Gene-Edited Rice Varieties
Why in News?
- India has become the first nation globally to develop and approve its first two genome-edited rice varieties, 'DRR Dhan 100 (Kamala)' and 'Pusa DST Rice 1'.
- These climate-resilient crops are engineered using advanced CRISPR-Cas9 technology to enhance grain yields and resource efficiency without introducing any foreign DNA.
Technology Used
- CRISPR-Cas9: Precise molecular scissors make small edits to the plant’s existing DNA.
- SDN-1 and SDN-2: Utilises Site-Directed Nuclease categories that mimic natural plant mutations.
- No Foreign DNA: Unlike GMOs, no genes from other species are added, making them biochemically equivalent to traditionally bred varieties.
Profiles of the New Rice Varieties
- DRR Dhan 100 (Kamala)
- Developer: ICAR-Indian Institute of Rice Research (IIRR), Hyderabad.
- Parent Line: Developed from the highly popular Samba Mahsuri rice variety.
- Targeted Gene: Edits the CKX2 (Gn1a) gene to multiply the number of grains per panicle.
- Key Benefits: Matures 15–20 days earlier, saves irrigation water, and boasts high nitrogen-use efficiency.
- Pusa DST Rice 1
- Developer: ICAR-Indian Agricultural Research Institute (IARI), New Delhi.
- Parent Line: Derived from the southern-suited MTU1010 / MTU 110 fine-grain lines.
- Targeted Gene: Suppresses the Drought and Salt Tolerance (DST) gene to improve survival in harsh soils.
- Key Benefits: Yields jump by 30.4% in coastal salinity, 14.6% in alkaline soils, and 9.6% in inland dry zones.
Agricultural & Environmental Impacts
- Higher Yields: The modifications trigger an overall production surge of up to 19%–30%.
- Water Conservation: Massive reduction in water usage, enough to hypothetically irrigate other crops or meet domestic needs.
- Lower Emissions: Cuts agricultural methane and greenhouse gas emissions by up to 20%.
- Exemption from GMO Rules: The Department of Biotechnology (DBT) exempted SDN-1 and SDN-2 categories from rigid GMO regulations.
- Faster Clearance: Approved directly by Institutional Biosafety Committees (IBSC), dropping multi-tiered, decade-long trials.
Main Debates and Concerns
- Unintended Mutations: Critics warn that CRISPR enzymes can occasionally cause "off-target" cuts in other genomic regions.
- Seed Sovereignty: Activists argue that proprietary gene-editing technology could compromise traditional farmer seed rights.
- Export Risks: Concerns exist that accidental cross-pollination with natural strains might disrupt export markets rigid against bio-engineered foods.
