A method for producing a plant includes growing a plant from plant cells in which a promoter and a coding sequence under the control of the promoter have been artificially introduced and selecting the plant in which an amount of phloem tissue is increased 2.0 times or more in comparison with a wild type plant of the same species. The promoter is a promoter for a gene encoding a protein having at least 60% identity with the amino acid sequence of tracheary element differentiation inhibitory factor (TDIF) receptor (TDR) of Arabidopsis thaliana. The coding sequence encodes either (i) a protein having three common sequences composed of the amino acid sequences of SEQ ID NOS: 1 to 3 in this order starting from the N-terminal side, or (ii) a protein having 95% or more identity with the amino acid sequence of SEQ ID NO:5.
