Identification and Characterization of Bacillus thuringiensis Strain BRC-ZLL13 with High Toxic Activity Against Mosquitoes

Bacillus thuringiensis strain BRC-ZLL13 was isolated from leaves of Magnolia aenudate . It was characterized based on its insecticidal activity against Aedes aegypti , Aedes albopictus , and Culex quinquefasciatus larvae, flagellar antigen serology, biochemical reactions, antibiotic sensitivity, plasmid profile and crystal protein profile as well as PCR analysis using novel general and specific primers for cry and cyt genes analysis. It showed more than twofold higher mosquitocidal activity against A. aegypti , A. albopictus and C. quinquefasciatus larvae than B. thuringiensis subsp. israelensis (IPS82) and displayed high similarities with the IPS82 with regard to protein and the presence of mosquitocidal genes, but had different plasmid profiles and higher growth rate. These results suggested that the loss of plasmid might be contribute to high growth rate of this strain, and indicated a potential for developing this strain for application in the fields of public hygiene and biological control.