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Used as alternative to DDT and organophosphates since the 1920s
Bt toxin is used as specific insecticides under trade names such as Dipel and Thuricide

1. Botanical pesticides

2. About 90 species of bacteria pathogenic to insect pests. Bacillus thuringiensis – first discovered in 1902- japanese bacteriologists, Ishiwata from infected silk worms stands out prominent

3. Bacillus thuringiensis Bacillus popillae Bacillus sphaericus Coccobacillus acridorum Serratia marcescens

4. B. thuringiensis (‘ Bt ’) is a spore forming gram positive crystalliferous soil bacterium. Produces a toxin or crystal protein ( Bt toxin or Cry) that kills certain insects Commercially produced worldwide using fermentation technology.

5. The commercial Bt products are produced as dust, wettable powder and emulsifiable concentrates. The toxin genes have also been genetically engineered into several crop plants.

6. The Bt toxin or Cry is produced when the bacteria sporulates and is present in the parasporal crystal Several different strains and subspecies of B. thuringiensis exist and produce different toxins that kill specific insects

7. Used as alternative to DDT and organophosphates since the 1920s Bt toxin is used as specific insecticides under trade names such as Dipel and Thuricide