EFFECTIVENESS AND RESIDUAL ACTIVITY COMPARISON OF GRANULAR FORMULATIONS OF INSECT GROWTH REGULATORS PYRIPROXYFEN AND S-METHOPRENE AGAINST FLORIDA MOSQUITOES IN LABORATORY AND OUTDOOR CONDITIONS

Effectiveness and residual activity tests of granular formulations of 2 insect growth regulators (IGRs), S-methoprene and pyriproxyfen, against laboratory-reared larvae of 5 colonized mosquitoes, Aedes at.- gypti, Aedes albopictus, Aedes taeniorhynchus, Anopheles quadrimaculatus, and Cufex nigripalpus, were con- ducted in the laboratory and outdoors in plastic tubs. Culex quinquefusciatus was exposed to these two IGRs in the laboratory only. Each IGR formulation was applied at 0.02 and 0.05 ppm active ingredient (AI) against 5 of the 6 mosquito species both in the laboratory and the outdoor evaluations, whereas Cx. quinquefa.sciatus was exposed to 0.2 and 0.4 ppm AI of S-methoprene, and 0.1 and 0.2 ppm AI of pyriproxyfen in the laboratory. S- Methoprene at 0.02 and 0.05 ppm AI resulted in variable levels ( 80-100% in most cases) of initial and residual emergence inhibitions of the tested species in the laboratory as well as outdoors. In several species, pyriproxyfen induced complete inhibition of adult emergence for several weeks after treatment, even at the lower rate of 0.02 ppm. The World Health Organization has recently recommended the use of pyriproxyfen for the control of some mosquito species at specified rates in certain habitats.