Sucrose phosphate synthase (SPS) gene of sugarcane DIII family and plant expression vector thereof

The invention relates to a sucrose phosphate synthase (SPS) gene of sugarcane DIII family and a plant expression vector thereof. The gene S of SPS DIII is one of the following sequences: 1, DNA (deoxyribonucleic acid) sequence of 1 in a sequence table; and 2, protein sequence of 2 in a code sequence table. The gene-coded protein is a derived protein which has an amino acid residue sequence of 2 in the sequence table, or is obtained by substitution, deletion or addition of one or several amino acid residues in the amino acid residue sequence of 2 and has the same activity as 2. The plant expression vector provided by the invention contains nucleotide fragments from the 60th locus to the 2,954th locus of 1 in the sequence table, is inserted behind the constitutive starter CaMV35S of the vector pBI121 to form a new plant expression vector which is named as pBI-S of SPS DIII. The vector provided by the invention has a good application prospect in improving the sucrose content and yield of the crops or enhancing t