Swiftly evolving CRISPR genome editing: a revolution in genetic engineering for developing stress-resilient crops

Abstract: Environmental stresses adversely impact crop production, crop quality and product safety. Climate change is predicted to exacerbate the impacts of stresses on current cropping systems with multilateral impacts on crop productivity and yield, biodiversity, soil fertility, microbial activity and carbon sequestration. Transforming crop production systems and developing stress and climate-resilient crops are paramount to alleviate pervasive food and nutrition security and food safety issues and achieve a world free from hunger and malnutrition. Modern breeding techniques have been the key to transforming crop production systems and developing stress- and climate-resilient crops. As a rapidly evolving technology, the Nobel Prize-winning CRISPR method is a leading choice for genome editing and a possible major contributor to solving environmental and food insecurity issues. Here, we provide a background on the stressors with far-reaching impacts on food security. We review the principles and advances in classical genome editing (CRISPR/Cas9) that generate DNA double-strand breaks (DSB). We discuss base editing and prime editing platforms, which are DSB- and template-free, enabling targeted base substitutions. We evaluate the application of such tools for trait improvement to develop stress-resilient crops and high-throughput mutant libraries. We examine recent developments in the regulatory landscape for genome-edited crops in various countries. Finally, we highlight the challenges and future perspectives towards crop improvement.