must constitute > 30% of the donor-recipient mixture to achieve 100% mortality of the recipient workers. Among the termiticides tested, cyantraniliprole was the most fast-killing insecticide against C. gestroi. The potential of lethal transfer among recipient termites does not necessarily require both high donor exposure time and a high mixing ratio, but the toxicity of a given termiticide against termites must be factored in to achieve colony elimination.

Potential toxicity assessment of novel selected pesticides against sand termite, Psammotermes hypostoma Desneux workers (Isoptera: Rhinotermitidae) under field conditions in Egypt

“…Yet, chlorpyrifos is not preferred for termite control because neonicotinoid pesticides and their mammalian toxicities are generally low and show low acute toxicities to birds and fish compared to other common pesticide groups. Chlorpyrifos, though, displayed significant toxicities to bees (Parman and Vargo 2010;Neoh et al 2014;Rondeau et al 2014).…”

Field Distance Effects of Fipronil and Chlorfenapyr as Soil Termiticides Against the Desert Subterranean Termite, Heterotermes aureus (Blattodea: Rhinotermitidae)

“…Studies considering the transfer of chlorfenapyr under laboratory conditions have had mixed results with some evidence suggesting that transfer might be a significant source of mortality in the field. Transfer of chlorfenapyr between nestmate termites has been observed in several species (Rust & Saran, 2006;Shelton et al, 2006;Neoh et al, 2014). In Heterotermes indicola (Wasmann), a species in the same genus as H. aureus, chlorfenapyr transfer was only evident at very low concentration (Misbah-Ul-Haq et al, 2016).…”

“…Formulations containing fipronil are sold under the trade names Termidor (BASF, Florham Park, NJ, USA), Ultrathor (Ensystex, Auburn, NSW, Australia), and Taurus (Control Solutions Inc., Pasadena, TX, USA). Laboratory research has shown that horizontal transfer of fipronil occurs in a variety of termite species (Saran & Rust, 2007;Spomer et al, 2008;Neoh et al, 2014). Furthermore, a few field studies have reported distance effects of fipronil soil application on termite presence near structures in the eastern subterranean termite, Reticulitermes flavipes (Kollar) (Potter & Hillery, 2002;Vargo & Parman, 2012).…”

Inter-species horizontal toxicity: Experimental control of Argentine ants and their citrophilus mealybug mutualists in a viticultural system

“…effectively in vineyards and citrus groves including the organophosphates chlorpyrifos and terbufos and the pyrethroid α-cypermethrin (Addison, 2002;James, Stevens, & O'Malley, 1998;Klotz et al, 2003). Non-repellent contact insecticides allow the insect species to acquire the toxicant without detecting it and then transfer it horizontally to other fit nestmates (Neoh, Yeoh, & Lee, 2014;Rust, Reierson, & Klotz, 2003;Shelton & Grace, 2003).…”

“…Bifenthrin is used by urban pest management personnel as a barrier treatment around homes, hospitals, nursing facilities and in electrical casing, targeting termites and ants including the invasive ant species L. humile and Solenopsis invicta (Choe & Rust, 2008;Klotz, Rust, Costa, & Reierson, 2002;Neoh et al, 2014;Pranschke, Hooper-Bùi, & Moser, 2003). Bifenthrin (Fig.…”