Crop improvement by genome editing involves the targeted alteration of genes to improve plant traits, such as stress tolerance, disease resistance or nutritional content. Techniques for the targeted modification of genomes have evolved from generating random mutations to precise base substitutions, followed by insertions, substitutions and deletions of small DNA fragments, and are finally starting to achieve precision manipulation of large DNA segments. Recent developments in base editing, prime editing and other CRISPR-associated systems have laid a solid technological foundation to enable plant basic research and precise molecular breeding. In this Review, we systematically outline the technological principles underlying precise and targeted genome-modification methods. We also review methods for the delivery of genome-editing reagents in plants and outline emerging crop-breeding strategies based on targeted genome modification. Finally, we consider potential future developments in precise genome-editing technologies, delivery methods and crop-breeding approaches, as well as regulatory policies for genome-editing products.

通过基因组编辑来改良作物涉及有针对性地改变基因以改善植物性状，例如抗逆性、抗病性或营养成分。基因组定点修饰技术已经从产生随机突变发展到精确的碱基替换，然后是小DNA片段的插入、替换和删除，最后开始实现对大DNA片段的精确操作。近年来碱基编辑、引物编辑等CRISPR相关系统的发展，为植物基础研究和精准分子育种奠定了坚实的技术基础。在这篇综述中，我们系统地概述了精确和有针对性的基因组修饰方法背后的技术原理。我们还回顾了在植物中传递基因组编辑试剂的方法，并概述了基于靶向基因组修饰的新兴作物育种策略。最后，我们考虑了精确基因组编辑技术、交付方法和作物育种方法以及基因组编辑产品的监管政策的未来潜在发展。