CHARATERIZATION OF BACILLUS SPHAERICUS LP1-G AND ITS TOXICITY AGAINST SUSCEPTIBLE AND RESISTANT MOSQUITO LARVAE

Bacillus sphaericus LP1-G, belonging to serotype H3, can grow and develop well in MBS media and synthesize 41.9 and 51.2kD proteins, which resemble in a parasporal form during sporulation. SDS-PAGE analysis showed that this strain can also synthesized another 49kD peptide during sporulation. The sporangium and spore/ crystal cultures of LP1-G had medium toxicity against 3-4 instar Culex quinquefasciatus, in comparison, the vegetative culture had no toxicity against the target larvae. It has also been found that the final whole culture had same activity to both susceptible and resistant C. quinquefasciatus and the LC_50 values at 48h were 0.113 and 0.1117mg/mL respectively. It is suggested that the presence of P49 protein in LP1-G could be responsible for its toxicity against both susceptible the resistant mosquito larvae.