BIOCONTROL AND LARVICIDAL ACTIVITY OF BACILLUS THURINGINESIS AGAINST THE LARVAE OF MOSQUITO TO COMBAT DENGUE AND MALARIA

Shanu Sharma*

ABSTRACT

With the increasing awareness of the harmful effects of chemicals on man and his environment, the immediate need for sustainable, eco-friendly pest management has been felt very strongly for providing an impetus to research and development of microbial pesticides. A major challenge for achieving successful mosquito control is overcoming insecticide resistance. This study was carried out to assess the larvicidal activity of Bacillus thuringiensis isolated from different soil samples in the regions of Bangalore and Hyderabad using standard methods. Among the different microbial agents developed and tested, bacteria, viruses and fungi are considered promising for the management of insect-pests. The isolate organisms were confirmed as Bacillus thuringiensis based on simple staining, gram staining, coomassie blue staining and their microscopic observation as well by their biochemical characterization. The larvacidal activity of Bacillus thuringiensis isolates was tested against the larval of mosquito by using the standard cup bioassay method using three dilutions of the Bacillus culture. The isolates of Bacillus thuringiensis showed a significant level of variation in their larvacidal activity. From this study, it is concluded that Bacillus thuringiensis is a very potent biolarvicide that can be used to reduce and possibly eradicate the nuisance of disease-causing mosquitoes and aid in the rollback of malaria and other vector borne viral diseases.

Keywords: Dengue, Bacillus thuringiensis, malaria, insecticide, larvicidal, bioassay.