Characterization and Toxicity of Bacillus Thuringiensis Strain Kfr-24, And Commercial Formulations against Spodoptera Littolaris

Abstract

Under these studies Bacillus thuringiensis wettable powder comparable to standard strain, there are only one isolate which confirmed by molecular characterization. Scanning electron microscopy observed that the presence of cuboidal crystals in Bacillus thuringiensis Alex-13, and observed bipyramidal crystals in case of Bacillus thuringiensis HD-1, as standard strain. Polymerase chain reactions (PCR) revealed the presence of Cry1-like sequences in addition to standard strain, which confirmed by gel electrophoresis. Also, during these studies.Bioassay recorded that the highest mortality rate by determination of LC50 for 5 days against Spodoptera littolaris third instars larvae were 69, 86, and 100(%) in case of Bt Alex-13, Bt-HD-1 standard strain and Bt commercial wettable powder, respectively.