Application of CRISPR Technology in Plant Improvement: An Update Review

Clustered regularly interspaced short palindromic repeats/CRISPR‐associated protein 9 (CRISPR/Cas9) stands as a major technique in genetic engineering, offering innumerable applications for enhancing agricultural and horticultural crops. It contributes significantly to improving quality traits, managing biotic and abiotic stresses, and extending shelf life. Several genes, such as Cry genes or protease inhibitors and trypsin inhibitors, have been utilized to confer resistance against insect pests and diseases. This technique finds extensive application in medicine, agricultural, and horticultural crops. CRISPR/Cas9 has been successfully implemented in tomato, petunia, grapes, apple, and citrus, yielding promising results. For instance, in tomato, CRISPR/Cas9 has been employed with the Agrobacterium gene transfer method to provide resistance against powdery mildew disease. This review presents a comprehensive overview of CRISPR/Cas9 applications and achievements in agricultural and horticultural crops. Overall, this review highlights the potential applications of CRISPR technology in plant improvement, with limitations and challenges including off‐target mutations, size of the CRISPR/Cas9 system, delivery, and bio‐safety regulations to improve a variety of crop traits, including yield, quality, stress tolerance, disease, and herbicide resistance. It can also be used to speed up crop improvement compared to conventional breeding.