*3.4. Improving the CRISPR/Cas9 Genome Editing System*

The CRISPR/Cas9 system has been proven to be a highly efficient genome editing method in plants. In recent years, this genome editing system has been successfully applied in many crops, including rice, maize, soybean and tomato, for gene function studies and crop improvement, such as high yield, disease resistance, herbicide resistance, ideal plant architecture and other desirable traits. However, the CRISPR/Cas9 system has not been established in broccoli; thus, future studies should pay more attention to improving and employing the CRISPR/Cas9 system for broccoli improvement.

**Supplementary Materials:** The following are available online at https://www.mdpi.com/article/10 .3390/horticulturae7090280/s1, Table S1: Genetic mapping of genes/QTLs in broccoli.

**Author Contributions:** Conceptualization, F.H.; writing—original draft preparation, F.H.; writing review and editing, Y.L., Z.F., L.Y., M.Z., Y.Z., H.L., Y.W. and J.J.; supervision, F.H.; project administration, Z.L.; funding acquisition, Z.F. and Z.L. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was funded by grants from the Central Public-interest Scientific Institution Basal Research Fund (Grant No. IVF-BRF2020003, IVF-BRF2021003), the China Agriculture Research System (Grant No. CARS-23-08A), the Agricultural Science and Technology Innovation Program (Grant No. ASTIP), and the State Key Laboratory of Vegetable Germplasm Innovation (Grant No. SKL-VGI).

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Conflicts of Interest:** The authors declare no conflict of interest.

## **References**

