Bacillus thuringiensis spore forming, Gram positive aerobic bacteria whose spores consist of the crystal protein which are found to have the insecticidal activity to the specific insect orders. Bacillus thuringiensis are considered to be cosmopolitan in nature and a great difference occurs between the two strains from different habitat. The present study was conducted on the collection of samples and solation of the B.t. from these samples. These isolates were identified on the basis of microscopic techniques and staining techniques. Culturing of these isolates was made on the specific media such as T3. Culturing of these bacteria was done to get enough amount of the B.t. spore cell. Rearing of the Tribolium castaneum a flour beetle was done by understanding the physiology of the beetles. Then biotoxic effect of these bacteria was determined by the process of Biotoxicity assay of the Bacillus thuringiensis spores against Triboium castaneum in glass vials in triplicates. The seven day repeated observation of these isolates was presented in the tabular form and LC50 is calculated by the Probit analysis programme.

The study conducted on the toxic effect of the Bacillus thuringiensis spores against the Tribolium castaneum can be of great importance in eliminating the stored pest grains. There are a lot of future perspectives of this study which are given below: Proper processes for the collection and handling of the samples should be under consideration in order to avoid the incorrect and contaminated samples from different sources. According to the nutritional requirements of the Bacillus thuringiensis a specific solid media called as T3 media is used for the culturing of these bacteria and incubation period of these is 72 hours for spore formation. To understand the physiology of the Tribolium castaneum is quite helpful in understanding the rearing processes of these beetles. Biotoxiciy assay provides a reliable method for determining the susceptibility of the Tribolium castaneum against Bacillus thuringiensis that provide an easy method to determine the mortality ratio. The spores of the Bacillus thuringiensis can be of great importance in the agriculture in reducing the considerable population of the stored grain pest such as Tribolium castaneum and also some other pests.