Synergized pyrethrins insecticide as a spot treatment option for West Indian drywood termites
IRG/WP 23-11004
B Hassan, C J Fitzgerald
Pyrethrin is a natural biopesticide with relatively low mammalian toxicity. Two identical products in Australia contain pyrethrin in liquid CO2-propelled aerosol, Pestigas from BOC international and SupaPy Supagas. In the current study, the toxicity of SupaPy was tested against West Indian drywood termite Cryptotermes brevis as an option for spot treatment of this pest. Termites were exposed to wood surfaces treated with SupaPy in short and continuous exposure tests. Vapor toxicity was determined in lab tests, and penetration of SupaPy through termite fecal pellets was assessed using silicon airline tubing. Results showed that exposure of termites to SupaPy through wood-treated surfaces resulted in rapid mortality. Less than 20% of termites survived even when termites were exposed to a SupaPy-treated wood surface for a minute. All termites died within 1-5 hours in continuous exposure tests, depending on the age of the treated surface. SupaPy was not volatile enough to produce complete mortality of termites even after 196 hours when there was no contact of termites with a treated surface. The number of termites that survived following the application of SupaPy through silicon tubing with fecal pellets was also negligible, demonstrating the ability of SupaPy to penetrate through loose pellets and ultimately resulting in a distribution that is nearly ideal in the termite galleries.