ABSTRACT
Bacillus thuringiensis is an entomopathogenic bacterium that, during sporulation, produces crystal proteins coded by cry genes, which can act on crop pests such as Spodoptera frugiperda, abolishing its destructive effect. In this study, 20 strains of B. thuringiensis, isolated from different regions of rice production of Rio Grande do Sul, Brazil was characterized. The strains of B. thuringiensis showed characteristic parameters for the species on biochemical, physiological and cytomorphologic specific taxonomic studies of bacteria. The strain MTOX 3420-11 showed mortality exceeding 88% to S. frugiperda and is promising for use in insect biological control. The combination of classical and molecular methods helps to group the isolates and gives more details than a single method for the classification and characterization of native strains with activity against pests.
