Adulticidal activities for contact of Aloysia citriodora (Verbenaceae) against Pediculus humanus capitis (Anoplura, Pediculidae)

GUTIÉRREZ, M.M.; STEFANAZZI, N.; WERDIN GONZÁLEZ, J.O.; FERRERO, A.A.

Congreso; Segunda Reunión Conjunta de Sociedades de Biología de la República Argentina; 2011

The objective of this study was to determine the contact toxicity of essential oil (EO) isolated by hydrodistillation from A. citriodora against human head lice. A Filter-paper contact toxicity bioassay was used and performed in the dark at 31 ± 1ºC and 65 ± 5% RH.Batches of 10 adults were exposed to four concentrations (0.042, 0.126, 0.294 and 0.630 mg/cm2), each of which was dissolved in hexane. Lice were observed for evidence of knockdown every 5 minutes for 1 hour. The criterion for knockdown was when an insect remain on its back with no leg movements. The KT50 was calculated using the program MicroProbit 3.0. Data analysis showed that the KT50 value decreased with increasing concentrations of EO. At the highest concentration, the KT50 (11.37 minutes) was significantly lower than the others KT50 values (P< 0.05). These results indicate that EO from A. citriodora is effective and could be usedas potential P. humanus capitis control agent.