Genomic Innovation in Agriculture: The Rise of CRISPR-Cas9 in Plant Improvement

Abstract

CRISPR-Cas9 technology has transformed plant biotechnology by allowing precise genome editing, leading to remarkable enhancements in crop characteristics like yield, disease resistance, stress tolerance, and nutritional value. This article examines the molecular workings of CRISPR-Cas9, highlights its wide-ranging applications in various plant species, reviews significant case studies, and addresses current challenges and prospects for the future. Real-world examples are backed by recent peer-reviewed research.

Introduction

Global food demand is rising due to population growth and climate change. Traditional breeding methods are slow and imprecise, prompting the use of CRISPR-Cas9, a powerful genome-editing tool adapted from a bacterial immune system. It enables precise genetic modifications by creating DNA double-strand breaks (DSBs), repaired by the cell via non-homologous end joining (NHEJ) or homology-directed repair (HDR).

Key Applications in Crops:

1. Enhanced Yield:

   • Editing yield-related genes like GN1a in rice and CKX in wheat boosts grain production and biomass.

2. Improved Nutrition:

   • Modifying sugar transport and metabolism genes in rice and tomatoes enhances sugar and carbohydrate content.

   • Editing carotenoid pathway genes increases provitamin A levels in rice.

3. Disease Resistance:

   • Knocking out MLO genes in wheat and altering SWEET gene promoters in rice confers resistance to fungal and bacterial infections.

4. Stress Tolerance:

   • Targeting genes like DREB in chickpea and HyPRP1 in tomato improves drought, heat, and salt tolerance.

Case Studies:

• Soybean: GmEOD1 editing increased seed size.

• Rice: GN1a edits raised grain number.

• Tomato: Sugar regulation improved sweetness.

• Wheat: MLO gene knockout enabled fungal resistance.

• Chickpea: Stress-related gene edits enhanced drought tolerance.

Challenges & Future Prospects:

1. Off-target Effects:

   • Precision improvements include high-fidelity Cas9 variants and new tools like base and prime editors.

2. Regulation & Public Perception:

   • Varying regulations globally; public concerns require better communication on safety and benefits.

3. Technical Limitations:

   • Difficulties in gene delivery and plant regeneration remain; novel delivery methods like nanoparticles offer promise.

4. Future Directions:

   • Innovations include multiplex editing, epigenome editing, and combining CRISPR with synthetic biology and traditional breeding for sustainable crop improvement.

Conclusion

Global food demand is rapidly increasing due to population growth, shifting dietary habits, and environmental stresses caused by climate change. Traditional plant breeding techniques are often slow and imprecise, typically requiring several generations to stabilize desired traits (Tester &Langridge, 2010). CRISPR-Cas9, originally an adaptive immune system in bacteria, has been adapted for precise genome editing, offering unmatched accuracy and efficiency (Jinek et al., 2012). This technology creates targeted DNA double-strand breaks (DSBs), which are then repaired by the cell’s natural mechanisms, enabling precise knockout, insertion, or modification of genes linked to important agricultural traits (Doudna&Charpentier, 2014; Bortesi& Fischer, 2015).

References

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Copyright

Copyright © 2025 Tahir Metkari, Sonakshi Bankar. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.