Abstract

Bacillus thuringiensis (Bt) is an ubiquitous Gram positive, spore forming bacterium that forms parasporal crystal inclusions. These proteinaceous inclusions are called crystal (Cry) proteins or delta- endotoxins, which are toxic to insects. Hence preparations of Bt are being used as bioinsecticides for the past four decades in commercial agriculture and forest management for the control of certain insect species belonging to the orders of Lepidoptera, Diptera and Coleoptera. Bt is a major source for transfer of genes into plants to impart insect resistance. Since 1996 millions of hectares are grown with insect resistant transgenic plants containing Bt genes, in different parts of the world. Commercial release of transgenic Bt cotton in India is expected soon.

Keywords: Bacillus thuringiensis, Biopesticide, Transgenic plants