What is Bt Corn
Bt corn is a genetically modified organism (GMO) that is created by inserting a bacterial gene called Cry1Ab from Bacillus thuringenesis into the DNA of the desired plant. This enables the corn to produce a protein called Bt-Delta Endotoxin. It is very effective for restricting the growth of Lepidoptera larva, caterpillar during the larva stage. Bt-delta endotoxin is a deadly toxin for insects but harmless for humans, mammals, birds, fish and environment.
What is GMO
A GMO is basically a plant or an animal that has been modified genetically through the addition of a genetic material from other organisms using molecular techniques. To make a GMO plant, first comes a donor organism that may be a bacterium or fungus or any plnat from which the gene of interest can be obtained. The gene is first identified and then separated from donor’s genetic material. Then the gene of interest is inserted in the DNA of the target organism. The whole process of transforming a plant into a GMO is a very complex one.
How corn is genetically modified
- At first, the desired Cry1Ab gene with required characteristics is extracted from bacteria (Bacillus thuringenesis)
- The gene is then integrated in the DNA of another bacteria
- The bacteria with the integrated gene is then multiplied in a bacterial culture medium
- After that the gene should be inserted into the plant cell’s chromosome. To do this, the copied of the gene are first fixed onto tungsten microparticles.
- The microparticles are blasted into plant cells under gas pressure and the gene is integrated into the cell chromosomes
- The plant, growing with this gene, posses the desired trait such as resistance to insects and herbicides
How it works
Bt-Delta Endotoxin is deadly for insects. When an insect inject this Bt protein, within minutes it starts showing affect. The insect stops feeding and the protein binds to the gut wall of the insect. The gut wall breaks down within a few hours and normal gut bacteria invade the body cavity. The bacteria starts multiplying in the blood as a result the insect dies of septicaemia.