Advances and Future Perspectives of Targeted Mutagenesis in Barley

Targeted mutagenesis technologies, commonly referred to as “genome editing”, have rapidly become transformative tools in crop breeding. Modern crop production faces mounting challenges such as climate change, emerging diseases, and shifting quality demands, creating an urgent need for breeding approaches that enable more precise genetic improvement within shorter timeframes. Targeted mutagenesis capable of introducing mutations accurately and efficiently began with the development of meganucleases and subsequently evolved through ZFNs, TALENs, and CRISPR/Cas systems. Recent technological advances, including multiplex editing and DNA-free genome editing, have made direct modification of elite cultivars increasingly feasible, helping to overcome long-standing barriers associated with genotype dependency and the complexity of polyploid genomes. Targeted mutagenesis has now been applied to a wide range of breeding targets, including disease resistance, tolerance to abiotic stresses, yield-related traits, and quality traits. Moreover, machine learning and AI are beginning to support target selection and phenotype prediction, ushering in an era in which genome editing can be integrated into breeding programs more rationally and efficiently. These scientific developments coincide with regulatory shifts in many countries toward easing restrictions on new genomic techniques (NGTs), particularly by treating SDN-1 genome-edited crops equivalently to those produced through conventional breeding. Such changes are expected to accelerate field trials, commercialization, and international collaboration. Nevertheless, several challenges remain, including bottlenecks in transformation efficiency, off-target assessment, the control of complex traits, societal acceptance, and unresolved regulatory details. Even so, genome editing is poised to become a central technology in next-generation cereal breeding, enabling the development of cultivars with greater resilience, productivity, and adaptability to diverse industrial needs.