New improvements in grapevine genome editing: high efficiency biallelic homozygous knock-out from regenerated plantlets by using an optimized zCas9i.

Background: For ten years, CRISPR/cas9 system has become a very useful tool for obtaining site-specific mutations on targeted genes in many plant organisms. This technology opens up a wide range of possibilities for improved plant breeding in the future. In plants, the CRISPR/Cas9 system is mostly used through stable transformation with constructs that allow for the expression of the Cas9 gene and sgRNA.