A novel mosquiocidal bacterium from soils of Vellore, Tamil Nadu, India

In this study, intensive screening for mosquitocidal bacteria from different agricultural soils of Vellore district of Tamil Nadu was carried out to isolate potential mosquitocidal bacteria. From a total of 315 soil samples, 945 bacterial isolates were cultured, out of which three isolates showed mosquitocidal activity. One most potential mosquitocidal isolate was selected out of these and studied further. The isolate was identified by ilvD primer and phylogenetic tree as Bacillus thuringiensis israelensis. This new isolate exhibited effective toxicity against Aed. aegypti, An. stephensi, and Cx. quinquefasciatus. The LC₅₀ values were 0.757, 0.52 and 0.165 mg/ l respectively. Similarly, the LC₉₀ values were 0.963, 0.794 and 0.355 mg/ l, respectively. These results depict that the new isolate (Bti) VEVP-60 is a good candidate for mosquito control.