Transfer of indoxacarb among workers of Coptotermes formosanus (Isoptera: Rhinotermitidae): effects of dose, donor:recipient ratio and post‐exposure time

Abstract

Horizontal transfer of indoxacarb among workers of the Formosan subterranean termite, Coptotermes formosanus Shiraki, was examined under laboratory conditions. The effects of dose (0, 10, 20, 50, 100 or 200 ng AI per donor), donor:recipient ratio (1:1, 1:4 or 1:9) and post-exposure time (2, 4, 8, 16, 20 and 24 days) on lethal transfer of indoxacarb were investigated using a donor/recipient model in groups of 100 workers. Transfer of lethal doses from donors to recipients was evidenced by significant recipient mortality in 13 out of 15 treatments within 24 days post-exposure. Dosage significantly affected indoxacarb transfer. Higher doses resulted in greater recipient mortality than lower doses. The highest dose tested resulted in 100% death of recipients and donors within 20 days. A dose of 100 ng resulted in recipient mortalities ranging from 68 to 100%, whereas doses < or =50 ng killed <60% of recipients within 24 days. Donor:recipient ratio also had considerable effect on indoxacarb transfer. At 24 days post-exposure, greater recipient mortalities were observed at ratios > or =1:4 at doses > or =20 ng, but only at a ratio 1:1 at dose 10 ng. Recipient mortality increased significantly as post-exposure time increased. The higher the doses applied on donors, the shorter were the times required for the onset of recipient mortality to occur and for recipients to reach maximum mortality. Significantly greater recipient mortalities were not observed at doses 20 and 50 ng until more than 20 days post-exposure, indicating a delayed activity of indoxacarb. Possible transfer mechanisms are discussed.

Toxicity of Seven Termiticides on the Formosan and Eastern Subterranean Termites

“…The mode of action of indoxacarb is to block the sodium channels in insect nervous system like the older classes of insecticides, such as DDT and pyrethroids, but it acts on a different binding site (Wing et al 2000, Nauen andBretschneider 2002). They are the newest compounds under development as termiticides (Hu et al 2005, Spomer et al 2009) (Altriset, granted EPA Section 3 registration in May 2010). Fipronil (Termidor, 98.9%), imidacloprid (Premise, 99.5%), chlorfenapyr (Phantom, 99.2%), and bifenthrin (Talstar, 99.0%) are the active ingredients in some presently registered soil termiticides and were purchased from Chem Service, Inc. (West Chester, PA).…”

Contact Versus Feeding Intoxication by Fipronil in <I>Reticulitermes</I> Termites (Isoptera: Rhinotermitidae): Laboratory Evaluation of Toxicity, Uptake, Clearance, and Transfer Among Individuals

“…When termites ingest Þlter paper treated with 1 ppm Þpronil, mortality is Ͼ80% in 5 d (Remmen and Su 2005b). Hu et al (2005) observed that termites penetrated 20-mm treatments at 1Ð100 ppm and 50-mm treatments at Յ10 ppm. The maximal distance of termite movement away from the treated area is Ϸ2 m Rust 2007, Ripa et al 2007).…”

Combinatorial Potential of bait matrix against subterranean termites under lab and field conditions

“…Key among these mechanisms is trophallaxis, which facilitates the spread of bait toxicants (Hu et al, 2005), and mutual grooming which facilitates the spread of liquid spray insecticides (Soeprono & Rust, 2004). Control of subterranean termite was transfigured when first termite bait product was registered by Dow AgroSciences LLC (formerly known as ~ow~lanco) .…”