Horizontal transfer of boron by the Formosan subterranean termite (Coptotermes formosanus Shiraki) after feedingon treated wood

Abstract

The goal of the present study was to determine whether Coptotermes formosanus Shiraki workers exposed to boron-treated wood were capable of transferring quantifiable amounts of boron to non-exposed nestmates. This effect is called horizontal transfer. Borates are not repellent to termites, nor do they cause rapid mortality, making them excellent candidates for the study of horizontal transfer. In the present study, C. formosanus workers were collected from field colonies maintained in Honolulu, Hawaii and dyed with Sudan Red 7B over a 7-day period. These termites then underwent a 3-day exposure period to one of two types of composite board, either an experimental formulation of zinc borate and anhydrous boric acid or an untreated composite board. Treated termites were placed with an equal number of untreated termites for either 5 or 10 days; sham-dyed donors and recipients were used to control for possible effects of the dye. Horizontal transmission of boron and toxic effects were assessed based on termite wet weight, percent survival, and boron content. Horizontal transfer of boron was noted at both 5 and 10 days over those levels reported in untreated, field-caught termites from the same colony (ca. 7 mg boron g -1 termites). After 5 days, boron content was elevated in both dyed donor and recipient termites (ca. 92 and 38 mg boron g -1 dyed termites, respectively), as well as in undyed donors and recipients (ca. 84 and 30 mg boron g -1 undyed termites). The same pattern was observed after 10 days in both dyed donor and recipient termites (ca. 61 and 46 mg boron g -1 , respectively) and undyed donor and recipient termites (59 and 24 mg boron g -1 , respectively). Increased boron content of recipient termites after exposure to donor termites (fed on treated wood) demonstrated horizontal transfer of boron.

Lethal Disruption of the Symbiotic Gut Community in Eastern Subterranean Termite Caused by Boric Acid

“…1, Table 1). This finding supports previous observations of dose-dependence in R. flavipes (Su et al 1994), and the termites C. formosanus (Su et al 1994; Gentz et al 2009; Gentz and Grace 2009) and Heterotermes indicola (Wasmann) (Blattodea: Rhinotermitidae) (Farid et al 2015). The highest amount tested in our study was 160 µg of boric acid per 6.8 mg of filter paper, which corresponds to approximately 23,529 ppm (calculated as 160 µg/6800 µg to convert to ppm).…”

Isolation of an Orally Active Insecticidal Toxin from the Venom of an Australian Tarantula

“…Based on the results of the choice test, it appears that OAIP-1 is not repellent. Experiments using lipophilic tracking dyes could be used to determine whether the insecticide could be horizontally transferred, an important feature for commercially-viable termiticides [53].…”

Toxicity, repellency, and horizontal transfer of foam insecticides for remedial control of an invasive drywood termite, Cryptotermes brevis (Blattodea: Kalotermitidae)

“…Untreated termites may also consume a lethal quantity of toxicants when eating, touching, or moving the termite corpses killed by insecticides. Horizontal transfer of fipronil and other insecticides has been extensively investigated against subterranean termites (Rust et al 2006;Green 2008;Gentz et al 2009;Buczkowski et al 2012;Neoh et al 2012;Zhang et al 2022). However, only a few studies have reported horizontal transfer of insecticides in drywood termites (Ferster et al 2001;Rust et al 2008).…”