The role of CRISPR in modern plant breeding: overcoming breeding barriers and legislative challenges through transgene-free genome editing.

Abstract

Traditional plant breeding techniques-such as crossbreeding, mutation breeding, and marker-assisted selection-have significantly contributed to crop improvement over the past century. However, these methods are often limited by long breeding cycles, low precision, and the unintended transfer of undesirable traits. To address these challenges, transgenic breeding emerged as a powerful tool, enabling the introduction of specific foreign genes to confer desirable traits such as pest resistance or herbicide tolerance. While highly effective and precise, transgenic approaches face considerable regulatory and public acceptance barriers, particularly in regions with strict GMO legislation. The advent of CRISPR/Cas genome editing has revolutionized plant breeding by enabling precise, efficient, and targeted modification of native genes, significantly accelerating the development of improved crops. Among CRISPR-based methods, transgene-free genome editing has gained prominence for producing enhanced plant varieties without integrating foreign DNA, thus avoiding many regulatory constraints associated with GMOs. This review aims to provide a comprehensive overview of CRISPR-mediated genome editing technologies in crop innovation, emphasizing especially the use of transgene-free approaches in modern plant breeding and their transformative potential to overcome the limitations of conventional methods while providing a regulation-friendly pathway for crop improvement.