EFFICACY OF GROUND ULTRA-LOW VOLUME LARVICIDAL TREATMENTS USING TEMEPHOS AND BACILLUS-THURINGIENSIS VAR ISRAELENSIS AGAINST CULEX-PIPIENS LARVAE

Spray drift determinations of truck-mounted ULV applications of temeph os and Bacillus thuringiensis var. israelensis (B.t.i.) in simulated f ield trials were conducted in the Baix Llobregat area near Barcelona, Spain, using larval Culex pipiens as bioindicators. A 50:50 temephos:o il mixture applied at 350 ml/min, while traveling 9 kph, resulted in 1 00% control of larvae 10-50 m from the point of application (with the exception of 82% mortality at 30 m); control decreased rapidly to 50% at 55 m. Mortality due to B.t.i. application ranged from 92 to 100% wi thin 12 m, and generally decreased therafter to about 11% at 30 m.