CONTROL OF MOSQUITO LARVAE (DIPTERA, CULICIDAE) USING BTI AND TEFLUBENZURON - LABORATORY EVALUATION AND SEMIFIELD TEST

A granular formulation, Vectobac-G(R) of Bacillus thuringiensis var. i sraelensis (B.t.i.), and teflubenzuron (CME 134) were found highly eff ective in reducing Aedes aegypti (Bora-bora) larval populations at the mg/L and mu g/L level under laboratory conditions. The LC(95) (24-h, 25 +/- 2 degrees C, L:D = 14:10 h) for Vectobac-G and teflubenzuron ag ainst Bora-bora was 1.64 mg/L and 4.06 mu g/L respectively. Bioassays showed that teflubenzuron has a higher degree of residual activity tha n Vectobac-G. The efficacy of integrating LC,, concentrations of Vecto bac-G and teflubenzuron in different ratios against Bora-bora was stud ied in the lab. Results indicated that the Vectobac-G : teflubenzuron combinations of 1:9 and 9:1 have achieved effective mosquito control o f over 95%. Semi-field tests indicated that the 1:9 combination of Vec tobac-G and teflubenzuron was 1.35 and 1.18 times more effective than the higher-dosage LC(95) concentrations of the two corresponding insec ticides.