Context:
The CSIR-National Botanical Research Institute (NBRI) has created the world’s first genetically modified cotton resistant to pink bollworm.
Genetically Modified (GM) Cotton:
- Genetically Modified (GM) cotton, also called Bt cotton, is engineered by introducing a gene from the bacterium Bacillus thuringiensis (Bt).
- The incorporated Bt gene produces proteins toxic to specific pests, providing built-in pest resistance.
Approval of Bt Cotton in India:
- Bt cotton is the only GM crop approved in India for commercial cultivation.
- Approved in 2002 by the Genetic Engineering Appraisal Committee (GEAC) under the Ministry of Environment, Forest, and Climate Change.
Mechanism of Action:
- Bt cotton is genetically modified to produce a toxin from the bacterium Bacillus thuringiensis, lethal to bollworm pests but safe for humans and beneficial insects.
- Gene Insertion: Scientists insert a gene from Bacillus thuringiensis into the DNA of cotton plants, enabling them to produce the Cry protein.
- Toxin Production: When bollworm larvae feed on the cotton plant, they ingest the Cry protein, which becomes toxic in their digestive system, disrupting the gut and causing their death.
- Pest Control:
- The Cry protein specifically targets bollworms, often resistant to chemical pesticides.
- This reduces the dependency on chemical sprays and lowers pesticide usage.
Development of Pink Bollworm-Resistant GM Cotton:
- Background
- GM cotton varieties like Bollgard 1 and Bollgard 2 have been effective against certain bollworm species like American bollworm and spotted bollworm.
- However, these varieties have been ineffective against Pink Bollworm (PBW) due to its resistance to the Cry 1Ac protein.
- Issue Addressed
- The resistance of PBW to Cry 1Ac protein presented a major challenge in pest control.
- Solution
- The CSIR-NBRI developed a novel insecticidal gene, which offers superior resistance against PBW compared to Bollgard 2 cotton.
- This new variety also provides protection against other pests, such as the cotton leafworm and fall armyworm.
Pink Bollworm (PBW):
- Major Cotton Pest:
- Pink Bollworm (PBW), also known as gulabi sundhi, undergoes multiple life stages: egg, larva, pupa, and adult.
- The larva stage is the most destructive, feeding on cotton bolls, causing damage to seeds and fibers.
- Spread and Severity:
- PBW infestation has affected major cotton-growing states, including Gujarat, Madhya Pradesh, Maharashtra, Karnataka, Andhra Pradesh, and Telangana.
- These regions have reported yield losses of up to 30% due to PBW infestations.
Source: Times of India
Previous Year Question
Bollgard I and Bollgard II technologies are mentioned in the context of
[UPSC CSE – 2021 Prelims]
(a) clonal propagation of crop plants
(b) developing genetically modified crop plants
(c) production of plant growth substances
(d) production of biofertilizers
Answer: (b)
Explanation:
Bollgard I Bt cotton (single-gene technology) is India’s first biotech crop technology approved for commercialization in India in 2002, followed by Bollgard II – double-gene technology in mid-2006, by the Genetic Engineering Approval Committee (GEAC), the Indian regulatory body for biotech crops.
