India bets on gene-edited rice varieties as yield growth slows
India's rice sector is seeing a slowdown in yield growth, prompting renewed emphasis on advanced hybrid and genome-edited varieties to boost productivity
The push builds on India's release of its first genome-edited rice varieties, developed using CRISPR-Cas9 technology
These varieties target improved yield, drought and salinity tolerance, and reduced input requirements (water, nitrogen) compared to conventional varieties
The development is positioned as part of a broader strategy to sustain productivity gains as traditional yield-improvement methods show diminishing returns
Genome Editing vs. Genetic Modification — SDN Classification
Genome-edited crops are regulatory distinct from genetically modified organisms (GMOs) because they use techniques like CRISPR-Cas9 to make precise edits to a plant's own DNA without introducing foreign genetic material — a key distinction that shaped India's 2022 regulatory guidelines exempting certain categories of gene-edited crops from GMO-level biosafety scrutiny.
Key Details
- Site-Directed Nuclease (SDN) technology is classified into three types: SDN1 (small edits/deletions without foreign DNA template), SDN2 (small edits using a DNA template), and SDN3 (insertion of foreign DNA, treated like conventional GM)
- India's DRR Dhan 100 (Kamala) and Pusa DST Rice 1 were developed using SDN1 editing, meaning no foreign DNA was introduced — this classification exempted them from the stricter regulatory pathway applicable to GM crops under the Environment Protection Act, 1986 rules
- The Ministry of Environment, Forest and Climate Change (MoEFCC) issued guidelines in 2022 exempting SDN1 and SDN2 genome-edited plants from Rules 7-11 of the Rules for Manufacture, Use, Import, Export and Storage of Hazardous Microorganisms (1989), which otherwise govern GM crop approval
The regulatory distinction between SDN1/SDN2 genome editing and conventional GM technology is what allowed India to release these rice varieties for cultivation relatively quickly, without the prolonged biosafety trials associated with Bt cotton or GM mustard.
DRR Dhan 100 (Kamala) and Pusa DST Rice 1 — India's First Genome-Edited Crops
India became the first country to develop and release genome-edited rice varieties for cultivation, announced in May 2025. The two varieties were developed by ICAR institutes using CRISPR-Cas9 to edit specific genes controlling yield and stress tolerance in existing popular rice varieties, rather than introducing entirely new genetic traits.
Key Details
- DRR Dhan 100 (Kamala): developed by ICAR-Indian Institute of Rice Research (ICAR-IIRR), derived from the widely cultivated Samba Mahsuri variety; edits the Cytokinin Oxidase 2 (CKX2)/Gn1a gene to increase grain number, delivering an approximately 19% yield increase alongside earlier maturity and improved drought/salinity tolerance
- Pusa DST Rice 1: developed by ICAR-Indian Agricultural Research Institute (ICAR-IARI), derived from Cotton Dora Sannalu, engineered for drought and salt tolerance with reported yield gains of roughly 9.7% to 30.4% in saline/alkaline soils
- Both varieties were developed under India's National Agricultural Science Fund-supported genome editing research programme at ICAR
These two ICAR varieties form the technological foundation for the current push described in the report — as conventional yield growth from hybridisation plateaus, genome-edited varieties represent the next productivity lever being scaled up.
Yield Growth Stagnation and India's Agricultural Productivity Challenge
India, despite being the world's largest rice exporter and second-largest producer, has seen slowing growth in per-hectare rice yields in recent years due to a combination of stagnant genetic gains from conventional breeding, climate stress (erratic monsoons, heat, salinity intrusion in coastal areas), and pest/pathogen pressure — a challenge global agricultural research bodies have flagged as a threat to food security.
Key Details
- Genome editing offers a faster breeding cycle than conventional hybridisation because it edits existing high-performing varieties rather than requiring multi-generation crossbreeding to introgress new traits
- Climate stress factors (drought, salinity, elevated temperatures) are cited as key drags on yield growth, directly addressed by the stress-tolerance traits engineered into both new rice varieties
- India's rice productivity gains are also tied to input-efficiency metrics like nitrogen-use efficiency and irrigation water savings, both improved in the Kamala variety
The article frames genome-edited rice as a structural response to yield stagnation — a shift from breeding for yield alone toward breeding for yield-under-stress, aligned with climate adaptation priorities in Indian agriculture.
- India released its first genome-edited rice varieties: May 2025 — DRR Dhan 100 (Kamala) and Pusa DST Rice 1
- Technology used: CRISPR-Cas9, SDN1 category (no foreign DNA introduced)
- Kamala's reported yield increase: ~19%; also ~20% reduction in greenhouse gas emissions and substantial irrigation water savings
- Pusa DST Rice 1's reported yield increase: 9.66% to 30.4% in saline/alkaline soils
- Regulatory basis: 2022 MoEFCC guidelines exempting SDN1/SDN2 genome-edited plants from GM-level biosafety rules under the Environment Protection Act, 1986
- Developing institutions: ICAR-IIRR (Kamala) and ICAR-IARI (Pusa DST Rice 1)