Genome editing (GE) tools like the CRISPR/Cas9 system possess the potential to accelerate crop improvement by providing the means to modify genomes rapidly in a precise and predictable manner. The crop sugar beet, however is recalcitrant to transformation and GE mediated gene-insertion or correction has not been demonstrated, yet. This project aims to establish GE by means of Geminivirus, namely Beet curly top virus (BCTV), based replicons (GVRs) acting as plant virus vectors for the efficient delivery of SSN, sgRNA and repair templates for homologous recombination-directed repair (HDR) and aims to deliver the proof of concept for gene insertion and modification by CRISPR based GE. Parameters that shall be improved are precision and efficacy of HDR based GE to allow sugar beet to take full advantages from the new technology.