Division of Medical Entomology and Vector Control, National Institute of Communicable Diseases, Directorate General of Health Services, 22-Shamnath Marg, Delhi-110 054 (India).
Laboratory bioassay tests carried out with chloropyrifos-methyl revealed that 0.01 ppm induced 100.0 per cent larval mortality in Cx quinquefasciatus as also 0.005 ppm in An. stephensi and Ae. aegypti. LC50 and LCm values estimated were An. stephensi (0.0009 & 0.0024), Ae. aegypti (0.0007 & 0.0022) and Cx. quinquefaciatus (0.0012 & 0.0041). The residual effect of the compound at 0.01 ppm inducing 100.0 per cent larval mortality was 9, 7 and 4 weeks for Ae. aegypti, An. stephensi and Cx quinquefasciatus, respectively. However, it could induce only 50.0 per cent mortality in Ae. aegypti, An stephensi and Cr quiquefascaitus up to 15th, 13th and 11th week, respectively.
