(a) clonal propagation of crop plants
(b) developing genetically modified crop plants
(c) production of plant growth substances
(d) production of biofertilizers
3. Ans: b
Explanation:
Bollgard® cotton is the trademark given to a number of varieties of cotton bio-engineered to produce an insecticidal protein Cry1Ac from Bacillus thuringiensis (Bt). When produced by the modified cotton plants, this protein controls certain lepidopterous cotton insect pests.
This product has reduced cotton production costs and insecticide use by providing an effective alternative to chemical insecticides for the control of tobacco budworm, Heliothisvirescens; cotton bollworm, Helicoverpa zea; and pink bollworm, Pectinophora gossypiella
Bollgard‚ cotton, bio-engineered to resist lepidopterous insect pests, has had a dramatic effect on cotton production.
The product concept
Bacillus thuringiensis (Bt), a microorganism found in soil,was known to produce a potent, specific and safe protein insecticide Cry1Ac ). This protein was well characterized, considered safe, and specific to the lepidopterous class of insects.
By introducing the genetic information encoding the insecticidal protein of Bt into plants, these plants would produce their own insecticide. This simple concept promised to reduce insecticide applications, improve insect control, and provide opportunities for aggressive integrated pest management systems while maintaining the inherent safety of this insecticidal protein.
Bollgard(®) cotton, expresses Cry1Ac insecticidal protein.
Bollgard® II cotton was developed by inserting the cry2Ab gene into DP50B Bollgard cotton containing the cry1Ac gene.
Tobacco budworm, cotton bollworm and pink bollworm are more susceptible to the Cry1Ac protein than to Cry2Ab, whereas fall armyworm, beet armyworm, cabbage looper and soybean looper are more susceptible to Cry2Ab than to Cry1Ac.
Bollgard I and II are approved in India.
In India Bt cotton is the only genetically modified (GM) crop that was approved for commercial cultivation in 2002.
Hence, option b is correct.
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