CRISPR-Cas9 technology is based on the specificity of the CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) and Cas9 (CRISPR-associated proteins) systems, which allow for the precise editing of the DNA sequence of target genes. This technology is capable of targeting specific genes for editing, thereby enabling the regulation of important crop traits such as yield, disease resistance, and stress tolerance. The purpose of this paper is to summarize the progress of CRISPR-Cas9 gene editing technology in crop improvement. Firstly, the basic principle and operation process of gene editing technology are introduced. The application of this technology in crop genetic improvement and functional gene research is summarized. In addition, the challenges and prospects of this technology in crops are discussed. Although CRISPR-Cas9 technology has great potential for crop improvement, there are still some technical difficulties and ethical issues that need to be further explored and improved.
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