摘要：Precision genome editing is highly desired for crop *** recently emerged CRISPR/Cas technology offers great potential applications in precision plant genome engineering.A prime editing(PE)approach combining a reverse transcriptase(RT)with a Cas9 nickase and a“priming”extended guide RNA(gRNA)has shown a high frequency for precise genome modification in mammalian cells and several plant ***,the applications of the PE approach in dicot plants are still limited and *** designed and tested prime editors for precision editing of a synthetic sequence in a transient assay and for desirable alleles of 10 loci in tomato by stable *** data obtained by targeted deep sequencing also revealed only low PE efficiencies in both the tobacco and tomato *** assessment of the activities of the PE components uncovered that the fusion of RT to Cas9 and the structure of PE gRNAs(pegRNAs)negatively affected the cleaving activity of the Cas9 *** self-complementarity between the primer binding sequences(PBSs)and spacer sequence might pose risks to the activity of the Cas9 ***,modifying the pegRNA sequences by shortening or introducing mismatches to the PBSs to reduce their melting temperatures did not enhance the PE efficiency at the MADS-box protein(SlMBP21),alcobaca(SlALC),and acetolactate synthase 1(SlALS1)*** data show challenges of the PE approach in tomato,indicating that a further improvement of the PE system for successful applications is demanded,such as the use of improved expression systems for enriching active PE complexes.