The present invention relates to a plant having an improved sugar content in fruit compared with its wild type plant, which has a mutant cyclin F-box gene comprising a nucleotide mutation that causes a non-conservative amino acid substitution in the cyclin F-box protein. The present invention also relates to a parthenocarpic plant having a mutant cyclin F-box gene comprising a nucleotide mutation that causes a non-conservative amino acid substitution in the cyclin F-box protein.
