A new strain of Bacillus thuringiensis serovar chanpaisis was isolated from soil samples in Thailand. It was classified and characterized in terms of the crystal proteins, carbohydrates fermentation patterns, cry gene content, and its toxicological properties against the species of Lepidoptera, Coleoptera, and Deptera. This strain was identified as Bacillus thuringiensis according to morphological and biochemical characteristics. The strain produced bipyramidal crystal proteins consisting of major bands at about 130 kDa, 85kDa, 64kDa, 50kDa, and 20 kDa. A PCR analysis of the cry genes revealed that only cry32 genes could be detected and localized on chromosomal DNA and plasmid DNA of the organism. The bioassay showed that B. thuringiensis serovar chanpaisis had no larvicidal activity against any species of the Lepidoptera or Coleoptera but exhibited mortality level against Aedes aegypti and Culex quinquefasciatus with LC50 values of 1.48×104 spores mL-1 and 1.00×104 spores mL-1 , respectively.
