Fuente: WIPO "processing tomato" The invention relates to an application of a tomato SlCOST1 gene in creating a new tomato germplasm. According to the invention, the SlCOST1 gene (with a nucleotide sequence shown as SEQ ID NO.1) of the tomato is knocked out by virtue of a CRISPR/Cas9 technical means, so that the plant height of a plant is remarkably reduced, fruits are miniaturized, seeds are reduced, the fructose content is increased, and a new tomato dwarfing germplasm is obtained. Compared with the prior art, the new tomato germplasm which is short and small in plant type, small in fruit and higher in fructose concentration and sweetness has the advantages of being capable of effectively improving the planting density of tomatoes, fully utilizing the cultivation space, improving the lodging resistance and the like, has the characteristics of few seeds and high sugar of the fruits, is more beneficial to industrial processing, has important economic value, and is worthy of popularization and application. And a target screening gene is provided for molecular assisted breeding.