TLS Online TPP Program

#Id: 6163

#Unit 12. Applied Biology

Insect-resistant transgenic crops were first commercialized in the mid-1990s with the introduction of GM corn (maize), potato and cotton plants expressing genes encoding the entomocidal δ-endotoxin from Bacillus thuringiensis.

TLS Online TPP Program

#Id: 6164

#Unit 12. Applied Biology

The first commercial Bt cotton variety was released in USA by Monsanto (Bollgard), which contains Cry 1Ac gene of Bacillus thuringiensis. (first generation Bt-cotton)

TLS Online TPP Program

#Id: 6165

#Unit 12. Applied Biology

Second generation of improved Bt-cotton with two Bt-genes, now designated Bollgard II.  Bollgard II cotton contains Cry 1 A(c) and Cry II A(b).

TLS Online TPP Program

#Id: 6166

#Unit 12. Applied Biology

B. thuringiensis is a spore forming bacterium, which produces a crystal protein as parasporic inclusion in the vegetative cell containing the spore.

TLS Online TPP Program

#Id: 6167

#Unit 12. Applied Biology

The cry gene of B. thuringiensis produces a protein, which forms crystalline inclusions in the bacterial spores. These crystal proteins are responsible for the insecticidal activities of the bacterial strains.

TLS Online TPP Program

#Id: 6168

#Unit 12. Applied Biology

Cry proteins divided into four main groups or first ranks, viz., Cryl, Cry II, CryIII and CryIV, on the basis of their insecticidal activities.