The invention discloses a method for efficiently creating a high-
sweetness tomato
mutant based on
CRISPR / Cas9, and belongs to the technical field of
gene engineering. The method comprises the following steps: optimizing a
promoter of a
CRISPR / Cas9 (clustered regularly interspaced short palindromic repeats /
CRISPR associated
protein 9) editing carrier, and performing
gene editing on Solyc12g099190.1
gene of tomato to obtain the high-
sweetness tomato
mutant. The target sequence of the gene editing is as shown in SEQ ID NO. 2; the optimization comprises the following steps: replacing an
arabidopsis thaliana AtU6
promoter in the CRISPR / Cas9 editing vector with a tomato endogenous SlU6
promoter, and replacing a
cauliflower mosaic virus CaMV35S promoter in the CRISPR / Cas9 editing vector with a tomato endogenous SlEF promoter at the same time. The method is high in editing efficiency, and the
sweetness of the created tomato editing material is greatly improved under the condition that the
phenotype of the tomato editing material is not changed.