[Testing the efficiency of Bacillus thuringien israelesis against mosquito larvae in Uzbekistan]

Experiments were conducted in the potential and neighboring malarious areas in the flood plains of the Tupalang River in the Sarias District, Surkhandarya Region, Uzbekistan. They have indicated that the numbers of larvae of pp. Culex and Aedes within the first 24 hours after treatment with BTI drastically reduced with all test doses (0.01-5.0 g/m2) and 92.3-100% larval deaths were recorded. At the same time the efficacy of the drugs retained for more than 7 days (100% death), i.e. throughout the observations. The second experiment have shown that all the test dosage forms of BTI drugs against An. superpictus larvae within 5 days after treatment of water reservoirs displayed virtually a 100% efficacy; on day 7, their efficacy slightly decreased, but remained rather high (75.4-99.7%). On day 14, drugs as granules and emulsions showed a noticeable reduction in their efficacy while the efficacy of powder-like drugs was in the range of 64.2-100%. The power-like drug Vectobac WDG in doses of 0.05-0.2 g/m2 exhibited the longest efficacy (87.6-100%). There was a noticeable increase in the numbers of mosquitoes in the control water reservoirs on days 7 and 14 of experiments.