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The toxicity and horizontal transmission of thiamethoxam was evaluated in the workers of the Asian subterranean termite Coptotermes gestroi Wasmann (Isoptera: Rhinotermitidae). Brief exposure to sand treated with thiamethoxam at concentration ranging from 0.25 to 50 µg/ml resulted in a dose-dependent mortality in C. gestroi. Sand treated with 50 µg/ml thiamethoxam resulted in very high mortality within 30-60 min of exposure. Termites exposed to sand treated with 0.25-25 µg/ml exhibited delayed toxicity and nonrepellency in C. gestroi. A horizontal transmission study using 25 µg/ml of thiamethoxam at donor-recipient ratio of at least 2:5 (treated:untreated) indicated that thiamethoxam can be transferred between exposed and unexposed workers, resulting in significant termite mortality in unexposed termites within 1-3 d post exposure., (© The Author 2014. Published by Oxford University Press on behalf of the Entomological Society of America.)

Oil of the physic nut, Jatropha curcas L. (Malpighiales: Euphorbiaceae), was evaluated in the laboratory for its barrier and repellent activity against the Philippine milk termite Coptotermes vastator Light (Isoptera: Rhinotermitidae). The study showed that J. curcas oil had anti-feeding effect, induced reduction in tunneling activity and increased mortality in C. vastator. Behavior of termites exposed to sand treated with J. curcas oil indicated that it is toxic or repellent to C. vastator. Toxicity and repellent thresholds, were higher than those reported for other naturally occurring compounds tested against the Formosan subterranean termite.

Thiamethoxam (ACTARA 25WG) was evaluated for its termiticidal properties against three species of economically important subterranean termites (Isoptera: Termitidae) in the Philippines: Nasutitermes luzonicus Oshima, Macrotermes gilvus Hagen, and Microcerotermes losbanosensis Oshima. Results of the study indicated that exposure to soil or ingestion of paper treated with thiamethoxam at concentration above 0.41 ppm may provide an adequate chemical barrier or induce high mortality against N. luzonicus, M. gilvus and M. losbanosensis after 5-9 days. Feeding bioassays showed that thiamethoxam was not repellent to M. gilvus and M. losbanosensis but had an anti-feeding effect on N. luzonicus.