Cultivation of Bt cotton has been much in the news. The prefix Bt stands for
Bt cotton, Bt tobacco, Bt tomato, etc are transgenic plans having Bt-2 gene encoding Bt toxin, (e.g., thurioside). Bt toxin gene has been isolated from a bacterium Bacillus thuringiensis therefore, called Bt. These plants are resistant for more than 140 species of insects including common cabbage worm, caterpillars, bag worms, canker worms, gypsy worm, etc.